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Sample records for wc sedentary behavior

  1. Leisure-Time Physical Activity Does not Attenuate the Association Between Occupational Sedentary Behavior and Obesity: Results From Alberta's Tomorrow Project.

    Science.gov (United States)

    Nicholas, Joshua A; Lo Siou, Geraldine; Lynch, Brigid M; Robson, Paula J; Friedenreich, Christine M; Csizmadi, Ilona

    2015-12-01

    Sedentary behavior has been proposed as a risk factor for obesity that is distinct from physical inactivity. This study aimed to examine the association between occupational sedentary behavior and obesity, and to determine if this association is independent of leisure-time physical activity (LTPA). Fully employed participants enrolled between 2001 and 2008 to Alberta's Tomorrow Project, a prospective cohort study in Alberta, Canada, were studied (n = 12,409). Associations between occupational sedentary behavior and waist circumference (WC), waist-to-hip ratio (WHR), and body mass index (BMI) were examined using multiple binary and multinomial logistic regressions. In men, a positive association was observed between daily occupational sedentary hours and WC, WHR, BMI, and with high risk profiles that incorporated both BMI and WC (P < .01). Controlling for vigorous-intensity LTPA in all models strengthened associations between sedentary behavior and measures of obesity. In contrast, inverse associations were observed for occupational sedentary hours and WHR for women (P < .05). In fully employed men, occupational sedentary behavior was positively associated with obesity risk that was not attenuated by physical activity. In women, an increase in obesity risk was not observed with sedentary behavior. Gender differences in the health effects of sedentary behavior require further study.

  2. Cold compaction behavior and pressureless sinterability of ball milled WC and WC/Cu powders

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    Hashemi Seyed R.

    2016-01-01

    Full Text Available In this research, cold compaction behavior and pressureless sinterability of WC, WC-10%wtCu and WC-30%wtCu powders were investigated. WC and WC/Cu powders were milled in a planetary ball mill for 20h. The milled powders were cold compacted at 100, 200, 300 and 400 MPa pressures. The compressibility behavior of the powders was evaluated using the Heckel, Panelli-Ambrosio and Ge models. The results showed that the Panelli-Ambrosio was the preferred equation for description the cold compaction behavior of the milled WC and WC-30%wtCu powders. Also, the most accurate model for describing the compressibility of WC-10%wtCu powders was the Heckel equation. The cold compacts were sintered at 1400°C. It was found that by increasing the cold compaction pressure of powder compacts before sintering, the sinterability of WC-30%wtCu powder compacts was enhanced. However, the cold compaction magnitude was not affected significantly on the sinterability of WC and WC-10%wtCu powders. The microstructural investigations of the sintered samples by Scanning Electron Microscopy (SEM confirmed the presence of porosities at the interface of copper-tungsten carbide phases.

  3. The motivation to be sedentary predicts weight change when sedentary behaviors are reduced.

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    Epstein, Leonard H; Roemmich, James N; Cavanaugh, Meghan D; Paluch, Rocco A

    2011-02-22

    Obesity is correlated with a sedentary lifestyle, and the motivation to be active or sedentary is correlated with obesity. The present study tests the hypothesis that the motivation to be active or sedentary is correlated with weight change when children reduce their sedentary behavior. The motivation to be active or sedentary, changes in weight, and accelerometer assessed physical activity were collected for 55 families with overweight/obese children who participated in a nine-week field study to examine behavior and weight change as a function of reducing sedentary behavior. Children were studied in three 3-week phases, baseline, reduce targeted sedentary behaviors by 25% and reduce targeted sedentary behaviors by 50%. The targeted sedentary behaviors included television, video game playing, video watching, and computer use. The reinforcing value of sedentary behavior but not physical activity, was correlated with weight change, as losing weight was associated with lower reinforcing value of sedentary behaviors. Reducing sedentary behavior was not associated with a significant change in objectively measured physical activity, suggesting the main way in which reducing sedentary behavior influenced weight change is by complementary changes in energy intake. Estimated energy intake supported the hypothesis that reducing sedentary behaviors influences weight by reducing energy intake. These data show that the motivation to be sedentary limits the effects of reducing sedentary behavior on weight change in obese children. © 2011 Epstein et al; licensee BioMed Central Ltd.

  4. The motivation to be sedentary predicts weight change when sedentary behaviors are reduced

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    Paluch Rocco A

    2011-02-01

    Full Text Available Abstract Background Obesity is correlated with a sedentary lifestyle, and the motivation to be active or sedentary is correlated with obesity. The present study tests the hypothesis that the motivation to be active or sedentary is correlated with weight change when children reduce their sedentary behavior. Methods The motivation to be active or sedentary, changes in weight, and accelerometer assessed physical activity were collected for 55 families with overweight/obese children who participated in a nine-week field study to examine behavior and weight change as a function of reducing sedentary behavior. Children were studied in three 3-week phases, baseline, reduce targeted sedentary behaviors by 25% and reduce targeted sedentary behaviors by 50%. The targeted sedentary behaviors included television, video game playing, video watching, and computer use. Results The reinforcing value of sedentary behavior but not physical activity, was correlated with weight change, as losing weight was associated with lower reinforcing value of sedentary behaviors. Reducing sedentary behavior was not associated with a significant change in objectively measured physical activity, suggesting the main way in which reducing sedentary behavior influenced weight change is by complementary changes in energy intake. Estimated energy intake supported the hypothesis that reducing sedentary behaviors influences weight by reducing energy intake. Conclusions These data show that the motivation to be sedentary limits the effects of reducing sedentary behavior on weight change in obese children. Trial registration ClinicalTrials.gov: NCT00962247

  5. Infiltration Behavior Of Mechanical Alloyed 75 wt% Cu-25 wt% WC Powders Into Porous WC Compacts

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    Şelte A.

    2015-06-01

    Full Text Available In this work infiltration behavior of mechanical alloyed 75 wt% Cu – 25 wt% WC powders into porous WC compacts were studied. Owing to their ductile nature, initial Cu powders were directly added to mechanical alloying batch. On the other hand initial WC powders were high energy milled prior to mechanical alloying. Contact infiltration method was selected for densification and compacts prepared from processed powders were infiltrated into porous WC bodies. After infiltration, samples were characterized via X-Ray diffraction studies and microstructural evaluation of the samples was carried out via scanning electron microscopy observations. Based on the lack of solubility between WC and Cu it was possible to keep fine WC particles in Cu melt since solution reprecipitation controlled densification is hindered. Also microstructural characterizations via scanning electron microscopy confirmed that the transport of fine WC fraction from infiltrant to porous WC skeleton can be carried out via Cu melt flow during infiltration.

  6. Novel strategies for sedentary behavior research.

    Science.gov (United States)

    Rosenberg, Dori E; Lee, I-Min; Young, Deborah Rohm; Prohaska, Thomas R; Owen, Neville; Buchner, David M

    2015-06-01

    This article reports on the "Novel Strategies for Sedentary Behavior Research" session of the Sedentary Behavior: Identifying Research Priorities workshop. The purpose of this session of the workshop were to propose strategies for accomplishing a research agenda in dealing with sedentary behavior and to consider research priorities for people at high risk for excess sedentary behavior. The four major recommendations from this workshop were as follows: 1) To add repeated objective measures of physical activity and sedentary behavior to existing cohort studies and standardize approaches to measurement and analysis. Epidemiologic studies will be the most efficient design for addressing some research questions. 2) To increase research efficiency, consider the advantages of a network of connected research studies and health systems. Advantages include access to existing data in electronic health records. 3) To carefully select a variety of high-risk study populations and preplan collaboration among studies in intervention research. This strategy can efficiently address the breadth of issues in sedentary behavior research. 4) To include comparative effectiveness designs and pure environmental interventions in intervention research. This strategy facilitates and enhances translation of interventions into practice.

  7. Sedentary behavior and residual-specific mortality

    OpenAIRE

    Paul D. Loprinzi; Meghan K. Edwards; Eveleen Sng; Ovuokerie Addoh

    2016-01-01

    Background: The purpose of this study was to examine the association of accelerometer-assessed sedentary behavior and residual-specific mortality. Methods: Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used (N = 5536), with follow-up through 2011. Sedentary behavior was objectively measured over 7 days via accelerometry. Results: When expressing sedentary behavior as a 60 min/day increase, the hazard ratio across the models ranged from 1.07-1.40 (P < 0...

  8. Sedentary behavior patterns in non-pregnant and pregnant women

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    Marquis Hawkins

    2017-06-01

    Full Text Available Sedentary behavior has been associated with adverse health outcomes among pregnant women; however, few studies have characterized sedentary behavior patterns in this population. We described patterns of accelerometer-determined indicators of sedentary behavior among a national sample of US pregnant (n = 234 women and non-pregnant (n = 1146 women participating in the NHANES 2003-06 cycles. We included women with ≥4 days of accelerometer wear of ≥10 h/day. A count threshold of <100 cpm was used to describe sedentary behavior as: 1 total accumulated sedentary time by bout length categories; 2 accumulated sedentary time within discrete bout length categories; 3 mean, median, and usual bout length; and 4 and bout frequency. Both non-pregnant and pregnant women spent up to 60% of their accelerometer wear time in sedentary behavior depending on the minimum bout threshold applied. Sedentary time was higher among pregnant women compared to non-pregnant women when lower bout thresholds (i.e. 10 min or less were applied. The majority of total sedentary time was accumulated in bouts lasting <10 min. The women averaged less than two prolonged sedentary bouts (i.e., ≥30 min per day, which accounted for nearly 20% of total accumulated sedentary time. When applying a minimum threshold of at least 15 min, sedentary time increased across pregnancy trimesters, while sedentary time was similar across trimesters when using lower thresholds. These findings provide the first characterization of accelerometer-determined indicators of sedentary behavior in pregnant women. The minimum bout threshold applied influenced estimates of sedentary time and patterns sedentary time accumulation across pregnancy trimesters.

  9. Associations between change in sedentary behavior and outcome in standard behavioral weight loss treatment.

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    Kerrigan, Stephanie G; Call, Christine; Schaumberg, Katherine; Forman, Evan; Butryn, Meghan L

    2018-03-01

    Sedentary behavior, particularly in prolonged periods, is an important determinant of health. Little research exploring changes in sedentary behavior during behavioral weight loss programs exists. This study evaluated the magnitude of changes in total and prolonged sedentary behavior and how these changes related to changes in weight and cardiovascular outcomes during a behavioral weight loss program. Participants (n = 450) in two lifestyle modification programs underwent assessments of sedentary behavior (by accelerometry), weight, waist circumference, blood pressure, and resting heart rate at baseline and after 6 months of treatment. Sedentary behavior was defined as both total and prolonged (≥30 continuous minutes) sedentary minutes/day. Reductions in total and prolonged sedentary time were significant and were accounted for by increases in moderate-to-vigorous physical activity (MVPA). Only changes in MVPA significantly predicted change in weight when entered into a model simultaneously with changes in sedentary behavior. Changes in total and prolonged sedentary time were not associated with changes in waist circumference, heart rate, or blood pressure. Change in sedentary time was not independently associated with change in health outcomes during a behavioral weight loss treatment. High variability in changes in sedentary time indicate that individual differences may be important to examine. Reducing sedentary time may not be powerful enough to impact these health outcomes above the effects of other changes made during these programs; alternatively, it may be that increasing focus in treatment on reducing sedentary time may engender greater decreases in sedentariness, which could lead to better health outcomes.

  10. A Review of Different Behavior Modification Strategies Designed to Reduce Sedentary Screen Behaviors in Children

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    Jeremy A. Steeves

    2012-01-01

    Full Text Available Previous research suggests that reducing sedentary screen behaviors may be a strategy for preventing and treating obesity in children. This systematic review describes strategies used in interventions designed to either solely target sedentary screen behaviors or multiple health behaviors, including sedentary screen behaviors. Eighteen studies were included in this paper; eight targeting sedentary screen behaviors only, and ten targeting multiple health behaviors. All studies used behavior modification strategies for reducing sedentary screen behaviors in children (aged 1–12 years. Nine studies only used behavior modification strategies, and nine studies supplemented behavior modification strategies with an electronic device to enhance sedentary screen behaviors reductions. Many interventions (50% significantly reduced sedentary screen behaviors; however the magnitude of the significant reductions varied greatly (−0.44 to −3.1 h/day and may have been influenced by the primary focus of the intervention, number of behavior modification strategies used, and other tools used to limit sedentary screen behaviors.

  11. A review of different behavior modification strategies designed to reduce sedentary screen behaviors in children.

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    Steeves, Jeremy A; Thompson, Dixie L; Bassett, David R; Fitzhugh, Eugene C; Raynor, Hollie A

    2012-01-01

    Previous research suggests that reducing sedentary screen behaviors may be a strategy for preventing and treating obesity in children. This systematic review describes strategies used in interventions designed to either solely target sedentary screen behaviors or multiple health behaviors, including sedentary screen behaviors. Eighteen studies were included in this paper; eight targeting sedentary screen behaviors only, and ten targeting multiple health behaviors. All studies used behavior modification strategies for reducing sedentary screen behaviors in children (aged 1-12 years). Nine studies only used behavior modification strategies, and nine studies supplemented behavior modification strategies with an electronic device to enhance sedentary screen behaviors reductions. Many interventions (50%) significantly reduced sedentary screen behaviors; however the magnitude of the significant reductions varied greatly (-0.44 to -3.1 h/day) and may have been influenced by the primary focus of the intervention, number of behavior modification strategies used, and other tools used to limit sedentary screen behaviors.

  12. Executive function influences sedentary behavior: A longitudinal study

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    Paul D. Loprinzi

    2016-10-01

    Full Text Available Background: No study has evaluated the effects of executive function on follow-up sedentary behavior, which was this study’s purpose. Methods: A longitudinal design was employed among 18 young adult college students (Mage = 23.7 years; 88.9% female. Accelerometer-determined sedentary behavior and physical activity, along with executive function, were assessed at baseline. Approximately 8 weeks later, re-assessment of accelerometer-determined sedentary behavior and physical activity occurred. Executive function was assessed using the Parametric Go/No-Go (PGNG computer task. From this, 2 primary executive function outcome parameters were evaluated, including the Simple Rule and Repeating Rule. Results: After adjusting for baseline sedentary behavior, age, gender, body mass index and baseline moderate-to-vigorous physical activity (MVPA, for every 25% increase in the number of correctly identified targets for the Repeating rule at the baseline assessment, participants engaged in 91.8 fewer minutes of sedentary behavior at the follow-up assessment (β = -91.8; 95% CI: -173.5, -10.0; P = 0.03. Results were unchanged when also adjusting for total baseline or follow-up physical activity. Conclusion: Greater executive function is associated with less follow-up sedentary behavior.

  13. The motivation to be sedentary predicts weight change when sedentary behaviors are reduced

    OpenAIRE

    Epstein, Leonard H; Roemmich, James N; Cavanaugh, Meghan D; Paluch, Rocco A

    2011-01-01

    Abstract Background Obesity is correlated with a sedentary lifestyle, and the motivation to be active or sedentary is correlated with obesity. The present study tests the hypothesis that the motivation to be active or sedentary is correlated with weight change when children reduce their sedentary behavior. Methods The motivation to be active or sedentary, changes in weight, and accelerometer assessed physical activity were collected for 55 families with overweight/obese children who participa...

  14. [Occupational sedentary behaviors and physical activity at work].

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    Dutheil, Frédéric; Ferrières, Jean; Esquirol, Yolande

    Sedentary behaviors are a leading cause of preventable mortality in developed countries. We mainly have sedentary behaviors at work. Sedentary behaviors must be considered as an occupational risk, and therefore must be a major concern for managers and physicians/health researchers. Recreational physical activity only partly compensates for the negative effects of physical inactivity at work. Physical activity at work without excess (walking, standing) is beneficial. Initiatives to reduce physical inactivity and increase physical activity among employees are effective in terms of mental health, physical health, and productivity. Prevention of sedentary behaviors at work is a win-win partnership between employers and employees. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. Effects of WC phase contents on the microstructure, mechanical properties and tribological behaviors of WC/a-C superlattice coatings

    Energy Technology Data Exchange (ETDEWEB)

    Pu, Jibin [Key Laboratory of Marine Materials and Related Technologies, Key Laboratory of Marine Materials and Protective Technologies of Zhejiang Province, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); He, Dongqing [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Wang, Liping, E-mail: lpwang@licp.cas.cn [Key Laboratory of Marine Materials and Related Technologies, Key Laboratory of Marine Materials and Protective Technologies of Zhejiang Province, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2015-12-01

    Graphical abstract: - Highlights: • WC/a-C superlattice coatings were synthesized with various WC phase content. • Superlattice structure diminished residual stress and densified microstructure. • Nanocomposite coating with W 5.43 at.% achieved the optimal tribological properties. • Friction triggered WO{sub 3} lead to a low friction coefficient at 200 °C. - Abstract: Nanocomposite WC/a-C coatings with variable contents of tungsten carbide (WC{sub 1−x}) and amorphous carbon (a-C) were successfully fabricated using a magnetron sputtering process. The microstructure, mechanical properties and tribological behaviors of the as-fabricated coatings were investigated and compared. The results showed that the “superlattice coating” feature of an alternating multilayer structure with a-C and WC{sub 1−x} nanocrystallites layers on the nanoscale was formed. These multilayer superlattice structures led to diminished residual stress and improved the strength of the adhesion to the substrate. The WC/a-C coating with W 5.43 at.% exhibited low friction coefficients of 0.05 at 25 °C and 0.28 at 200 °C. This significant improvement in the tribological performances of the WC/a-C coating was mainly attributed to the superior “superlattice” microstructure and the formation of a continuously compacted tribofilms, which was rich in graphitized carbon at 25 °C and dominated by the friction triggered WO{sub 3} at 200 °C. Moreover, the WC/a-C coating with W 5.43 at.% achieved optimal anti-wear properties at 25 °C due to the synergistic combination of the enhancement effects of the WC{sub 1−x} nanoparticles and the partition effect from the transfer film that restricted direct contact of the steel ball with the coating and thus prevented further intense wear. The accelerated wear of the WC/a-C coating with the increase of the WC phase content at 200 °C might be due to the combination of oxidation wear and abrasive wear that originated from the WC{sub 1−x} phase.

  16. Diurnal Patterns and Correlates of Older Adults' Sedentary Behavior.

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    Jelle Van Cauwenberg

    Full Text Available Insights into the diurnal patterns of sedentary behavior and the identification of subgroups that are at increased risk for engaging in high levels of sedentary behavior are needed to inform potential interventions for reducing older adults' sedentary time. Therefore, we examined the diurnal patterns and sociodemographic correlates of older adults' sedentary behavior(s.Stratified cluster sampling was used to recruit 508 non-institutionalized Belgian older adults (≥ 65 years. Morning, afternoon, evening and total sedentary time was assessed objectively using accelerometers. Specific sedentary behaviors, total sitting time and sociodemographic attributes were assessed using an interviewer-administered questionnaire.Participants self-reported a median of 475 (Q1-Q3 = 383-599 minutes/day of total sitting time and they accumulated a mean of 580 ± 98 minutes/day of accelerometer-derived sedentary time. Sedentary time was lowest during the morning and highest during the evening. Older participants were as sedentary as younger participants during the evening, but they were more sedentary during daytime. Compared to married participants, widowers were more sedentary during daytime. Younger participants (< 75 years, men and the higher educated were more likely to engage in (high levels of sitting while driving a car and using the computer. Those with tertiary education viewed 29% and 22% minutes/day less television compared to those with primary or secondary education, respectively. Older participants accumulated 35 sedentary minutes/day more than did younger participants and men accumulated 32 sedentary minutes/day more than did women.These findings highlight diurnal variations and potential opportunities to tailor approaches to reducing sedentary time for subgroups of the older adult population.

  17. Issues and Challenges in Sedentary Behavior Measurement

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    Kang, Minsoo; Rowe, David A.

    2015-01-01

    Previous research has shown the negative impact of sedentary behavior on health, including cardiovascular risk factors, chronic disease-related morbidity, and mortality. Accurate measurement of sedentary behavior is thus important to plan effective interventions and to inform public health messages. This article (a) provides an overview of the…

  18. Energy expenditure of interruptions to sedentary behavior

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    Strath Scott J

    2011-06-01

    Full Text Available Abstract Background Advances in technology, social influences and environmental attributes have resulted in substan-tial portions of the day spent in sedentary pursuits. Sedentary behavior may be a cause of many chronic diseases including obesity, insulin resistance, type 2 diabetes and the metabolic syndrome. Research demonstrated that breaking up sedentary time was beneficially associated with markers of body composition, cardiovascular health and type 2 diabetes. Therefore, the purpose of this study was to quantify the total energy expenditure of three different durations of physical activity within a 30-minute sedentary period and to examine the potential benefits of interrupting sedentary behavior with physical activity for weight control. Methods Participants completed four consecutive 30-minute bouts of sedentary behavior (reading, working on the computer, or doing other desk activities with and without interruptions of walking at a self-selected pace. Bout one contained no walking interruptions. Bout two contained a 1-minute walking period. Bout three contained a 2-minute walking period. Bout four contained a 5-minute walking period. Body composition and resting metabolic rate were assessed. Result Twenty males and females (18-39 years completed this study. Results of the repeated measures analysis of variance with post-hoc testing showed that significantly more energy was expended during each 30 minute sedentary bout with a walking break than in the 30 minute sedentary bout (p Conclusions This study demonstrated that making small changes, such as taking a five minute walking break every hour could yield beneficial weight control or weight loss results. Therefore, taking breaks from sedentary time is a potential outlet to prevent obesity and the rise of obesity in developed countries.

  19. Physiology of Sedentary Behavior and Its Relationship to Health Outcomes

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    Thyfault, John P; Du, Mengmeng; Kraus, William E; Levine, James A; Booth, Frank W

    2014-01-01

    Purpose This paper reports on the findings and recommendations of the “Physiology of Sedentary Behavior and its Relationship to Health Outcomes” group, a part of a larger workshop entitled Sedentary Behavior: Identifying Research Priorities sponsored by the National Heart, and Lung and Blood Institute and the National Institute on Aging, which aimed to establish sedentary behavior research priorities. Methods The discussion within our workshop lead to the formation of critical physiological research objectives related to sedentary behaviors, that if appropriately researched would greatly impact our overall understanding of human health and longevity. Results and Conclusions Primary questions are related to physiological “health outcomes” including the influence of physical activity vs. sedentary behavior on function of a number of critical physiological systems (aerobic capacity, skeletal muscle metabolism and function, telomeres/genetic stability, and cognitive function). The group also derived important recommendations related to the “central and peripheral mechanisms” that govern sedentary behavior and how energy balance has a role in mediating these processes. General recommendations for future sedentary physiology research efforts include that studies of sedentary behavior, including that of sitting time only, should focus on the physiological impact of a “lack of human movement” in contradistinction to the effects of physical movement and that new models or strategies for studying sedentary behavior induced adaptations and links to disease development are needed to elucidate underlying mechanism(s). PMID:25222820

  20. Longitudinal Associations Between Sedentary Behavior of Adolescent Girls, Their Mothers, and Best Friends.

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    Raudsepp, Lennart; Riso, Eva-Maria

    2017-08-01

    The objective of this study was to examine the prospective relationship and changes in sedentary behavior between adolescent girls, their mothers and best friends over time. The results are based on 122 girls aged 11-12 years at baseline measurement, their mothers and best friends who completed ecological momentary assessment diary for the assessment of sedentary behavior. All measurements were taken at 3 time points separated by one year. We used structural equation modeling to examine associations among sedentary behavior of adolescent girls, their mothers and best friends. A linear growth model for adolescent girls' and their best friends' sedentary behavior fit the data well, revealing an overall significant increase in sedentary behavior across time. Initial levels of mothers' and best friends' sedentary behavior were positively related with sedentary behavior of adolescent girls. The changes of adolescent girls' and best friends' sedentary behavior across 3 years were positively related. Cross-lagged panel analysis demonstrated significant reciprocal effects between adolescent girls' and best friends' sedentary behavior. Mothers' sedentary behavior at baseline predicted daughters' sedentary behavior at 1-year follow-up and vice versa. From early to midadolescence, changes in adolescent girls' sedentary behavior were associated with changes in best friends' sedentary behavior. These findings suggest reciprocal associations between sedentary behavior of adolescent girls and their best friends.

  1. Experimentally increasing sedentary behavior results in decreased life satisfaction

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    Edwards, Meghan K.; Loprinzi, Paul D.

    2017-01-01

    Background: No study has experimentally manipulated sedentary behavior and evaluated its effect on life satisfaction. Thus, the purpose of this study was to evaluate the effects of a free-living, sedentary behavior-inducing randomized controlled intervention on life satisfaction. Methods: Active, young adults between the ages of 18-35 were recruited and randomly assigned into a sedentary behavior intervention group (n = 26) or a control group (n = 13). The intervention group par...

  2. Sedentary behavior at obese children and youth

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    Milanović Jasmina

    2012-01-01

    Full Text Available This work presents a research of sedentary behavior at obese children and youth, which was examined considering the amount of time spent on activities that include computers and television, and the amount of children's physical engagement. The sample is made of 375 obese children and adolescents, aged 12-18 years, 47.7% of which are male, and 52.1% female. They all filled in the questionnaire designed for the purpose of 'Cigotica' program. The questionnaire examined the amount of time spent on sedentary behavior. The children's perception of the amount of time spent watching television and using the computer is 4.9 hours, and it is lower than parent's perception, 5.2 hours . The frequency analysis shows that 79.9% of these children do not practice regular sports activities, and also that only 30.7% of them has hobbies, most of which include sedentary behavior. Differences between males and females were found by comparing means of the amount of time spent using television and computer, as well as the amount of physical engagement through sport activities and hobbies. These results are coherent to the results of previous research of effect of sedentary behavior on obesity.

  3. Health risks, correlates, and interventions to reduce sedentary behavior in young people.

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    Salmon, Jo; Tremblay, Mark S; Marshall, Simon J; Hume, Clare

    2011-08-01

    Opportunities for young people to be sedentary have increased during leisure time, study time, and transportation time. This review paper focuses on sedentary behaviors among young people aged 2-18 years and includes evidence of the relationship between sedentary behavior and health risk indicators, an overview of public health recommendations, the prevalence of key sedentary behaviors, evidence of correlates of sedentary behavior and the effectiveness of interventions to reduce sedentary behaviors. Although this is a narrative style review and not systematic, where possible, findings from relevant review papers were summarized and a search of more recent literature was performed using computer-based databases such as PubMed, Google Scholar, ERIC, PsycINFO, Social Science Index, SportDiscus, and Health Reference Center - Academic. Young people spend 2-4 hours per day in screen-based behaviors and 5-10 hours per day sedentary. Ethnicity, sociodemographic status, having a TV set in the bedroom, and parental behavior appear to be the most consistent correlates of TV viewing time; however, few recent studies aiming to reduce TV viewing or sedentary time among young people have been successful. A growing body of evidence supports the development of public health recommendations to limit the time spent in screen-based behaviors. More research is needed to examine the prospective and experimental evidence of associations between overall sedentary time and health, determinants of sedentary behaviors other than screen-based behaviors, and interventions to reduce overall sedentary time or even alternative sedentary behaviors, such as transport- or education-related sitting time. Copyright © 2011 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  4. Sedentary Behaviors and Adiposity in Young People: Causality and Conceptual Model.

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    Biddle, Stuart J H; Pearson, Natalie; Salmon, Jo

    2018-01-01

    Research on sedentary behavior and adiposity in youth dates back to the 1980s. Sedentary behaviors, usually screen time, can be associated with adiposity. Although the association usually is small but significant, the field is complex, and results are dependent on what sedentary behaviors are assessed and may be mediated and moderated by other behaviors.

  5. Fretting and wear behaviors of Ni/nano-WC composite coatings in dry and wet conditions

    International Nuclear Information System (INIS)

    Benea, Lidia; Başa, Sorin-Bogdan; Dănăilă, Eliza; Caron, Nadège; Raquet, Olivier; Ponthiaux, Pierre; Celis, Jean-Pierre

    2015-01-01

    Highlights: • The friction and wear properties of Ni/nano-WC composite were studied. • Nano-WC reinforcement decreased friction coefficient in dry and wet conditions. • Nano-WC reinforcement fraction was seen to be 12 wt.%. • Nanohardness increased by 27% compared to nickel without WC reinforcements. • Ennoblement of OCP corresponding to the Ni/nano-WC composite coating. - Abstract: The fretting and wear behaviors of Ni/nano-WC composite coatings were studied by considering the effect of fretting frequency of 1 Hz during 10,000 cycles, at different applied loads in dry or wet conditions. The studies were performed on a ball-on-disk tribometer and the results were compared with pure Ni coating. The nanohardness of pure Ni and Ni/nano-WC composite coatings was tested by nanoindentation technique. To evaluate the wet wear (tribocorrosion) behavior the open circuit potential (OCP) was measured before, during and after the fretting tests at room temperature in the solution that simulates the primary water circuit of Pressurized Water Reactors (PWRs). The results show that Ni/nano-WC composite coatings exhibited a low friction coefficient, high nanohardness and wear resistance compared with pure Ni coatings under similar experimental conditions. Ni/nano-WC composite coatings were obtained on stainless steel support by electrochemical codeposition of nano-sized WC particles (diameter size of ∼60 nm) with nickel, from a standard nickel Watts plating bath. The surface morphology and the composition of the coatings were characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDX) respectively

  6. Why Older Adults Spend Time Sedentary and Break Their Sedentary Behavior: A Mixed-Methods Approach Using Life-Logging Equipment.

    Science.gov (United States)

    Dontje, Manon L; Leask, Calum F; Harvey, Juliet; Skelton, Dawn A; Chastin, Sebastien F M

    2018-04-01

    Older adults are recommended to reduce their sedentary time to promote healthy ageing. To develop effective interventions identifying when, why, and how older adults are able to change their sitting habits is important. The aim of this mixed-method study was to improve our understanding of reasons for (breaking) sedentary behavior in older adults. Thirty older adults (74.0 [±5.3] years old, 73% women) were asked about their believed reasons for (breaking) sedentary behavior, and about their actual reasons when looking at a personal storyboard with objective records of activPAL monitor data and time-lapse camera pictures showing all their periods of sedentary time in a day. The most often mentioned believed reason for remaining sedentary was television/radio (mentioned by 48.3%), while eating/drinking was most often mentioned as actual reason (96.6%). Only 17.2% believed that food/tea preparation was a reason to break up sitting, while this was an actual reason for 82.8% of the study sample. Results of this study show that there is a discrepancy between believed and actual reasons for (breaking) sedentary behavior. These findings suggest developing interventions utilizing the actual reasons for breaking sedentary behavior to reduce sedentary time in older adults.

  7. Factors associated with communication-based sedentary behaviors among youth: are talking on the phone, texting, and instant messaging new sedentary behaviors to be concerned about?

    Science.gov (United States)

    Leatherdale, Scott T

    2010-09-01

    Sedentary behavior research typically only examines screen time activities and not communication time activities, such as talking on the phone, texting, or instant messaging. Data from 2,449 grade 5 to 8 students were used to examine factors associated with the time youth spent in communication-based sedentary behaviors. Screen time, physical activity, grade, and gender were associated with moderate and high communication time. Future research on sedentary behavior should include measures of communication time.

  8. Breast cancer survivors' beliefs and preferences regarding technology-supported sedentary behavior reduction interventions.

    Science.gov (United States)

    Lloyd, Gillian R; Oza, Sonal; Kozey-Keadle, Sarah; Pellegrini, Christine A; Conroy, David E; Penedo, Frank J; Spring, Bonnie J; Phillips, Siobhan M

    2016-01-01

    Less time spent in sedentary behaviors is associated with improved health and disease outcomes in breast cancer survivors. However, little is known about survivors' interest in sedentary behavior reduction interventions and how to effectively reduce this risk behavior. The purpose of this study was to explore breast cancer survivors' interest in and preferences for technology-supported sedentary behavior reduction interventions. Breast cancer survivors [n=279; M age =60.7 ( SD =9.7)] completed a battery of online questionnaires. Descriptive statistics were calculated for all data. To examine potential relationships between demographic, disease and behavioral factors, and survivors' interest in a technology-supported sedentary behavior reduction intervention, we conducted logistic regression analyses. These same factors were examined in relation to the perceptions of the effectiveness of such intervention using multiple regression analyses. On average, survivors spent 10.1 ( SD =4.3) hours/day in sedentary activity. They believed prolonged periods of sedentary behavior were harmful to their health (87.0%) and that reducing sedentary behavior could improve their health (88.4%). Survivors believed they should move around after 30-60 (56.7%) or ≥60 (29.9%) minutes of sedentary behavior and indicated they were most likely to replace sedentary behaviors with walking around (97.1%) or walking in place (73.4%). The majority of survivors (79.9%) was interested in participating in a technology-supported sedentary behavior reduction intervention and indicated they would use a smartphone application (61.3%) 2-3 times/day (48.0%), 6 to 7 days/week (52.0%). Most survivors (73.5%) believed reminders would help them decrease sedentary behavior and preferred they be delivered after sitting for 60 minutes (60.5%) via vibrations on a wrist worn activity tracker (77.3%) or text messages (54.4%). Technology-supported sedentary behavior reduction interventions may be feasible and

  9. Breast Cancer Survivors’ Beliefs and Preferences Regarding Technology-Supported Sedentary Behavior Reduction Interventions

    Directory of Open Access Journals (Sweden)

    Bonnie J. Spring

    2016-08-01

    Full Text Available Purpose: Less time spent in sedentary behaviors is associated with improved health and disease outcomes in breast cancer survivors. However, little is known about survivors’ interest in sedentary behavior reduction interventions and how to effectively reduce this risk behavior. The purpose of this study was to explore breast cancer survivors’ interest in and preferences for technology-supported sedentary behavior reduction interventions. Methods: Breast cancer survivors (n = 279; Mage = 60.7 (SD = 9.7 completed a battery of online questionnaires. Descriptive statistics were calculated for all data. To examine potential relationships between demographic, disease and behavioral factors, and survivors’ interest in a technology-supported sedentary behavior reduction intervention, we conducted logistic regression analyses. These same factors were examined in relation to the perceptions of the effectiveness of such intervention using multiple regression analyses. Results: On average, survivors spent 10.1 (SD = 4.3 hours/day in sedentary activity. They believed prolonged periods of sedentary behavior were harmful to their health (87.0% and that reducing sedentary behavior could improve their health (88.4%. Survivors believed they should move around after 30–60 (56.7% or ≥ 60 (29.9% minutes of sedentary behavior and indicated they were most likely to replace sedentary behaviors with walking around (97.1% or walking in place (73.4%. The majority of survivors (79.9% was interested in participating in a technology-supported sedentary behavior reduction intervention and indicated they would use a smartphone application (61.3% 2–3 times/day (48.0%, 6 to 7 days/week (52.0%. Most survivors (73.5% believed reminders would help them decrease sedentary behavior and preferred they be delivered after sitting for 60 minutes (60.5% via vibrations on a wrist worn activity tracker (77.3% or text messages (54.4%. Conclusions: Technology-supported sedentary

  10. Associations of sedentary behavior, sedentary bouts and breaks in sedentary time with cardiometabolic risk in children with a family history of obesity.

    Science.gov (United States)

    Saunders, Travis John; Tremblay, Mark Stephen; Mathieu, Marie-Ève; Henderson, Mélanie; O'Loughlin, Jennifer; Tremblay, Angelo; Chaput, Jean-Philippe

    2013-01-01

    Although reports in adults suggest that breaks in sedentary time are associated with reduced cardiometabolic risk, these findings have yet to be replicated in children. To investigate whether objectively measured sedentary behavior, sedentary bouts or breaks in sedentary time are independently associated with cardiometabolic risk in a cohort of Canadian children aged 8-11 years with a family history of obesity. Data from 286 boys and 236 girls living in Quebec, Canada, with at least one biological parent with obesity (QUALITY cohort) were collected from 2005-2008, and analyzed in 2013. Sedentary behavior, light and moderate-to-vigorous physical activity were measured over 7 days using accelerometry. Leisure time computer/video game use and TV viewing over the past 7 days were self-reported. Outcomes included waist circumference, body mass index Z-score, fasting insulin, fasting glucose, triglycerides, HDL-cholesterol, C-reactive protein and a continuous cardiometabolic risk score. After adjustment for confounders, breaks in sedentary time and the number of sedentary bouts lasting 1-4 minutes were associated with reduced cardiometabolic risk score and lower BMI Z-score in both sexes (all pfasting glucose in girls, and with BMI Z-score in boys (all pobesity.

  11. Associations of Sedentary Behavior, Sedentary Bouts and Breaks in Sedentary Time with Cardiometabolic Risk in Children with a Family History of Obesity

    OpenAIRE

    Saunders, Travis John; Tremblay, Mark Stephen; Mathieu, Marie-?ve; Henderson, M?lanie; O?Loughlin, Jennifer; Tremblay, Angelo; Chaput, Jean-Philippe

    2013-01-01

    Background Although reports in adults suggest that breaks in sedentary time are associated with reduced cardiometabolic risk, these findings have yet to be replicated in children. Purpose To investigate whether objectively measured sedentary behavior, sedentary bouts or breaks in sedentary time are independently associated with cardiometabolic risk in a cohort of Canadian children aged 8?11 years with a family history of obesity. Methods Data from 286 boys and 236 girls living in Quebec, Cana...

  12. Sedentary behavior and health outcomes: an overview of systematic reviews.

    Directory of Open Access Journals (Sweden)

    Leandro Fornias Machado de Rezende

    Full Text Available 1 To synthesize the current observational evidence for the association between sedentary behavior and health outcomes using information from systematic reviews. 2 To assess the methodological quality of the systematic reviews found.Medline; Excerpta Medica (Embase; PsycINFO; and Web of Science were searched for reviews published up to September 2013. Additional publications were provided by Sedentary Behaviour Research Network members. The methodological quality of the systematic reviews was evaluated using recommended standard criteria from AMSTAR. For each review, improper use of causal language in the description of their main results/conclusion was evaluated. Altogether, 1,044 review titles were identified, 144 were read in their entirety, and 27 were included. Based on the systematic reviews with the best methodological quality, we found in children and adolescents, strong evidence of a relationship between time spent in sedentary behavior and obesity. Moreover, moderate evidence was observed for blood pressure and total cholesterol, self-esteem, social behavior problems, physical fitness and academic achievement. In adults, we found strong evidence of a relationship between sedentary behavior and all-cause mortality, fatal and non-fatal cardiovascular disease, type 2 diabetes and metabolic syndrome. In addition, there is moderate evidence for incidence rates of ovarian, colon and endometrial cancers.This overview based on the best available systematics reviews, shows that sedentary behavior may be an important determinant of health, independently of physical activity. However, the relationship is complex because it depends on the type of sedentary behavior and the age group studied. The relationship between sedentary behavior and many health outcomes remains uncertain; thus, further studies are warranted.

  13. Tribological behavior of Al-WC nano-composites fabricated by ultrasonic cavitation assisted stir-cast method

    Science.gov (United States)

    Pal, Arpan; Poria, Suswagata; Sutradhar, Goutam; Sahoo, Prasanta

    2018-03-01

    In the present study, the effects of WC nano-particles content on the microstructure, hardness, wear, and friction behavior of aluminum matrix composites are investigated. Al-WC nano composites with varying wt% of WC (0, 1, 1.5, and 2) are fabricated using ultrasonic cavitation assisted stir-cast method. The microstructure of the nano-composite samples is analyzed using optical microscopy and scanning electron microscopy. Elemental composition is determined by energy dispersive x-ray analysis. Vicker’s microhardness test is performed in different locations on the composite sample surface with a load of 50 gf and 10s dwell time. Wear and friction of the composites under dry sliding is studied using a pin-on-disk tribotester for varying normal load (10–40 N) and sliding speed (0.1–0.4 m/s). Uniform distribution of nano-WC is observed over composite surface without noticeable clustering. Reinforcement of nano-WC particles improves wear resistance and frictional behavior of the composite. Hardness is seen to increase with increase in wt% of nano-particles. Wear behavior of composites depends on formation of layers over the surface mixed with oxidized debris and counter-face particles. Wear mechanism changes from adhesion to abrasion with increase in wt% of hard nano particles.

  14. Associations of Physical Activity and Sedentary Behaviors with Dietary Behaviors among US High School Students

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    Richard Lowry

    2015-01-01

    Full Text Available Background. Physical activity (PA, sedentary behaviors, and dietary behaviors are each associated with overweight and obesity among youth. However, the associations of PA and sedentary behaviors with dietary behaviors are complex and not well understood. Purpose. To describe the associations of PA and sedentary behaviors with dietary behaviors among a representative sample of US high school students. Methods. We analyzed data from the 2010 National Youth Physical Activity and Nutrition Study (NYPANS. Using logistic regression models which controlled for sex, race/ethnicity, grade, body weight status, and weight management goals, we compared dietary behaviors among students who did and did not meet national recommendations for PA and sedentary behaviors. Results. Students who participated in recommended levels of daily PA (DPA and muscle strengthening PA (MSPA were more likely than those who did not to eat fruits and vegetables. Students who exceeded recommended limits for television (TV and computer/video game (C/VG screen time were less likely than those who did not to consume fruits and vegetables and were more likely to consume fast food and sugar-sweetened beverages. Conclusions. Researchers may want to address PA, sedentary behaviors, and dietary behaviors jointly when developing health promotion and obesity prevention programs for youth.

  15. Nicotine Dependence, Physical Activity, and Sedentary Behavior among Adult Smokers.

    Science.gov (United States)

    Loprinzi, Paul D; Walker, Jerome F

    2015-03-01

    Research has previously demonstrated an inverse association between smoking status and physical activity; however, few studies have examined the association between nicotine dependence and physical activity or sedentary behavior. This study examined the association between nicotine dependence and accelerometer-determined physical activity and sedentary behavior. Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used. A total of 851 adult (≥20 years) smokers wore an accelerometer for ≥4 days and completed the Fagerstrom Test for Nicotine Dependence scale. Regression models were used to examine the association between nicotine dependence and physical activity/sedentary behavior. After adjusting for age, gender, race-ethnicity, poverty level, hypertension, emphysema, bronchitis, body mass index (BMI), cotinine, and accelerometer wear time, smokers 50 + years of age with greater nicotine dependence engaged in more sedentary behavior (β = 11.4, P = 0.02) and less light-intensity physical activity (β = -9.6, P = 0.03) and moderate-to-vigorous physical activity (MVPA; β = -0.14, P = 0.003) than their less nicotine dependent counterparts. Older adults who are more nicotine dependent engage in less physical activity (both MVPA and light-intensity) and more sedentary behavior than their less nicotine dependent counterparts.

  16. Sedentary behavior and incident cancer: a meta-analysis of prospective studies.

    Directory of Open Access Journals (Sweden)

    Dong Shen

    Full Text Available Sedentary behavior is ubiquitous in modern adults' daily lives and it has been suggested to be associated with incident cancer. However, the results have been inconsistent. In this study, we performed a systematic review and meta-analysis of prospective cohort studies to clarify the association between sedentary behavior and incident cancer.PubMed and Embase databases were searched up to March 2014. All prospective cohort studies on the association between sedentary behavior and incident cancer were included. The summary relative risks (RRs with 95% confidence intervals (CIs were estimated using random effect model.A total of 17 prospective studies from 14 articles, including a total of 857,581 participants and 18,553 cases, were included in the analysis for sedentary behavior and risk of incident cancer. The overall meta-analysis suggested that sedentary behavior increased risk of cancer (RR = 1.20, 95%CI = 1.12-1.28, with no evidence of heterogeneity between studies (I(2 = 7.3%, P = 0.368. Subgroup analyses demonstrated that there were statistical associations between sedentary behavior and some cancer types (endometrial cancer: RR = 1.28, 95% CI = 1.08-1.53; colorectal cancer: RR = 1.30, 95%CI = 1.12-1.49; breast cancer: RR = 1.17, 95%CI = 1.03-1.33; lung cancer: RR = 1.27, 95%CI = 1.06-1.52. However, there was no association of sedentary behavior with ovarian cancer (RR = 1.26, 95%CI = 0.87-1.82, renal cell carcinoma (RR = 1.11, 95%CI = 0.87-1.41 or non-Hodgkin lymphoid neoplasms (RR = 1.09, 95%CI = 0.82-1.43.The present meta-analysis suggested that prolonged sedentary behavior was independently associated with an increased risk of incident endometrial, colorectal, breast, and lung cancers, but not with ovarian cancer, renal cell carcinoma or non-Hodgkin lymphoid neoplasms.

  17. Brazilian adults' sedentary behaviors by life domain: population-based study.

    Science.gov (United States)

    Mielke, Grégore I; da Silva, Inácio C M; Owen, Neville; Hallal, Pedro C

    2014-01-01

    There is rapidly-emerging evidence on the harmful health effects of sedentary behaviors. The aim of this paper was to quantify time in sedentary behaviors and document socio-demographic variations in different life domains among adults. A population-based survey was carried out in 2012 through face-to-face interviews with Brazilian adults aged 20+ years (N = 2,927). Information about time spent sedentary in a typical weekday was collected for five different domains (workplace, commuting, school/university, watching TV, and computer use at home). Descriptive and bivariate analyses examined variations in overall and domain-specific sedentary time by gender, age, educational attainment and socioeconomic position. On average, participants reported spending 5.8 (SD 4.5) hours per day sitting. The median value was 4.5 (interquartile range: 2.5-8) hours. Men, younger adults, those with higher schooling and from the wealthiest socioeconomic groups had higher overall sedentary scores. TV time was higher in women, older adults and among those with low schooling and socioeconomic position. Sedentary time in transport was higher in men, younger adults, and participants with high schooling and high socioeconomic position. Computer use at home was more frequent among young adults and those from high socioeconomic groups. Sitting at work was higher in those with higher schooling and from the wealthiest socioeconomic groups. Sedentary behavior at school was related inversely to age and directly to schooling. Patterns of sedentary behavior are different by life domains. Initiatives to reduce prolonged sitting among Brazilian adults will be required on multiple levels for different life domains.

  18. Brazilian adults' sedentary behaviors by life domain: population-based study.

    Directory of Open Access Journals (Sweden)

    Grégore I Mielke

    Full Text Available There is rapidly-emerging evidence on the harmful health effects of sedentary behaviors. The aim of this paper was to quantify time in sedentary behaviors and document socio-demographic variations in different life domains among adults.A population-based survey was carried out in 2012 through face-to-face interviews with Brazilian adults aged 20+ years (N = 2,927. Information about time spent sedentary in a typical weekday was collected for five different domains (workplace, commuting, school/university, watching TV, and computer use at home. Descriptive and bivariate analyses examined variations in overall and domain-specific sedentary time by gender, age, educational attainment and socioeconomic position.On average, participants reported spending 5.8 (SD 4.5 hours per day sitting. The median value was 4.5 (interquartile range: 2.5-8 hours. Men, younger adults, those with higher schooling and from the wealthiest socioeconomic groups had higher overall sedentary scores. TV time was higher in women, older adults and among those with low schooling and socioeconomic position. Sedentary time in transport was higher in men, younger adults, and participants with high schooling and high socioeconomic position. Computer use at home was more frequent among young adults and those from high socioeconomic groups. Sitting at work was higher in those with higher schooling and from the wealthiest socioeconomic groups. Sedentary behavior at school was related inversely to age and directly to schooling.Patterns of sedentary behavior are different by life domains. Initiatives to reduce prolonged sitting among Brazilian adults will be required on multiple levels for different life domains.

  19. Sedentary behaviors of adults in relation to neighborhood walkability and income.

    Science.gov (United States)

    Kozo, Justine; Sallis, James F; Conway, Terry L; Kerr, Jacqueline; Cain, Kelli; Saelens, Brian E; Frank, Lawrence D; Owen, Neville

    2012-11-01

    Sedentary (sitting) time is a newly identified risk factor for obesity and chronic diseases, which is behaviorally and physiologically distinct from lack of physical activity. To inform public health approaches to influencing sedentary behaviors, an understanding of correlates is required. Participants were 2,199 adults aged 20-66 years living in King County/Seattle, WA, and Baltimore, MD, regions, recruited from neighborhoods high or low on a "walkability index" (derived from objective built environment indicators) and having high or low median incomes. Cross-sectional associations of walkability and income with total sedentary time (measured by accelerometers and by self-report) and with self-reported time in seven specific sitting-related behaviors were examined. Neighborhood walkability and income were unrelated to measures of total sitting time. Lower neighborhood walkability was significantly associated with more driving time (difference of 18.2 min/day, p walkability was not related to total sedentary time but was related to two specific sedentary behaviors associated with risk for obesity-driving time and TV viewing time. Future research could examine how these prevalent and often prolonged sedentary behaviors mediate relationships between neighborhood walkability and overweight/obesity. Initiatives to reduce chronic disease risk among residents of both higher-and lower-income low-walkable neighborhoods should include a focus on reducing TV viewing time and other sedentary behaviors and enacting policies that can lead to the development or redevelopment of more-walkable neighborhoods. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

  20. Taxonomy-based content analysis of sedentary behavior questionnaires: A systematic review

    Science.gov (United States)

    Rivière, Fabien; Aubert, Salomé; Omorou, Abdou Yacoubou; Ainsworth, Barbara E.

    2018-01-01

    Background Health effects of sedentary behaviors (SB) may vary depending on their characteristics such as type, purpose, duration, and intensity of the behavior. While a growing number of questionnaires assess sedentary behaviors, it is unclear which characteristics of SB are measured. The aim of this review was to examine the content of self-report SB questionnaires. Methods Three databases were searched for sedentary behavior questionnaires published before January 1st, 2016. Based on the inclusion criteria, 82 articles out of 1369 were retrieved for a total of 60 questionnaires. For each questionnaire, the sedentary behavior characteristics identified were reported and analyzed. Results Most of the questionnaires assessed the time (n = 60), posture (n = 54), purpose (n = 46) and the types (n = 45) of SB performed. Fewer questionnaires assessed the environment (n = 20) social context (n = 11), status (n = 2), and associated behaviors (n = 2) related to sedentary behaviors. All the questionnaires except two assessed time spent in SB with 17 assessing frequency and 6 assessing breaks in SB. The most frequent characteristics identified in the questionnaires were the categories of sitting (90%), a day (95%), watching television (65%) and using a computer (55%). Many characteristics of SB were not measured. Conclusions By knowing the breadth of SB included in questionnaires, this review provides support to shape the design of new questionnaires designed to reduce the gaps in measuring sedentary behaviors. PMID:29509791

  1. Discrete features of sedentary behavior impact cardiometabolic risk factors.

    Science.gov (United States)

    Lyden, Kate; Keadle, Sarah Kozey; Staudenmayer, John; Braun, Barry; Freedson, Patty S

    2015-05-01

    Sedentary behavior is linked to numerous poor health outcomes. This study aims to determine the effects of 7 d of increased sitting on markers of cardiometabolic risk among free-living individuals. Ten recreationally active participants (>150 min of moderate-intensity physical activity per week; mean ± SD age, 25.2 ± 5.7 yr; mean ± SD body mass index, 24.9 ± 4.3 kg·m(-2)) completed a 7-d baseline period and a 7-d sedentary condition in their free-living environment. At baseline, participants maintained normal activity. After baseline, participants completed a 7-d sedentary condition. Participants were instructed to sit as much as possible, to limit standing and walking, and to refrain from structured exercise and leisure time physical activity. ActivPAL monitor was used to assess sedentary behavior and physical activity. Fasting lipids, glucose, and insulin were measured, and oral glucose tolerance test was performed after baseline and sedentary condition. In comparison to baseline, total sedentary time (mean Δ, 14.9%; 95% CI, 10.2-19.6) and time in prolonged/uninterrupted sedentary bouts significantly increased, whereas the rate of breaks from sedentary time was significantly reduced (mean Δ, 21.4%; 95% CI, 6.9-35.9). For oral glucose tolerance test, 2-h plasma insulin (mean Δ, 38.8 μU·mL(-1); 95% CI, 10.9-66.8) and area under the insulin curve (mean Δ, 3074.1 μU·mL(-1) per 120 min; 95% CI, 526.0-5622.3) were significantly elevated after the sedentary condition. Lipid concentrations did not change. Change in 2-h insulin was negatively associated with change in light-intensity activity (r = -0.62) and positively associated with change in time in sitting bouts longer than 30 min (r = 0.82) and 60 min (r = 0.83). Increased free-living sitting negatively impacts markers of cardiometabolic health, and specific features of sedentary behavior (e.g., time in prolonged sitting bouts) may be particularly important.

  2. Exposure to simultaneous sedentary behavior domains and sociodemographic factors associated in public servants

    Directory of Open Access Journals (Sweden)

    Fernanda Cerveira Fronza

    2017-11-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2017v19n4p469   Exposure to sedentary behavior may contribute to health problems. This study aimed to estimate the prevalence of exposure to simultaneous sedentary behavior domains and verify associated sociodemographic characteristics among technical and administrative servers of a Brazilian university. This is a cross-sectional epidemiological study carried out with 623 technical and administrative servers. Sedentary behavior was identified through a questionnaire in the following domains: commuting (active / passive, sitting time at work, daily time spent watching television and computer use (≥3 hours / day. Sociodemographic variables were age, sex and educational level. The prevalence of servers that had one, two, three and four simultaneous sedentary behavior was 28.4%, 43.2%, 22.5% and 4.3%, respectively. Women were more likely to have three sedentary behavior simultaneously (OR = 1.61, CI 95% = 1.02, 2.56. Servers with 9-11 years of schooling were less exposed to two (OR = 0.27, CI 95% = 0.17, 0.44, three (OR = 0.39, CI 95% = 0.23, 0.66 and four (OR = 0.22, CI 95% = 0.07; 0.69 sedentary behavior simultaneously and those over 12 years of schooling were less likely of having two (OR = 0.22, CI 95% = 0.10; 0.49 and three (OR = 0.15, CI 95% = 0.05, 0.46 sedentary behavior simultaneously. More than half of servers have two sedentary behavior during the week. Having sedentary behavior in more than one domain simultaneously was associated with sex and educational level.

  3. Schoolyard Characteristics, Physical Activity, and Sedentary Behavior

    DEFF Research Database (Denmark)

    Van Kann, Dave H H; de Vries, Sanne I; Schipperijn, Jasper

    2016-01-01

    BACKGROUND: Physical activity (PA) is decreasing among children, while sedentary behavior (SB) is increasing. Schoolyards seem suitable settings to influence children's PA behavior. This study investigated the associations between schoolyard characteristics and moderate-to-vigorous physical activ...

  4. Office workers' objectively measured sedentary behavior and physical activity during and outside working hours.

    Science.gov (United States)

    Clemes, Stacy A; O'Connell, Sophie E; Edwardson, Charlotte L

    2014-03-01

    To examine objectively determined sedentary behavior and physical activity (PA) during and outside working hours in full-time office workers. A total of 170 participants wore an ActiGraph GT1M accelerometer for 7 days. Time spent sedentary (working hours and nonworking hours) and nonworkdays. Participants accumulated significantly higher levels of sedentary behavior (68% vs 60%) and lower levels of light-intensity activity (28% vs 36%) on workdays in comparison with nonworkdays. Up to 71% of working hours were spent sedentary. Individuals who were most sedentary at work were also more sedentary outside work. Those who are most sedentary at work do not compensate by increasing their PA or reducing their sedentary time outside work. Occupational interventions should address workplace and leisure-time sedentary behavior.

  5. Sedentary behavior and dietary intake in children, adolescents, and adults. A systematic review.

    Science.gov (United States)

    Pearson, Natalie; Biddle, Stuart J H

    2011-08-01

    Sedentary behavior is implicated in youth and adult overweight and obesity. However, the relationship between sedentary behavior and weight status is often small or inconsistent, with few studies controlling for confounding factors such as diet and physical activity. Diet has been hypothesized to covary with some sedentary behaviors. It is opportune, therefore, to review whether dietary intake is associated with sedentary behavior in young people and adults. This may allow for better interpretation of the diversity of findings concerning sedentary behavior and weight status. Published English-language studies were located from computerized and manual searches in early 2010. Included studies were observational studies assessing an association between at least one sedentary behavior and at least one aspect of dietary intake in children (aged 18 years). Fifty-three studies, totaling 111 independent samples, were eligible for this review. Sedentary behavior in children (n=19, independent samples=24), adolescents (n=26, independent samples=72), and adults (n=11, independent samples=14) appears to be clearly associated with elements of a less healthy diet including lower fruit and vegetable consumption; higher consumption of energy-dense snacks, drinks, and fast foods; and higher total energy intake. Strengths of association were mainly in the small-to-moderate range. The association drawn mainly from cross-sectional studies is that sedentary behavior, usually assessed as screen time and predominantly TV viewing, is associated with unhealthy dietary behaviors in children, adolescents, and adults. Interventions need to be developed that target reductions in sedentary time to test whether diet also changes. Copyright © 2011 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  6. Physical inactivity and sedentary behavior: Overlooked risk factors in autoimmune rheumatic diseases?

    Science.gov (United States)

    Pinto, Ana Jéssica; Roschel, Hamilton; de Sá Pinto, Ana Lúcia; Lima, Fernanda Rodrigues; Pereira, Rosa Maria Rodrigues; Silva, Clovis Artur; Bonfá, Eloisa; Gualano, Bruno

    2017-07-01

    This review aims to (1) summarize the estimates of physical inactivity and sedentary behavior in autoimmune rheumatic diseases; (2) describe the relationship between physical (in)activity levels and disease-related outcomes; (3) contextualize the estimates and impact of physical inactivity and sedentary behavior in autoimmune diseases compared to other rheumatic diseases and chronic conditions; and (4) discuss scientific perspectives around this theme and potential clinical interventions to attenuate these preventable risk factors. We compiled evidence to show that estimates of physical inactivity and sedentary behavior in autoimmune rheumatic diseases are generally comparable to other rheumatic diseases as well as to other chronic conditions (e.g., type 2 diabetes, cardiovascular diseases, and obesity), in which a lack of physical activity and excess of sedentary behavior are well-known predictors of morbimortality. In addition, we also showed evidence that both physical inactivity and sedentary behavior may be associated with poor health-related outcomes (e.g., worse disease symptoms and low functionality) in autoimmune rheumatic diseases. Thus, putting into practice interventions to make the patients "sit less and move more", particularly light-intensity activities and/or breaking-up sedentary time, is a simple and prudent therapeutic approach to minimize physical inactivity and sedentary behavior, which are overlooked yet modifiable risk factors in the field of autoimmune rheumatic diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Synthesis and Multi Scale Tribological Behavior of WC-Co/Nanodiamond Nanocomposites.

    Science.gov (United States)

    Nieto, Andy; Jiang, Lin; Kim, Jaekang; Kim, Dae-Eun; Schoenung, Julie M

    2017-08-01

    Nanodiamonds (ND) present a unique combination of desirable mechanical, functional, and chemical characteristics that are ideally suited for reinforcing and enhancing the wear resistance of carbide based materials. Tungsten carbide cobalt (WC-Co) matrix nanocomposites reinforced with varying amounts of ND (2 - 10 vol.%) were synthesized here by spark plasma sintering. The rapid thermal consolidation route enabled attainment of dense samples with a significant retention of the metastable diamond phase. NDs affected the microstructural evolution, chemistry, and mechanical properties of WC-Co. Macroscale reciprocating pin-on-disk tests were conducted to assess wear behavior under conditions relevant to service environments, e.g., high cycles and high contact pressure. Microscale tribological properties were assessed using microscratch tests in order to investigate the intrinsic effects of ND on the localized mechanical and tribological response of WC-Co-ND composites. The incorporation of 10 vol.% ND enhanced wear resistance at both the micro- and macroscale, by 28% and 35%, respectively.

  8. Objectively measured sedentary behavior in preschool children: comparison between Montessori and traditional preschools.

    Science.gov (United States)

    Byun, Wonwoo; Blair, Steven N; Pate, Russell R

    2013-01-03

    This study aimed to compare the levels of objectively-measured sedentary behavior in children attending Montessori preschools with those attending traditional preschools. The participants in this study were preschool children aged 4 years old who were enrolled in Montessori and traditional preschools. The preschool children wore ActiGraph accelerometers. Accelerometers were initialized using 15-second intervals and sedentary behavior was defined as Montessori preschools, after adjusting for selected potential correlates of preschoolers' sedentary behavior. Children attending Montessori preschools spent less time in sedentary behavior than those attending traditional preschools during the in-school (44.4. min/hr vs. 47.1 min/hr, P = 0.03), after-school (42.8. min/hr vs. 44.7 min/hr, P = 0.04), and total-day (43.7 min/hr vs. 45.5 min/hr, P = 0. 009) periods. School type (Montessori or traditional), preschool setting (private or public), socio-demographic factors (age, gender, and socioeconomic status) were found to be significant predictors of preschoolers' sedentary behavior. Levels of objectively-measured sedentary behavior were significantly lower among children attending Montessori preschools compared to children attending traditional preschools. Future research should examine the specific characteristics of Montessori preschools that predict the lower levels of sedentary behavior among children attending these preschools compared to children attending traditional preschools.

  9. Accounting for Sitting and Moving: An Analysis of Sedentary Behavior in Mass Media Campaigns.

    Science.gov (United States)

    Knox, Emily; Biddle, Stuart; Esliger, Dale W; Piggin, Joe; Sherar, Lauren

    2015-09-01

    Mass media campaigns are an important tool for promoting health-related physical activity. The relevance of sedentary behavior to public health has propelled it to feature prominently in health campaigns across the world. This study explored the use of messages regarding sedentary behavior in health campaigns within the context of current debates surrounding the association between sedentary behavior and health, and messaging strategies to promote moderate-to-vigorous physical activity (MVPA). A web-based search of major campaigns in the United Kingdom, United States, Canada, and Australia was performed to identify the main campaign from each country. A directed content analysis was then conducted to analyze the inclusion of messages regarding sedentary behavior in health campaigns and to elucidate key themes. Important areas for future research were illustrated. Four key themes from the campaigns emerged: clinging to sedentary behavior guidelines, advocating reducing sedentary behavior as a first step on the activity continuum and the importance of light activity, confusing the promotion of MVPA, and the demonization of sedentary behavior. Strategies for managing sedentary behavior as an additional complicating factor in health promotion are urgently required. Lessons learned from previous health communication campaigns should stimulate research to inform future messaging strategies.

  10. Associations of sedentary behavior, sedentary bouts and breaks in sedentary time with cardiometabolic risk in children with a family history of obesity.

    Directory of Open Access Journals (Sweden)

    Travis John Saunders

    Full Text Available Although reports in adults suggest that breaks in sedentary time are associated with reduced cardiometabolic risk, these findings have yet to be replicated in children.To investigate whether objectively measured sedentary behavior, sedentary bouts or breaks in sedentary time are independently associated with cardiometabolic risk in a cohort of Canadian children aged 8-11 years with a family history of obesity.Data from 286 boys and 236 girls living in Quebec, Canada, with at least one biological parent with obesity (QUALITY cohort were collected from 2005-2008, and analyzed in 2013. Sedentary behavior, light and moderate-to-vigorous physical activity were measured over 7 days using accelerometry. Leisure time computer/video game use and TV viewing over the past 7 days were self-reported. Outcomes included waist circumference, body mass index Z-score, fasting insulin, fasting glucose, triglycerides, HDL-cholesterol, C-reactive protein and a continuous cardiometabolic risk score.After adjustment for confounders, breaks in sedentary time and the number of sedentary bouts lasting 1-4 minutes were associated with reduced cardiometabolic risk score and lower BMI Z-score in both sexes (all p<0.05. The number of sedentary bouts lasting 5-9 minutes was negatively associated with waist circumference in girls only, while the number of bouts lasting 10-14 minutes was positively associated with fasting glucose in girls, and with BMI Z-score in boys (all p<0.05. Leisure time computer/video game use was associated with increased cardiometabolic risk score and waist circumference in boys, while TV viewing was associated with increased cardiometabolic risk, waist circumference, and BMI Z-score in girls (all p<0.05.These results suggest that frequent interruptions in sedentary time are associated with a favourable cardiometabolic risk profile and highlight the deleterious relationship between screen time and cardiometabolic risk among children with a family

  11. Physical Activity, Sedentary Behavior, and Dietary Patterns among Children.

    Science.gov (United States)

    Gubbels, Jessica S; van Assema, Patricia; Kremers, Stef P J

    2013-06-01

    Energy balance-related behavioral patterns find their origin in early childhood. The current paper provides an overview of studies that have examined such behavioral patterns, i.e., the clustering of dietary behaviors, physical activity, and/or sedentary behavior. The paper discusses the importance of examining energy balance-related behavioral patterns in children, outlines methods to examine these patterns, and provides examples of patterns that have been found (e.g., the universal sedentary-snacking and healthy intake patterns, as well as more unique or local patterns), child and parental characteristics predicting such patterns (e.g., child gender and maternal educational level), and the relationship of these patterns with overweight and related measures.

  12. Empowering Sedentary Adults to Reduce Sedentary Behavior and Increase Physical Activity Levels and Energy Expenditure: A Pilot Study

    OpenAIRE

    Barwais, Faisal A.; Cuddihy, Thomas F.

    2015-01-01

    Objective: The purpose of this study was to assess the effectiveness of a 4-week intervention in which an online personal activity monitor (Gruve-Technologies™) was used to reduce sedentary behavior among sedentary adults. Method: Eighteen, sedentary adult volunteers (12 men, six women, mean age 29 ± 4.0 years) were recruited to participate in the study. Time spent in sedentary activities and light-, moderate-, and vigorous-intensity physical activity and energy expenditure were assessed duri...

  13. Friendship networks and physical activity and sedentary behavior among youth: a systematized review.

    Science.gov (United States)

    Sawka, Keri Jo; McCormack, Gavin R; Nettel-Aguirre, Alberto; Hawe, Penelope; Doyle-Baker, Patricia K

    2013-12-01

    Low levels of physical activity and increased participation in sedentary leisure-time activities are two important obesity-risk behaviors that impact the health of today's youth. Friend's health behaviors have been shown to influence individual health behaviors; however, current evidence on the specific role of friendship networks in relation to levels of physical activity and sedentary behavior is limited. The purpose of this review was to summarize evidence on friendship networks and both physical activity and sedentary behavior among children and adolescents. After a search of seven scientific databases and reference scans, a total of thirteen articles were eligible for inclusion. All assessed the association between friendship networks and physical activity, while three also assessed sedentary behavior. Overall, higher levels of physical activity among friends are associated with higher levels of physical activity of the individual. Longitudinal studies reveal that an individual's level of physical activity changes to reflect his/her friends' higher level of physical activity. Boys tend to be influenced by their friendship network to a greater extent than girls. There is mixed evidence surrounding a friend's sedentary behavior and individual sedentary behavior. Friends' physical activity level appears to have a significant influence on individual's physical activity level. Evidence surrounding sedentary behavior is limited and mixed. Results from this review could inform effective public health interventions that harness the influence of friends to increase physical activity levels among children and adolescents.

  14. A Two-Layer Method for Sedentary Behaviors Classification Using Smartphone and Bluetooth Beacons.

    Science.gov (United States)

    Cerón, Jesús D; López, Diego M; Hofmann, Christian

    2017-01-01

    Among the factors that outline the health of populations, person's lifestyle is the more important one. This work focuses on the caracterization and prevention of sedentary lifestyles. A sedentary behavior is defined as "any waking behavior characterized by an energy expenditure of 1.5 METs (Metabolic Equivalent) or less while in a sitting or reclining posture". To propose a method for sedentary behaviors classification using a smartphone and Bluetooth beacons considering different types of classification models: personal, hybrid or impersonal. Following the CRISP-DM methodology, a method based on a two-layer approach for the classification of sedentary behaviors is proposed. Using data collected from a smartphones' accelerometer, gyroscope and barometer; the first layer classifies between performing a sedentary behavior and not. The second layer of the method classifies the specific sedentary activity performed using only the smartphone's accelerometer and barometer data, but adding indoor location data, using Bluetooth Low Energy (BLE) beacons. To improve the precision of the classification, both layers implemented the Random Forest algorithm and the personal model. This study presents the first available method for the automatic classification of specific sedentary behaviors. The layered classification approach has the potential to improve processing, memory and energy consumption of mobile devices and wearables used.

  15. Source and Size of Social Support Network on Sedentary Behavior Among Older Adults.

    Science.gov (United States)

    Loprinzi, Paul D; Crush, Elizabeth A

    2018-01-01

    To examine the association of source of social support and size of social support network on sedentary behavior among older adults. Cross-sectional. National Health and Nutrition Examination Survey 2003 to 2006. 2519 older adults (60+ years). Sedentary behavior was assessed via accelerometry over a 7-day period. Social support was assessed via self-report. Sources evaluated include spouse, son, daughter, sibling, neighbor, church member, and friend. Regarding size of social network, participants were asked, "In general, how many close friends do you have?" Multivariable linear regression. After adjustment, there was no evidence of an association between the size of social support network and sedentary behavior. With regard to specific sources of social support, spousal social support was associated with less sedentary behavior (β = -11.6; 95% confidence interval: -20.7 to -2.5), with evidence to suggest that this was only true for men. Further, an inverse association was observed between household size and sedentary behavior, with those having a greater number of individuals in the house having lower levels of sedentary behavior. These associations occurred independent of moderate-to-vigorous physical activity, age, gender, race-ethnicity, measured body mass index, total cholesterol, self-reported smoking status, and physician diagnosis of congestive heart failure, coronary artery disease, stroke, cancer, hypertension, or diabetes. Spouse-specific emotion-related social support (particularly for men) and household size were associated with less sedentary behavior.

  16. Sedentary behaviours and obesity in adults: the Cardiovascular Risk in Young Finns Study

    Science.gov (United States)

    Heinonen, I; Helajärvi, H; Pahkala, K; Heinonen, O J; Hirvensalo, M; Pälve, K; Tammelin, T; Yang, X; Juonala, M; Mikkilä, V; Kähönen, M; Lehtimäki, T; Viikari, J; Raitakari, O T

    2013-01-01

    Objective Sedentary behaviour may contribute to the development of obesity. We investigated the relations between different types of sedentary behaviour and adiposity markers in a well-characterised adult population after controlling for a wide range of potential confounders. Design Cross-sectional study. Setting The Cardiovascular Risk in Young Finns Multicenter Study. Participants Sedentary time (TV viewing, computer time, reading, music/radio listening and other relaxation) was assessed with a questionnaire for 1084 women and 909 men aged 30–45 years. Other study variables included occupational and leisure-time physical activity, sleep duration, socioeconomic status, smoking, alcohol consumption, energy intake, adherence to the recommended diet, multiple individual food items, age and genetic variants associated with body mass index (BMI). Primary outcome measures BMI in kg/m2 and waist circumference (WC in cm). Results Of the different sedentary behaviour types, TV viewing was most consistently related to higher BMI and WC, both in men and women. One additional daily TV hour was associated with a 1.81±0.44 cm larger WC in women and 2 cm±0.44 cm in men (both psedentary behaviour remained associated with adiposity indices only in women. Conclusions Out of the different types of sedentary behaviour, TV viewing was most consistently associated with adiposity markers in adults. Partial dilution of these associations after adjustments for covariates suggests that the obesogenic effects of TV viewing are partly mediated by other lifestyle factors. PMID:23794543

  17. The health indicators associated with screen-based sedentary behavior among adolescent girls: a systematic review.

    Science.gov (United States)

    Costigan, Sarah A; Barnett, Lisa; Plotnikoff, Ronald C; Lubans, David R

    2013-04-01

    Evidence suggests sitting time is independently associated with a range of health issues in adults, yet the relationship between sedentary behavior and health indicators in young people is less clear. Age-related increases in sedentary behavior are well-documented; the behavioral patterns of adolescent girls are of particular concern. More than one third of adolescent girls' sedentary behavior time is accumulated through use of recreational screen-based behaviors. The objective of this review was to investigate the association between recreational screen-based sedentary behavior and the physical, behavioral, and psychosocial health indicators for adolescent girls. A secondary objective was to identify studies that have adjusted sedentary behavior indicators for physical activity. A structured electronic search of all publication years (through December 2011) was conducted to identify studies in: CINAHL, Communications and Mass Media Complete, ERIC, MEDLINE with Full Text, PsycINFO, and SPORTDiscus with Full Text. Included publications were observational and interventional studies involving adolescent girls (12-18 years) that examined associations between screen-based, sedentary behavior and health indicators (physical, psychosocial, and/or behavioral). The search identified 33 studies that evaluated health indicators of screen-based sedentary behaviors among adolescent girls. Strong evidence for a positive association between screen-based sedentary behavior and weight status was found. A positive association was observed between screen-time and sleep problems, musculoskeletal pain and depression. Negative associations were identified between screen time and physical activity/fitness, screen time and psychological well-being, and screen time and social support. The relationship between screen-based sedentary behavior and diet quality was inconclusive. Less than half of the studies adjusted sedentary behavior indicators for physical activity. Screen-based sedentary

  18. "Pokémon Go!" May Promote Walking, Discourage Sedentary Behavior in College Students.

    Science.gov (United States)

    Barkley, Jacob E; Lepp, Andrew; Glickman, Ellen L

    2017-06-01

    To assess self-reported walking and sedentary behavior in young adults before and after downloading "Pokémon Go!". In September 2016, a sample of 358 (19.8 ± 2.1 years old, n = 187 females) college students who had downloaded "Pokémon Go!" on their cellular telephones (i.e., cell phones) were surveyed for weekly walking and sedentary behavior via the International Physical Activity Questionnaire. A single interview was administered to participants who estimated their walking and sedentary behavior at three time points: the week immediately preceding their download of "Pokémon Go!" (Baseline), the first week after downloading the game (Time 1), and the week the survey was completed (Time 2). Differences in self-reported physical activity and sedentary behavior across the three time points and across the two genders were compared via analyses of variance. There was a significant main effect of time (F ≥ 49.3, P ≤ 0.001) for walking and sedentary behavior. Participants reported greater (t ≥ 9.5, P games hold promise as technology that may promote physical activity and discourage sedentary behavior.

  19. A study on erosive wear behavior of HVOF sprayed nanostructured WC-CoCr coatings

    International Nuclear Information System (INIS)

    Thakur, Lalit; Arora, Navneet

    2013-01-01

    WC-CoCr cermet coatings were deposited on stainless steel substrate using high-velocity oxy-fuel (HVOF) thermal spray process. The coatings were developed with two different thermal spray powders: one has WC grains of conventional micron size and the other is composed of nanosized (near-nanostructured) grains. HVOF spraying was assisted with in-flight particle temperature and velocity measurement system to control the process parameters that have resulted in quality coatings. Cavitation erosion testing was performed using a vibratory test apparatus based on ASTM standard G32-98. Surface morphology of powders and coatings was examined using the FESEM images, and phase identification was performed by XRD analysis. The erosion behavior of coatings and mechanism of material removal was discussed by examining the microstructure images of worn-out surfaces. WC-CoCr cermet coating deposited with nanosized WC grains exhibited higher cavitation erosion resistance as compared to conventional coating.

  20. A study on erosive wear behavior of HVOF sprayed nanostructured WC-CoCr coatings

    Energy Technology Data Exchange (ETDEWEB)

    Thakur, Lalit; Arora, Navneet [Indian Institute of Technology Roorkee, Roorkee (India)

    2013-05-15

    WC-CoCr cermet coatings were deposited on stainless steel substrate using high-velocity oxy-fuel (HVOF) thermal spray process. The coatings were developed with two different thermal spray powders: one has WC grains of conventional micron size and the other is composed of nanosized (near-nanostructured) grains. HVOF spraying was assisted with in-flight particle temperature and velocity measurement system to control the process parameters that have resulted in quality coatings. Cavitation erosion testing was performed using a vibratory test apparatus based on ASTM standard G32-98. Surface morphology of powders and coatings was examined using the FESEM images, and phase identification was performed by XRD analysis. The erosion behavior of coatings and mechanism of material removal was discussed by examining the microstructure images of worn-out surfaces. WC-CoCr cermet coating deposited with nanosized WC grains exhibited higher cavitation erosion resistance as compared to conventional coating.

  1. The Potential Impact of Displacing Sedentary Time in Adults with Type 2 Diabetes

    Science.gov (United States)

    FALCONER, CATHERINE L.; PAGE, ANGIE S.; ANDREWS, ROB C.; COOPER, ASHLEY R.

    2015-01-01

    ABSTRACT Purpose Sedentary time, in particular, prolonged unbroken sedentary time, is detrimental to health and displaces time spent in either light or moderate intensity physical activity. This cross-sectional study aimed to identify the potential impact of reallocating time from sedentary behaviors to more active behaviors on measures of body composition and metabolic health in people with type 2 diabetes. Methods Participants were 519 adults with newly diagnosed type 2 diabetes who had been recruited to the Early Activity in Diabetes (Early ACTID) randomized controlled trial. Waist-worn accelerometers were used to obtain objective measurement of sedentary time, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) at baseline alongside clinical measurements and fasting blood samples to determine cholesterol, triglycerides, HOMA-IR, and glucose. Isotemporal substitution modeling was performed to determine the potential impact of reallocating 30 min of sedentary time accumulated in a single bout (long bout) with 30 min of interrupted sedentary time, LPA, or MVPA. Results Sedentary time accounted for 65% of the waking day, of which 45% was accumulated in prolonged (≥30 min) bouts. Reallocation of 30 min of long-bout sedentary time with 30 min of short-bout sedentary time was associated with lower body mass index (BMI) (adjusted β, −0.60; 95% confidence interval [CI], −1.00, −0.21) and waist circumference (WC) (adjusted β, −1.16; 95% CI, −2.08, −0.25). Stronger effects were seen for LPA and MVPA. Reallocation of 30 min of long-bout sedentary time with LPA was associated with higher HDL-cholesterol (adjusted β, 0.02; 95% CI, 0.00–0.03 mmol·L−1). Conclusions Encouraging adults with newly diagnosed type 2 diabetes to break up prolonged periods of sedentary time may be an effective strategy for improving body composition and metabolic health. PMID:26378943

  2. Relation between high leisure-time sedentary behavior and low functionality in older adults

    Directory of Open Access Journals (Sweden)

    Giovana Navarro Bertolini

    2016-02-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n6p713   Sedentary behavior refers to activities with low energy expenditure, usually performed in sitting or lying positions, and includes behavior belonging to the current lifestyle, such as watching television. In the course of aging, this activity is performed for longer periods by individuals on a daily basis. This is worrying, since aging associated with sedentary behavior accentuates functionality decline. The aim of this study was to analyze the relationship between high leisure-time sedentary behavior and low functionality in older adults. The sample consisted of 375 older adults aged 60-97 years (70 ± 7 years, and of these, 114 (30% were men and 261 (70% women. Functionality was assessed by two functional tests and information related to sedentary behavior was obtained using the self-reported physical activity questionnaire proposed by Baecke et al. The chi-square test was used to verify the association between sedentary behavior and functionality, and binary logistic regression analysis was used to build the multiple model. Older individuals with high leisure-time sedentary behavior were more likely to have low functionality [OR 2.57; 95% CI 1.40 to 4.71] and [OR 2.35; 95% CI 1.29 to 4.29] regardless of gender, age, smoking, osteoporosis, arthritis / osteoarthritis, low back pain and physical activity. Extended permanence in sedentary behavior was associated with low functionality in older subjects. Preventive measures to stimulate the practice of physical activities and encourage the reduction of time spent in sedentary activities such as watching television should be adopted by health professionals in an attempt to maintain functionality among older adults.

  3. Nicotine dependence, physical activity, and sedentary behavior among adult smokers

    OpenAIRE

    Paul D Loprinzi; Jerome F Walker

    2015-01-01

    Background: Research has previously demonstrated an inverse association between smoking status and physical activity; however, few studies have examined the association between nicotine dependence and physical activity or sedentary behavior. Aim: This study examined the association between nicotine dependence and accelerometer-determined physical activity and sedentary behavior. Materials and Methods: Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used....

  4. Application of the transtheoretical model to sedentary behaviors and its association with physical activity status.

    Directory of Open Access Journals (Sweden)

    Ho Han

    Full Text Available The Transtheoretical Model (TTM is a successful framework for guiding behavior change programs for several health behaviors, yet its application to reduce of sedentary behavior has been neglected. In addition, no data exist regarding the association between determinants of sedentary behaviors based on the TTM and physical activity behavior. The purpose of this study was to investigate college students' stages of motivational readiness to avoid sedentary behaviors and relevant psychological determinants using newly developed TTM questionnaires and to identify the association between current physical activity and sedentary behaviors based on TTM constructs.Data were obtained from 225 college students enrolled in health education and physical education courses. Participants completed a package of questionnaires including validated TTM, physical activity and sitting time questionnaires. Participants also wore an accelerometer for seven consecutive days. MANOVAs were conducted to determine mean differences in psychological constructs across the TTM stages, and Chi-square tests and Spearman correlation were used to evaluate the associations between current physical activity and sedentary behavior.A majority of the participants were in the sedentary stages, and men and women differed in proportion of individuals in the stages (78.0% vs. 68.1%, respectively. The gender difference was also found in use of the processes of change. In general, the mean scores of the TTM constructs increased as the stages progressed. No significant associations were found between the TTM constructs for sedentary behavior and current physical activity levels (p>0.05.A high proportion of college students were in sedentary stages regardless of physical activity levels, but different distributions in men and women. Participants in earlier stages were less likely to utilize the TTM constructs to reduce sedentary behaviors than those in later stages. A lack of association between

  5. Comparison of Sedentary Behaviors between Children with Autism Spectrum Disorders and Typically Developing Children

    Science.gov (United States)

    Must, Aviva; Phillips, Sarah M.; Curtin, Carol; Anderson, Sarah E.; Maslin, Melissa; Lividini, Keith; Bandini, Linda G.

    2014-01-01

    Time spent in sedentary behavior is largely due to time spent engaged with electronic screen media. Little is known about the extent to which sedentary behaviors for children with autism spectrum disorder differ from typically developing children. We used parental report to assess and compare time spent in sedentary behaviors for 53 children with…

  6. Objectively measured sedentary behavior in preschool children: comparison between Montessori and traditional preschools

    Directory of Open Access Journals (Sweden)

    Byun Wonwoo

    2013-01-01

    Full Text Available Abstract Background This study aimed to compare the levels of objectively-measured sedentary behavior in children attending Montessori preschools with those attending traditional preschools. Methods The participants in this study were preschool children aged 4 years old who were enrolled in Montessori and traditional preschools. The preschool children wore ActiGraph accelerometers. Accelerometers were initialized using 15-second intervals and sedentary behavior was defined as Results Children attending Montessori preschools spent less time in sedentary behavior than those attending traditional preschools during the in-school (44.4. min/hr vs. 47.1 min/hr, P = 0.03, after-school (42.8. min/hr vs. 44.7 min/hr, P = 0.04, and total-day (43.7 min/hr vs. 45.5 min/hr, P = 0. 009 periods. School type (Montessori or traditional, preschool setting (private or public, socio-demographic factors (age, gender, and socioeconomic status were found to be significant predictors of preschoolers’ sedentary behavior. Conclusions Levels of objectively-measured sedentary behavior were significantly lower among children attending Montessori preschools compared to children attending traditional preschools. Future research should examine the specific characteristics of Montessori preschools that predict the lower levels of sedentary behavior among children attending these preschools compared to children attending traditional preschools.

  7. Development of sedentary behavior across childhood and adolescence: longitudinal analysis of the Gateshead Millennium Study

    OpenAIRE

    Janssen, Xanne; Mann, Kay D.; Basterfield, Laura; Parkinson, Kathryn N.; Pearce, Mark S.; Reilly, Jessica K.; Adamson, Ashley J.; Reilly, John J.

    2016-01-01

    Background In many parts of the world policy and research interventions to modify sedentary behavior of children and adolescents are now being developed. However, the evidence to inform these interventions (e.g. how sedentary behavior changes across childhood and adolescence) is limited. This study aimed to assess longitudinal changes in sedentary behavior, and examine the degree of tracking of sedentary behavior from age 7y to 15y. Methods Participants were part of the Gateshead Millennium S...

  8. Why Do Children Engage in Sedentary Behavior? Child- and Parent-Perceived Determinants.

    Science.gov (United States)

    Hidding, Lisan M; Altenburg, Teatske M; van Ekris, Evi; Chinapaw, Mai J M

    2017-06-22

    Todays children spend a large amount of their time sedentary. There is limited evidence on the determinants of sedentary behavior in children, and qualitative studies are especially lacking. Therefore, this study aimed to explore determinants of children's sedentary behavior from the child- and parent perspective. Qualitative data were collected during concept mapping sessions with four groups of 11-13 years old children ( n = 38) and two online sessions with parents ( n = 21). Children and parents generated sedentary behavior motives, sorted related motives, and rated their importance in influencing children's sedentary time. Next, multidimensional scaling and hierarchical cluster analysis was performed to create clusters of motives resulting in a concept map. Finally, the researchers named the clusters in the concept map. Concept maps of children yielded eight to ten perceived determinants, and concept maps of parents six to seven. Children and parents identified six similar potential determinants, and both rated as important: Sitting because… "it is the norm (I have to)", and "I can work/play better that way". In addition, children rated "there is nobody to play with" as an important potential determinant for engaging in sedentary behavior. The most important child- and parent perceived determinants were related to the social/cultural and physical environment, indicating that these are promising targets for future interventions.

  9. Physical activity and sedentary behavior patterns are associated with selected adolescent health risk behaviors.

    Science.gov (United States)

    Nelson, Melissa C; Gordon-Larsen, Penny

    2006-04-01

    Little is known about how physical activity (PA), sedentary behavior, and various adolescent health risk behaviors are associated. The objective of this study was to examine relationships between PA and sedentary behavior patterns and an array of risk behaviors, including leading causes of adolescent morbidity/mortality. Nationally representative self-reported data were collected (National Longitudinal Study of Adolescent Health; wave I: 1994-1995; II: 1996; N = 11957). Previously developed and validated cluster analyses identified 7 homogeneous groups of adolescents sharing PA and sedentary behaviors. Poisson regression predicted the relative risk of health risk behaviors, other weekly activities, and self-esteem across the 7 PA/sedentary behavior clusters controlling for demographics and socioeconomic status. Main outcome measures were adolescent risk behaviors (eg, truancy, cigarette smoking, sexual intercourse, delinquency), other weekly activities (eg, work, academic performance, sleep), self-esteem. Relative to high television (TV) and video viewers, adolescents in clusters characterized by skating and video gaming, high overall sports and sports participation with parents, using neighborhood recreation center, strict parental control of TV, reporting few activities overall, and being active in school were less likely to participate in a range of risky behaviors, ranging from an adjusted risk ratio (ARR) of 0.42 (outcome: illegal drug use, cluster: strict parental control of TV) to 0.88 (outcome: violence, cluster: sports with parents). Active teens were less likely to have low self-esteem (eg, adolescents engaging in sports with parents, ARR: 0.73) and more likely to have higher grades (eg, active in school, ARR: 1.20). Participation in a range of PA-related behaviors, particularly those characterized by high parental sports/exercise involvement, was associated with favorable adolescent risk profiles. Adolescents with high TV/video viewership were less

  10. Physical Activity, Sedentary Behavior, and Dietary Patterns among Children

    NARCIS (Netherlands)

    Gubbels, J.S.; van Assema, P.; Kremers, S.P.

    2013-01-01

    Energy balance-related behavioral patterns find their origin in early The current paper provides an overview of studies that have examined behavioral patterns, i.e., the clustering of dietary behaviors, physical activity, and/or sedentary behavior. The paper discusses the importance examining energy

  11. [Associations of sedentary behavior and physical activity with dyslipidemia].

    Science.gov (United States)

    Zhou, J; Zhou, Q; Wang, D P; Zhang, T; Wang, H J; Song, Y; He, H Z; Wang, M; Wang, P Y; Liu, A P

    2017-06-18

    To analyze associations of sedentary behavior and physical activity with dyslipidemia among residents in Wuhai city. Data about social demographic characteristics, life style, health status and other covariate required for analysis in this study was obtained from a cross-sectional study on a total of 11 497 18-79 years old residents in Wuhai City by questionnaire, body mea-surement and laboratory examination. In this study, sedentary behavior and physical activity were evaluated using international physical activity questionnaire long version (IPAQ). IPAQ is widely used all over the world, and its reliability and validity have been tested in Chinese population. 2016 Chinese Guideline for the Management of Dyslipidemia in Adults was used to define dyslipidemia in this study. According to IPAQ scoring protocol, 124 participants were excluded as a result of reporting more than 960 min of physical activity per day. 50.58% of 11 373 participants included in the analysis reported more than 4 hours of sedentary behavior per day in this study, thus 49.42% participants reported no more than 4 hours of sedentary behavior per day; the proportions of these 11 373 participants who reached Low level physical activity, Moderate level physical activity and high level physical activity were 23.43%, 37.29% and 39.28% respectively; and the detection ratios of new cases and prevalent cases of dyslipidemia in Wuhai City were 20.46% and 16.13% respectively. After controlling for confounders in this study, we found out that sedentary behavior increased the risk of new cases of dyslipidemia in women (OR=1.17, 95% CI: 1.00-1.36), and increased the risk of prevalent cases of dyslipidemia in both men (OR=1.21, 95% CI: 1.02-1.44) and women (OR=1.24, 95% CI: 1.04-1.48); as for association of physical activity with dyslipidemia, association was found between high level physical activity and prevalent cases of dyslipidemia in men in this study (OR=0.78, 95% CI: 0.62-0.98), suggested that high

  12. Daily physical activity and screen time, but not other sedentary activities, are associated with measures of obesity during childhood.

    Science.gov (United States)

    Lee, Shoo Thien; Wong, Jyh Eiin; Shanita, Safii Nik; Ismail, Mohd Noor; Deurenberg, Paul; Poh, Bee Koon

    2014-12-23

    Childhood obesity is related to low physical activity level and a sedentary lifestyle. The aim of this study was to assess the physical activity level and sedentary behaviour of Malaysian children aged 7 to 12 years and to examine their association with body mass index (BMI), BMI-for-age Z-score (BAZ), body fatness (%BF) and waist circumference (WC). A total of 1736 children, representing all ethnic groups were recruited from six regions of Malaysia. Anthropometric measurements included body weight, height and waist circumference. Body fat percentage (%BF) was assessed using bioelectrical impedance. Physical activity was assessed by a physical activity questionnaire (PAQ) in all children and by pedometers in a subsample (n = 514). PAQ score and pedometer step counts were negatively associated with BMI, BAZ, %BF and WC after adjusting for covariates. Screen time was positively associated with BAZ and WC. However, other sedentary activities were not significantly related with any anthropometric indicators. Strategies to promote active living among children in Malaysia should focus not only on increasing physical activity but also emphasise reduction in sedentary behaviours.

  13. Daily Physical Activity and Screen Time, but Not Other Sedentary Activities, Are Associated with Measures of Obesity during Childhood

    Science.gov (United States)

    Lee, Shoo Thien; Wong, Jyh Eiin; Nik Shanita, Safii; Ismail, Mohd Noor; Deurenberg, Paul; Poh, Bee Koon

    2014-01-01

    Childhood obesity is related to low physical activity level and a sedentary lifestyle. The aim of this study was to assess the physical activity level and sedentary behaviour of Malaysian children aged 7 to 12 years and to examine their association with body mass index (BMI), BMI-for-age Z-score (BAZ), body fatness (%BF) and waist circumference (WC). A total of 1736 children, representing all ethnic groups were recruited from six regions of Malaysia. Anthropometric measurements included body weight, height and waist circumference. Body fat percentage (%BF) was assessed using bioelectrical impedance. Physical activity was assessed by a physical activity questionnaire (PAQ) in all children and by pedometers in a subsample (n = 514). PAQ score and pedometer step counts were negatively associated with BMI, BAZ, %BF and WC after adjusting for covariates. Screen time was positively associated with BAZ and WC. However, other sedentary activities were not significantly related with any anthropometric indicators. Strategies to promote active living among children in Malaysia should focus not only on increasing physical activity but also emphasise reduction in sedentary behaviours. PMID:25546277

  14. Daily Physical Activity and Screen Time, but Not Other Sedentary Activities, Are Associated with Measures of Obesity during Childhood

    Directory of Open Access Journals (Sweden)

    Shoo Thien Lee

    2014-12-01

    Full Text Available Childhood obesity is related to low physical activity level and a sedentary lifestyle. The aim of this study was to assess the physical activity level and sedentary behaviour of Malaysian children aged 7 to 12 years and to examine their association with body mass index (BMI, BMI-for-age Z-score (BAZ, body fatness (%BF and waist circumference (WC. A total of 1736 children, representing all ethnic groups were recruited from six regions of Malaysia. Anthropometric measurements included body weight, height and waist circumference. Body fat percentage (%BF was assessed using bioelectrical impedance. Physical activity was assessed by a physical activity questionnaire (PAQ in all children and by pedometers in a subsample (n = 514. PAQ score and pedometer step counts were negatively associated with BMI, BAZ, %BF and WC after adjusting for covariates. Screen time was positively associated with BAZ and WC. However, other sedentary activities were not significantly related with any anthropometric indicators. Strategies to promote active living among children in Malaysia should focus not only on increasing physical activity but also emphasise reduction in sedentary behaviours.

  15. Change in explicit and implicit motivation toward physical activity and sedentary behavior in pulmonary rehabilitation and associations with postrehabilitation behaviors.

    Science.gov (United States)

    Chevance, Guillaume; Héraud, Nelly; Varray, Alain; Boiché, Julie

    2017-05-01

    The aim of this study was twofold: (a) to determine whether Theory of Planned Behavior (TPB) variables and implicit attitudes toward physical activity and sedentary behavior would change during a 5-week pulmonary rehabilitation (PR) program, and (b) to investigate the relationships between behavioral intentions, implicit attitudes, physical activity, and sedentary behavior in postrehabilitation. Out of 142 patients with respiratory disease included in this study, 119 completed 2 questionnaires measuring TPB variables with regard to physical activity and sedentary behavior, and an Implicit Association Test (IAT) measuring implicit attitudes toward physical activity in contrast to sedentary behavior. The TPB questionnaires and the IAT were administered at the beginning (Time 1) and the end of the program (Time 2). Six months after the program (Time 3), 62 patients provided self-reported measures of their recreational physical activity and screen-based, leisure-time sedentary behavior. Over the course of pulmonary rehabilitation, perceived behavioral control and intentions toward physical activity increased, as did social norms and perceived behavioral control toward sedentary behavior; implicit attitudes were also more positive toward physical activity. Implicit attitudes at the end of PR (Time 2) were significantly associated with postrehabilitation physical activity (Time 3). TPB variables toward physical activity and sedentary behavior as well as implicit attitudes were enhanced during PR. At 6 months, implicit attitudes were significantly associated with physical activity. These results suggest that motivation, particularly implicit attitudes, should be targeted in future behavioral interventions in order to optimize the effects of rehabilitation on physical activity maintenance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  16. Accelerometer determined sedentary behavior and dietary quality among US adults.

    Science.gov (United States)

    Shuval, Kerem; Nguyen, Binh T; Yaroch, Amy L; Drope, Jeffrey; Gabriel, Kelley Pettee

    2015-09-01

    Scant evidence exists pertaining to objectively measured sedentary time and dietary quality among adults. Therefore, we examined the relationships between sedentary time, physical activity, and dietary quality. Cross-sectional analyses of a 4,910 US adults from two cycles (2003-2006) of the National Health and Nutrition Examination Survey. The primary independent variables were sedentary time and physical activity (continuous and categorical), while the outcomes were overall dietary quality (Healthy Eating Index (HEI) 2010), fruit and vegetable scores, and empty caloric intake (kcal). Multivariable analyses revealed that a 1min increase in daily sedentary behavior was associated with a 0.2kcal decrease in empty calories (-0.18, 95% CI=-0.34, -0.03); however, sedentary time was not significantly related to overall dietary quality (HEI) and fruit and vegetable intake. In comparison, a 1min increase in daily moderate-to-vigorous intensity physical activity was related to a 0.1 higher HEI score (0.08, 95% CI=0.04, 0.11), a 0.01 higher fruit score (0.01, 95% CI=0.01, 0.02), and conversely a 1.3kcal decrease in empty calories (-1.35, 95% CI=-2.01, -0.69). In addition, meeting physical activity guidelines was associated with a 2.8 point higher HEI score (2.82, 95% CI=1.40, 4.25), a 0.5 point higher fruit score (0.51, 95% CI=0.31-0.71), and 37.4 fewer empty calories (-37.43, 95% CI=-64.86, -9.10). Physical activity is significantly related to better overall dietary quality, while sedentary behavior is not. Findings suggest the need to promote physical activity and encourage adherence to dietary guidelines jointly, whereas sedentary behavior and overall dietary quality might need to be targeted independently. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Understanding the physical and social contexts of children's nonschool sedentary behavior: an ecological momentary assessment study.

    Science.gov (United States)

    Liao, Yue; Intille, Stephen; Wolch, Jennifer; Pentz, Mary Ann; Dunton, Genevieve Fridlund

    2014-03-01

    Research on children's sedentary behavior has relied on recall-based self-report or accelerometer methods, which do not assess the context of such behavior. This study used ecological momentary assessment (EMA) to determine where and with whom children's sedentary behavior occurs during their nonschool time. Children (N = 120) ages 9-13 years (51% male, 33% Hispanic) wore mobile phones that prompted surveys (20 total) for 4 days. Surveys measured current activity (eg, exercise, watching TV), physical location (eg, home, outdoors), and social company (eg, family, friends). Children engaged in a greater percentage of leisure-oriented (eg, watching TV) than productive (eg, reading, doing homework) sedentary behavior (70% vs 30%, respectively). Most of children's sedentary activity occurred at home (85%). Children's sedentary activity took place most often with family members (58%). Differences in physical context of sedentary behavior were found for older vs. younger children (P Research demonstrates the potential for using EMA to capture real-time information about children's sedentary behavior during their nonschool time.

  18. Why Do Children Engage in Sedentary Behavior? Child- and Parent-Perceived Determinants

    Directory of Open Access Journals (Sweden)

    Lisan M. Hidding

    2017-06-01

    Full Text Available Todays children spend a large amount of their time sedentary. There is limited evidence on the determinants of sedentary behavior in children, and qualitative studies are especially lacking. Therefore, this study aimed to explore determinants of children’s sedentary behavior from the child- and parent perspective. Qualitative data were collected during concept mapping sessions with four groups of 11–13 years old children (n = 38 and two online sessions with parents (n = 21. Children and parents generated sedentary behavior motives, sorted related motives, and rated their importance in influencing children’s sedentary time. Next, multidimensional scaling and hierarchical cluster analysis was performed to create clusters of motives resulting in a concept map. Finally, the researchers named the clusters in the concept map. Concept maps of children yielded eight to ten perceived determinants, and concept maps of parents six to seven. Children and parents identified six similar potential determinants, and both rated as important: Sitting because… “it is the norm (I have to”, and “I can work/play better that way”. In addition, children rated “there is nobody to play with” as an important potential determinant for engaging in sedentary behavior. The most important child- and parent perceived determinants were related to the social/cultural and physical environment, indicating that these are promising targets for future interventions.

  19. High blood pressure and sedentary behavior in adolescents are associated even after controlling for confounding factors.

    Science.gov (United States)

    Christofaro, Diego Giulliano Destro; De Andrade, Selma Maffei; Cardoso, Jefferson Rosa; Mesas, Arthur Eumann; Codogno, Jamile Sanches; Fernandes, Rômulo Araújo

    2015-01-01

    The aim of this study was to determine whether high blood pressure (HBP) is associated with sedentary behavior in young people even after controlling for potential confounders (gender, age, socioeconomic level, tobacco, alcohol, obesity and physical activity). In this epidemiological study, 1231 adolescents were evaluated. Blood pressure was measured with an oscillometric device and waist circumference with an inextensible tape. Sedentary behavior (watching television, computer use and playing video games) and physical activity were assessed by a questionnaire. We used mean and standard deviation to describe the statistical analysis, and the association between HBP and sedentary behavior was assessed by the chi-squared test. Binary logistic regression was used to observe the magnitude of association and cluster analyses (sedentary behavior and abdominal obesity; sedentary behavior and physical inactivity). HBP was associated with sedentary behaviors [odds ratio (OR) = 2.21, 95% confidence interval (CI) = 1.41-3.96], even after controlling for various confounders (OR = 1.68, CI = 1.03-2.75). In cluster analysis the combination of sedentary behavior and elevated abdominal obesity contributed significantly to an increased likelihood of having HBP (OR = 13.51, CI 7.21-23.97). Sedentary behavior was associated with HBP, and excess fat in the abdominal region contributed to the modulation of this association.

  20. Neighborhood environment correlates of physical activity and sedentary behavior among Latino adults in Massachusetts.

    Science.gov (United States)

    Silfee, Valerie J; Rosal, Milagros C; Sreedhara, Meera; Lora, Vilma; Lemon, Stephenie C

    2016-09-13

    U.S. Latinos experience high rates of cardio-metabolic diseases and have high rates of physical inactivity and sedentary behavior. Understanding the environmental factors associated with physical activity and sedentary behaviors among Latinos could inform future interventions. The purpose of this study is to explore the neighborhood environment correlates of physical activity and sedentary behavior in a sample of U.S. Latino adults. Cross-sectional study of 602 Latino adults in Lawrence, MA. Survey assessments of physical activity, sedentary behavior, and neighborhood environment were verbally administered. The neighborhood environment scale assessed violence, safety, aesthetic quality, walkability, availability of healthy foods, social cohesion, and activities with neighbors. After controlling forage, gender, education, body mass index (BMI), and smoking status, two variables were associated with the outcomes of interest. Living in more walkable neighborhoods was associated with an increased likelihood of engaging in adequate levels of physical activity (>150 min per week, as recommended by the American College of Sports Medicine (ACSM)) (OR = 1.403, p = .018); and greater frequency of activities with neighbors was associated with greater sedentary behavior (β = .072, p = .05). There were different neighborhood environment correlates of physical activity and sedentary behavior in this Latino community. Focusing on a greater understanding of the distinct social and physical environmental correlates of physical activity and sedentary behavior may provide important insights for reducing CVD risk and health disparities among Latinos.

  1. Neighborhood environment correlates of physical activity and sedentary behavior among Latino adults in Massachusetts

    Directory of Open Access Journals (Sweden)

    Valerie J. Silfee

    2016-09-01

    Full Text Available Abstract Background U.S. Latinos experience high rates of cardio-metabolic diseases and have high rates of physical inactivity and sedentary behavior. Understanding the environmental factors associated with physical activity and sedentary behaviors among Latinos could inform future interventions. The purpose of this study is to explore the neighborhood environment correlates of physical activity and sedentary behavior in a sample of U.S. Latino adults. Methods Cross-sectional study of 602 Latino adults in Lawrence, MA. Survey assessments of physical activity, sedentary behavior, and neighborhood environment were verbally administered. The neighborhood environment scale assessed violence, safety, aesthetic quality, walkability, availability of healthy foods, social cohesion, and activities with neighbors. Results After controlling forage, gender, education, body mass index (BMI, and smoking status, two variables were associated with the outcomes of interest. Living in more walkable neighborhoods was associated with an increased likelihood of engaging in adequate levels of physical activity (>150 min per week, as recommended by the American College of Sports Medicine (ACSM (OR = 1.403, p = .018; and greater frequency of activities with neighbors was associated with greater sedentary behavior (β = .072, p = .05. Conclusions There were different neighborhood environment correlates of physical activity and sedentary behavior in this Latino community. Focusing on a greater understanding of the distinct social and physical environmental correlates of physical activity and sedentary behavior may provide important insights for reducing CVD risk and health disparities among Latinos.

  2. Effect of Load on Friction-Wear Behavior of HVOF-Sprayed WC-12Co Coatings

    Science.gov (United States)

    Yifu, Jin; Weicheng, Kong; Tianyuan, Sheng; Ruihong, Zhang; Dejun, Kong

    2017-07-01

    A WC-12Co coating was sprayed on AISI H13 hot work mold steel using a high-velocity oxygen fuel. The morphologies, phase compositions, and distributions of chemical elements of the obtained coatings were analyzed using a field emission scanning electron microscope, x-ray diffraction, and energy-dispersive spectroscope (EDS), respectively. The friction-wear behaviors under different loads were investigated using a reciprocating wear tester; the morphologies and distributions of the chemical elements of worn tracks were analyzed using a SEM and its configured EDS, respectively. The results show the reunited grains of WC are held together by the Co binder; the primary phases of the coating are WC, Co, and a small amount of W2C and W, owing to the oxidation and decarburization of WC. Inter-diffusion of Fe and W between the coating and the substrate is shown, which indicates a good coating adhesion. The values of the average coefficient of friction under the loads of 40, 80, and 120 N are 0.29, 0.31, and 0.49, respectively. The WC grains are pulled out of the coating during the sliding wear test, but the coating maintains its integrity, suggesting that the coating is intact and continuously protects the substrate from wearing.

  3. School environment, sedentary behavior and physical activity in preschool children.

    Science.gov (United States)

    Barbosa, Sara Crosatti; Coledam, Diogo Henrique Constantino; Stabelini Neto, Antonio; Elias, Rui Gonçalves Marques; Oliveira, Arli Ramos de

    2016-09-01

    To analyze physical activity and sedentary behavior in preschool children during their stay at school and the associated factors. 370 preschoolers, aged 4 to 6 years, stratified according to gender, age and school region in the city of Londrina, PR, participated in the study. A questionnaire was applied to principals of preschools to analyze the school infrastructure and environment. Physical activity and sedentary behavior were estimated using accelerometers for five consecutive days during the children's stay at school. The odds ratio (OR) was estimated through binary logistic regression. At school, regardless of age, preschoolers spend relatively more time in sedentary behaviors (89.6%-90.9%), followed by light (4.6%-7.6%), moderate (1.3%-3.0%) and vigorous (0.5%-2.3%) physical activity. The indoor recreation room (OR=0.20; 95%CI 0.05 to 0.83) and the playground (OR=0.08; 95%CI 0.00 to 0.80) protect four-year-old schoolchildren from highly sedentary behavior. An inverse association was found between the indoor recreation room and physical activity (OR=0.20; 95%CI 0.00 to 0.93) in five-year-old children. The indoor recreation room (OR=1.54; 95%CI 1.35 to 1.77), the playground (OR=2.82; 95%CI 1.14 to 6.96) and the recess (OR=1.54; 95%CI 1.35 to 1.77) are factors that increase the chance of six-year-old schoolchildren to be active. The school infrastructure and environment should be seen as strategies to promote physical activity and reduce sedentary behavior in preschool children. Copyright © 2016 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

  4. Sedentary Behavior and Health: Broadening the Knowledge Base and Strengthening the Science

    Science.gov (United States)

    Hadgraft, Nyssa; Owen, Neville

    2017-01-01

    We provide an overview of a recently published, edited book in a rapidly emerging field of research, policy, and practice for physical activity: "Sedentary Behavior and Health". In this commentary, we highlight the broad perspectives provided in the 27 chapters of "Sedentary Behavior and Health" and suggest a research strategy…

  5. Towards a Personal Health Record System for the Assesment and Monitoring of Sedentary Behavior in Indoor Locations.

    Science.gov (United States)

    Ceron, Jesus D; Lopez, Diego M

    2016-01-01

    Sedentary behavior has been associated to the development of noncommunicable diseases (NCD) such as cardiovascular diseases (CVD), type 2 diabetes, and cancer. Accelerometers and inclinometers have been used to estimate sedentary behaviors, however a major limitation is that these devices do not provide contextual information such as the activity performed, e.g., TV viewing, sitting at work, driving, etc. The main objective of the thesis is to propose and evaluate a Personal Health Record System to support the assessment and monitoring of sedentary behaviors. Until now, we have implemented a system, which identifies individual's sedentary behaviors and location based on accelerometer data obtained from a smartwatch, and symbolic location data obtained from Bluetooth beacons. The system infers sedentary behaviors by means of a supervised Machine Learning Classifier. The precision in the classification of the six studied sedentary behaviors exceeded 90%, being the Random Forest algorithm the most precise. The proposed system allows the recognition of specific sedentary behaviors and their location with very high precision.

  6. Sedentary behavior and psychiatric symptoms in overweight and obese adults with schizophrenia and schizoaffective disorders (WAIST Study).

    Science.gov (United States)

    Janney, Carol A; Ganguli, Rohan; Richardson, Caroline R; Holleman, Rob G; Tang, Gong; Cauley, Jane A; Kriska, Andrea M

    2013-04-01

    Examine the association between sedentary behavior and psychiatric symptoms among overweight and obese adults with schizophrenia or schizoaffective disorders (SZO/SA). Randomized clinical trial; Weight Assessment and Intervention in Schizophrenia Treatment (WAIST) Study: baseline data collected 2005-2008. University of Pittsburgh Medical Center, Pittsburgh, PA, USA. Community-dwelling adults diagnosed with SZO/SA, with mild symptom severity [Positive and Negative Syndrome Scale (PANSS)losing weight, age 18-70years, BMI>27kg/m(2). Objectively measured sedentary behavior by accelerometry, and psychopathology assessed by PANSS. Participants wore the actigraphs for 7 consecutive days during their waking hours. Sedentary behavior was defined as ≤100 counts per minute during wear-time and excluded sleep and non-wear time. On average, 81% of the participant's monitoring time or 756min/day was classified as sedentary behavior using accelerometry. No association was observed between sedentary behaviors and PANSS psychiatric symptoms [total (p≥0.75), positive (p≥0.81), negative (p≥0.59) and general psychopathology (p≥0.65) subscales]. No association was observed between sedentary behaviors and age, race, gender and BMI. From a clinical and public health perspective, the amount of time (approximately 13h) and percentage of time (81% excluding non-wear time associated with sleeping) engaged in sedentary behavior among overweight and obese adults in this population is alarming, and points to an urgent need for interventions to decrease sedentary behaviors. The lack of associations between sedentary behavior and psychiatric symptoms may be due to a ceiling effect for sedentary behavior. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Physical activity, sustained sedentary behavior, and pain modulation in women with fibromyalgia.

    Science.gov (United States)

    Ellingson, Laura D; Shields, Morgan R; Stegner, Aaron J; Cook, Dane B

    2012-02-01

    Fibromyalgia (FM) has been conceptualized as a disorder of the central nervous system, characterized by augmented sensory processing and an inability to effectively modulate pain. We previously reported that physical activity is related to brain processing of pain, providing evidence for a potential mechanism of pain management. The purpose of this study was to extend our work by manipulating pain modulation and determining relationships to both physical activity and sustained sedentary behavior. Eleven women with FM completed accelerometer measures of physical activity and underwent functional magnetic resonance imaging of painful heat, administered alone and during distracting cognitive tasks. Results showed that physical activity was significantly (P sedentary time, significant negative relationships were observed in areas involved in both pain modulation and the sensory-discriminative aspects of pain including the DLPFC, thalamus, and superior frontal and pre- and post-central gyri. These results suggest that physical activity and sedentary behaviors are related to central nervous system regulation of pain in FM. Our results support a promising benefit of physical activity and highlight the potentially deleterious effects of sustained sedentary behavior for pain regulation in FM. Studies aimed at increasing physical activity or reducing sedentary behavior and determining the impact of these on pain regulation are warranted. Published by Elsevier Inc.

  8. Information Seeking in Social Media: A Review of YouTube for Sedentary Behavior Content.

    Science.gov (United States)

    Knight, Emily; Intzandt, Brittany; MacDougall, Alicia; Saunders, Travis J

    2015-01-20

    The global prevalence of sedentary lifestyles is of grave concern for public health around the world. Moreover, the health risk of sedentary behaviors is of growing interest for researchers, clinicians, and the general public as evidence demonstrates that prolonged amounts of sedentary time increases risk for lifestyle-related diseases. There is a growing trend in the literature that reports how social media can facilitate knowledge sharing and collaboration. Social sites like YouTube facilitate the sharing of media content between users. The purpose of this project was to identify sedentary behavior content on YouTube and describe features of this content that may impact the effectiveness of YouTube for knowledge translation. YouTube was searched on a single day by 3 independent reviewers for evidence-based sedentary behavior content. Subjective data (eg, video purpose, source, and activity type portrayed) and objective data (eg, number of views, comments, shares, and length of the video) were collected from video. In total, 106 videos met inclusion criteria. Videos were uploaded from 13 countries around the globe (ie, Australia, Barbados, Belgium, Canada, Colombia, Kenya, New Zealand, Russia, South Africa, Spain, Ukraine, United Kingdom, United States). The median video length was 3:00 minutes: interquartile range (IQR) 1:44-5:40. On average, videos had been on YouTube for 15.0 months (IQR 6.0-27.5) and had been viewed 239.0 times (IQR 44.5-917.5). Videos had remarkably low numbers of shares (median 0) and comments (median 1). Only 37.7% (40/106) of videos portrayed content on sedentary behaviors, while the remaining 66 videos portrayed physical activity or a mix of behaviors. Academic/health organizations (39.6%, 42/106) and individuals (38.7%, 41/106) were the most prevalent source of videos, and most videos (67.0%, 71/106) aimed to educate viewers about the topic. This study explored sedentary behavior content available on YouTube. Findings demonstrate that

  9. Correlates of urban children's leisure-time physical activity and sedentary behaviors during school days.

    Science.gov (United States)

    Marques, Adilson; Sallis, James F; Martins, João; Diniz, José; Carreiro Da Costa, Francisco

    2014-01-01

    Understanding correlates of physical activity and sedentary behaviors may contribute to fostering active lifestyles. This study aimed to identify correlates of physical activity and sedentary behaviors in leisure-time among Portuguese urban children, during school days. A cross-sectional survey was conducted with 802 students (416 boys), aged 10-12 years. A questionnaire was used to collect data of physical activity, sedentary behaviors, psychological and behavioral variables related to physical activity and sedentary behaviors. Analyses were run separately for boys and girls. Television viewing occupied the most leisure-time of boys and girls, followed by computer usage, and video game playing. These behaviors occupied 259.7 min/day for boys and 208.6 for girls (P = 0.002). Reported moderate-to-vigorous physical activity was 23.7 min for boys and 12.8 min for girls (P time with joint physical activity time. Copyright © 2014 Wiley Periodicals, Inc.

  10. Physical activity, sedentary behavior and their correlates in children with Autism Spectrum Disorder: A systematic review

    Science.gov (United States)

    Downing, Katherine; Rinehart, Nicole J.; Barnett, Lisa M.; May, Tamara; McGillivray, Jane A.; Papadopoulos, Nicole V.; Skouteris, Helen; Timperio, Anna

    2017-01-01

    Autism Spectrum Disorder affects up to 2.5% of children and is associated with harmful health outcomes (e.g. obesity). Low levels of physical activity and high levels of sedentary behaviors may contribute to harmful health outcomes. To systematically review the prevalence and correlates of physical activity and sedentary behaviors in children with Autism Spectrum Disorder, electronic databases (PsycINFO, SPORTDiscus, EMBASE, Medline) were searched from inception to November 2015. The review was registered with PROSPERO (CRD42014013849). Peer-reviewed, English language studies were included. Two reviewers screened potentially relevant articles. Outcomes of interest were physical activity and sedentary behaviour levels and their potential correlates. Data were collected and analysed in 2015. Of 35 included studies, 15 reported physical activity prevalence, 10 reported physical activity correlates, 18 reported sedentary behavior prevalence, and 10 reported sedentary behavior correlates. Estimates of children’s physical activity (34–166 mins/day, average 86 mins/day) and sedentary behavior (126–558 mins/day in screen time, average 271 mins/day; 428–750 mins/day in total sedentary behavior, average 479 mins/day) varied across studies. Age was consistently inversely associated, and sex inconsistently associated with physical activity. Age and sex were inconsistently associated with sedentary behavior. Sample sizes were small. All but one of the studies were classified as having high risk of bias. Few correlates have been reported in sufficient studies to provide overall estimates of associations. Potential correlates in the physical environment remain largely unexamined. This review highlights varying levels of physical activity and sedentary behavior in children with Autism Spectrum Disorder. Research is needed to consistently identify the correlates of these behaviors. There is a critical need for interventions to support healthy levels of these behaviors. PMID

  11. Weight Status in US Youth: The Role of Activity, Diet, and Sedentary Behaviors

    Science.gov (United States)

    Peart, Tasha; Velasco Mondragon, H. Eduardo; Rohm-Young, Deborah; Bronner, Yvonne; Hossain, Mian B.

    2011-01-01

    Objectives: To assess associations of physical activity, diet, and sedentary behaviors with overweight and obesity. Methods: Analyses of the NHANES 2003-06 were conducted among 2368 US adolescents, ages 12-19. Self-reported diet and sedentary behavior measures were used; physical activity was assessed using accelerometers. Results:…

  12. Momentary assessment of adults’ physical activity and sedentary behavior: Feasibility and validity

    Directory of Open Access Journals (Sweden)

    Genevieve Fridlund Dunton

    2012-07-01

    Full Text Available Introduction: Mobile phones are ubiquitous and easy to use, and thus have the capacity to collect real-time data from large numbers of people. Research tested the feasibility and validity of an Ecological Momentary Assessment (EMA self-report protocol using electronic surveys on mobile phones to assess adults’ physical activity and sedentary behaviors. Methods: Adults (N = 110 (73% female, 30% Hispanic, 62% overweight/obese completed a four-day signal-contingent EMA protocol (Sat. - Tues. with eight surveys randomly spaced throughout each day. EMA items assessed current activity (e.g., Watching TV/Movies, Reading/Computer, Physical Activity/Exercise. EMA responses were time-matched to minutes of moderate-to-vigorous physical activity (MVPA and sedentary activity (SA measured by accelerometer immediately before and after each EMA prompt. Results: Unanswered EMA prompts had greater MVPA (±15 min. than answered EMA prompts (p = .029 for under/normal weight participants, indicating that activity level might influence the likelihood of responding. The 15-min. intervals before vs. after the EMA-reported physical activity (n = 296 occasions did not differ in MVPA (p > .05, suggesting that prompting did not disrupt physical activity. SA decreased after EMA-reported sedentary behavior (n = 904 occasions (p < .05 for overweight and obese participants. As compared with other activities, EMA-reported physical activity and sedentary behavior had significantly greater MVPA and SA, respectively, in the ±15 minutes of the EMA prompt (p’s < .001, providing evidence for criterion validity. Conclusions: Findings generally support the acceptability and validity of a four-day signal contingent EMA protocol using mobile phones to measure physical activity and sedentary behavior in adults. However, some MVPA may be missed among underweight and normal weight individuals, and EMA may disrupt sedentary behavior among overweight/obese individuals.

  13. Genetics of regular exercise and sedentary behaviors.

    Science.gov (United States)

    de Geus, Eco J C; Bartels, Meike; Kaprio, Jaakko; Lightfoot, J Timothy; Thomis, Martine

    2014-08-01

    Studies on the determinants of physical activity have traditionally focused on social factors and environmental barriers, but recent research has shown the additional importance of biological factors, including genetic variation. Here we review the major tenets of this research to arrive at three major conclusions: First, individual differences in physical activity traits are significantly influenced by genetic factors, but genetic contribution varies strongly over age, with heritability of leisure time exercise behavior ranging from 27% to 84% and heritability of sedentary behaviors ranging from 9% to 48%. Second, candidate gene approaches based on animal or human QTLs or on biological relevance (e.g., dopaminergic or cannabinoid activity in the brain, or exercise performance influencing muscle physiology) have not yet yielded the necessary evidence to specify the genetic mechanisms underlying the heritability of physical activity traits. Third, there is significant genetic modulation of the beneficial effects of daily physical activity patterns on strength and endurance improvements and on health-related parameters like body mass index. Further increases in our understanding of the genetic determinants of sedentary and exercise behaviors as well as the genetic modulation of their effects on fitness and health will be key to meaningful future intervention on these behaviors.

  14. Patterns of sedentary behavior and compliance with public health recommendations in Spanish adolescents: the AFINOS study.

    Science.gov (United States)

    Martínez Gómez, David; Veiga, Oscar L; Zapatera, Belén; Cabanas-Sánchez, Verónica; Gomez-Martinez, Sonia; Martinez-Hernández, David; Marcos, Ascensión

    2012-12-01

    The aims of the present study were: (i) describe patterns of sedentary behavior in Spanish adolescents; and (ii) determine the proportion of adolescents that do not meet the public health recommendations for sedentary behavior. This study comprised 1,724 Spanish adolescents (882 girls), aged 13 to 16 years. Patterns of sedentary behavior (TV viewing, use of computer games, console games and surfing the Internet) were assessed using the HELENA sedentary behavior questionnaire. The total proportion of adolescents watching TV, using computer and console games, and surfing the internet for more than two hours daily was 24%, 9%, 7%, and 17%, respectively, on weekdays, and 50%, 22%, 16%, and 35%, respectively, on weekends. Over 63% of the adolescents from the study did not meet the recommendation for sedentary behavior (health, public health interventions in Spain that take these factors into consideration are needed.

  15. The effects of shift work on free-living physical activity and sedentary behavior.

    Science.gov (United States)

    Loprinzi, Paul D

    2015-07-01

    Although occupation may influence physical activity and shift work schedule may influence cardiovascular disease risk factors, our understanding of the effects of shift work schedule on overall physical activity behavior and sedentary behavior is limited. Data from the 2005-2006 National Health and Nutrition Examination Survey were used. Shift work schedule was defined as regular daytime shift, evening, night, rotating or another schedule. Physical activity and sedentary behavior were assessed via accelerometry. 1536 adult participants (≥20years) indicated they currently work and provided data on all study variables. After adjustments, and compared to adults working a regular daytime shift, those working an evening (RR=0.41, p=0.001) and night (RR=0.30, p=0.001) shift, respectively, engaged in 59% and 70% less sustained (bouts) moderate-to-vigorous physical activity, but no differences occurred for overall moderate-to-vigorous physical activity. After adjustments, and compared to those working a regular daytime shift, those working a rotating shift engaged in more light-intensity physical activity (overall: β=26.3min/day; p=0.03; bouts: β=37.5, p=0.01) and less sedentary behavior (β=-28.5min/day, p=0.01). Shift work schedule differentially influences physical activity and sedentary behavior. Physical activity and sedentary intervention strategies may need to be tailored based on shift work schedule. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Determinants of Sedentary Behavior, Motivation, Barriers and Strategies to Reduce Sitting Time in Older Women: A Qualitative Investigation

    Directory of Open Access Journals (Sweden)

    Sebastien F. M. Chastin

    2014-01-01

    Full Text Available Sedentary behavior defined as time spent non-exercising seated or reclining posture has been identified has a health risk and associated with frailty and disablement for older adults. Older adults are the most sedentary segment of society. To date no study has investigated the determinants of sedentary behavior in older adults. This study reports a qualitative investigation of the determinants of sedentary behavior, strategies and motivator to reduce sitting time by structured interviews in a group of community dwelling older women (N = 11, age 65 and over. Older women expressed the view that their sedentary behavior is mostly determined by pain which acts both as an incentive to sit and a motivator to stand up, lack of energy in the afternoon, pressure from direct social circle to sit and rest, societal and environmental typecasting that older adult are meant to sit, lack of environmental facilities to allow activity pacing. This qualitative investigation highlighted some factors that older adults consider determinants of their sedentary behavior. Some are identical to those affecting physical activity (self-efficacy, functional limitations, ageist stereotyping but some appear specific to sedentary behavior (locus of control, pain and should be further investigated and considered during intervention design. Tailored interventions that pay attention to the pattern of sedentary behavior of individuals appear to be supported by the views of older women on their sedentary behavior.

  17. The clustering of diet, physical activity and sedentary behavior in children and adolescents: a review.

    Science.gov (United States)

    Leech, Rebecca M; McNaughton, Sarah A; Timperio, Anna

    2014-01-22

    Diet, physical activity (PA) and sedentary behavior are important, yet modifiable, determinants of obesity. Recent research into the clustering of these behaviors suggests that children and adolescents have multiple obesogenic risk factors. This paper reviews studies using empirical, data-driven methodologies, such as cluster analysis (CA) and latent class analysis (LCA), to identify clustering patterns of diet, PA and sedentary behavior among children or adolescents and their associations with socio-demographic indicators, and overweight and obesity. A literature search of electronic databases was undertaken to identify studies which have used data-driven methodologies to investigate the clustering of diet, PA and sedentary behavior among children and adolescents aged 5-18 years old. Eighteen studies (62% of potential studies) were identified that met the inclusion criteria, of which eight examined the clustering of PA and sedentary behavior and eight examined diet, PA and sedentary behavior. Studies were mostly cross-sectional and conducted in older children and adolescents (≥ 9 years). Findings from the review suggest that obesogenic cluster patterns are complex with a mixed PA/sedentary behavior cluster observed most frequently, but healthy and unhealthy patterning of all three behaviors was also reported. Cluster membership was found to differ according to age, gender and socio-economic status (SES). The tendency for older children/adolescents, particularly females, to comprise clusters defined by low PA was the most robust finding. Findings to support an association between obesogenic cluster patterns and overweight and obesity were inconclusive, with longitudinal research in this area limited. Diet, PA and sedentary behavior cluster together in complex ways that are not well understood. Further research, particularly in younger children, is needed to understand how cluster membership differs according to socio-demographic profile. Longitudinal research is

  18. Interactions between tungsten carbide (WC) particulates and metal matrix in WC-reinforced composites

    International Nuclear Information System (INIS)

    Lou, D.; Hellman, J.; Luhulima, D.; Liimatainen, J.; Lindroos, V.K.

    2003-01-01

    A variety of experimental techniques have been used to investigate the interactions between tungsten carbide (WC-Co 88/12) particulates and the matrix in some new wear resistant cobalt-based superalloy and steel matrix composites produced by hot isostatic pressing. The results show that the chemical composition of the matrix has a strong influence on the interface reaction between WC and matrix and the structural stability of the WC particulates in the composite. Some characteristics of the interaction between matrix and reinforcement are explained by the calculation of diffusion kinetics. The three-body abrasion wear resistance of the composites has been examined based on the ASTM G65-91 standard procedure. The wear behavior of the best composites of this study shows great potential for wear protection applications

  19. Characterizing energy expenditure during sedentary behavior after stroke

    NARCIS (Netherlands)

    Verschuren, Olaf; de Haan, Femke; Mead, Gillian; Fengler, Ben; Visser-Meily, Anne

    2015-01-01

    OBJECTIVE: To objectively measure and calculate the energy expended by people with stroke during near sedentary behaviors (lying, supported and unsupported sitting, standing, wheelchair propulsion and walking), under controlled laboratory conditions, and compare these values to the energy

  20. Are sedentary television watching and computer use behaviors associated with anxiety and depressive disorders?

    NARCIS (Netherlands)

    de Wit, Leonore; van Straten, Annemieke; Lamers, Femke; Cuijpers, Pim; Penninx, Brenda

    2011-01-01

    Sedentary behaviors may be more common among persons with mental disorders and thereby result in poorer health outcomes. This study examined whether independently of general physical activity level, mental disorders are linked to two important examples of sedentary behavior: computer use and

  1. Screen and nonscreen sedentary behavior and sleep in adolescents.

    Science.gov (United States)

    Brunetti, Vanessa C; O'Loughlin, Erin K; O'Loughlin, Jennifer; Constantin, Evelyn; Pigeon, Étienne

    2016-12-01

    This study examined the associations between screen (computer, videogame, TV) and nonscreen (talking on the phone, doing homework, reading) sedentary time, and sleep in adolescents. Data were drawn from AdoQuest, a prospective investigation of 1843 grade 5 students aged 10-12 years at inception in the greater Montreal (Canada) area. Data for this cross-sectional analysis on screen and nonscreen sedentary time, sleep duration, and daytime sleepiness were collected in 2008-2009 from 1233 participants (67% of 1843) aged 14-16 years. Computer and videogame use >2 hours per day was associated with 17 and 11 fewer minutes of sleep per night, respectively. Computer use and talking on the phone were both associated with being a short sleeper (2 hours of computer use or talking on the phone per day had higher daytime sleepiness scores (11.9 and 13.9, respectively) than participants who reported d2 hours per day (9.7 and 10.3, respectively). Computer use and time spent talking on the phone are associated with short sleep and more daytime sleepiness in adolescents. Videogame time is also associated with less sleep. Clinicians, parents, and adolescents should be made aware that sedentary behavior and especially screen-related sedentary behavior may affect sleep duration negatively and is possibly associated with daytime sleepiness. Copyright \\© 2016 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  2. Physical activity and determinants of sedentary behavior in Brazilian adolescents from an underdeveloped region.

    Science.gov (United States)

    Guedes, Dartagnan P; Souza, Monica V; Ferreirinha, Jose E; Silva, Antonio Jose R M

    2012-04-01

    The purpose of the study was to analyze the physical activity and the determinants of sedentary behavior in 1,268 Brazilian adolescents (638 girls, 630 boys) between the ages of 15 and 18 years, randomly selected from a relatively underdeveloped region. Data were collected from a community-based survey in the city of João Pessoa, Paraiba, Brazil. Information related to physical activity was derived on the short version of the International Physical Activity Questionnaire. The prevalence of sedentary behavior was 28.2% for girls and 19.1% for boys, whilst 28.9% of the girls and 36.7% of the boys showed high physical activity. The sedentary behavior varied by sociodemographic and environmental determinants studied. Parents' education, socioeconomic status, school's characteristics, transport to school, paid work, smoking, alcohol use, and BMI scores were significantly related to sedentary behavior for boys and girls.

  3. Self-determined Engagement in Physical Activity and Sedentary Behaviors of US College Students

    OpenAIRE

    QUARTIROLI, ALESSANDRO; MAEDA, HOTAKA

    2014-01-01

    Although the importance of promoting physical activity is well established, researchers have recently considered ?sedentary behaviors? as another key risk factor for chronic disease. However, little is known about the motivational processes regulating sedentary behavior on a daily basis. A substantial amount of research has been based on the self-determination theory to examine the motivational processes regulating physical activity behaviors. However, only limited attention has been paid to ...

  4. The Role of Physical Activity and Sedentary Behavior in Substance Use and Risky Sex Behaviors in Hispanic Adolescents

    Science.gov (United States)

    Lebron, Cynthia; Stoutenberg, Mark; Janowsky, Mariel; Asfour, Lila; Huang, Shi; Prado, Guillermo

    2017-01-01

    The purpose of our study was to investigate the potential relationships in Hispanic adolescents (n = 575) between substance use and/or risky sexual behaviors and (a) physical activity (PA) and (b) sedentary time and (c) the moderating effect of gender. PA levels and sedentary behaviors were assessed using the PA Questionnaire for Adolescents,…

  5. Relationship between objectively measured sedentary behavior and health outcomes in schizophrenia patients: The PsychiActive project.

    Science.gov (United States)

    Bueno-Antequera, Javier; Oviedo-Caro, Miguel Ángel; Munguía-Izquierdo, Diego

    2017-11-21

    This study aimed to investigate possible relationships between sedentary behavior and body mass index (BMI), cardiorespiratory fitness (CRF), and health-related quality of life (HRQoL) in schizophrenia patients. Variables contributing to the variability in sedentary behavior were identified. Eighty-two schizophrenia outpatients (mean age±SD: 41.0±8.7years, 87% men, mean illness duration±SD: 17.1±8.9years) wore a multisensor armband for 7 consecutive full days to objectively measure sedentary behavior. BMI, walking capacity (6-minute walking test) as a proxy for CRF estimation and HRQoL (Short Form 36-Item Health Survey questionnaire version 2) were also assessed. Correlation (Pearson or Spearman coefficients) and multiple regression analysis were used. Sedentary behavior was significantly associated with BMI, CRF, and the physical component summary score of HRQoL (r values, -0.34-0.41; all Pdiet, smoking, and antipsychotic medication (all Psedentary behavior. Consistent relationships between sedentary behavior and BMI, CRF, and the physical component summary score of HRQoL were found in schizophrenia patients. All the identified determinants of sedentary behavior are modifiable and may be important areas for future interventions in this population. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Association of Active Play-Related Parenting Behaviors, Orientations, and Practices with Preschool Sedentary Behavior

    Science.gov (United States)

    Loprinzi, Paul D.; Cardinal, Bradley J.; Kane, Christy; Lee, Hyo; Beets, Michael W.

    2014-01-01

    Background: Parents' behaviors, practices, beliefs, and attitudes greatly influence children's active play behavior; however, little research has examined these parental influences on preschool children's sedentary behavior (SB). Purpose: The purpose of this study was to examine the association between parental influences on preschool SB. Methods:…

  7. Time spent in physical activity and sedentary behaviors on the working day: the American time use survey.

    Science.gov (United States)

    Tudor-Locke, Catrine; Leonardi, Claudia; Johnson, William D; Katzmarzyk, Peter T

    2011-12-01

    To determine time spent on the working day in sleep, work, sedentary behaviors, and light-, moderate-, and vigorous-intensity behaviors by occupation intensity. Data came from 30,758 working respondents to the 2003 to 2009 American Time Use Survey. Mean ± SEM time spent in work, sedentary behaviors, light-, moderate-, and vigorous-intensity activities, and sleep were computed by occupations classified as sedentary, light, moderate, and vigorous intensity. On average, approximately 32% of the 24-hour day was spent sleeping and approximately 31% was spent at work. Time spent in sedentary behaviors outside of work was higher, and light-intensity time was lower, with higher levels of intensity-defined occupation. Those employed in sedentary occupations were sedentary for approximately 11 hours per day, leaving little time to achieve recommended levels of physical activity for overall health.

  8. Sedentary behaviors, physical activity behaviors, and body fat in 6-year-old children: the generation R study.

    Science.gov (United States)

    Wijtzes, Anne I; Bouthoorn, Selma H; Jansen, Wilma; Franco, Oscar H; Hofman, Albert; Jaddoe, Vincent Wv; Raat, Hein

    2014-08-15

    Childhood overweight and obesity is a major public health concern. Knowledge on modifiable risk factors is needed to design effective intervention programs. This study aimed to assess associations of children's sedentary behaviors (television viewing and computer game use) and physical activity behaviors (sports participation, outdoor play, and active transport to/from school) with three indicators of body fat, i.e., percent fat mass, body mass index (BMI) standard deviation scores, and weight status (normal weight, overweight). Cross-sectional data from 5913 6-year-old ethnically diverse children were analyzed. Children's weight and height were objectively measured and converted to BMI. Weight status was defined according to age- and sex-specific cut-off points of the International Obesity Task Force. BMI standard deviation scores were created, based on Dutch reference growth curves. Fat mass was measured my dual-energy X-ray absorptiometry (DXA). Sedentary and physical activity behaviors were assessed by parent-reported questionnaires. Series of logistic and linear regression analyses were performed, controlling for confounders (i.e., socio-demographic factors, family lifestyle factors, and other sedentary behaviors and physical activity behaviors). Sports participation was inversely associated with fat mass (p sedentary behaviors and physical activity behaviors. No other independent associations were observed. The results of this study indicate that sports participation is inversely associated with percent body fat among ethnically diverse 6-year-old children. More research in varied populations including objective measurements and longitudinal designs are needed to confirm these current results.

  9. Physical Activity, Sedentary Behavior, and Dietary Patterns among Children

    OpenAIRE

    Gubbels, Jessica S.; van Assema, Patricia; Kremers, Stef P. J.

    2013-01-01

    Energy balance-related behavioral patterns find their origin in early childhood. The current paper provides an overview of studies that have examined such behavioral patterns, i.e., the clustering of dietary behaviors, physical activity, and/or sedentary behavior. The paper discusses the importance of examining energy balance-related behavioral patterns in children, outlines methods to examine these patterns, and provides examples of patterns that have been found (e.g., the universal sedentar...

  10. Empowering Sedentary Adults to Reduce Sedentary Behavior and Increase Physical Activity Levels and Energy Expenditure: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Faisal A. Barwais

    2015-01-01

    Full Text Available Objective: The purpose of this study was to assess the effectiveness of a 4-week intervention in which an online personal activity monitor (Gruve-Technologies™ was used to reduce sedentary behavior among sedentary adults. Method: Eighteen, sedentary adult volunteers (12 men, six women, mean age 29 ± 4.0 years were recruited to participate in the study. Time spent in sedentary activities and light-, moderate-, and vigorous-intensity physical activity and energy expenditure were assessed during waking hours using the monitor and the 7-day SLIPA Log at both baseline and post-intervention. Results: A significant decrease of 33% (3.1 h/day; p < 0.001 was found between the time spent in sedentary activities measured at baseline (9.4 ± 1.1 h/day and at the end of the 4-week intervention (6.3 ± 0.8 h/day. Consequent to the changes in sedentary time, significant increases were found in the amount of time spent in light- (45% (2.6 h/day, p < 0.001, moderate- (33% (1 h/day p < 0.001, vigorous-intensity physical activity (39% (0.16 h/day, p < 0.001, and energy expenditure (47% (216.7 kcal/day, p < 0.001. Conclusion: This monitor contributes to a meaningful reduction in time spent in sedentary activities and has a large effect on energy expenditure and physical activity patterns.

  11. Perceived neighborhood safety related to physical activity but not recreational screen-based sedentary behavior in adolescents.

    Science.gov (United States)

    Lenhart, Clare M; Wiemken, Andrew; Hanlon, Alexandra; Perkett, Mackenzie; Patterson, Freda

    2017-09-18

    A growing proportion of adolescents have poor cardiovascular health behaviors, including low levels of physical activity and high levels of sedentary behavior, thus increasing the likelihood of poor heart health in later years. This study tested the hypothesis that low perceived neighborhood safety would be associated with low levels of physical activity and high levels of recreational sedentary behavior in high-school students. Using cross-sectional, weighted data from the 2015 Pennsylvania (USA) State and Philadelphia city Youth Risk Behavior Survey, multivariable logistic regression modeling was used to examine the association between perceived neighborhood safety, and physical activity levels and recreational screen-based sedentary behavior time respectively, while controlling for potential confounders. After adjustment for other significant correlates of physical activity, students with low perceived neighborhood safety had a 21% reduced odds of being physically active on 5 or more days of the last week as compared to those who felt safe (p = 0.044). Perceived safety was not related to sedentary behavior; but sports team participation emerged as a strong correlate of low screen-based sedentary behavior (OR = 0.73, p = .002). These data add to a growing body of work demonstrating the importance of perceived safety with physical activity levels in youth. Sports team participation may be a viable target to reduce screen-based sedentary time.

  12. Perceived neighborhood safety related to physical activity but not recreational screen-based sedentary behavior in adolescents

    Directory of Open Access Journals (Sweden)

    Clare M. Lenhart

    2017-09-01

    Full Text Available Abstract Background A growing proportion of adolescents have poor cardiovascular health behaviors, including low levels of physical activity and high levels of sedentary behavior, thus increasing the likelihood of poor heart health in later years. This study tested the hypothesis that low perceived neighborhood safety would be associated with low levels of physical activity and high levels of recreational sedentary behavior in high-school students. Methods Using cross-sectional, weighted data from the 2015 Pennsylvania (USA State and Philadelphia city Youth Risk Behavior Survey, multivariable logistic regression modeling was used to examine the association between perceived neighborhood safety, and physical activity levels and recreational screen-based sedentary behavior time respectively, while controlling for potential confounders. Results After adjustment for other significant correlates of physical activity, students with low perceived neighborhood safety had a 21% reduced odds of being physically active on 5 or more days of the last week as compared to those who felt safe (p = 0.044. Perceived safety was not related to sedentary behavior; but sports team participation emerged as a strong correlate of low screen-based sedentary behavior (OR = 0.73, p = .002. Conclusion These data add to a growing body of work demonstrating the importance of perceived safety with physical activity levels in youth. Sports team participation may be a viable target to reduce screen-based sedentary time.

  13. Objectively measured sedentary behavior, physical activity, and plasma lipids in overweight and obese children.

    Science.gov (United States)

    Cliff, Dylan P; Okely, Anthony D; Burrows, Tracy L; Jones, Rachel A; Morgan, Philip J; Collins, Clare E; Baur, Louise A

    2013-02-01

    This study examines the associations between objectively measured sedentary behavior, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA), and plasma lipids in overweight and obese children. Cross-sectional analyses were conducted among 126 children aged 5.5-9.9 years. Sedentary behavior, LPA, and MVPA were assessed using accelerometry. Fasting blood samples were analyzed for plasma lipids (high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol [LDL-C], total cholesterol [TC], and triglycerides [TG]). MVPA was not related to plasma lipids (P > 0.05). Independent of age, sex, energy intake, and waist circumference z-score, sedentary behavior and LPA were associated with HDL-C (β = -0.23, 95% CI -0.42 to -0.04, P = 0.020; β = 0.20, 95% CI 0.14 to 0.39, P = 0.036, respectively). The strength of the associations remained after additionally adjusting for MVPA (sedentary behavior: β = -0.22, 95% CI -0.44 to 0.006, P = 0.056; LPA: β = 0.19, 95% CI -0.005 to 0.38, P = 0.056, respectively). Substituting at least LPA for sedentary time may contribute to the development of healthy HDL-C levels among overweight and obese children, independent of their adiposity. Comprehensive prevention and treatment strategies to improve plasma HDL-C among overweight and obese children should target reductions in total sedentary time and promote the benefits of LPA, in addition to promoting healthy levels of adiposity, healthy dietary behaviors, and MVPA. Copyright © 2012 The Obesity Society.

  14. Adolescents' Sedentary Behaviors in Two European Cities

    Science.gov (United States)

    Aibar Solana, Alberto; Bois, Julien E.; Zaragoza, Javier; Bru, Noëlle; Paillard, Thierry; Generelo, Eduardo

    2015-01-01

    Purpose: The aim of this study was to determine and compare the correlates of objective sedentary behavior (SB) and nonschool self-reported SB in adolescents from 2 midsized cities, 1 in France (Tarbes) and 1 in Spain (Huesca). Stability of objective SB and nonschool self-reported SB were also assessed at different time points during 1 academic…

  15. The clustering of diet, physical activity and sedentary behavior in children and adolescents: a review

    Science.gov (United States)

    2014-01-01

    Diet, physical activity (PA) and sedentary behavior are important, yet modifiable, determinants of obesity. Recent research into the clustering of these behaviors suggests that children and adolescents have multiple obesogenic risk factors. This paper reviews studies using empirical, data-driven methodologies, such as cluster analysis (CA) and latent class analysis (LCA), to identify clustering patterns of diet, PA and sedentary behavior among children or adolescents and their associations with socio-demographic indicators, and overweight and obesity. A literature search of electronic databases was undertaken to identify studies which have used data-driven methodologies to investigate the clustering of diet, PA and sedentary behavior among children and adolescents aged 5–18 years old. Eighteen studies (62% of potential studies) were identified that met the inclusion criteria, of which eight examined the clustering of PA and sedentary behavior and eight examined diet, PA and sedentary behavior. Studies were mostly cross-sectional and conducted in older children and adolescents (≥9 years). Findings from the review suggest that obesogenic cluster patterns are complex with a mixed PA/sedentary behavior cluster observed most frequently, but healthy and unhealthy patterning of all three behaviors was also reported. Cluster membership was found to differ according to age, gender and socio-economic status (SES). The tendency for older children/adolescents, particularly females, to comprise clusters defined by low PA was the most robust finding. Findings to support an association between obesogenic cluster patterns and overweight and obesity were inconclusive, with longitudinal research in this area limited. Diet, PA and sedentary behavior cluster together in complex ways that are not well understood. Further research, particularly in younger children, is needed to understand how cluster membership differs according to socio-demographic profile. Longitudinal research

  16. Determinants of Sedentary Behavior, Motivation, Barriers and Strategies to Reduce Sitting Time in Older Women: A Qualitative Investigation

    OpenAIRE

    Chastin, Sebastien F. M.; Fitzpatrick, Nicole; Andrews, Michelle; DiCroce, Natalie

    2014-01-01

    Sedentary behavior defined as time spent non-exercising seated or reclining posture has been identified has a health risk and associated with frailty and disablement for older adults. Older adults are the most sedentary segment of society. To date no study has investigated the determinants of sedentary behavior in older adults. This study reports a qualitative investigation of the determinants of sedentary behavior, strategies and motivator to reduce sitting time by structured interviews in ...

  17. Objectively Quantified Physical Activity and Sedentary Behavior in Predicting Visceral Adiposity and Liver Fat

    Directory of Open Access Journals (Sweden)

    Shelley E. Keating

    2016-01-01

    Full Text Available Objective. Epidemiologic studies suggest an inverse relationship between nonalcoholic fatty liver disease (NAFLD, visceral adipose tissue (VAT, and self-reported physical activity levels. However, subjective measurements can be inaccurate and prone to reporter bias. We investigated whether objectively quantified physical activity levels predicted liver fat and VAT in overweight/obese adults. Methods. Habitual physical activity was measured by triaxial accelerometry for four days (n=82. Time spent in sedentary behavior (MET < 1.6 and light (MET 1.6 < 3, moderate (MET 3 < 6, and vigorous (MET 6 < 9 physical activity was quantified. Magnetic resonance imaging and spectroscopy were used to quantify visceral and liver fat. Bivariate correlations and hierarchical multiple regression analyses were performed. Results. There were no associations between physical activity or sedentary behavior and liver lipid. Sedentary behavior and moderate and vigorous physical activity accounted for just 3% of variance for VAT (p=0.14 and 0.003% for liver fat (p=0.96. Higher levels of VAT were associated with time spent in moderate activity (r=0.294, p=0.007, but there was no association with sedentary behavior. Known risk factors for obesity-related NAFLD accounted for 62% and 40% of variance in VAT and liver fat, respectively (p<0.01. Conclusion. Objectively measured levels of habitual physical activity and sedentary behavior did not influence VAT or liver fat.

  18. Associations between physical inactivity and sedentary behaviors among adolescents in 10 cities in China.

    Science.gov (United States)

    Chen, You; Zheng, Zhonghui; Yi, Jinyao; Yao, Shuqiao

    2014-07-22

    Studies in western countries have revealed that excessive sedentary behavior is a major risk factor for physical inactivity in adolescents. This study was performed to investigate the association between sedentary behavior and physical inactivity in Chinese adolescents using a large-scale cross-sectional survey design. This study was part of the 2011 Chinese Youth Risk Behavior Survey. Between March and September 2011, 10,214 11-18-year-olds were recruited for survey participation in 18 schools in 10 cities in China. Demographic and socioeconomic characteristics, and the prevalences of physical inactivity and sedentary behaviors, were examined. Correlations between sedentary behavior and physical inactivity were analyzed using baseline logistic regression. Among the final 9,901 students, physical inactivity (~80%) and sedentary behaviors (television viewing, 43%; computer use, 30.2%) were prevalent. More male than female students reported sedentary behaviors (television viewing > 2 h: 5.5% vs. 3.9%; computer use > 2 h: 7.2% vs. 3.5%; both p physically active than females (25.1% vs.14.6%; p physical activity (No PA) in males [0-2 h: adjusted odds ratio (AOR) = 0.81, 95% confidence interval (CI) = 0.68-0.96; >4 h: OR = 0.34, 95% CI = 0.18-0.64], but not in females. A similar pattern between insufficient physical activity and >4 h TV viewing (AOR = 0.42, 95% CI = 0.23-0.76) and >4 h computer use (AOR = 0.49, 95% CI = 0.30-0.78) was observed in males. In females, 0-2 h daily computer use was associated with higher odds of physical inactivity (No PA: AOR = 1.42, 95% CI = 1.10-1.82; Insufficient PA: AOR = 1.58, 95% CI = 1.24-2.01), while TV viewing was not associated with No PA or Insufficient PA. The probability of physical inactivity significantly increased with grade and decreased with socioeconomic status. Physical inactivity and sedentary behaviors were prevalent in Chinese adolescents. Further support, including parental guidance and the provision of

  19. [Leisure-time physical activity and sedentary behaviors among Chinese adults in 2010].

    Science.gov (United States)

    Chen, Xiao-rong; Jiang, Yong; Wang, Li-min; Li, Yi-chong; Zhang, Mei; Hu, Nan; Zhao, Wen-hua

    2012-05-01

    To understand the prevalence of participation in leisure-time physical activity, and sedentary behaviors among Chinese adults. Data from Chinese Chronic Disease Surveillance (2010) was used. Among adults aged 18 years old and over, the information on frequency and duration of occupational activity, house chores, commuting and leisure time activity was collected by an interview with Global Physical Activity Questionnaire (GPAQ). The time spent on watching TV, reading, using computers or playing games after work was also surveyed. This present study only analyzed the percentage of participating in leisure time moderate or vigorous intensity physical activity at least 10 minutes three days per week and the time spent on TV, reading, using computer and playing games during after hours among Chinese adults of 98 649 subjects. 11.9% (95%CI: 10.5% - 13.3%) of all adults took part in leisure time moderate or vigorous intensity physical activity at least 10 minutes for three days per week, with-group the percentage highest among age-group 18 - 24 (15.6%, 95%CI: 10.5% - 13.3%) and lowest among age 25 - 34 (9.9%, 95%CI: 8.0% - 11.7%) and 75 years old and over (9.9%, 95%CI: 8.2% - 11.6%) (P sedentary behaviors, such as watching TV, reading, using computers or playing games during after hours. Those aged 18 - 24 years-old spent most time (3.8 ± 2.6) hours per day in sedentary behaviors and the time reduced with age (P Sedentary behaviors were taken by male (2.9 ± 2.1 hours per day) than by female ((2.6 ± 1.9) hours per day) (P 0.05). The percentage of taking part in moderate and vigorous activity during leisure time was generally low. Average time spent in after hours sedentary behaviors was long.

  20. Sedentary behavior during school-time: Sociodemographic, weight status, physical education class, and school performance correlates in Brazilian schoolchildren.

    Science.gov (United States)

    da Costa, Bruno G G; da Silva, Kelly S; George, Amanda M; de Assis, Maria Alice A

    2017-01-01

    To investigate whether sedentary behavior during school-time is associated with gender, age, mother's education, having physical education classes, weight status, and academic performance. Cross-sectional study. A sample of 571 children (7-12 years old) from five elementary schools in Florianopolis, South Brazil had their height and weight measured, and wore accelerometers during class time. Teachers completed a form to evaluate children's reading and writing skills. Parents provided sociodemographic and educational information. Data was analyzed using multilevel linear regression analyses. Children spent an average of 132min in sedentary behavior during school-time (64% of total school-time). Girls (137.5min), obese children (138.1min), older children (144.2min), and those who did not have physical education classes (140.2min) spent more time engaged in sedentary activities than their peers. Academic performance and mother's education were not associated with sedentary behaviors. Children spent most of their school-time in sedentary activities, with girls, older students, and obese students being even more sedentary than their peers. Physical education classes were a protective factor against excessive sedentary behavior in school. Interventions for reducing sedentary behavior during school-time could employ additional strategies to benefit the at risk groups. In addition, encouraging student's participation in physical education classes could minimize the time spent in sedentary behavior during school hours. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  1. Microstructure, Wear Behavior and Corrosion Resistance of WC-FeCrAl and WC-WB-Co Coatings

    Directory of Open Access Journals (Sweden)

    Janette Brezinová

    2018-05-01

    Full Text Available The paper is focused on investigating the quality of two grades of thermally sprayed coatings deposited by high-velocity oxygen fuel (HVOF technology. One grade contains WC hard particles in an environmentally progressive Ni- and Co-free FeCrAl matrix, while the second coating contains WC and WB hard particles in a cobalt matrix. The aim of the experimental work was to determine the effect of thermal cyclic loading on the coatings’ resistance to adhesive, abrasive and erosive wear. Abrasive wear was evaluated using abrasive cloth of two grit sizes, and erosive wear was evaluated by a dry-pot wear test in a pin mill at two sample angles. Adhesion wear resistance of the coatings was determined by a sliding wear test under dry friction conditions and in a 1 mol water solution of NaCl. Corrosion resistance of the coatings was evaluated using potentiodynamic polarization tests. Metallographic cross-sections were used for measurement of the microhardness and thickness and for line energy-dispersive X-ray (EDX analysis. The tests proved the excellent resistance of both coatings against adhesive, abrasive, and erosive wear, as well as the ability of the WC-WB-Co coating to withstand alternating temperatures of up to 600 °C. The “green carbide” coating (WC-FeCrAl can be recommended as an environmentally friendly replacement for Ni- and Co-containing coatings, but its operating temperature is strictly limited to 500 °C in air.

  2. Physical activity, energy intake, sedentary behavior, and adiposity in youth.

    Science.gov (United States)

    Fulton, Janet E; Dai, Shifan; Steffen, Lyn M; Grunbaum, Jo Anne; Shah, Syed M; Labarthe, Darwin R

    2009-07-01

    It is unclear to what extent factors affecting energy balance contribute to the development of body fatness in youth. The objective of the current study was to describe the relationship of physical activity, energy intake, and sedentary behavior to BMI, fat free-mass index (FFMI), and fat mass index (FMI) in children aged 10-18 years. In the subsample studied, participants were 245 girls and 227 boys (aged > or =10 years at entry or during follow-up assessments, or aged 11-14 years at entry) followed for 4 years from entry at ages 8, 11, or 14 years. At baseline and anniversary examinations, trained interviewers used a questionnaire to assess time spent daily in moderate-to-vigorous physical activity (MVPA), sedentary behavior, and energy intake (kcal/day). Sexual maturation was assessed by direct observation of pubic-hair development (Tanner Stages 1-5). Triplicate recordings of height and weight were used to estimate BMI by the standard formula (kg/m(2)); bioelectric impedance was used to estimate percent body fat for calculating FFMI and FMI (kg/m(2)). Multilevel models were used to examine the association of MVPA, energy intake, and sedentary behavior with BMI, FFMI, and FMI. Data were analyzed in 2007-2008. Energy intake was unrelated to FMI or FFMI in models adjusted for age or sexual maturation or in any model to BMI. Sedentary behavior was unrelated to FMI in any model or to FFMI or BMI in models adjusted for age or sexual maturation. MVPA was inversely related to FMI. In children aged 10-18 years, MVPA was inversely associated with fat mass and with BMI. Investigations in youth of dietary intake and physical activity, including interventions to prevent or reverse overweight as represented by BMI, should address its fat and lean components and not BMI alone.

  3. Mechanical Properties and Wear Behavior of AA5182/WC Nanocomposite Fabricated by Friction Stir Welding at Different Tool Traverse Speeds

    Science.gov (United States)

    Paidar, Moslem; Asgari, Ali; Ojo, Olatunji Oladimeji; Saberi, Abbas

    2018-03-01

    Grain growth inhibition at the heat-affected zone, improved weld strength and superior tribological properties of welds are desirable attributes of modern manufacturing. With the focused on these attributes, tungsten carbide (WC) nanoparticles were employed as reinforcements for the friction stir welding of 5-mm-thick AA5182 aluminum alloy by varying tool traverse speeds. The microstructure, microhardness, ultimate tensile strength, fracture and wear behavior of the resultant WC-reinforced welds were investigated, while unreinforced AA5182 welds were employed as controls for the study. The result shows that the addition of WC nanoparticles causes substantial grain refinement within the weld nugget. A decrease in traverse speed caused additional particle fragmentation, improved hardness value and enhanced weld strength in the reinforced welds. Improved wear rate and friction coefficient of welds were attained at a reduced traverse speed of 100 mm/min in the WC-reinforced welds. This improvement is attributed to the effects of reduced grain size/grain fragmentation and homogeneous dispersion of WC nanoparticles within the WC-reinforced weld nugget.

  4. Friendship Network Characteristics Are Associated with Physical Activity and Sedentary Behavior in Early Adolescence.

    Science.gov (United States)

    Marks, Jennifer; de la Haye, Kayla; Barnett, Lisa M; Allender, Steven

    2015-01-01

    There is limited understanding of the association between peer social networks and physical activity (PA), sedentary and screen-related behaviors. This study reports on associations between personal network characteristics and these important health behaviors for early adolescents. Participants were 310 students, aged 11-13 years, from fifteen randomly selected Victorian primary schools (43% response rate). PA and sedentary behaviors were collected via accelerometer and self-report questionnaire, and anthropometric measures via trained researchers. Participants nominated up to fifteen friends, and described the frequency of interaction and perceived activity intensity of these friends. Personal network predictors were examined using regression modelling for PA and sedentary/screen behavior. Perceived activity levels of friends, and friendships with very frequent interaction were associated with outside-of-school PA and/or sedentary/screen time. Differences according to sex were also observed in the association between network characteristics and PA and sedentary time. A higher number of friends and greater proportion of same sex friends were associated with boys engaging in more moderate-to-vigorous PA outside of school hours. PA intensity during school-day breaks was positively associated with having a greater proportion of friends who played sports for girls, and a greater proportion of male friends for boys. Friendship network characteristics are associated with PA and sedentary/screen time in late childhood/early adolescence, and these associations differ by sex. The positive influence of very active peers may be a promising avenue to strengthen traditional interventions for the promotion of PA and reduction in screen time.

  5. Sedentary behavior, physical activity and cardiorespiratory fitness on leukocyte telomere length.

    Science.gov (United States)

    Edwards, Meghan K; Loprinzi, Paul D

    2017-01-01

    Background: Emerging work is starting to investigate the cumulative effects of moderate-to-vigorous physical activity (MVPA), sedentary behavior and cardiorespiratory fitness on health. The objective of this study was to examine the cumulative and independent associations of MVPA, sedentary behavior and cardiorespiratory fitness on leukocyte telomere length (LTL). Methods: Data from the 1999-2002 National Health and Nutrition Examination Survey (NHANES) were used (N = 1868 adults 20+ years); analyzed in 2016. Sedentary behavior and MVPA were subjectively assessed with cardiorespiratory fitness determined from a submaximal treadmill-based test; participants were classified as above or below the median values for each of these three parameters. A blood sample was obtained from each participant to assess LTL via quantitative polymerase chain reaction, with participants grouped into LTL tertiles. Results: Participants who engaged in higher MVPA, sat less and had higher cardiorespiratory fitness had an increased odds (ranging from 85% to 105%) of being in LTL tertile 3 (vs. 1). In an extended adjusted multinomial logistic regression model, only MVPA was positively associated with LTL (odds ration [OR] = 1.37; 95% CI: 0.99-1.90; P = 0.05). Conclusion: All three behavior characteristics, but particularly MVPA, may be important in preserving LTLs.

  6. Which Type of Sedentary Behavior Intervention is More Effective at Reducing Body Mass Index in Children? A Meta-Analytic Review

    OpenAIRE

    Liao, Yue; Liao, Jingjing; Durand, Casey P.; Dunton, Genevieve F

    2013-01-01

    Sedentary behavior is emerging as an independent risk factor for pediatric obesity. Some evidence suggests that limiting sedentary behavior alone could be effective in reducing body mass index (BMI) in children. However, whether adding physical activity and diet-focused components to sedentary behavior reduction interventions could lead to an additive effect is unclear. This meta-analysis aims to assess the overall effect size of sedentary behavior interventions on BMI reduction, and to compa...

  7. Cross-Sectional Relationships of Physical Activity and Sedentary Behavior With Cognitive Function in Older Adults With Probable Mild Cognitive Impairment.

    Science.gov (United States)

    Falck, Ryan S; Landry, Glenn J; Best, John R; Davis, Jennifer C; Chiu, Bryan K; Liu-Ambrose, Teresa

    2017-10-01

    Mild cognitive impairment (MCI) represents a transition between normal cognitive aging and dementia and may represent a critical time frame for promoting cognitive health through behavioral strategies. Current evidence suggests that physical activity (PA) and sedentary behavior are important for cognition. However, it is unclear whether there are differences in PA and sedentary behavior between people with probable MCI and people without MCI or whether the relationships of PA and sedentary behavior with cognitive function differ by MCI status. The aims of this study were to examine differences in PA and sedentary behavior between people with probable MCI and people without MCI and whether associations of PA and sedentary behavior with cognitive function differed by MCI status. This was a cross-sectional study. Physical activity and sedentary behavior in adults dwelling in the community (N = 151; at least 55 years old) were measured using a wrist-worn actigraphy unit. The Montreal Cognitive Assessment was used to categorize participants with probable MCI (scores of Cognitive function was indexed using the Alzheimer Disease Assessment Scale-Cognitive-Plus (ADAS-Cog Plus). Physical activity and sedentary behavior were compared based on probable MCI status, and relationships of ADAS-Cog Plus with PA and sedentary behavior were examined by probable MCI status. Participants with probable MCI (n = 82) had lower PA and higher sedentary behavior than participants without MCI (n = 69). Higher PA and lower sedentary behavior were associated with better ADAS-Cog Plus performance in participants without MCI (β = -.022 and β = .012, respectively) but not in participants with probable MCI (β cognitive function. The diagnosis of MCI was not confirmed with a physician; therefore, this study could not conclude how many of the participants categorized as having probable MCI would actually have been diagnosed with MCI by a physician. Participants with probable MCI were less active

  8. Investigating Elementary School Children's Daily Physical Activity and Sedentary Behaviors during Weekdays

    Science.gov (United States)

    Gao, Zan; Chen, Senlin; Huang, Chaoqun; Stodden, David F.; Xiang, Ping

    2017-01-01

    Purpose The purpose of the study was to quantify the contributions of physical education, exergaming (active video games that also are a type of exercise), recess, lunch break and after-school time segments to children's daily physical activity and sedentary behaviors. Methods Participants were 138 second and third graders (71 girls) who attended 20-minute recess and 75-minute lunch time daily, 25-minute regular physical education or exergaming-based classes being alternated daily. The after-school period was defined as 3:20-10:00pm. Physical activity was assessed via accelerometry and the dependent variables were children's time spent in moderate-to-vigorous physical activity (MVPA), light physical activity, and sedentary behavior. Results Children's percentages of time spent in MVPA (p < .001; except for the difference between exergaming and lunch break: p = .63), light physical activity (p < .001), and sedentary behavior (p < .001) differed significantly across the time segments (i.e., physical education/exergaming, recess, lunch break, and after-school). Additionally, children accumulated significantly more MVPA (t = 10.22, p < .001) but less light physical activity (t = -3.17, p = .002) and sedentary behavior (t = -3.91, p < .001) in physical education than in exergaming. Conclusions Overall, physical education was more effective in generating MVPA than other segments over the school day. The after-school segment holds potential as an avenue for promoting children's MVPA, as this long period could be better utilized to organize structured physical activity. PMID:26950823

  9. Sampling and analysis of inactive radioactive waste tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14 at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Sears, M.B.; Giaquinto, J.M.; Griest, W.H.; Pack, R.T.; Ross, T.; Schenley, R.L.

    1995-12-01

    The sampling and analysis of nine inactive liquid low-level waste (LLLW) tanks at the Oak Ridge National Laboratory (ORNL) are described-tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14. Samples of the waste tank liquids and sludges were analyzed to determine (1) the major chemical constituents, (2) the principal radionuclides, (3) metals listed on the US Environmental Protection Agency (EPA) Contract Laboratory Program Inorganic Target Analyte List, (4) organic compounds, and (5) some physical properties. The organic chemical characterization consisted of determinations of the EPA Contract Laboratory Program Target Compound List volatile and semivolatile compounds, pesticides, and polychlorinated biphenyis (PCBs). This report provides data (1) to meet requirements under the Federal Facility Agreement (FFA) for the Oak Ridge Reservation to characterize the contents of LLLW tanks which have been removed from service and (2) to support planning for the treatment and disposal of the wastes.

  10. Sampling and analysis of inactive radioactive waste tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14 at ORNL

    International Nuclear Information System (INIS)

    Sears, M.B.; Giaquinto, J.M.; Griest, W.H.; Pack, R.T.; Ross, T.; Schenley, R.L.

    1995-12-01

    The sampling and analysis of nine inactive liquid low-level waste (LLLW) tanks at the Oak Ridge National Laboratory (ORNL) are described-tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14. Samples of the waste tank liquids and sludges were analyzed to determine (1) the major chemical constituents, (2) the principal radionuclides, (3) metals listed on the US Environmental Protection Agency (EPA) Contract Laboratory Program Inorganic Target Analyte List, (4) organic compounds, and (5) some physical properties. The organic chemical characterization consisted of determinations of the EPA Contract Laboratory Program Target Compound List volatile and semivolatile compounds, pesticides, and polychlorinated biphenyis (PCBs). This report provides data (1) to meet requirements under the Federal Facility Agreement (FFA) for the Oak Ridge Reservation to characterize the contents of LLLW tanks which have been removed from service and (2) to support planning for the treatment and disposal of the wastes

  11. Objectively measured sedentary behavior and physical activity in office employees: relationships with presenteeism.

    Science.gov (United States)

    Brown, Helen Elizabeth; Ryde, Gemma C; Gilson, Nicholas D; Burton, Nicola W; Brown, Wendy J

    2013-08-01

    Employee presenteeism is the extent to which health conditions adversely affect at-work productivity. Given the links between health and activity, this study examined associations between objectively measured physical activity, sedentary behavior, and presenteeism. Participants were 108 office employees (70% women, mean age 40.7 ± 11.2 years). Activity was measured using ActiGraph GT3X+ accelerometers to determine sedentary (≤150 counts) and light (151 to 1689 counts) activity; presenteeism with the Work Limitations Questionnaire. Fifty-seven percent of time was spent in sedentary behavior and 38% in light activity. The median Work Limitations Questionnaire Index was 4.38; 6% of participants reported at least moderate impairment. Significant associations were reported for time spent in sedentary behavior before/after work (odds ratio [OR] = 2.58; 95% CI: 1.08 to 6.20) and in light activity, overall (OR = 0.43; 95% CI: 0.19 to 0.97) and during workday lunch hours (OR = 0.34; 95% CI: 0.15 to 0.77), and presenteeism. Future studies should seek greater variation in employee levels of activity and presenteeism to confirm these relationships.

  12. Physical activity and sedentary behavior of cancer survivors and non-cancer individuals: results from a national survey.

    Science.gov (United States)

    Kim, Roy B; Phillips, Allison; Herrick, Kirsten; Helou, Marieka; Rafie, Carlin; Anscher, Mitchell S; Mikkelsen, Ross B; Ning, Yi

    2013-01-01

    Increasing physical activity and decreasing sedentary behavior are associated with a higher quality of life and lower mortality rates for cancer survivors, a growing population group. Studies detailing the behavior of cancer survivors are limited. Therefore, we investigated physical activity and sedentary behavior of cancer survivors using data from the National Health and Nutrition Examination Survey (NHANES) 2007-2010. Participants were those who provided physical activity and sedentary behavior data. Those who were pregnant, physical activity, compared to non-cancer participants. These patterns are similar for breast and prostate cancer survivors, with prostate cancer survivors more likely to engage in physical activity for more than one hour per day (OR = 1.98, 95% CI (1.05, 3.71)). Our findings suggest that cancer survivors tend to have more physical activity, but they are also more likely to engage in sedentary behavior.

  13. Advances in population surveillance for physical activity and sedentary behavior: reliability and validity of time use surveys.

    Science.gov (United States)

    van der Ploeg, Hidde P; Merom, Dafna; Chau, Josephine Y; Bittman, Michael; Trost, Stewart G; Bauman, Adrian E

    2010-11-15

    Many countries conduct regular national time use surveys, some of which date back as far as the 1960s. Time use surveys potentially provide more detailed and accurate national estimates of the prevalence of sedentary and physical activity behavior than more traditional self-report surveillance systems. In this study, the authors determined the reliability and validity of time use surveys for assessing sedentary and physical activity behavior. In 2006 and 2007, participants (n = 134) were recruited from work sites in the Australian state of New South Wales. Participants completed a 2-day time use diary twice, 7 days apart, and wore an accelerometer. The 2 diaries were compared for test-retest reliability, and comparison with the accelerometer determined concurrent validity. Participants with similar activity patterns during the 2 diary periods showed reliability intraclass correlations of 0.74 and 0.73 for nonoccupational sedentary behavior and moderate/vigorous physical activity, respectively. Comparison of the diary with the accelerometer showed Spearman correlations of 0.57-0.59 and 0.45-0.69 for nonoccupational sedentary behavior and moderate/vigorous physical activity, respectively. Time use surveys appear to be more valid for population surveillance of nonoccupational sedentary behavior and health-enhancing physical activity than more traditional surveillance systems. National time use surveys could be used to retrospectively study nonoccupational sedentary and physical activity behavior over the past 5 decades.

  14. A pilot study of physical activity and sedentary behavior distribution patterns in older women.

    Science.gov (United States)

    Fortune, Emma; Mundell, Benjamin; Amin, Shreyasee; Kaufman, Kenton

    2017-09-01

    The study aims were to investigate free-living physical activity and sedentary behavior distribution patterns in a group of older women, and assess the cross-sectional associations with body mass index (BMI). Eleven older women (mean (SD) age: 77 (9) yrs) wore custom-built activity monitors, each containing a tri-axial accelerometer (±16g, 100Hz), on the waist and ankle for lab-based walking trials and 4 days in free-living. Daily active time, step counts, cadence, and sedentary break number were estimated from acceleration data. The sedentary bout length distribution and sedentary time accumulation pattern, using the Gini index, were investigated. Associations of the parameters' total daily values and coefficients of variation (CVs) of their hourly values with BMI were assessed using linear regression. The algorithm demonstrated median sensitivity, positive predictive value, and agreement values >98% and <1% mean error in cadence calculations with video identification during lab trials. Participants' sedentary bouts were found to be power law distributed with 56% of their sedentary time occurring in 20min bouts or longer. Meaningful associations were detectable in the relationships of total active time, step count, sedentary break number and their CVs with BMI. Active time and step counts had moderate negative associations with BMI while sedentary break number had a strong negative association. Active time, step count and sedentary break number CVs also had strong positive associations with BMI. The results highlight the importance of measuring sedentary behavior and suggest a more even distribution of physical activity throughout the day is associated with lower BMI. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Physical activity, sedentary behavior, and vitamin D metabolites.

    Science.gov (United States)

    Hibler, Elizabeth A; Sardo Molmenti, Christine L; Dai, Qi; Kohler, Lindsay N; Warren Anderson, Shaneda; Jurutka, Peter W; Jacobs, Elizabeth T

    2016-02-01

    Physical activity is associated with circulating 25-hydroxyvitamin D (25(OH)D). However, the influence of activity and/or sedentary behavior on the biologically active, seco-steroid hormone 1α,25-dihydroxyvitamin D (1,25(OH)2D) is unknown. We conducted a cross-sectional analysis among ursodeoxycholic acid (UDCA) randomized trial participants (n=876) to evaluate associations between physical activity, sedentary behavior, and circulating vitamin D metabolite concentrations. Continuous vitamin D metabolite measurements and clinical thresholds were evaluated using multiple linear and logistic regression models, mutually adjusted for either 1,25(OH)2D or 25(OH)D and additional confounding factors. A statistically significant linear association between 1,25(OH)2D and moderate-vigorous physical activity per week was strongest among women (β (95% CI): 3.10 (1.51-6.35)) versus men (β (95% CI): 1.35 (0.79-2.29)) in the highest tertile of activity compared to the lowest (p-interaction=0.003). Furthermore, 25(OH)D was 1.54ng/ml (95% CI 1.09-1.98) higher per hour increase in moderate-vigorous activity (p=0.001) and odds of sufficient 25(OH)D status was higher among physically active participants (p=0.001). Sedentary behavior was not significantly associated with either metabolite in linear regression models, nor was a statistically significant interaction by sex identified. The current study identified novel associations between physical activity and serum 1,25(OH)2D levels, adjusted for 25(OH)D concentrations. These results identify the biologically active form of vitamin D as a potential physiologic mechanism related to observed population-level associations between moderate-vigorous physical activity with bone health and chronic disease risk. However, future longitudinal studies are needed to further evaluate the role of physical activity and vitamin D metabolites in chronic disease prevention. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Objectively-determined intensity- and domain-specific physical activity and sedentary behavior in relation to percent body fat.

    Science.gov (United States)

    Scheers, Tineke; Philippaerts, Renaat; Lefevre, Johan

    2013-12-01

    This study examined the independent and joint associations of overall, intensity-specific and domain-specific physical activity and sedentary behavior with bioelectrical impedance-determined percent body fat. Physical activity was measured in 442 Flemish adults (41.4 ± 9.8 years) using the SenseWear Armband and an electronic diary. Two-way analyses of covariance investigated the interaction of physical activity and sedentary behavior with percent body fat. Multiple linear regression analyses, adjusted for potential confounders, examined the associations of intensity-specific and domain-specific physical activity and sedentary behavior with percent body fat. Results showed a significant main effect for physical activity in both genders and for sedentary behavior in women, but no interaction effects. Light activity was positively (β = 0.41 for men and 0.43 for women) and moderate (β = -0.64 and -0.41), vigorous (β = -0.21 and -0.24) and moderate-to-vigorous physical activity (MVPA) inversely associated with percent body fat, independent of sedentary time. Regarding domain-specific physical activity, significant associations were present for occupation, leisure time and household chores, irrespective of sedentary time. The positive associations between body fat and total and domain-specific sedentary behavior diminished after MVPA was controlled for. MVPA during leisure time, occupation and household chores may be essential to prevent fat gain. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  17. The clustering of diet, physical activity and sedentary behavior in children and adolescents: a review

    OpenAIRE

    Leech, Rebecca M; McNaughton, Sarah A; Timperio, Anna

    2014-01-01

    Diet, physical activity (PA) and sedentary behavior are important, yet modifiable, determinants of obesity. Recent research into the clustering of these behaviors suggests that children and adolescents have multiple obesogenic risk factors. This paper reviews studies using empirical, data-driven methodologies, such as cluster analysis (CA) and latent class analysis (LCA), to identify clustering patterns of diet, PA and sedentary behavior among children or adolescents and their associations wi...

  18. Cognitive and Motivational Factors Associated with Sedentary Behavior: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Scott Rollo

    2016-11-01

    Full Text Available Excessive time spent in sedentary behavior (SB is associated with numerous health risks. These associations remain even after controlling for moderate-to-vigorous physical activity (PA and body mass index, indicating that efforts to promote leisure time physical activity alone are insufficient. Cognitive and motivation variables represent potentially modifiable factors and have the potential of furthering our understanding of sedentary behavior. Hence, a systematic review was conducted to synthesize and critique the literature on the relationship between cognitive and motivational factors and sedentary behaviors. In April 2016, four electronic databases (Psych info, Pub Med, SPORTDiscus, Web of Science were searched and a total of 4866 titles and abstracts were reviewed. After meeting inclusion criteria, study characteristics were extracted and the methodological quality of each study was assessed according to the Downs and Black Checklist. PRISMA guidelines for reporting of systematic reviews were followed. Twenty-five studies (16 cross-sectional, 8 longitudinal and one examining two populations and employing both a cross-sectional and prospective design assessed 23 different cognitive and motivational factors. Seventeen studies were theory-based and 8 did not employ a theoretical model. Results showed that among SB-related cognitions, risk factors for greater sedentary time included having a more positive attitude towards SB, perceiving greater social support/norms for SB, reporting greater SB habits, having greater intentions to be sedentary, and having higher intrinsic, introjected, and external motivation towards SB. Protective factors associated with lower sedentary time included having greater feelings of self-efficacy/control over SB and greater intentions to reduce SB. Among PA-related cognitions, protective factors for lower SB included a more positive attitude towards PA, having greater social support/norms for PA, greater self

  19. Joint associations of objectively-measured sedentary behavior and physical activity with health-related quality of life.

    Science.gov (United States)

    Loprinzi, Paul D

    2015-01-01

    No studies, to my knowledge, have examined the joint effects of physical activity and sedentary behavior on health-related quality of life (HRQOL), which was the purpose of this study. Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used (N = 5,536). Moderate-to-vigorous physical activity (MVPA) and sedentary behavior were assessed using an ActiGraph 7164 accelerometer, with HRQOL assessed using the Centers for Disease Control and Prevention 4-item HRQOL index. MVPA (βadjusted = - 0.01; 95% CI: - 0.01 to - 0.004; P sedentary behavior (βadjusted = - 0.0003; 95% CI: - 0.001-0.0001; P = 0.37), was associated with HRQOL. MVPA was associated with HRQOL among those above the median (≥ 487.5 min/day) level of sedentary behavior (βadjusted = - 0.02; 95% CI: - 0.03 to - 0.01; P = 0.006; N = 2769). The results of this brief report do not demonstrate that sedentary behavior, independent of MVPA, is associated with HRQOL. The independent association of MVPA on HRQOL confirms previous work that used self-report measures of MVPA.

  20. Joint associations of objectively-measured sedentary behavior and physical activity with health-related quality of life

    Directory of Open Access Journals (Sweden)

    Paul D. Loprinzi

    2015-01-01

    Full Text Available No studies, to my knowledge, have examined the joint effects of physical activity and sedentary behavior on health-related quality of life (HRQOL, which was the purpose of this study. Data from the 2003–2006 National Health and Nutrition Examination Survey (NHANES were used (N = 5,536. Moderate-to-vigorous physical activity (MVPA and sedentary behavior were assessed using an ActiGraph 7164 accelerometer, with HRQOL assessed using the Centers for Disease Control and Prevention 4-item HRQOL index. MVPA (βadjusted = −0.01; 95% CI: −0.01 to −0.004; P < 0.001, but not sedentary behavior (βadjusted = −0.0003; 95% CI: −0.001–0.0001; P = 0.37, was associated with HRQOL. MVPA was associated with HRQOL among those above the median (≥487.5 min/day level of sedentary behavior (βadjusted = −0.02; 95% CI: −0.03 to −0.01; P = 0.006; N = 2769. The results of this brief report do not demonstrate that sedentary behavior, independent of MVPA, is associated with HRQOL. The independent association of MVPA on HRQOL confirms previous work that used self-report measures of MVPA.

  1. The Physical Activity Levels and Sedentary Behaviors of Latino Children in London (Ontario, Canada

    Directory of Open Access Journals (Sweden)

    Gillian Mandich

    2015-05-01

    Full Text Available Objective: To assess the physical activity and sedentary behaviors of a sample of Latino children in London, Ontario, Canada. Methods: Seventy-four Latino children (54.1% male; mean age = 11.4 completed self-report questionnaires related to physical activity and sedentary behaviors. A subset of children (n = 64 wore Actical (Mini Mitter, Respironics accelerometers for a maximum of four days. Results: Latino children self-reported moderate levels of physical activity (i.e., mean score of 2.8 on 5-point scale. Accelerometer data revealed that children spent an average of 50.0 min in moderate-to-vigorous physical activity (MVPA; 59.2 min on weekdays and 50.6 min on weekend days and were sedentary for an average of 8.4 h (508.0 min per day (533.5 min on weekdays and 497.7 min on weekend days. Children reported spending an average of 3.8 h (228 min daily in front of screens—1.7 h (102 min watching television, 1.2 h (72 min on the computer, and 0.9 h (54 min playing video games. Conclusions: This feasibility project provided a preliminary account of objectively measured daily physical activity and sedentary time among a sample of Latino children in Canada, as well as insight into the challenge of measuring these behaviors. Sedentary behavior reduction techniques should be explored and implemented in this young population, along with strategies to promote adherence to accelerometer protocols.

  2. 24 Hours of Sleep, Sedentary Behavior, and Physical Activity with Nine Wearable Devices

    OpenAIRE

    Rosenberger, Mary E.; Buman, Matthew P.; Haskell, William L.; McConnell, Michael V.; Carstensen, Laura L.

    2016-01-01

    Getting enough sleep, exercising and limiting sedentary activities can greatly contribute to disease prevention and overall health and longevity. Measuring the full 24-hour activity cycle - sleep, sedentary behavior (SED), light intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) - may now be feasible using small wearable devices.

  3. Context-Specific Associations of Physical Activity and Sedentary Behavior With Cognition in Children.

    Science.gov (United States)

    Aggio, Daniel; Smith, Lee; Fisher, Abigail; Hamer, Mark

    2016-06-15

    In the present study, we investigated how overall and specific domains of physical activity and sedentary behavior at the age of 7 years were associated with cognition at the age of 11 years in 8,462 children from the Millennium Cohort Study. Data were collected from 2001 to 2013. Participation in domains of physical activity and sedentary behavior at 7 years of age were reported. Activity levels were also measured objectively. Cognition was assessed using the British Ability Scales. General linear models were used to assess longitudinal associations of physical activity and sedentary behavior, measured both objectively and via self-report, with cognition. Analyses were adjusted for prespecified covariates. Sports/physical activity club attendance (B = 0.6, 95% confidence interval (CI): 0.2, 1.1), doing homework (B = 0.5, 95% CI: 0.0, 0.9), and objectively measured sedentary time (B = 0.8, 95% CI: 0.1, 1.4) at age 7 years were positively associated with cognition at age 11 years in final the models. Television viewing was negatively associated with cognition (B = -1.7, 95% CI: -2.4, -1.0), although the association was attenuated to the null after adjustments for baseline cognition. Objectively measured light physical activity was inversely associated with cognition (B = -0.7, 95% CI: -1.3, -0.1). Moderate-to-vigorous physical activity was also inversely associated with cognition in girls only (B = -1.1, 95% CI: -2.0, -0.3). Associations of physical activity and sedentary behavior with cognition appear to be context-specific in young people. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

  4. Decreasing sedentary behavior by 30 minutes per day reduces cardiovascular disease risk factors in rural Americans.

    Science.gov (United States)

    Saleh, Zyad T; Lennie, Terry A; Mudd-Martin, Gia; Bailey, Alison L; Novak, Michael J; Biddle, Martha; Khalil, Amani A; Darawad, Muhammad; Moser, Debra K

    2015-01-01

    Regular physical activity has been associated with reduced cardiovascular disease (CVD) risk factors; however, a decrease in the amount of time spent during the remainder of the day in sedentary behavior may be equally important. The aim of this study was to examine the effects of a decrease in sedentary behavior on CVD risk factors among 205 individuals living in rural Appalachia. All participants received a comprehensive CVD risk reduction life-style intervention and measurement of major CVD risk factors and physical activity levels. Participants were divided into: 1) Adopters: those who decreased their sedentary behavior by 30 min or more per day post-intervention and 2) Non-adopters: those who did not. Repeated measures analysis of variance showed a significant group by time interaction showing that Adopters had a greater reduction in body weight and BMI than Non-adopters. These findings demonstrate that decreasing sedentary behavior is important for achieving optimal body weight. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Adult self-reported and objectively monitored physical activity and sedentary behavior: NHANES 2005–2006

    Science.gov (United States)

    2013-01-01

    Background It remains unclear what people are attempting to communicate, in terms of objectively monitored behavior, when describing their physical activity and sedentary behavior through self-report. The purpose of this study was to examine various objectively monitored accelerometer variables (e.g., moderate-to-vigorous physical activity [MVPA], steps/day, sedentary time, etc.) across categories of self-reported MVPA (activity (UODA; “mostly sitting” vs. “stand, walk, lift, or carry”), and leisure-time sedentary behavior (LTSB; ≥ 3 vs. behavior between categories of self-reported MVPA, UODA, and LTSB. Results On average, adults reporting compliance with physical activity guidelines (≥ 150 minutes/week of MVPA) accumulated more objectively measured physical activity and similar amounts of sedentary time relative to those reporting not achieving guidelines. Adults reporting their daily UODA as “mostly sitting” or accruing ≥ 3 hours/day of LTSB accumulated less objectively monitored physical activity and more sedentary time than those who described their UODA as “stand, walk, lift, or carry” or accrued active cross-classified category (7,935 steps/day; ≥ 150 minutes/week of self-reported MVPA, “stand, walk, lift, or carry” UODA, and active cross-classified category (3,532 steps/day; physical activity indicators varied significantly between self-reported MVPA, UODA, and LTSB categories, while objectively monitored sedentary time only varied between UODA and LTSB categories. Cross-classifications of self-reported MVPA, UODA, and LTSB responses depict a greater range of physical activity than viewing dichotomous responses for these variables one-at-a-time. PMID:24215625

  6. A prospective investigation of neighborhood socioeconomic deprivation and physical activity and sedentary behavior in older adults.

    Science.gov (United States)

    Xiao, Qian; Keadle, Sarah K; Berrigan, David; Matthews, Charles E

    2018-06-01

    Neighborhood conditions may have an important impact on physical activity and sedentary behaviors in the older population. Most previous studies in this area are cross-sectional and report mixed findings regarding the effects of neighborhood environment on different types of physical activity. Moreover, little is known about the prospective relationship between neighborhood environment and sedentary behaviors. Our analysis included 136,526 participants from the NIH-AARP Diet and Health Study (age 51-70). Neighborhood socioeconomic deprivation was measured with an index based on census variables and developed using principal component analysis. Physical activity and sedentary behaviors were measured both at baseline (1995-1996) and follow-up (2004-2006). Multiple regression analyses were conducted to examine the prospective relationship between neighborhood deprivation and exercise, non-exercise physical activity, and sedentary behaviors, adjusting for baseline physical activity and sedentary behaviors as well as potential confounders. We found that more severe neighborhood socioeconomic deprivation was prospectively associated with reduced time for exercise (β Q5 vs Q1 (95% confidence interval), hour, -0.85 (-0.95, -0.75)) but increased time spent in non-exercise physical activities (1.16 (0.97, 1.34)), such as household activities, outdoor chores, and walking for transportation. Moreover, people from more deprived neighborhoods were also more likely to engage in prolonged (≥5 h/day) TV viewing (Odds ratio Q5 vs Q1 (95% confidence interval), 1.21 (1.15, 1.27)). In conclusion, neighborhood socioeconomic deprivation is associated with physical activity and sedentary behavior in the older population. These associations may differ for different types of physical activities. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Schoolyard Characteristics, Physical Activity, and Sedentary Behavior: Combining GPS and Accelerometry

    Science.gov (United States)

    Van Kann, Dave H. H.; de Vries, Sanne I.; Schipperijn, Jasper; de Vries, Nanne K.; Jansen, Maria W. J.; Kremers, Stef P. J.

    2016-01-01

    Background: Physical activity (PA) is decreasing among children, while sedentary behavior (SB) is increasing. Schoolyards seem suitable settings to influence children's PA behavior. This study investigated the associations between schoolyard characteristics and moderate-to-vigorous physical activity (MVPA) and SB of children aged 8-11 years at…

  8. Behavioral and Psychological Phenotyping of Physical Activity and Sedentary Behavior: Implications for Weight Management.

    Science.gov (United States)

    Bryan, Angela D; Jakicic, John M; Hunter, Christine M; Evans, Mary E; Yanovski, Susan Z; Epstein, Leonard H

    2017-10-01

    Risk for obesity is determined by a complex mix of genetics and lifetime exposures at multiple levels, from the metabolic milieu to psychosocial and environmental influences. These phenotypic differences underlie the variability in risk for obesity and response to weight management interventions, including differences in physical activity and sedentary behavior. As part of a broader effort focused on behavioral and psychological phenotyping in obesity research, the National Institutes of Health convened a multidisciplinary workshop to explore the state of the science in behavioral and psychological phenotyping in humans to explain individual differences in physical activity, both as a risk factor for obesity development and in response to activity-enhancing interventions. Understanding the behavioral and psychological phenotypes that contribute to differences in physical activity and sedentary behavior could allow for improved treatment matching and inform new targets for tailored, innovative, and effective weight management interventions. This summary provides the rationale for identifying psychological and behavioral phenotypes relevant to physical activity and identifies opportunities for future research to better understand, define, measure, and validate putative phenotypic factors and characterize emerging phenotypes that are empirically associated with initiation of physical activity, response to intervention, and sustained changes in physical activity. © 2017 The Obesity Society.

  9. Towards a Persuasive Mobile Application to Reduce Sedentary Behavior

    NARCIS (Netherlands)

    Van Dantzig, S.; Geleijnse, G.; Van Halteren, A.T.

    2011-01-01

    Prolonged sitting is a potential health risk, not only for people with an inactive lifestyle, but also for those who do meet the recommended amount of physical activity. In this paper, we present two waysto promote the reduction of sedentary behavior. First, we report onan experiment in which office

  10. Comparative study of the friction and wear behavior of plasma sprayed conventional and nanostructured WC-12%Co coatings on stainless steel

    International Nuclear Information System (INIS)

    Zhao Xiaoqin; Zhou Huidi; Chen Jianmin

    2006-01-01

    Conventional and nanostructured WC-12%Co coatings were deposited on 1Cr18Ni9Ti stainless steel substrate using air plasma spraying. The hardness of the coatings was measured, while their friction and wear behavior sliding against Si 3 N 4 at room temperature and elevated temperatures up to 400 deg. C was comparatively studied. The microstructures and worn surface morphologies of the coatings were comparatively analyzed as well by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDXA). It was found that the as-sprayed WC-12%Co coatings were composed of WC as the major phase and W 2 C, WC 1-x , and W 3 Co 3 C as the minor phases. The plasma sprayed nanostructured WC-12%Co coating had much higher hardness and refined microstructures than the conventional WC-12%Co coating. This largely accounted for the better wear resistance of the nanostructured WC-12%Co coating than the conventional coating. Besides, the two types of WC-12%Co coatings showed minor differences in friction coefficients, though the nanostructured WC-12%Co coating roughly had slightly smaller friction coefficient than the conventional coating under the same sliding condition. Moreover, both the conventional and nanostructured WC-12%Co coatings recorded gradually increased wear rate with increasing temperature, and the nanostructured coating was less sensitive to the temperature rise in terms of the wear resistance. The worn surfaces of the conventional WC-12%Co coating at different sliding conditions showed more severe adhesion, microfracture, and peeling as compared to the nanostructured WC-12%Co coating, which well conformed to the corresponding wear resistance of the two types of coatings. The nanostructured WC-12%Co coating with a wear rate as small as 1.01 x 10 -7 mm 3 /Nm at 400 deg. C could be promising candidate coating for the surface-modification of some sliding components subject to harsh working conditions involving elevated

  11. Development of new physical activity and sedentary behavior change self-efficacy questionnaires using item response modeling

    Directory of Open Access Journals (Sweden)

    Venditti Elizabeth

    2009-03-01

    Full Text Available Abstract Background Theoretically, increased levels of physical activity self-efficacy (PASE should lead to increased physical activity, but few studies have reported this effect among youth. This failure may be at least partially attributable to measurement limitations. In this study, Item Response Modeling (IRM was used to develop new physical activity and sedentary behavior change self-efficacy scales. The validity of the new scales was compared with accelerometer assessments of physical activity and sedentary behavior. Methods New PASE and sedentary behavior change (TV viewing, computer video game use, and telephone use self-efficacy items were developed. The scales were completed by 714, 6th grade students in seven US cities. A limited number of participants (83 also wore an accelerometer for five days and provided at least 3 full days of complete data. The new scales were analyzed using Classical Test Theory (CTT and IRM; a reduced set of items was produced with IRM and correlated with accelerometer counts per minute and minutes of sedentary, light and moderate to vigorous activity per day after school. Results The PASE items discriminated between high and low levels of PASE. Full and reduced scales were weakly correlated (r = 0.18 with accelerometer counts per minute after school for boys, with comparable associations for girls. Weaker correlations were observed between PASE and minutes of moderate to vigorous activity (r = 0.09 – 0.11. The uni-dimensionality of the sedentary scales was established by both exploratory factor analysis and the fit of items to the underlying variable and reliability was assessed across the length of the underlying variable with some limitations. The reduced sedentary behavior scales had poor reliability. The full scales were moderately correlated with light intensity physical activity after school (r = 0.17 to 0.33 and sedentary behavior (r = -0.29 to -0.12 among the boys, but not for girls. Conclusion New

  12. Feasibility of retrofitting a university library with active workstations to reduce sedentary behavior.

    Science.gov (United States)

    Maeda, Hotaka; Quartiroli, Alessandro; Vos, Paul W; Carr, Lucas J; Mahar, Matthew T

    2014-05-01

    Libraries are an inherently sedentary environment, but are an understudied setting for sedentary behavior interventions. To investigate the feasibility of incorporating portable pedal machines in a university library to reduce sedentary behaviors. The 11-week intervention targeted students at a university library. Thirteen portable pedal machines were placed in the library. Four forms of prompts (e-mail, library website, advertisement monitors, and poster) encouraging pedal machine use were employed during the first 4 weeks. Pedal machine use was measured via automatic timers on each machine and momentary time sampling. Daily library visits were measured using a gate counter. Individualized data were measured by survey. Data were collected in fall 2012 and analyzed in 2013. Mean (SD) cumulative pedal time per day was 95.5 (66.1) minutes. One or more pedal machines were observed being used 15% of the time (N=589). Pedal machines were used at least once by 7% of students (n=527). Controlled for gate count, no linear change of pedal machine use across days was found (b=-0.1 minutes, p=0.75) and the presence of the prompts did not change daily pedal time (p=0.63). Seven of eight items that assessed attitudes toward the intervention supported intervention feasibility (plibrary with pedal machines to reduce sedentary behavior seems feasible, but improvement of its effectiveness is needed. This study could inform future studies aimed at reshaping traditionally sedentary settings to improve public health. Copyright © 2014 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  13. Dietary habits and sedentary behaviors among health science university students in Bahrain.

    Science.gov (United States)

    Musaiger, Abdulrahman O; Awadhalla, Muyssar S; Al-Mannai, Mariam; AlSawad, Muneera; Asokan, G V

    2017-04-01

    The aim of this study was to investigate the dietary patterns and sedentary behaviors among university students in Bahrain. A cross-sectional study was carried out with students of the College of Health Sciences in Bahrain using a self-reported questionnaire. All the students enrolled in this college were included in this study (642 students; 90 males and 552 females). The mean age of the sample was 20.1±2.0 years. A pre-tested questionnaire was used to collect information on the students' breakfast intake, snacking, food frequency intake, and sedentary habits. More than 50% of the students did not consume breakfast on a daily basis. A statistically significant difference (psleep; however, the only significant difference found was for Internet use (psleep for less time (students in Bahrain had unhealthy dietary habits and sedentary behaviors. Thus, an intervention program to promote healthy dietary patterns and lifestyle habits among university students is highly recommended.

  14. Moderate Activity and Fitness, Not Sedentary Time, Are Independently Associated with Cardio-Metabolic Risk in U.S. Adults Aged 18–49

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    Jeroen H. P. M. van der Velde

    2015-02-01

    Full Text Available This cross-sectional study is one of the first to examine and compare the independent associations of objectively measured sedentary time, moderate to vigorous physical activity (MVPA and fitness with cardio-metabolic risk factors. We studied 543 men and women (aged 18–49 years from the NHANES 2003–2004 survey. Sedentary time and MVPA were measured by accelerometry. Fitness was assessed with a submaximal treadmill test. Cardio-metabolic risk factors included: waist circumference (WC, BMI, blood pressure, fasting glucose, HDL- and non HDL cholesterol, triglycerides (TG, and C-reactive protein (CRP. Sedentary time, MVPA and fitness were used as predictors for the cardio-metabolic outcomes in a multiple regression analysis. Standardized regression coefficients were computed. Results show that sedentary time was associated with HDL-cholesterol (β = −0.080, p = 0.05 and TG (β = 0.080, p = 0.03. These results became non-significant after adjustment for MVPA and fitness. MVPA was associated with WC (β = −0.226, BMI (β = −0.239, TG (β = −0.108 and HDL-cholesterol (β = 0.144 (all p < 0.05. These results remained significant after adjustment for sedentary time and fitness. Fitness was associated with WC (β = −0.287, BMI (β = −0.266, systolic blood pressure (β = −0.159, TG (β = −0.092, and CRP (β = −0.130 (all p < 0.05. After adjustment for sedentary time and MVPA these results remained significant. These differences in relative importance of sedentary time, MVPA and fitness on cardio-metabolic-risk are important in the design of prevention programs. In this population, the strength of the associations between MVPA and fitness with cardio-metabolic markers appeared to be similar; both MVPA and fitness showed independent associations with cardio-metabolic risk factors. In contrast, sedentary time showed no independent associations with cardio-metabolic risk after correction for fitness and MVPA.

  15. Does Sedentary Behavior Predict Academic Performance in Adolescents or the Other Way Round? A Longitudinal Path Analysis.

    Science.gov (United States)

    Lizandra, Jorge; Devís-Devís, José; Pérez-Gimeno, Esther; Valencia-Peris, Alexandra; Peiró-Velert, Carmen

    2016-01-01

    This study examined whether adolescents' time spent on sedentary behaviors (academic, technological-based and social-based activities) was a better predictor of academic performance than the reverse. A cohort of 755 adolescents participated in a three-year period study. Structural Equation Modeling techniques were used to test plausible causal hypotheses. Four competing models were analyzed to determine which model best fitted the data. The Best Model was separately tested by gender. The Best Model showed that academic performance was a better predictor of sedentary behaviors than the other way round. It also indicated that students who obtained excellent academic results were more likely to succeed academically three years later. Moreover, adolescents who spent more time in the three different types of sedentary behaviors were more likely to engage longer in those sedentary behaviors after the three-year period. The better the adolescents performed academically, the less time they devoted to social-based activities and more to academic activities. An inverse relationship emerged between time dedicated to technological-based activities and academic sedentary activities. A moderating auto-regressive effect by gender indicated that boys were more likely to spend more time on technological-based activities three years later than girls. To conclude, previous academic performance predicts better sedentary behaviors three years later than the reverse. The positive longitudinal auto-regressive effects on the four variables under study reinforce the 'success breeds success' hypothesis, with academic performance and social-based activities emerging as the strongest ones. Technological-based activities showed a moderating effect by gender and a negative longitudinal association with academic activities that supports a displacement hypothesis. Other longitudinal and covariate effects reflect the complex relationships among sedentary behaviors and academic performance and the

  16. Perceived neighborhood safety related to physical activity but not recreational screen-based sedentary behavior in adolescents

    OpenAIRE

    Lenhart, Clare M.; Wiemken, Andrew; Hanlon, Alexandra; Perkett, Mackenzie; Patterson, Freda

    2017-01-01

    Abstract Background A growing proportion of adolescents have poor cardiovascular health behaviors, including low levels of physical activity and high levels of sedentary behavior, thus increasing the likelihood of poor heart health in later years. This study tested the hypothesis that low perceived neighborhood safety would be associated with low levels of physical activity and high levels of recreational sedentary behavior in high-school students. Methods Using cross-sectional, weighted data...

  17. Temporal and environmental patterns of sedentary and active behaviors during adolescents' leisure time.

    Science.gov (United States)

    Biddle, Stuart J H; Marshall, Simon J; Gorely, Trish; Cameron, Noel

    2009-01-01

    There is great interest in young people's overweight and obesity. Few data, however, describe when sedentary and physically active behaviors are likely to occur during the day or how these behaviors are related to location. The purpose of this study was to describe sedentary and active leisure-time behaviors of adolescents across the day and setting. Adolescents (male n = 579, female n = 967; aged 13-16 years) completed time-use diaries for three weekdays and one weekend day. At 15 min intervals, participants recorded what they were doing and where they were. TV viewing and sports/exercise peaked at different times in the day, although TV viewing was two to three times more likely to occur than sports/exercise. TV viewing was most likely to occur during the middle to late evening. The playing of computer games was low, particularly for girls. Weekend data showed TV viewing was the most reported activity throughout the day. For boys, "being in the garden" was highly predictive of engaging in sports/exercise, but this declined rapidly with age. Motorized travel to school was reported twice as often as active travel. Momentary assessments of behavior, in conjunction with contemporaneous reports of environmental factors, describe important patterns of leisure-time active and sedentary behaviors in youth.

  18. Quality of Life Profile, Overweight-Obesity and Sedentary Behavior in Elementary and High School Children of Guanacaste

    Directory of Open Access Journals (Sweden)

    Pedro Ureña-Bonilla

    2010-12-01

    Full Text Available The purpose of this study was to identify the quality of life profile, overweight-obesity and sedentary behavior in a group of elementary and high school children of Guanacaste. 635 students participated in the study. The participants completed a protocol by which they were anthropometrically evaluated, and also filled up a questionnaire related to sedentary behavior and quality of life. In general, the findings reflected a prevalence of overweight and obesity of 13, 9%. The most important sedentary activities were, in descending order, the small screen (watching TV, video games, computer, and certain social and cultural activities. The self-reported quality of life index was within acceptable limits but not exceeding 80 points on a scale of 1-100. There was no significant relationship between the rate of the overall quality of life, overweight, obesity and some sedentary behaviors, although some anthropometric parameters like percentage of body fat and body weight showed significant correlation with sedentary behavior and specific aspects belonging to quality of life. The study provides valuable information to health authorities, directors of educational institutions and parents about key issues related to child development.

  19. Obesity, Physical Activity, and Sedentary Behavior of Youth With Learning Disabilities and ADHD.

    Science.gov (United States)

    Cook, Bryan G; Li, Dongmei; Heinrich, Katie M

    2015-01-01

    Obesity, physical activity, and sedentary behavior in childhood are important indicators of present and future health and are associated with school-related outcomes such as academic achievement, behavior, peer relationships, and self-esteem. Using logistic regression models that controlled for gender, age, ethnicity/race, and socioeconomic status, we investigated the likelihood that youth with learning disabilities (LD) and attention-deficit/hyperactivity disorder (ADHD) are obese, physically active, and sedentary using a nationally representative sample of 45,897 youth in the United States from 10 to 17 years of age. Results indicated that youth with comorbid LD/ADHD were significantly more likely than peers without LD or ADHD to be obese; that youth with LD only, ADHD only, and comorbid LD/ADHD were significantly less likely to meet recommended levels of physical activity; and that youth with LD only were significantly more likely to exceed recommended levels of sedentary behavior. Medication status mediated outcomes for youth with ADHD. We offer school-based recommendations for improving health-related outcomes for students with LD and ADHD. © Hammill Institute on Disabilities 2014.

  20. Physical activity, sedentary behavior time and lipid levels in the Observation of Cardiovascular Risk Factors in Luxembourg study.

    Science.gov (United States)

    Crichton, Georgina E; Alkerwi, Ala'a

    2015-08-11

    Recently attention has been drawn to the health impacts of time spent engaging in sedentary behaviors. While many studies have investigated general physical activity (PA) in relation to blood lipid levels, the current study aimed to examine the intensity of activity, including sedentary behavior time, and time spent engaging in moderate and intense PA, with concentrations of HDL and LDL-cholesterol, total cholesterol, and triglycerides. Participants comprised 1331 individuals, aged 18 to 70 years, from the Observation of Cardiovascular Risk Factors in Luxembourg (ORISCAV-LUX) study, who underwent objective cardiovascular health assessments and completed the International Physical Activity Questionnaire (IPAQ). Time spent engaging in sedentary behaviors (screen time on a workday and a day off, and total sitting time on a work day), and moderate and intense PA, were related to levels of HDL and LDL-cholesterol, total cholesterol, and triglycerides. Analyses were conducted in the whole sample, and then with stratification according to BMI (normal weight versus overweight/obese). Both lower screen time during days off and higher intense PA time were significantly associated with higher HDL-cholesterol after full adjustment for socio-demographic factors, dietary factors and smoking (both p sedentary behavior time variables were observed (all p sedentary behavior time variable and lipid levels in those overweight or obese. Spending less time in sedentary behaviors, and engaging in medium levels of intense physical activity may be associated with a more favorable blood lipid profile, particularly with regard to levels of HDL and triglycerides.

  1. All-cause mortality risk as a function of sedentary behavior, moderate-to-vigorous physical activity and cardiorespiratory fitness.

    Science.gov (United States)

    Edwards, Meghan K; Loprinzi, Paul D

    2016-09-01

    Emerging work demonstrates individual associations of sedentary behavior, moderate-to-vigorous physical activity (MVPA) and cardiorespiratory fitness (CRF) on mortality risk. Limited research has evaluated all three of these parameters in a model when considering mortality risk, and their potential additive association on mortality risk has not been fully evaluated, which was the purpose of this study. Data from the 2003-2006 National Health and Nutrition Examination Survey were used (N = 2,295 adults 20-85 yrs), with follow-up through 2011. Sedentary behavior and MVPA were objectively assessed (accelerometry) with cardiorespiratory estimated from a prediction equation taking into consideration participant demographic, anthropometric and behavioral characteristics. Using the median values, a PACS (Physical Activity Cardiorespiratory Sedentary) score was created that ranged from 0-3, indicating the number of these three positive characteristics. Those with below median sedentary behavior did not have a reduced all-cause mortality risk (HR = 0.59; 95% CI: 0.34-1.04; P = 0.07), but those with above median MVPA (HR = 0.35; 95% CI: 0.15-0.82; P = 0.02) and above median CRF did (HR = 0.20; 95% CI: 0.09-0.43; P sedentary behavior, were independently associated with reduced mortality risk. Adults with all three characteristics (below median sedentary and above median MVPA and CRF), however, had the lowest mortality risk.

  2. Development of a consensus taxonomy of sedentary behaviors (SIT: report of Delphi Round 1.

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    Sebastien Francois Martin Chastin

    Full Text Available BACKGROUND: Over the last decade, sedentary behaviors have emerged as a distinctive behavioral paradigm with deleterious effects on health independent of physical activity. The next phase of research is to establish dose response between sedentary behaviors and health outcomes and improve understanding of context and determinants of these behaviors. Establishing a common taxonomy of these behaviors is a necessary step in this process. AIM: The Sedentary behavior International Taxonomy project was developed to establish a classification of sedentary behaviors by use of a formal consensus process. METHODS: The study follows a Delphi process in three Rounds. A preparatory stage informed the development of terms of reference documents. In Round 1, experts were asked to make statements about the taxonomy; 1 its purpose and use ; 2 the domains, categories or facets that should be consider and include; 3 the structure/architecture to arrange and link these domains and facets. In Round 2 experts will be presented with a draft taxonomy emerging from Round 1 and invited to comment and propose alterations. The taxonomy will then be finalised at the outset of this stage. RESULTS: Results of Round 1 are reported here. There is a general consensus that a taxonomy will help advances in research by facilitating systematic and standardised: 1 investigation and analysis; 2 reporting and communication; 3 data pooling, comparison and meta-analysis; 4 development of measurement tools; 4 data descriptions, leading to higher quality in data querying and facilitate discoveries. There is also a consensus that such a taxonomy should be flexible to accommodate diverse purposes of use, and future advances in the field and yet provide a cross-disciplinary common language. A consensual taxonomy structure emerged with nine primary facets (Purpose, Environment, Posture, Social, Measurement, Associated behavior, Status, Time, Type and the draft structure presented here for

  3. Urinary Estrogen Metabolites, Active and Sedentary Behaviors, and Breast Cancer Risk

    Science.gov (United States)

    A cross-sectional study of approximately 600 postmenopausal controls in the Breast Cancer Case-Control Study in Poland to assess urinary estrogen metabolites in relation to accelerometer-based measures of active and sedentary behaviors

  4. Physical Activity, Sedentary Behavior and the Risk of Overweight and Obesity in School-Aged Children.

    Science.gov (United States)

    Keane, Eimear; Li, Xia; Harrington, Janas M; Fitzgerald, Anthony P; Perry, Ivan J; Kearney, Patricia M

    2017-08-01

    Globally, public health policies are targeting modifiable lifestyle behaviors. We explore the independent association of moderate-to-vigorous physical activity (MVPA) and sedentary behavior on the risk of childhood overweight/obesity. A cross-sectional survey of children aged 8-11 years (N = 826). Objective body mass index was used to classify children as normal weight or overweight/obese. Children wore wrist-worn Geneactiv accelerometers for 7-days and thresholds were applied to categorize MVPA and sedentary time. Screen time (ST) was parent reported. Poisson regression examined the independent association of (1) MVPA (2), objective sedentary time and (3) ST on the risk of overweight/obesity. Overall, 23.7% (95% CI, 20.8-26.6%) of children were overweight/obese. On average, children spent 10.8% of waking time at MVPA and 61.3% sedentary. One-fifth (22.1%, 95% CI, 19.3-25.0%) of children achieved MVPA recommendations (≥ 60 min each day) and 17.5% (95% CI, 14.9-20.1%) met ST recommendations (overweight/obese independent of total sedentary time. Total time spent sedentary was not associated with overweight/obese independent of MVPA. ST was associated with an increased risk of overweight/obese independent of physical activity. Few schoolchildren met physical activity and screen time recommendations suggesting population based measures are needed.

  5. Objectively measured and self-reported leisure-time sedentary behavior and academic performance in youth: The UP&DOWN Study.

    Science.gov (United States)

    Esteban-Cornejo, Irene; Martinez-Gomez, David; Sallis, James F; Cabanas-Sánchez, Verónica; Fernández-Santos, Jorge; Castro-Piñero, Jose; Veiga, Oscar L

    2015-08-01

    To examine the associations of (i) objectively measured and self-reported sedentary behavior during leisure time with academic performance and (ii) patterns of sedentary behavior with academic performance. This study was conducted with 1146 youth aged 12.5±2.5years in Spain during 2011-2012. Leisure-time sedentary behavior during out-of-school hours was assessed by accelerometry and self-report. Academic performance was assessed through school grades. Objectively measured sedentary leisure-time was not significantly associated with academic performance. Time spent in Internet surfing, listening to music, and sitting without doing anything were negatively associated with all academic performance indicators (β ranging from -0.066 to -0.144; all pacademic indicators (β ranging from -0.085 to -0.148; all pacademic indicators (β ranging from 0.063 to 0.105; all pleisure-time, but not objectively measured sedentary leisure time, may influence academic performance. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Physical activity, sedentary behaviors and dietary habits among Saudi adolescents relative to age, gender and region.

    Science.gov (United States)

    Al-Hazzaa, Hazzaa M; Abahussain, Nada A; Al-Sobayel, Hana I; Qahwaji, Dina M; Musaiger, Abdulrahman O

    2011-12-21

    Few lifestyle factors have been simultaneously studied and reported for Saudi adolescents. Therefore, the purpose of the present study was to report on the prevalence of physical activity, sedentary behaviors and dietary habits among Saudi adolescents and to examine the interrelationships among these factors using representative samples drawn from three major cities in Saudi Arabia. This school-based cross-sectional study was conducted during the years 2009-2010 in three cities: Al-Khobar, Jeddah and Riyadh. The participants were 2908 secondary-school males (1401) and females (1507) aged 14-19 years, randomly selected using a multistage stratified sampling technique. Measurements included weight, height, sedentary behaviors (TV viewing, playing video games and computer use), physical activity using a validated questionnaire and dietary habits. A very high proportion (84% for males and 91.2% for females) of Saudi adolescents spent more than 2 hours on screen time daily and almost half of the males and three-quarters of the females did not meet daily physical activity guidelines. The majority of adolescents did not have a daily intake of breakfast, fruit, vegetables and milk. Females were significantly (p sedentary, much less physically active, especially with vigorous physical activity, and there were fewer days per week when they consumed breakfast, fruit, milk and diary products, sugar-sweetened drinks, fast foods and energy drinks than did males. However, the females' intake of French fries and potato chips, cakes and donuts, and candy and chocolate was significantly (p intake of breakfast, vegetables and fruit. Physical activity had a significant (p intake but not with sedentary behaviors. The high prevalence of sedentary behaviors, physical inactivity and unhealthy dietary habits among Saudi adolescents is a major public health concern. There is an urgent need for national policy promoting active living and healthy eating and reducing sedentary behaviors among

  7. Experimentally increasing sedentary behavior results in decreased life satisfaction

    Directory of Open Access Journals (Sweden)

    Meghan K. Edwards

    2017-03-01

    behavior-inducing randomized controlled intervention on life satisfaction. Methods: Active, young adults between the ages of 18-35 were recruited and randomly assigned into a sedentary behavior intervention group (n = 26 or a control group (n = 13. The intervention group participants were instructed to eliminate all exercise and restrict daily steps (as measured via pedometry to 5000 or less per day for one week. The control group was instructed to maintain regular levels of exercise and other physical activity for one week. Both groups completed the Satisfaction with Life Scale (SWLS pre-intervention and immediately post-intervention. Results: There was a significant group x time interaction (F = 32.75, P < 0.001, with post-hoc contrast tests indicating decreased SWLS score (indicating lower levels of life satisfaction in the intervention group during Visit 2 (post-intervention compared with Visit 1 (pre-intervention; this corresponded with a mean absolute (Visit 2 minus Visit 1 change of -8.58 (95% CI: -5.91, -11.24 for SWLS scores in the intervention group (31.1% reduction. Conclusion: A one-week sedentary behavior-inducing intervention may negatively impact life satisfaction in an active, young adult population. Regular physical activity may be imperative in avoiding negative life satisfaction-related consequences.

  8. Profiles of sedentary and non-sedentary young men ? a population-based MOPO study

    OpenAIRE

    Pyky, Riitta; Jauho, Anna-Maiju; Ahola, Riikka; Ik?heimo, Tiina M.; Koivumaa-Honkanen, Heli; M?ntysaari, Matti; J?ms?, Timo; Korpelainen, Raija

    2015-01-01

    Background Sedentary behavior is associated with poor well-being in youth with adverse trajectories spanning to adulthood. Still, its determinants are poorly known. Our aim was to profile sedentary and non-sedentary young men and to clarify their differences in a population-based setting. Methods A total of 616 men (mean age 17.9, SD 0.6) attending compulsory conscription for military service completed a questionnaire on health, health behavior, socioeconomic situation and media use. They und...

  9. Is spending time in screen-based sedentary behaviors associated with less physical activity: a cross national investigation

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    Iannotti Ronald J

    2010-05-01

    Full Text Available Abstract Background In Australia and the USA, national guidelines exist for limiting children's screen-exposure to two hours per day. This study aims to determine whether exceeding the suggested guidelines for screen-based sedentary behavior is associated with reduced levels of physical activity across different geographical regions. Methods Data material were taken from the 2005/2006 survey of "Health Behaviour in School-aged Children (HBSC study; A WHO cross-National Survey". Data were collected through questionnaires from 11-,13- and,15- year olds. The final sample included 200,615 adolescents from 39 different countries in Europe and North America. Gender and country stratified analyses regressed time spent in leisure-time vigorous physical activity (VPA and days of 60 minutes moderate to vigorous physical activity (MVPA on time spent in screen-based sedentary behaviors. To simplify interpretation, the estimates from each country were pooled using a meta-analytic procedure. Results Exceeding 2 hrs of daily total screen-time was negatively associated with MVPA for both boys and girls, and with VPA for girls. When investigating the different types of screen-based behaviors separately, exceeding 2 hrs daily of TV viewing was associated with less MVPA for both boys and girls and less VPA for girls. Gaming was associated with less MVPA and VPA for boys, and non-gaming computer use was associated with higher levels of VPA for both genders. Stronger negative associations between physical activity and screen-based sedentary behaviors were found in countries where mean levels of physical activity were relatively high. The association between physical activity and sedentary behavior was not significantly associated with national levels of screen-based sedentary behaviors. Conclusions The displacement mechanism does not appear to be universal across countries. On a national level, negative associations between physical activity and screen

  10. Prevalence of physical activity and sedentary behavior among stroke survivors in the United States.

    Science.gov (United States)

    Butler, Eboneé N; Evenson, Kelly R

    2014-01-01

    The risk of stroke is greatest among adults who have experienced a previous stroke, transient ischemic attack, or myocardial infarction. Physical activity may reduce the secondary risk of stroke through mediating effects on blood pressure, vasoconstriction, and circulating lipid concentrations; however, little is known about the prevalence of physical activity and sedentary behavior among stroke survivors in the United States. Using data from the National Health and Nutrition Examination Survey (NHANES), we describe self-reported and objectively measured physical activity and sedentary behavior among adults with a self-reported history of stroke. We also contrast physical activity among stroke survivors with that of adults without stroke (unexposed) to illustrate expected behavior in the absence of disease. Fewer participants with stroke met weekly physical activity guidelines as outlined in the 2008 Physical Activity Guidelines for Americans when compared with unexposed participants (17.9% vs 25.0%) according to self-reported data. In addition, participants with stroke reported less moderate (46.1% vs 54.7%) and vigorous (9.1% vs 19.6%) leisure activity compared with unexposed participants. As measured by accelerometer, time since diagnosis was inversely associated with physical activity engagement, and participants with stroke recorded more daily hours of sedentary behavior compared with unexposed participants (10.1 hours vs 8.9 hours). Findings from this study provide a basis for future work seeking to measure the impact of physical activity on the secondary prevention of stroke by characterizing the prevalence of physical activity and sedentary behavior among stroke survivors in the United States.

  11. Associations between screen-based sedentary behavior and cardiovascular disease risk factors in Korean youth.

    Science.gov (United States)

    Byun, Wonwoo; Dowda, Marsha; Pate, Russell R

    2012-04-01

    The purposes of this study were to: 1) describe the patterns of screen-based sedentary behaviors, and 2) examine the association between screen-based sedentary behavior and cardiovascular disease (CVD) risk factors in representative Korean children and adolescents, aged 12 to 18 yr, in the Korean National Health and Nutrition Examination Survey. Screen-based sedentary behavior was measured using self-report questionnaires that included items for time spent watching TV and playing PC/video games. Physical activity was measured using items for frequency and duration of moderate-to-vigorous physical activity (MVPA). CVD risk factors such as body mass index (BMI), waist circumference, LDL cholesterol, HDL cholesterol, total cholesterol, triglycerides, glucose, systolic blood pressure, and diastolic blood pressure were measured. Boys spent more time playing PC/video games, and girls spent more time watching TV. After adjusting for age, gender, annual household income, and MVPA, an additional hour of watching TV was significantly associated with the risk of overweight (OR 1.17 [95% CI 1.03-1.33]), high abdominal adiposity (OR 1.27 [1.06-1.51]), and low HDL cholesterol (OR 1.27 [1.10-1.47]). An additional hour spent playing PC/video games also increased the risk of high abdominal adiposity (OR 1.20 [1.03-1.40]). Prospective observations and interventions are needed to determine causal relationships between screen-based sedentary behavior and CVD risk profiles in Korean youth.

  12. Social support, physical activity and sedentary behavior among 6th-grade girls: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Hoelscher Deanna M

    2006-04-01

    Full Text Available Abstract Background Despite the importance of social support in promoting physical activity, little is known about the relative influence of the type or source of social support on adolescent girls' physical activity and sedentary behaviors. This study examined the associations of two types of social support (social participation in and social encouragement for physical activity and two social support sources (family and friends with self-reported daily minutes of physical activity and sedentary behavior among sixth-grade girls in Texas. Methods A secondary analysis of 718 sixth-grade girls between the ages of 10 to 14 was performed using cross-sectional baseline data from an osteoporosis prevention intervention study. Physical activity and sedentary behaviors (television-video viewing and computer-video game playing were assessed using 3 administrations of the Self-Administered Physical Activity Checklist; social support indicators were assessed with Likert-type items from a psychosocial questionnaire. Results In multiple linear regression analyses, friend physical activity participation (partial correlation coefficient (r = 0.10, p = .009 and friend (r = 0.12 and family encouragement (r = 0.11 (p Conclusion Findings lend support to the importance of social support for physical activity among adolescent girls but suggest that the source and type of social support may differ for physical activity and sedentary behaviors. Further research is needed to assess the causal or reciprocal relation between the roles of friends and family in promoting physical activity and of family physical activity in decreasing sedentary behaviors among early adolescent girls.

  13. Physical activity and sedentary behavior during the early years in Canada: a cross-sectional study

    Science.gov (United States)

    2013-01-01

    Background Physical activity and sedentary behavior habits are established during early childhood, yet only recently has objectively measured data been available on children aged 5 years and younger. This study presents data on the physical activity and sedentary behaviors of Canadian children aged 3–5 years. Methods Data were collected as part of the Canadian Health Measures Survey between 2009 and 2011. A nationally-representative sample (n = 459) of children aged 3–5 years wore Actical accelerometers during their waking hours for 7 consecutive days. Data were collected in 60-sec epochs and respondents with ≥4 valid days were retained for analysis. Parents reported their child’s physical activity and screen time habits in a questionnaire. Results Eighty-four percent of 3–4 year old children met the physical activity guideline of 180 minutes of total physical activity every day while 18% met the screen time target of physical activity guideline of 60 minutes of daily moderate-to-vigorous physical activity (MVPA) while 81% met the screen time target of physical activity and 66 minutes of MVPA while 5 year old children accumulated an average of 342 min/d of total physical activity and 68 minutes of MVPA. Children were sedentary for approximately half of their waking hours and spent an average of 2 hours per day in front of screens. Only 15% of 3–4 year olds and 5% of 5 year olds are meeting both the physical activity and sedentary behavior guidelines. Conclusions Promoting physical activity while reducing sedentary behavior is important at all stages of life. The findings of the present study indicate that there remains significant room for improvement in these behaviors among young Canadian children. PMID:23642258

  14. Erosion-oxidation behavior of thermal sprayed Ni20Cr alloy and WC and Cr3C2 cermet coatings

    Directory of Open Access Journals (Sweden)

    Clarice Terui Kunioshi

    2005-06-01

    Full Text Available An apparatus to conduct high temperature erosion-oxidation studies up to 850 °C and with particle impact velocities up to 15 m.s-1 was designed and constructed in the Corrosion Laboratories of IPEN. The erosion-oxidation behavior of high velocity oxy fuel (HVOF sprayed alloy and cermet coatings of Ni20Cr, WC 20Cr7Ni and Cr3C2 Ni20Cr on a steel substrate has been studied. Details of this apparatus and the erosion-oxidation behavior of these coatings are presented and discussed. The erosion-oxidation behavior of HVOF coated Cr3C2 25(Ni20Cr was better than that of WC 20Cr7Ni, and the erosion-oxidation regimes have been identified for these coatings at particle impact velocity of 3.5 m.s-1, impact angle of 90° and temperatures in the range 500 to 850 °C.

  15. Comparison of physical activity, sedentary behavior and physical fitness between fulltime and part-time students

    Directory of Open Access Journals (Sweden)

    Waynne Ferreira de Faria

    2015-07-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n4p418   The aim of this study was to compare physical activity, sedentary behavior and physical fitness between full-time and part-time students. The sample consisted of 72 students (9 to 12 years, 34 of them studying full time. The subjects answered a questionnaire about physical activity, sedentary behavior, and sociodemographic characteristics. Data regarding sexual maturation, body composition and physical fitness were also collected. The results showed that girls studying full time spent less time per day in sedentary behavior compared to part-time girls (p<0.05. Analysis of anthropometric variables showed a significantly lower body fat percentage in boys studying full time. With respect to the physical fitness tests, significant differences were identified in the sit and reach test, horizontal jump, medicine ball throw and agility, with the observation of higher performance in full-time students. Similarly, girls studying full time exhibited significantly higher performance in the horizontal jump and agility tests compared to their peers. It can be concluded that full-time students spend less time in sedentary behavior and exhibit better physical fitness indices in most of the tests used, irrespective of gender.

  16. Patterns of screen-based sedentary behavior and physical activity and associations with overweight among Norwegian adolescents: a latent profile approach

    Directory of Open Access Journals (Sweden)

    Ole Melkevik

    2011-03-01

    Full Text Available Background: Physical activity and screen based sedentary behaviors are both related to energy balance and to risk for becoming overweight. The aim of this study is to find out if these behaviors cluster together in order to find out whether groups of adolescents have particularly unfortunate levels of both physical activity and screen-based sedentary behaviors. Methods: Data are from the Norwegian 2005/2006 sample of the international "Health Behaviour in School-aged Children (HBSC study; A WHO cross-National Survey". Data were collected through questionnaires from 13-, 15- and 16-year-olds. The final sample included 4848 adolescents. Gender-stratified latent profile analysis was used to identify the different profiles. Results: Six profiles were identified for both boys and girls. Less than 30% of adolescents were found to have behavioral patterns which were associated with higher risk for overweight relative to the most healthy behavioral profile. Physical activity and screen-based sedentary behaviors cluster together in different ways suggesting independence between the behaviors. Low levels of physical activity was the most important predictor for overweight among boys. Screen-based sedentary behaviors were more important predictors of overweight among girls. Conclusions: Physical activity and screen-based sedentary behaviors are independent behaviors and may cluster together in manners which lead to low energy expenditure and subsequent increased risk for overweight among adolescents.

  17. Tribological Behavior of Multilayered WC-Ti1-xAlxN Coatings Deposited by Cathodic Arc Deposition Process on High Speed Steel

    International Nuclear Information System (INIS)

    Kim, Jung Gu; Hwang, Woon Suk

    2006-01-01

    Recently, much of the current development in surface modification engineering are focused on multilayered coatings. Multilayered coatings have the potential to improve the tribological properties. Four different multilayered coatings were deposited on AISI D2 steel. The prepared samples are designed as WC-Ti 0.6 Al 0.4 N, WC-Ti 0.53 Al 0.47 N, WC-Ti 0.5 Al 0.5 N and WC-Ti 0.43 Al 0.57 N. The multilayered coatings were investigated with respect to coating surface and cross-sectional morphology, roughness, adhesion, hardness, porosity and tribological behavior. Especially, wear tests of four multilayered coatings were preformed by using a ball-on-disc configuration with a linear sliding speed of 0.017 m/sec, 5.38 N load. The tests were carried out at room temperature in air by employing AISI 52100 steel ball (H R = 66) having a diameter of 10 mm. The surface morphology, and topography of the wear scars of samples and balls have been determined by using scanning electron spectroscopy (SEM). Results have showed an improved wear resistance of the WC-Ti 1-x 6Al x N coatings with increasing of Al concentration. WC-Ti 0.43 Al 0.57 N coating with the lower surface roughness and porosity with good adhesion enhanced wear resistance

  18. Technologies That Assess the Location of Physical Activity and Sedentary Behavior: A Systematic Review.

    Science.gov (United States)

    Loveday, Adam; Sherar, Lauren B; Sanders, James P; Sanderson, Paul W; Esliger, Dale W

    2015-08-05

    The location in which physical activity and sedentary behavior are performed can provide valuable behavioral information, both in isolation and synergistically with other areas of physical activity and sedentary behavior research. Global positioning systems (GPS) have been used in physical activity research to identify outdoor location; however, while GPS can receive signals in certain indoor environments, it is not able to provide room- or subroom-level location. On average, adults spend a high proportion of their time indoors. A measure of indoor location would, therefore, provide valuable behavioral information. This systematic review sought to identify and critique technology which has been or could be used to assess the location of physical activity and sedentary behavior. To identify published research papers, four electronic databases were searched using key terms built around behavior, technology, and location. To be eligible for inclusion, papers were required to be published in English and describe a wearable or portable technology or device capable of measuring location. Searches were performed up to February 4, 2015. This was supplemented by backward and forward reference searching. In an attempt to include novel devices which may not yet have made their way into the published research, searches were also performed using three Internet search engines. Specialized software was used to download search results and thus mitigate the potential pitfalls of changing search algorithms. A total of 188 research papers met the inclusion criteria. Global positioning systems were the most widely used location technology in the published research, followed by wearable cameras, and radio-frequency identification. Internet search engines identified 81 global positioning systems, 35 real-time locating systems, and 21 wearable cameras. Real-time locating systems determine the indoor location of a wearable tag via the known location of reference nodes. Although the type

  19. Lacto-Vegetarian Diet and Correlation of Fasting Blood Sugar with Lipids in Population Practicing Sedentary Lifestyle.

    Science.gov (United States)

    Praharaj, Ardhendu Bhusan; Goenka, Ramesh Kumar; Dixit, Sujata; Gupta, Manoj Kumar; Kar, Shantanu Kumar; Negi, Sapna

    2017-01-01

    Rising burden of diabetes in India requires quick intervention that integrates policies and programs for effective prevention and control of disease. This retrospective cross-sectional study was conducted to observe effect of diet in two Indian communities practicing sedentary lifestyle. Fasting blood samples were analyzed for blood sugar, glycated-hemoglobin (HbA1C), and lipid profile. Body mass index (BMI) and waist circumference (WC) measurements were recorded. Diabetes incidence was lower in lacto-vegetarian (1.7%) than in non-vegetarian group (5.3%) despite similar lipid profiles and BMI/WC between the groups. Fasting blood sugar (FBS) was positively correlated with LDL and VLDL levels and negatively correlated with HDL, only in lacto-vegetarian group. Study suggests: (1) Indian lacto-vegetarian diet has beneficial effects on diabetes incidence irrespective of high body weight and sedentary lifestyle; (2) intervention to reduce body lipids, such as lipid-lowering drugs and exercise, may have greater effect in reducing FBS levels in this lacto-vegetarian group.

  20. Sensitivity to Change of Objectively-Derived Measures of Sedentary Behavior

    Science.gov (United States)

    Chastin, Sebastien F. M.; Winkler, Elisabeth A. H.; Eakin, Elizabeth G.; Gardiner, Paul A.; Dunstan, David W.; Owen, Neville; Healy, Genevieve N.

    2015-01-01

    The aim of this study was to examine the sensitivity to change of measures of sedentary behavior derived from body worn sensors in different intervention designs. Results from two intervention studies: "Stand up for Your Health" (pre-post home-based study with older adults not in paid employment) and "Stand Up Comcare"…

  1. Physical activity and sedentary behavior in metabolically healthy obese young women

    Science.gov (United States)

    Studies of physical activity (PA) and sedentary behavior (SB) in metabolically healthy obese (MHO) have been limited to postmenopausal white women. We sought to determine whether PA and SB differ between MHO and metabolically abnormal obese (MAO), in young black and white women....

  2. Mobility disability and the pattern of accelerometer-derived sedentary and physical activity behaviors in people with multiple sclerosis

    Science.gov (United States)

    Ezeugwu, Victor; Klaren, Rachel E.; A. Hubbard, Elizabeth; Manns, Patricia (Trish); Motl, Robert W.

    2015-01-01

    Objective Low physical activity and high sedentary behavior levels are major concerns in persons with multiple sclerosis (MS) and these differ depending on the level of mobility disability. However, the manner in which daily activity is accumulated is currently unknown in this population. Methods A secondary analysis was performed on a combined data set of persons with MS from two previous investigations of physical activity and symptomatic or quality of life outcomes in the United States over a two year period (2007–2009). Mobility disability status was determined using the Patient Determined Disease Steps (PDDS) while activity behavior was objectively monitored using an ActiGraph accelerometer for 7 days. Results Persons with MS who have mobility disability were involved in sedentary behavior, light and moderate intensity activity for 65%, 34% and 1% of the day, respectively compared to 60%, 37%, and 3%, respectively in those without mobility disability (p mobility disability status. Compared to those without mobility disability, the average number of sedentary bouts longer than 30 min was greater in those with mobility disability (p = 0.016). Conclusion Persons with MS with mobility disability are less active, engage in more sedentary behavior and accumulate prolonged sedentary bouts. PMID:26844077

  3. Wear resistance and fracture mechanics of WC-Co composites

    International Nuclear Information System (INIS)

    Kaytbay, Saleh; El-Hadek, Medhat

    2014-01-01

    Manufacturing of WC-Co composites using the electroless precipitation method at different sintering temperatures of 1 100, 1 250, 1 350 and 1 500 C was successfully achieved. The chemical composition of the investigated materials was 90 wt.% WC with 10 wt.% Co, and 80 wt.% WC with 20 wt.% Co. The specific density, densification, and Vickers microhardness measurements were found to increase with increased sintering temperature for both the WC-Co compositions. The composites of tungsten carbide with 10 wt.% Co had a higher specific density and Vickers microhardness measurements than those for the composites of tungsten carbide with 20 wt.% Co. Composites with WC-10 wt.% Co had better wear resistance. The stress-strain and transverse rupture strength increased monotonically with the increase in sintering temperatures, agreeing with the material hardness and wear resistance behavior. Fractographical scanning electron microscopy analysis of the fracture surface demonstrated a rough characteristic conical shape failure in the direction of the maximum shear stress. A proposed mechanism for the formation of the conical fracture surface under compression testing is presented. (orig.)

  4. Sedentary leisure time behavior, snacking habits and cardiovascular biomarkers: the Inter99 Study

    DEFF Research Database (Denmark)

    Frydenlund, Gitte; Jørgensen, Torben; Toft, Ulla

    2011-01-01

    Aim: To explore the association between sedentary leisure time behavior (SLTB) and cardiovascular biomarkers, taking into account snacking habits, alcohol intake and physical activity level. Design: Cross-sectional. Methods: Study participants were recruited from the 5-year follow-up of a populat......Aim: To explore the association between sedentary leisure time behavior (SLTB) and cardiovascular biomarkers, taking into account snacking habits, alcohol intake and physical activity level. Design: Cross-sectional. Methods: Study participants were recruited from the 5-year follow...... non-significant in men (ß = 0.9924, [0.9839; 1.0011]) and women (ß = 0.9932, [0.8605; 1.0014]). Conclusion: SLTB appears to be an independent CVD risk factor, regardless of snacking habits and physical activity....

  5. Bidirectional associations between activity-related parenting practices, and child physical activity, sedentary screen-based behavior and body mass index: a longitudinal analysis.

    Science.gov (United States)

    Sleddens, Ester F C; Gubbels, Jessica S; Kremers, Stef P J; van der Plas, Eline; Thijs, Carel

    2017-07-06

    It has been generally assumed that activity-related parenting practices influence children's activity behavior and weight status. However, vice versa parents may also change their parenting behaviors in response to their perceptions of their child's activity behavior and weight status. This study examined the bidirectional relationships between activity-related parenting practices, and physical activity, sedentary screen-based behavior, and body mass index (BMI) between children's age of 5 and 7 years. Three scales of the Activity-related Parenting Questionnaire (i.e. 'restriction of sedentary behavior', 'stimulation of physical activity', and 'monitoring of physical activity') were completed by 1694 parents of the Dutch KOALA Birth Cohort Study at the child's age of around 5 and again around age 7. Physical activity, sedentary screen-based behavior and BMI were measured at both ages as well. Linear regression models were used to estimate the bidirectional associations between each parenting practice and the child's physical activity levels, sedentary screen-based behavior and BMI z-scores. Several parenting practices at age 5 predicted child physical activity, sedentary screen-based behavior, and BMI z-scores at age 7. Restriction of sedentary behavior positively predicted child BMI and sedentary screen-based behavior, whereas this practice negatively predicted child physical activity. In addition, stimulation of physical activity at age 5 was significantly associated with higher levels of child physical activity at age 7. The following child factors at age 5 predicted parenting practices at age 7: Child physical activity positively predicted parental stimulation of physical activity and monitoring activities. Sedentary screen-based behavior was associated with lower parental stimulation to be active. Findings generally revealed that parents and children mutually influence each other's behavior. A reinforcing feedback loop was present between parental stimulation

  6. Cyclic oxidation behavior of plasma sprayed NiCrAlY/WC-Co/cenosphere coating

    Science.gov (United States)

    Mathapati, Mahantayya; Ramesh M., R.; Doddamani, Mrityunjay

    2018-04-01

    Components working at elevated temperature like boiler tubes of coal and gas fired power generation plants, blades of gas and steam turbines etc. experience degradation owing to oxidation. Oxidation resistance of such components can be increased by developing protective coatings. In the present investigation NiCrAlY-WC-Co/Cenosphere coating is deposited on MDN 321 steel substrate using plasma spray coating. Thermo cyclic oxidation behavior of coating and substrate is studied in static air at 600 °C for 20 cycles. The thermo gravimetric technique is used to approximate the kinetics of oxidation. X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray mapping techniques are used to characterize the oxidized samples. NiCrAlY-WC-Co/Cenosphere coating exhibited lower oxidation rate in comparison to MDN 321 steel substrate. The lower oxidation rate of coating is attributed to formation of Al2O3, Cr2O3, NiO and CoWO4 oxides on the outermost surface.

  7. Sleep Duration, Sedentary Behavior, Physical Activity, and Quality of Life after Inpatient Stroke Rehabilitation.

    Science.gov (United States)

    Ezeugwu, Victor E; Manns, Patricia J

    2017-09-01

    The aim of this study was to describe accelerometer-derived sleep duration, sedentary behavior, physical activity, and quality of life and their association with demographic and clinical factors within the first month after inpatient stroke rehabilitation. Thirty people with stroke (mean ± standard deviation, age: 63.8 ± 12.3 years, time since stroke: 3.6 ± 1.1 months) wore an activPAL3 Micro accelerometer (PAL Technologies, Glasgow, Scotland) continuously for 7 days to measure whole-day activity behavior. The Stroke Impact Scale and the Functional Independence Measure were used to assess quality of life and function, respectively. Sleep duration ranged from 6.6 to 11.6 hours/day. Fifteen participants engaged in long sleep greater than 9 hours/day. Participants spent 74.8% of waking hours in sedentary behavior, 17.9% standing, and 7.3% stepping. Of stepping time, only a median of 1.1 (interquartile range: .3-5.8) minutes were spent walking at a moderate-to-vigorous intensity (≥100 steps/minute). The time spent sedentary, the stepping time, and the number of steps differed significantly by the hemiparetic side (P stroke. There were moderate to strong correlations between the stepping time and the number of steps with gait speed (Spearman r = .49 and .61 respectively, P stroke, and cognition were not significant. People with stroke sleep for longer than the normal duration, spend about three quarters of their waking hours in sedentary behaviors, and engage in minimal walking following stroke rehabilitation. Our findings provide a rationale for the development of behavior change strategies after stroke. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  8. Health-related quality of life, adiposity, and sedentary behavior in patients with early schizophrenia: preliminary study

    Directory of Open Access Journals (Sweden)

    Strassnig M

    2012-10-01

    Full Text Available Martin Strassnig,1 Jaspreet S Brar,2 Rohan Ganguli31Department of Psychiatry, Miller School of Medicine, University of Miami, Miami, FL, USA; 2Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA; 3Department of Psychiatry, Centre for Addiction and Mental Health, University of Toronto, Toronto, ON, CanadaObjective: To examine adiposity and sedentary behavior in relation to health-related quality of life (QoL in patients with early schizophrenia.Methods: A cross-sectional study was used to assess adiposity by dual-energy X-ray absorptiometry scans, habitual physical activity and idle sitting time by the Short Form International Physical Activity Questionnaire, and health-related QoL by the RAND Medical Outcomes Study SF-36. QoL scores were compared with age-adjusted Canadian normative population data.Results: There were 36 participants with early schizophrenia, average age 25.1 (±3.6. Twenty-nine (72.5% were males. Mean illness duration was 30 (±18 months, and mean body mass index was 28.3 (±5. Females had higher body fat content than males (30.8 ± 6.9 vs 24.7 ± 10.6; t = −2.6, df = 34; P = 0.015. Total body fat (F = 14; P = 0.001, lean body mass (F = 10.2; P = 0.001, and sedentary behavior (F = 5; P = 0.013 significantly increased across body mass index categories. Total body fat was correlated with sedentary behavior (r = 0.62; P = 0.001, and total lean body mass was negatively correlated with sedentary behavior (r = 0.39; P = 0.03. Based on SF-36 scores, participants had significantly lower physical functioning (P = 0.0034, role physical (P = 0.0003, general health (P < 0.0001, vitality (P = 0.03, and physical component scores (P = 0.003 than Canadian population comparisons. Habitual sedentary behavior, more than activity or adiposity levels, was associated with health-related QoL in early schizophrenia.Conclusion: Health-related QoL is lower in early schizophrenia and is predominantly experienced in the physical

  9. Obesity, Physical Activity, and Sedentary Behavior of Youth with Learning Disabilities and ADHD

    Science.gov (United States)

    Cook, Bryan G.; Li, Dongmei; Heinrich, Katie M.

    2015-01-01

    Obesity, physical activity, and sedentary behavior in childhood are important indicators of present and future health and are associated with school-related outcomes such as academic achievement, behavior, peer relationships, and self-esteem. Using logistic regression models that controlled for gender, age, ethnicity/race, and socioeconomic…

  10. Slurry Erosion Behavior of F6NM Stainless Steel and High-Velocity Oxygen Fuel-Sprayed WC-10Co-4Cr Coating

    Science.gov (United States)

    Cui, S. Y.; Miao, Q.; Liang, W. P.; Huang, B. Z.; Ding, Z.; Chen, B. W.

    2017-02-01

    WC-10Co-4Cr coating was applied to the surface of F6NM stainless steel by high-velocity oxygen-fuel spraying. The slurry erosion behavior of the matrix and coating was examined at different rotational speeds using a self-made machine. This experiment effectively simulates real slurry erosion in an environment with high silt load. At low velocity (<6 m/s), the main failure mechanism was cavitation. Small bubbles acted as an air cushion, obstructing direct contact between sand and the matrix surface. However, at velocity above 9 m/s, abrasive wear was the dominant failure mechanism. The results indicate that WC-10Co-4Cr coating significantly improved the slurry resistance at higher velocity, because it created a thin and dense WC coating on the surface.

  11. Sedentary Behavior Is Independently Related to Fat Mass among Children and Adolescents in South China.

    Science.gov (United States)

    Xue, Hongmei; Tian, Guo; Duan, Ruonan; Quan, Liming; Zhao, Li; Yang, Min; Libuda, Lars; Muckelbauer, Rebecca; Cheng, Guo

    2016-10-25

    We aim to explore the independent associations of sedentary behaviors (SB) with body mass distribution among Chinese children. Data on the screen-based sedentary time (television viewing and computer use) and doing homework, physical activities and dietary intake of 1586 Chinese children (50.3% girls) aged 7-15 years were obtained through validated questionnaires. Skin-fold thickness, body height, and weight were measured to calculate percent body fat (%BF), fat mass index (FMI), and fat-free mass index (FFMI). Parental characteristics were collected by questionnaires. Among girls, time of SB (screen time or doing homework) was positively related to %BF, FMI, and FFMI ( p 0.09), while time of doing homework was positively related to %BF and FMI ( p = 0.03). Sedentary behaviors might be positively and independently related to fat mass among Chinese children, and were more pronounced in girls.

  12. The effects of a pedometer-based behavioral modification program with telephone support on physical activity and sedentary behavior in type 2 diabetes patients.

    Science.gov (United States)

    De Greef, Karlijn P; Deforche, Benedicte I; Ruige, Johannes B; Bouckaert, Jacques J; Tudor-Locke, Catrine E; Kaufman, Jean-Marc; De Bourdeaudhuij, Ilse M

    2011-08-01

    Effectiveness of a behavioral modification program on physical activity (PA) and sedentary behavior in diabetes patients. Ninety-two patients were randomly assigned to an intervention or control group. The 24-weeks intervention consisted of a face-to-face session, pedometer and seven telephone follow-ups. Mean selection criteria were 35-75 years; 25-35 kg/m(2); ≤ 12% HbA1c, treated for type 2 diabetes; no PA limitations. PA and sedentary behavior were measured by pedometer, accelerometer and questionnaire over the short- (24 weeks) and intermediate- (1 year) term. The intervention group increased their steps/day by 2744, their total PA by 23 min/day (pbehavior by 23 min/day (pbehavior (pbehavioral modification program with telephone support showed lasting positive effects on steps/day, PA and sedentary behavior. This study tested a convenient way to increase PA among type 2 diabetes patients. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  13. 24 Hours of Sleep, Sedentary Behavior, and Physical Activity with Nine Wearable Devices

    Science.gov (United States)

    Rosenberger, Mary E.; Buman, Matthew P.; Haskell, William L.; McConnell, Michael V.; Carstensen, Laura L.

    2015-01-01

    Getting enough sleep, exercising and limiting sedentary activities can greatly contribute to disease prevention and overall health and longevity. Measuring the full 24-hour activity cycle - sleep, sedentary behavior (SED), light intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) - may now be feasible using small wearable devices. PURPOSE This study compares nine devices for accuracy in 24-hour activity measurement. METHODS Adults (N=40, 47% male) wore nine devices for 24-hours: Actigraph GT3X+, activPAL, Fitbit One, GENEactiv, Jawbone Up, LUMOback, Nike Fuelband, Omron pedometer, and Z-Machine. Comparisons (to standards) were made for total sleep time (Z-machine), time spent in SED (activPAL), LPA (GT3x+), MVPA (GT3x+), and steps (Omron). Analysis included mean absolute percent error, equivalence testing, and Bland-Altman plots. RESULTS Error rates ranged from 8.1–16.9% for sleep; 9.5–65.8% for SED; 19.7–28.0% for LPA; 51.8–92% for MVPA; and 14.1–29.9% for steps. Equivalence testing indicated only two comparisons were significantly equivalent to standards: the LUMOback for sedentary behavior and the GT3X+ for sleep. Bland-Altman plots indicated GT3X+ had the closest measurement for sleep, LUMOback for sedentary behavior, GENEactiv for LPA, Fitbit for MVPA and GT3X+ for steps. CONCLUSIONS Currently, no device accurately captures activity data across the entire 24-hour day, but the future of activity measurement should aim for accurate 24-hour measurement as a goal. Researchers should continue to select measurement devices based on their primary outcomes of interest. PMID:26484953

  14. Physical Activity, Sedentary Behavior, and Symptoms of Major Depression in Middle Childhood.

    Science.gov (United States)

    Zahl, Tonje; Steinsbekk, Silje; Wichstrøm, Lars

    2017-02-01

    The prospective relation between physical activity and Diagnostic and Statistical Manual of Mental Disorders-defined major depression in middle childhood is unknown, as is the stability of depression. We therefore aimed to (1) determine whether there are reciprocal relations between moderate-to-vigorous physical activity (MVPA) and sedentary behavior, on one hand, and Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition defined symptoms of major depressive disorder, on the other and (2) assess the extent of stability in depressive symptoms from age 6 to 10 years. A community sample of children living in Trondheim, Norway, comprising a total of 795 6-year-old children was followed up at 8 (n = 699) and 10 (n = 702) years of age. Physical activity was recorded by accelerometry and symptoms of major depression were measured through semistructured clinical interviews of parents and children. Bidirectional relationships between MVPA, sedentary activity, and symptoms of depression were analyzed through autoregressive cross-lagged models, and adjusted for symptoms of comorbid psychiatric disorders and BMI. At both age 6 and 8 years, higher MVPA predicted fewer symptoms of major depressive disorders 2 years later. Sedentary behavior did not predict depression, and depression predicted neither MVPA nor sedentary activity. The number of symptoms of major depression declined from ages 6 to 8 years and evidenced modest continuity. MVPA predicts fewer symptoms of major depression in middle childhood, and increasing MVPA may serve as a complementary method to prevent and treat childhood depression. Copyright © 2017 by the American Academy of Pediatrics.

  15. Observation of WC grain shapes determined by carbon content during liquid phase sintering of WC-Co alloys

    International Nuclear Information System (INIS)

    Sona Kim; Hyoun-Ee Kim; Seok-Hee Han; Jong-Ku Park

    2001-01-01

    In the composite materials of WC-Co alloys, the faceted WC grains as a hard phase are dispersed in the ductile matrix of cobalt. Properties of WC-Co alloys are affected by microstructural factors such as volume fraction of WC phase, size of WC grains, and carbon content (kinds of constituent phases). Although the properties of WC-Co alloys are inevitably affected by the shape of WC grains, the shape of WC grains has not been thrown light on the properties of WC-Co alloys yet, because it has been regarded to have a uniform shape regardless of alloy compositions. It is proved that the WC grains have various shapes varying reversibly with carbon content in the sintered WC-Co compacts. This dependency of grain shape on the carbon content is attributed to asymmetric atomic structure of WC crystal. The {10 1 - 0} prismatic planes are distinguished into two groups with different surface energy according to their atomic structures. The prismatic planes of high surface energy tend to disappear in the compacts with high carbon content. In addition, these high energy prismatic planes tend to split into low energy surfaces in the large WC grains. (author)

  16. Extracting objective estimates of sedentary behavior from accelerometer data: measurement considerations for surveillance and research applications.

    Directory of Open Access Journals (Sweden)

    Youngdeok Kim

    Full Text Available Accelerometer-based activity monitors are widely used in research and surveillance applications for quantifying sedentary behavior (SB and physical activity (PA. Considerable research has been done to refine methods for assessing PA, but relatively little attention has been given to operationalizing SB parameters (i.e., sedentary time and breaks from accelerometer data - particularly in relation to health outcomes. This study investigated: (a the accrued patterns of sedentary time and breaks; and (b the associations of sedentary time and breaks in different bout durations with cardiovascular risk factors.Accelerometer data on 5,917 adults from the National Health Examination and Nutrition Survey (NHANES 2003-2006 were used. Sedentary time and breaks at different bout durations (i.e., 1, 2-4, 5-9, 10-14, 15-19, 20-24, 25-29, and ≥ 30-min were obtained using a threshold of < 100 counts per minute. Sedentary time and breaks were regressed on cardiovascular risk factors (waist circumference, triglyceride, and high-density lipoprotein cholesterol and body mass index across bout durations.The results revealed that the majority of sedentary time occurred within relatively short bout durations (≈ 70% and ≈ 85% for < 5-min and < 10-min, respectively. The associations of sedentary time and breaks with health outcomes varied depending on how bout time was defined. Estimates of SB parameters based on bout durations of 5 min or shorter were associated with reduced cardiovascular risk factors while durations longer than 10-min were generally associated with increased risk factors.The present study demonstrates that the duration of sedentary bouts should be further considered when operationalizing the SB parameters from accelerometer data. The threshold of 5 minutes to define a bout is defensible, but a 10 minute threshold would provide a more conservative estimate to clearly capture the prolonged nature of sedentary behavior. Additional research is

  17. Sit-stand desks in call centres: associations of use and ergonomics awareness with sedentary behavior.

    Science.gov (United States)

    Straker, Leon; Abbott, Rebecca A; Heiden, Marina; Mathiassen, Svend Erik; Toomingas, Allan

    2013-07-01

    To investigate whether or not use of sit-stand desks and awareness of the importance of postural variation and breaks are associated with the pattern of sedentary behavior in office workers. The data came from a cross-sectional observation study of Swedish call centre workers. Inclinometers recorded 'seated' or 'standing/walking' episodes of 131 operators over a full work shift. Differences in sedentary behavior based on desk type and awareness of the importance of posture variation and breaks were assessed by non-parametric analyses. 90 (68.7%) operators worked at a sit-stand desk. Working at a sit-stand desk, as opposed to a sit desk, was associated with less time seated (78.5 vs 83.8%, p = 0.010), and less time taken to accumulate 5 min of standing/walking (36.2 vs 46.3 min, p = 0.022), but no significant difference to sitting episode length or the number of switches between sitting and standing/walking per hour. Ergonomics awareness was not associated with any sedentary pattern variable among those using a sit-stand desk. Use of sit-stand desks was associated with better sedentary behavior in call centre workers, however ergonomics awareness did not enhance the effect. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  18. Sedentary behavior in Dutch workers : Differences between occupations and business sectors

    NARCIS (Netherlands)

    Jans, M.P.; Proper, K.I.; Hildebrandt, V.H.

    2007-01-01

    Background: Sedentary behavior is an independent risk factor for excess body weight and other health problems. There are no published data on sitting time at work, or how this is related to occupation and sector (branch of business). No published study has shown whether extended sitting at work is

  19. Gender differences in physical activity, sedentary behavior, and their relation to body composition in active Brazilian adolescents.

    Science.gov (United States)

    Nogueira, Julia Aparecida Devide; Macedo da Costa, Teresa Helena

    2009-01-01

    Body weight and composition are determined by genotype, environment, and energy balance. Physical activity or sedentary behavior have different associations with body weight, fat mass, and fat-free mass, a relationship that is not clear in adolescents. The aim of this study was to test the associations between gender, physical activity, sedentary behavior, and body composition in physically active adolescents. Weight, height, and skinfold thickness were measured in 326 physically active boys and girls age 11 to 15 years. All subjects answered a questionnaire assessing their usual daily activities for the last month. Time spent on each activity was used to estimate the physical activity level (PAL). PAL was associated with body composition after adjustment for age and maturation, with differences between genders. For boys, PAL was positively and significantly associated with body mass index (BMI) and fat-free mass index (beta=0.14 and 0.15, respectively). For girls, PAL was negatively and significantly associated with BMI and fat mass index (beta=-0.11 and -0.75, respectively). Sedentary behavior, expressed by hours of TV, videogame, and computer use, was not associated with any body-composition outcome for either gender. The accumulated amount of physical activity, but not of sedentary behavior, was related to body composition in active adolescents.

  20. A Novel Physical Activity and Sedentary Behavior Classification and Its Relationship With Physical Fitness in Spanish Older Adults: The PHYSMED Study.

    Science.gov (United States)

    Aparicio-Ugarriza, Raquel; Pedrero-Chamizo, Raquel; Bibiloni, María Del Mar; Palacios, Gonzalo; Sureda, Antoni; Meléndez-Ortega, Agustín; Tur Marí, Josep Antoni; González-Gross, Marcela

    2017-10-01

    As there is no gold-standard methodology to classify older people in relation to physical activity (PA) and sedentary behavior (SB), this paper aimed to propose a classification combining PA and SB. Within a broader study, 433 subjects, aged 55 years and older (57% females) from Madrid and Majorca, were evaluated for PA and SB by means of validated questionnaires. Physical fitness was analyzed objectively using the EXERNET test battery. Cluster analyses were used to establish behavioral patterns, combining PA and SB. Males spent more time doing regular PA but less time walking and working at home than females (P sedentary, inactive and low sedentary, active and high sedentary, and active and low sedentary), the worst aerobic endurance (P active and low sedentary group (P work of public health authorities, researchers, and physicians.

  1. Break in Sedentary Behavior Reduces the Risk of Noncommunicable Diseases and Cardiometabolic Risk Factors among Workers in a Petroleum Company

    Directory of Open Access Journals (Sweden)

    Chutima Jalayondeja

    2017-05-01

    Full Text Available Although prolonged sitting appears as a novel risk factor related to health outcomes for all ages, its association needs to be replicated in occupational conditions. This study explored the associations between sedentary behavior and four noncommunicable diseases (NCDs as well as two cardiometabolic risk factors (CMRFs among workers in a petroleum company, Thailand. All workers were invited to complete the online self-report questionnaire. Sedentary behavior was measured as the amount of time sitting at work, during recreation, and while commuting. Out of 3365 workers contacted, 1133 (34% participated. Prevalence of NCDs and CMRFs was 36% and was positively associated with sedentary behavior. After adjusting for age, BMI, and exercise, the risk of NCDs and CMRFs for sedentary office work was 40% greater compared with more active field work. Those who took a break without sitting more than twice a day and commuted by walking or cycling had less risk of NCDs and CMRFs. The total duration of sedentary behavior was 10 h/day, and two-thirds of that total was workplace sitting. This was significantly associated with NCDs and CMRFs (p < 0.001. Day-and-night rotating shiftwork was negatively associated with NCDs and CMRFs (p < 0.001. Sedentary behavior should be considered a health risk among workers. Hence, to promote a healthy lifestyle and safe workplace, organizations should encourage standing activities during break and physically active commutes, and have workers avoid prolonged sitting.

  2. Liquid Phase Sintering of (Ti,Zr)C with WC-Co.

    Science.gov (United States)

    Ma, Taoran; Borrajo-Pelaez, Rafael; Hedström, Peter; Blomqvist, Andreas; Borgh, Ida; Norgren, Susanne; Odqvist, Joakim

    2017-01-11

    (Ti,Zr)C powder was sintered with WC-Co following an industrial process, including an isotherm at 1410 °C. A series of interrupted sintering trials was performed with the aim of studying the sintering behavior and the microstructural evolution during both solid-state and liquid-state sintering. Reference samples, using the same elemental compositions but with the starting components TiC and ZrC instead of (Ti,Zr)C, were also sintered. The microstructure was investigated using scanning electron microscopy and energy dispersive X-ray spectroscopy. It is found that the (Ti,Zr)C phase decomposes into Ti-rich and Zr-rich nano-scale lamellae before the liquid-state of the sintering initiates. The final microstructure consists of the binder and WC as well as two different γ phases, rich in either Ti (γ₁) or Zr (γ₂). The γ₂ phase grains have a core-shell structure with a (Ti,Zr)C core following the full sintering cycle. The major differences observed in (Ti,Zr)C with respect to the reference samples after the full sintering cycle were the referred core-shell structure and the carbide grain sizes; additionally, the microstructural evolution during sintering differs. The grain size of carbides (WC, γ₁, and γ₂) is about 10% smaller in WC-(Ti,Zr)C-Co than WC-TiC-ZrC-Co. The shrinkage behavior and hardness of both composites are reported and discussed.

  3. Liquid Phase Sintering of (Ti,ZrC with WC-Co

    Directory of Open Access Journals (Sweden)

    Taoran Ma

    2017-01-01

    Full Text Available (Ti,ZrC powder was sintered with WC-Co following an industrial process, including an isotherm at 1410 °C. A series of interrupted sintering trials was performed with the aim of studying the sintering behavior and the microstructural evolution during both solid-state and liquid-state sintering. Reference samples, using the same elemental compositions but with the starting components TiC and ZrC instead of (Ti,ZrC, were also sintered. The microstructure was investigated using scanning electron microscopy and energy dispersive X-ray spectroscopy. It is found that the (Ti,ZrC phase decomposes into Ti-rich and Zr-rich nano-scale lamellae before the liquid-state of the sintering initiates. The final microstructure consists of the binder and WC as well as two different γ phases, rich in either Ti (γ1 or Zr (γ2. The γ2 phase grains have a core-shell structure with a (Ti,ZrC core following the full sintering cycle. The major differences observed in (Ti,ZrC with respect to the reference samples after the full sintering cycle were the referred core-shell structure and the carbide grain sizes; additionally, the microstructural evolution during sintering differs. The grain size of carbides (WC, γ1, and γ2 is about 10% smaller in WC-(Ti,ZrC-Co than WC-TiC-ZrC-Co. The shrinkage behavior and hardness of both composites are reported and discussed.

  4. The Influence of Daily Stress on Sedentary Behavior: Group and Person (N of 1) Level Results of a 1-Year Observational Study.

    Science.gov (United States)

    Diaz, Keith M; Thanataveerat, Anusorn; Parsons, Faith E; Yoon, Sunmoo; Cheung, Ying Kuen; Alcantara, Carmela; Duran, Andrea T; Ensari, Ipek; Krupka, David J; Schwartz, Joseph E; Burg, Matthew M; Davidson, Karina W

    2018-05-24

    The purpose of this study, which used mobile technologies to continuously collect data over 1 year, was to examine the association of psychological stress with objectively measured sedentary behavior in adults at both the group (e.g. nomothetic approach) and individual (e.g. idiographic approach) level. Data were collected in an observational study of healthy adults (n=79) residing in the New York City metro area who were studied for 365 days from 2014-2015. Sedentary behavior was objectively measured via accelerometry. A smartphone-based electronic diary was used to assess level of stress ("Overall, how stressful was your day?"; 0-10 scale) and sources of stress. The end-of-day stress rating was not associated with total sedentary time (B= -1.34, p=0.767) at the group-level. When specific sources of stress were evaluated at the group-level, argument-related stress was associated with increased sedentariness; while running late- and work-related stress were associated with decreased sedentariness. There was a substantial degree of inter-individual variability in the relationship of stress with sedentary behavior. Both the level and sources of stress were associated with increased sedentariness for some, decreased sedentariness for others, and had no effect for many (within-person variance p-value stress on sedentary behavior varies by source of stress and from person-to-person. A precision medicine approach may be warranted to target reductions in sedentary time; although further studies are needed to confirm the observed findings in light of study limitations including a small sample size and enrollment of participants from a single, urban metropolitan area.

  5. Sedentary and physically active behavior patterns among low-income African-American and white adults living in the southeastern United States.

    Directory of Open Access Journals (Sweden)

    Sarah S Cohen

    Full Text Available Increased sedentary behavior and lack of physical activity are associated with increased risk for many chronic diseases. Differences in leisure-time physical activity between African American and white adults have been suggested to partially explain racial disparities in chronic disease outcomes, but expanding the definition of physical activity to include household and occupational activities may reduce or even eliminate racial differences in total physical activity. The objective of this study was to describe patterns of active and sedentary behaviors in black and white adults and to examine these behaviors across demographic measures. Sedentary and physically active behaviors were obtained from a validated physical activity questionnaire in 23,021 black men, 9,899 white men, 32,214 black women, and 15,425 white women (age 40-79 at enrollment into the Southern Community Cohort Study. Descriptive statistics for sedentary time; light, moderate, and vigorous household/occupational activity; sports/exercise; total activity; and meeting current physical activity recommendations via sports/exercise were examined for each race-sex group. Adjusted means were calculated using multiple linear regression models across demographic measures. Study participants spent approximately 60% of waking time in sedentary behaviors. Blacks reported more television viewing time than whites (45 minutes for females, 15 minutes for males, but when sitting time was expressed as a proportion of overall awake time, minimal racial differences were found. Patterns of light, moderate, and vigorous household/occupational activity were similar in all race/sex groups. 2008 Physical Activity Guidelines for Americans were followed by 16% of women and 25% of men independent of race. Overall, black and white men and women in this study spent the majority of their daily time in sedentary behaviors and less than one-fourth followed current guidelines for physical activity. These

  6. TRIBOLOGICAL PROPERTIES OF TiBx AND WC/C COATINGS

    Directory of Open Access Journals (Sweden)

    PETER KÚŠ

    2011-12-01

    Full Text Available Tribological properties of TiBx and WC/C coatings have been studied using the ball-on-disc method at room and elevated temperatures in air to investigate their behavior under conditions approaching high performance dry cutting. The average room temperature coefficients of friction (COF of both nanocomposite DC magnetron sputtered TiBx coatings and PECVD WC/C coatings were in the range 0.2-0.6. The lowest value of TiBx coatings of 0.16 was achieved in case of prefferentially oriented stuctures deposited at the highest negative bias. The lowest COF of WC/C was around 0.11. The increase of testing temperature to 450°C caused the increase of COF up to approximately 0.7-0.8. The experiments at elevated temperatures suggest the existence of the oxide transfer film with higher COF than that of the sliding contact without the film. Although both coating systems have relatively high COF values at elevated temperatures, they exhibit elements of some adaptive behavior.

  7. Association of Sedentary Behavior Time with Ideal Cardiovascular Health: The ORISCAV-LUX Study

    Science.gov (United States)

    Crichton, Georgina E.; Alkerwi, Ala'a

    2014-01-01

    Background Recently attention has been drawn to the health impacts of time spent engaging in sedentary behaviors. No studies have examined sedentary behaviors in relation to the newly defined construct of ideal cardiovascular health, which incorporates three health factors (blood pressure, total cholesterol, fasting plasma glucose) and four behaviors (physical activity, smoking, body mass index, diet). The purpose of this study was to examine associations between sedentary behaviors, including sitting time, and time spent viewing television and in front of a computer, with cardiovascular health, in a representative sample of adults from Luxembourg. Methods A cross-sectional analysis of 1262 participants in the Observation of Cardiovascular Risk Factors in Luxembourg study was conducted, who underwent objective cardiovascular health assessments and completed the International Physical Activity Questionnaire. A Cardiovascular Health Score was calculated based on the number of health factors and behaviors at ideal levels. Sitting time on a weekday, television time, and computer time (both on a workday and a day off), were related to the Cardiovascular Health Score. Results Higher weekday sitting time was significantly associated with a poorer Cardiovascular Health Score (p = 0.002 for linear trend), after full adjustment for age, gender, education, income and occupation. Television time was inversely associated with the Cardiovascular Health Score, on both a workday and a day off (p = 0.002 for both). A similar inverse relationship was observed between the Cardiovascular Health Score and computer time, only on a day off (p = 0.04). Conclusion Higher time spent sitting, viewing television, and using a computer during a day off may be unfavorably associated with ideal cardiovascular health. PMID:24925084

  8. Association of sedentary behavior time with ideal cardiovascular health: the ORISCAV-LUX study.

    Directory of Open Access Journals (Sweden)

    Georgina E Crichton

    Full Text Available Recently attention has been drawn to the health impacts of time spent engaging in sedentary behaviors. No studies have examined sedentary behaviors in relation to the newly defined construct of ideal cardiovascular health, which incorporates three health factors (blood pressure, total cholesterol, fasting plasma glucose and four behaviors (physical activity, smoking, body mass index, diet. The purpose of this study was to examine associations between sedentary behaviors, including sitting time, and time spent viewing television and in front of a computer, with cardiovascular health, in a representative sample of adults from Luxembourg.A cross-sectional analysis of 1262 participants in the Observation of Cardiovascular Risk Factors in Luxembourg study was conducted, who underwent objective cardiovascular health assessments and completed the International Physical Activity Questionnaire. A Cardiovascular Health Score was calculated based on the number of health factors and behaviors at ideal levels. Sitting time on a weekday, television time, and computer time (both on a workday and a day off, were related to the Cardiovascular Health Score.Higher weekday sitting time was significantly associated with a poorer Cardiovascular Health Score (p = 0.002 for linear trend, after full adjustment for age, gender, education, income and occupation. Television time was inversely associated with the Cardiovascular Health Score, on both a workday and a day off (p = 0.002 for both. A similar inverse relationship was observed between the Cardiovascular Health Score and computer time, only on a day off (p = 0.04.Higher time spent sitting, viewing television, and using a computer during a day off may be unfavorably associated with ideal cardiovascular health.

  9. Association of sedentary behavior time with ideal cardiovascular health: the ORISCAV-LUX study.

    Science.gov (United States)

    Crichton, Georgina E; Alkerwi, Ala'a

    2014-01-01

    Recently attention has been drawn to the health impacts of time spent engaging in sedentary behaviors. No studies have examined sedentary behaviors in relation to the newly defined construct of ideal cardiovascular health, which incorporates three health factors (blood pressure, total cholesterol, fasting plasma glucose) and four behaviors (physical activity, smoking, body mass index, diet). The purpose of this study was to examine associations between sedentary behaviors, including sitting time, and time spent viewing television and in front of a computer, with cardiovascular health, in a representative sample of adults from Luxembourg. A cross-sectional analysis of 1262 participants in the Observation of Cardiovascular Risk Factors in Luxembourg study was conducted, who underwent objective cardiovascular health assessments and completed the International Physical Activity Questionnaire. A Cardiovascular Health Score was calculated based on the number of health factors and behaviors at ideal levels. Sitting time on a weekday, television time, and computer time (both on a workday and a day off), were related to the Cardiovascular Health Score. Higher weekday sitting time was significantly associated with a poorer Cardiovascular Health Score (p = 0.002 for linear trend), after full adjustment for age, gender, education, income and occupation. Television time was inversely associated with the Cardiovascular Health Score, on both a workday and a day off (p = 0.002 for both). A similar inverse relationship was observed between the Cardiovascular Health Score and computer time, only on a day off (p = 0.04). Higher time spent sitting, viewing television, and using a computer during a day off may be unfavorably associated with ideal cardiovascular health.

  10. Physical activity, sedentary behaviors and dietary habits among Saudi adolescents relative to age, gender and region

    Directory of Open Access Journals (Sweden)

    Al-Hazzaa Hazzaa M

    2011-12-01

    Full Text Available Abstract Background Few lifestyle factors have been simultaneously studied and reported for Saudi adolescents. Therefore, the purpose of the present study was to report on the prevalence of physical activity, sedentary behaviors and dietary habits among Saudi adolescents and to examine the interrelationships among these factors using representative samples drawn from three major cities in Saudi Arabia. Methods This school-based cross-sectional study was conducted during the years 2009-2010 in three cities: Al-Khobar, Jeddah and Riyadh. The participants were 2908 secondary-school males (1401 and females (1507 aged 14-19 years, randomly selected using a multistage stratified sampling technique. Measurements included weight, height, sedentary behaviors (TV viewing, playing video games and computer use, physical activity using a validated questionnaire and dietary habits. Results A very high proportion (84% for males and 91.2% for females of Saudi adolescents spent more than 2 hours on screen time daily and almost half of the males and three-quarters of the females did not meet daily physical activity guidelines. The majority of adolescents did not have a daily intake of breakfast, fruit, vegetables and milk. Females were significantly (p p p p Conclusions The high prevalence of sedentary behaviors, physical inactivity and unhealthy dietary habits among Saudi adolescents is a major public health concern. There is an urgent need for national policy promoting active living and healthy eating and reducing sedentary behaviors among children and adolescents in Saudi Arabia.

  11. Sedentary behavior, physical activity, and psychological health of Korean older adults with hypertension: effect of an empowerment intervention.

    Science.gov (United States)

    Chang, Ae Kyung; Fritschi, Cynthia; Kim, Mi Ja

    2013-04-01

    The aim of this study was to determine the effect of an 8-week empowerment intervention on sedentary behavior, physical activity, and psychological health in Korean older adults with hypertension. Using a quasi-experimental design, older adults participated in either an experimental group (n = 27) or control group (n = 21). The experimental group received an empowerment intervention including lifestyle modification education, group discussion, and exercise training for 8 weeks, and the control group received standard hypertension education. After 8 weeks, participants in the experimental group had significantly decreased sedentary behavior, increased physical activity, increased self-efficacy for physical activity, and increased perceived health (p decreasing sedentary behavior and increasing physical activity, self-efficacy for physical activity, and perceived health in Korean older adults with hypertension. Copyright 2013, SLACK Incorporated.

  12. The measurement of sedentary patterns and behaviors using the activPAL™ Professional physical activity monitor

    International Nuclear Information System (INIS)

    Dowd, Kieran P; Bourke, Alan K; Nelson, John; Donnelly, Alan E; Harrington, Deirdre M

    2012-01-01

    Epidemiological studies have associated the negative effects of sedentary time and sedentary patterns on health indices. However, these studies have used methodologies that do not directly measure the sedentary state. Recent technological developments in the area of motion sensors have incorporated inclinometers, which can measure the inclination of the body directly, without relying on self-report or count thresholds. This paper aims to provide a detailed description of methodologies used to examine a range of relevant variables, including sedentary levels and patterns from an inclinometer-based motion sensor. The activPAL Professional physical activity logger provides an output which can be interpreted and used without the need for further processing and additional variables were derived using a custom designed MATLAB® computer program. The methodologies described have been implemented on a sample of 44 adolescent females, and the results of a range of daily physical activity and sedentary variables are described and presented. The results provide a range of objectively measured and objectively processed variables, including total time spent sitting/lying, standing and stepping, number and duration of daily sedentary bouts and both bed hours and non-bed hours, which may be of interest when making association between physical activity, sedentary behaviors and health indices. (paper)

  13. Do Sedentary Behaviors Modify the Health Status of Older Adults?

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    Elizabeth K. Lenz

    2014-01-01

    Full Text Available Evidence suggests sedentary behavior (SB negatively impacts the health of adults but less is known about SB impact on older adult (OA health.  Seventy OA (73.4±6years living in the southeast region of Wisconsin, United States of America (USA completed three SB diaries and had risk factors associated with cardiovascular disease (CVD assessed. Sedentary behaviors were quantified as time spent in sitting/lying activities. Pearson correlation coefficients, independent samples t-tests, and one-way ANOVA were performed to explore the relationship between SB and health. Older adults engaged in 620.3±91.2mins/d of SB with television watching (144.3±99.8mins/d being the most prominent. Total SB and television watching were correlated to multiple risk factors for CVD (r=-.241-.415, p=.009-.027 and these variables worsened as OA spent more time in those activities. Television watching was the only SB that increased across risk categories of CVD [F (2,67 =4.158, p=.020, eta squared=.11]. These results suggest SB, especially television watching to be related to risk factors of CVD in OA.

  14. Issues Related to Measuring and Interpreting Objectively Measured Sedentary Behavior Data

    Science.gov (United States)

    Janssen, Xanne; Cliff, Dylan P.

    2015-01-01

    The use of objective measures of sedentary behavior has increased over the past decade; however, as is the case for objectively measured physical activity, methodological decisions before and after data collection are likely to influence the outcomes. The aim of this article is to review the evidence on different methodological decisions made by…

  15. Cross-sectional surveillance study to phenotype lorry drivers’ sedentary behaviours, physical activity and cardio-metabolic health

    Science.gov (United States)

    Varela-Mato, Veronica; O’Shea, Orlagh; King, James A; Yates, Thomas; Stensel, David J; Biddle, Stuart JH; Nimmo, Myra A; Clemes, Stacy A

    2017-01-01

    Objectives Elevated risk factors for a number of chronic diseases have been identified in lorry drivers. Unhealthy lifestyle behaviours such as a lack of physical activity (PA) and high levels of sedentary behaviour (sitting) likely contribute to this elevated risk. This study behaviourally phenotyped UK lorry drivers’ sedentary and non-sedentary behaviours during workdays and non-workdays and examined markers of drivers cardio-metabolic health. Setting A transport company from the East Midlands, UK. Participants A sample of 159 male heavy goods vehicle drivers (91% white European; (median (range)) age: 50 (24, 67) years) completed the health assessments. 87 (age: 50.0 (25.0, 65.0); body mass index (BMI): 27.7 (19.6, 43.4) kg/m2) provided objective information on sedentary and non-sedentary time. Outcomes Participants self-reported their sociodemographic information. Primary outcomes: sedentary behaviour and PA, assessed over 7 days using an activPAL3 inclinometer. Cardio-metabolic markers included: blood pressure (BP), heart rate, waist circumference (WC), hip circumference, body composition and fasted capillary blood glucose, triglycerides, high-density lipopreotein cholesterol, low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) levels. These cardio-metabolic markers were treated as secondary outcomes. Results Lorry drivers presented an unhealthy cardio-metabolic health profile (median (IQR) systolic BP: 129 (108.5, 164) mm Hg; diastolic BP: 81 (63, 104) mm Hg; BMI: 29 (20, 47) kg/m2; WC: 102 (77.5, 146.5) cm; LDL-C: 3 (1, 6) mmol/L; TC: 4.9 (3, 7.5) mmol/L). 84% were overweight or obese, 43% had type 2 diabetes or prediabetes and 34% had the metabolic syndrome. The subsample of lorry drivers with objective postural data (n=87) accumulated 13 hours/day and 8 hours/day of sedentary behaviour on workdays and non-workdays (pdrivers accrued 12 min/day on workdays and 6 min/day on non-workdays of moderate-to-vigorous PA (MVPA). Conclusion

  16. School grade and sex differences in domain-specific sedentary behaviors among Japanese elementary school children: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Kaori Ishii

    2017-04-01

    Full Text Available Abstract Background It is vital to reduce the proportion of sedentary behavior in children. Understanding the duration and behavioral context is needed. The present study examined school-grade and sex differences in domain-specific sedentary times and concurrence with screen-time guidelines among Japanese elementary school children. Methods A total of 625 children (330 boys were surveyed in 2010 and 2014. Using a questionnaire, data regarding participants’ grade (first through third grades: lower grades; fourth through six grades: higher grades, sex, weight, and height were collected in addition to the time spent per day engaging in each specific sedentary behavior separately: (1 reading or listening to music, (2 TV or video viewing, (3 TV game use, (4 internet use excluding class, (5 homework, and (6 car travel. Two-way analysis of covariance and logistic regression analyses, adjusted for BMI and moderate to vigorous physical activity, were used to examine school-grade and sex differences in sedentary behaviors and the independent risk of exceeding recommended total daily screen time (< 2 h. Results On 625 children, mean minutes (SD of sedentary behavior per week in (1 – (6 were 90.3 (123.4, 535.0 (356.6, 167.3 (222.1, 23.9 (70.9, 264.9 (185.3, and 33.4 (61.2 in weekdays and 42.1 (70.0, 323.9 (232.0, 123.0 (96.4, 15.8 (49.9, 74.4 (96.4, and 71.3 (84.9 in weekends, respectively. There were differences in the minutes of sedentary behavior between participants of 2010 and 2014; e.g., TV game use and homework in weekdays and weekdays and car travel in weekends. Boys spent more time in TV game use, and girls spent more time reading, listening to music, doing homework, and car travel. Higher-grade students spent more time reading or listening to music, using a computer, and doing homework. Higher-grade students were 2.09 times (95% CI: 1.32 − 3.30 in whole week, 2.08 times (95% CI: 1.45 − 3.00 in weekday, and 1.88 times (95% CI: 1.29

  17. Fabrication and evaluation of atmospheric plasma spraying WC-Co-Cu-MoS2 composite coatings

    International Nuclear Information System (INIS)

    Yuan Jianhui; Zhu Yingchun; Zheng Xuebing; Ji Heng; Yang Tao

    2011-01-01

    Research highlights: → Protective WC-Co-based coatings containing solid lubricant Cu and MoS 2 used in wear applications were investigated in this study. → It was found that the MoS 2 composition in the feed powder was kept in WC-Co-Cu-MoS 2 coatings, and the decomposition and decarburization of WC in APS process were improved. → Combining the wear resistance of WC with the lubricating properties of Cu and MoS 2 has an extremely beneficial effect on improving the tribological performance of the resulting coating. - Abstract: Protective WC-Co-based coatings containing solid lubricant Cu and MoS 2 used in wear applications were investigated in this study. These coatings were deposited on mild steel substrates by atmospheric plasma spraying (APS). The feedstock powders were prepared by mechanically mixing the solid lubricant powders and WC-Co powder, followed by sintering and crushing the mixtures to avoid different particle flighting trajectories at plasma. The tribological properties of the coatings against stainless steel balls were examined by ball-on-disk (BOD) tribometer under normal atmospheric condition. The microstructure of the coatings was studied by optical microscope, scanning electron microscope and X-ray diffraction. It was found that the MoS 2 composition in the feed powder was kept in WC-Co-Cu-MoS 2 coatings, and the decomposition and decarburization of WC in APS process were improved, which were attributed to the protection of Cu around them. The friction and wear behaviors of all the WC-Co-Cu-MoS 2 coatings were superior to that of WC-Co coating. Such behavior was associated to different wear mechanisms operating for WC-Co coating and the WC-Co-Cu-MoS 2 coatings.

  18. Influence of sedentary behavior, physical activity, and cardiorespiratory fitness on the atherogenic index of plasma.

    Science.gov (United States)

    Edwards, Meghan K; Blaha, Michael J; Loprinzi, Paul D

    Atherogenic index of plasma (AIP), calculated as LOG 10 (triglycerides/high-density lipoprotein-cholesterol), may have greater utility over other metrics in predicting risk for cardiovascular disease (CVD). Previous work demonstrates the associations of physical activity (PA), sedentary behavior, and cardiorespiratory fitness (CRF) with triglycerides high-density lipoprotein (HDL-C) and CVD. Limited research has examined these parameters and their potential additive associations with AIP, which was the purpose of this study. Data from the 2003-2004 National Health and Nutrition Examination Survey (NHANES) were used (N = 307 adults 20-49 years). Sedentary behavior and moderate-to-vigorous physical activity (MVPA) were assessed via accelerometry. CRF was assessed via submaximal treadmill testing. Using median values, a PACS (Physical Activity Cardiorespiratory Sedentary) score (ranging from 0-3) was created, indicating the number of these positive characteristics (eg, above median CRF) each participant possessed. Above median MVPA was associated with significantly lower AIP values (β = -0.09; 95% CI, -0.17 to -0.01; P = .03), whereas above-median CRF (β = -0.0009; 95% CI, -0.09 to 0.08; P = .98) and below-median sedentary behavior (β = -0.02; 95% CI, -0.13 to 0.08; P = .60) were not. Compared to those with a PACS score of 0, those with a score of 1 or 2 did not have significantly reduced AIP values (β = 0.02; 95% CI, -0.06 to 0.10; P = .59, and β = 0.007; 95% CI, -0.12 to 0.13; P = .90, respectively); however, those with a score of 3 did (β = -0.14; 95% CI, -0.28 to -0.001; P = .04). Interventions targeting improvements in lipid profile (AIP) may wish to promote adequate MVPA over CRF or decreased sedentary behavior. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  19. Towards a Persuasive Mobile Application to Reduce Sedentary Behavior

    OpenAIRE

    Van Dantzig, S.; Geleijnse, G.; Van Halteren, A.T.

    2011-01-01

    Prolonged sitting is a potential health risk, not only for people with an inactive lifestyle, but also for those who do meet the recommended amount of physical activity. In this paper, we present two waysto promote the reduction of sedentary behavior. First, we report onan experiment in which office workers (n = 40) received timely persuasive messages on their smartphones, advising them to take an active break whenever 30 minutes of almost uninterrupted computer activity was recorded. The mes...

  20. Exposure to a community-wide campaign is associated with physical activity and sedentary behavior among Hispanic adults on the Texas-Mexico border.

    Science.gov (United States)

    Heredia, Natalia I; Lee, MinJae; Reininger, Belinda M

    2017-11-16

    Despite evidence for the use of community-wide campaigns to promote physical activity, few evaluations of community-wide campaigns in Hispanic communities exist. This study assessed the associations of exposure to a community-wide campaign with physical activity and sedentary behavior among Hispanic adults living on the Texas-Mexico border. The intervention, Tu Salud ¡Si Cuenta! (Your Health Matters!; TSSC), included a newsletter, community health worker discussion, TV and radio segments, which were conducted from 2005 to 2010. We matched an intervention (N = 399) and a control community (N = 400) on demographics and used a cross-sectional assessment in 2010 with randomly sampled adults from both communities. We collected exposure to the campaign, as well as physical activity and sedentary behavior with the International Physical Activity Questionnaire. We conducted bivariate analyses and multivariable logistic regression models to assess the association of TSSC exposure and its components with meeting moderate-to-vigorous intensity physical activity (MVPA) guidelines and exhibiting excessive sedentary behavior, controlling for covariates. As compared to the control community, the intervention community has 3 times the odds of meeting MVPA guidelines (Adjusted OR [AOR] = 3.01, 95% CI = 1.85-4.88, p sedentary behavior ((AOR = 0.46, 95% CI = 0.30-0.70, p sedentary behavior (AOR = 0.32, 95% CI 0.17-0.60, p sedentary behavior and higher odds of meeting MVPA guidelines. Exposure to radio segments was only associated with a significantly higher odds of meeting MVPA guidelines (AOR = 4.21, 95% CI = 1.17-15.09). This study provides some evidence of the association of community-wide campaigns and its components in Hispanic communities with higher levels of MVPA and lower levels of excessive sedentary behavior. NCT00788879 Date: November 11, 2008.

  1. Effects of WC Particle Size and Co Content on the Graded Structure in Functionally Gradient WC-Co Composites

    Directory of Open Access Journals (Sweden)

    Yuan Yigao

    2016-01-01

    Full Text Available Functionally gradient WC-Co composites having a Co depleted surface zone and not comprising the h phase can be manufactured via carburizing process. During carburizing, besides carburizing process parameters, the microstructural parameters of WC-Co materials, such as WC grain size and Co content, also have significant influences on the formation of Co gradient structure. In this study, the effects of WC particle size and Co content on the gradient structure within gradient hardmetals have been studied, based on a series of carburizing experiments of WC-Co materials with different WC particle sizes and cobalt contents. The results show that both the thickness and the amplitude of the gradients within gradient WC-Co materials increase with increasing initial WC particle size and Co content of WC-Co alloys. The reason for this finding is discussed.

  2. A review of early influences on physical activity and sedentary behaviors of preschool-age children in high-income countries.

    Science.gov (United States)

    Lindsay, Ana Cristina; Greaney, Mary L; Wallington, Sherrie F; Mesa, Tatiana; Salas, Carlos F

    2017-07-01

    Promoting physical activity (PA) is a key component of preventing and controlling childhood obesity. Despite well-documented benefits of PA, globally, rates of PA among young children have declined over the past decades, and most children are not accruing sufficient PA daily. Helping children develop the foundation for PA habits early in life is critical for the promotion of health in childhood and prevention of chronic diseases later in life, and will ultimately promote longer and healthier lives for individuals and the general population. The purpose of this review is to provide a synthesis of current evidence on influences on PA and sedentary behaviors of preschool-age children in high-income countries. A systematic review of three databases was performed. Studies conducted in high-income countries and published from 2000 onward that addressed influences on PA and sedentary behaviors of preschool-age children were identified and reviewed. Additionally, reference lists of identified articles and relevant published reviews were reviewed. Studies that met the following inclusion criteria were considered: (a) sample included preschoolers (age ≤5 years); (b) PA and/or sedentary behaviors or factors associated with PA and/or sedentary behaviors was assessed; (c) published in English; (d) used either quantitative or qualitative methods; and (e) conducted in a high-income country. Data were extracted from selected studies to identify influences on PA and sedentary behaviors of preschool-age children and organized using the social-ecological model according to multiple levels of influence. Results from included studies identify multiple factors that influence PA and sedentary behaviors of young children in high-income countries at the various levels of the social-ecological model including intrapersonal, interpersonal, environmental, organizational, and policy. Given pediatric nurses' role as primary care providers, and their frequent and continued contact with parents

  3. Validation of the Actigraph GT3X and ActivPAL Accelerometers for the Assessment of Sedentary Behavior

    Science.gov (United States)

    Kim, Youngdeok; Barry, Vaughn W.; Kang, Minsoo

    2015-01-01

    This study examined (a) the validity of two accelerometers (ActiGraph GT3X [ActiGraph LLC, Pensacola, FL, USA] and activPAL [PAL Technologies Ltd., Glasgow, Scotland]) for the assessment of sedentary behavior; and (b) the variations in assessment accuracy by setting minimum sedentary bout durations against a proxy for direct observation using an…

  4. National youth sedentary behavior and physical activity daily patterns using latent class analysis applied to accelerometry.

    Science.gov (United States)

    Evenson, Kelly R; Wen, Fang; Hales, Derek; Herring, Amy H

    2016-05-03

    Applying latent class analysis (LCA) to accelerometry can help elucidated underlying patterns. This study described the patterns of accelerometer-determined sedentary behavior and physical activity among youth by applying LCA to a nationally representative United States (US) sample. Using 2003-2006 National Health and Nutrition Examination Survey data, 3998 youths 6-17 years wore an ActiGraph 7164 accelerometer for one week, providing > =3 days of wear for > =8 h/day from 6:00 am-midnight. Cutpoints defined sedentary behavior ( = 2296 counts/minute), and vigorous activity (> = 4012 counts/minute). To account for wear time differences, outcomes were expressed as percent of day in a given intensity. LCA was used to classify daily (Monday through Sunday) patterns of average counts/minute, sedentary behavior, light activity, MVPA, and vigorous activity separately. The latent classes were explored overall and by age (6-11, 12-14, 15-17 years), gender, and whether or not youth attended school during measurement. Estimates were weighted to account for the sampling frame. For average counts/minute/day, four classes emerged from least to most active: 40.9% of population (mean 323.5 counts/minute/day), 40.3% (559.6 counts/minute/day), 16.5% (810.0 counts/minute/day), and 2.3% (1132.9 counts/minute/day). For percent of sedentary behavior, four classes emerged: 13.5% of population (mean 544.6 min/day), 30.1% (455.1 min/day), 38.5% (357.7 min/day), and 18.0% (259.2 min/day). For percent of light activity, four classes emerged: 12.3% of population (mean 222.6 min/day), 29.3% (301.7 min/day), 41.8% (384.0 min/day), and 16.6% (455.5 min/day). For percent of MVPA, four classes emerged: 59.9% of population (mean 25.0 min/day), 33.3% (60.9 min/day), 3.1% (89.0 min/day), and 3.6% (109.3 min/day). For percent of vigorous activity, three classes emerged: 76.8% of population (mean 7.1 min/day), 18.5% (23.9 min/day), and 4.7% (47.4 min/day). Classes were developed by age

  5. Health-related quality of life, physical activity, and sedentary behavior of adults with visual impairments.

    Science.gov (United States)

    Haegele, Justin A; Famelia, Ruri; Lee, Jihyun

    2017-11-01

    Research suggests that physical activity and sedentary behaviors can impact one's health-related quality of life (HRQoL). However, little is known about the impact that these behaviors can have on the HRQoL of those with visual impairments. Therefore, the primary purpose of this study was to determine the associations of physical activity and sedentary behavior with HRQoL among a sample of adults with visual impairments. Individuals with visual impairments were invited via email to complete three questionnaires: (a) the international physical activity questionnaire-short form, (b) the Rasch-revised versions of the World Health Organization Quality of Life instrument with the Level of Independence subscale, and (c) a demographic questionnaire. Eighty participants (M age   =   47.5) provided usable surveys for analyses. The results demonstrated that physical activity significantly predicted HRQoL (F(2,79) = 3.508, p = .035, R 2 Adjusted =.060), yet, sedentary behavior did not (F(2,79) = 1.546, p = .220, R 2  = .039, R 2 Adjusted =.014). Gender differences were uncovered regarding the relationship between physical activity and health-related quality of life. The findings of this study demonstrate the importance of physical activity in influencing the HRQoL of adults with visual impairments. This study supports the need for additional intervention research to promote physical activity for those with visual impairments. Implications for Rehabilitations Adults with visual impairments tend to report lower health-related quality of life than peers without visual impairments. Regular participation in leisure-time physical activity, and restricted sedentary time, have been demonstrated to positively influence health-related quality of life for adults without disabilities. In this study, physical activity shows promise as an effective means of improving health-related quality of life for adults with visual impairments.

  6. Cross-sectional and longitudinal associations of different sedentary behaviors with cognitive performance in older adults.

    Directory of Open Access Journals (Sweden)

    Emmanuelle Kesse-Guyot

    Full Text Available The deleterious health effects of sedentary behaviors, independent of physical activity, are increasingly being recognized. However, associations with cognitive performance are not known.To estimate the associations between different sedentary behaviors and cognitive performance in healthy older adults.Computer use, time spent watching television (TV, time spent reading and habitual physical activity levels were self-reported twice (in 2001 and 2007 by participants in the SUpplémentation en Vitamines et MinérauX (SU.VI.MAX and SU.VI.MAX2 study. Cognitive performance was assessed at follow-up (in 2007-2009 via a battery of 6 neuropsychological tests used to derive verbal memory and executive functioning scores. Analyses (ANCOVA were performed among 1425 men and 1154 women aged 65.6 ± 4.5 at the time of the neuropsychological evaluation. We estimated mean differences with 95% confidence intervals (95%CI in cognitive performance across categories of each type of sedentary behavior.In multivariable cross-sectional models, compared to non-users, participants using the computer for >1 h/day displayed better verbal memory (mean difference=1.86; 95%CI: 0.95, 2.77 and executive functioning (mean difference=2.15; 95%CI: 1.22, 3.08. A negative association was also observed between TV viewing and executive functioning. Additionally, participants who increased their computer use by more than 30 min between 2001 and 2007 showed better performance on both verbal memory (mean difference=1.41; 95%CI: 0.55, 2.27 and executive functioning (mean difference=1.41; 95%CI: 0.53, 2.28 compared to those who decreased their computer use during that period.Specific sedentary behaviors are differentially associated with cognitive performance. In contrast to TV viewing, regular computer use may help maintain cognitive function during the aging process.clinicaltrial.gov (number NCT00272428.

  7. Evaluation of a questionnaire to assess sedentary and active behaviors in the Southern Community Cohort Study.

    Science.gov (United States)

    Buchowski, Maciej S; Matthews, Charles E; Cohen, Sarah S; Signorello, Lisa B; Fowke, Jay H; Hargreaves, Margaret K; Schlundt, David G; Blot, William J

    2012-08-01

    Low physical activity (PA) is linked to cancer and other diseases prevalent in racial/ethnic minorities and low-income populations. This study evaluated the PA questionnaire (PAQ) used in the Southern Cohort Community Study, a prospective investigation of health disparities between African-American and white adults. The PAQ was administered upon entry into the cohort (PAQ1) and after 12-15 months (PAQ2) in 118 participants (40-60 year-old, 48% male, 74% African-American). Test-retest reliability (PAQ1 versus PAQ2) was assessed using Spearman correlations and the Wilcoxon signed rank test. Criterion validity of the PAQ was assessed via comparison with a PA monitor and a last-month PA survey (LMPAS), administered up to 4 times in the study period. The PAQ test-retest reliability ranged from 0.25-0.54 for sedentary behaviors and 0.22-0.47 for active behaviors. The criterion validity for the PAQ compared with PA monitor ranged from 0.21-0.24 for sedentary behaviors and from 0.17-0.31 for active behaviors. There was general consistency in the magnitude of correlations between the PAQ and PA-monitor between African-Americans and whites. The SCCS-PAQ has fair to moderate test-retest reliability and demonstrated some evidence of criterion validity for ranking participants by their level of sedentary and active behaviors.

  8. Sedentary Behavior Is Independently Related to Fat Mass among Children and Adolescents in South China

    OpenAIRE

    Xue, Hongmei; Tian, Guo; Duan, Ruonan; Quan, Liming; Zhao, Li; Yang, Min; Libuda, Lars; Muckelbauer, Rebecca; Cheng, Guo

    2016-01-01

    We aim to explore the independent associations of sedentary behaviors (SB) with body mass distribution among Chinese children. Data on the screen-based sedentary time (television viewing and computer use) and doing homework, physical activities and dietary intake of 1586 Chinese children (50.3% girls) aged 7–15 years were obtained through validated questionnaires. Skin-fold thickness, body height, and weight were measured to calculate percent body fat (%BF), fat mass index (FMI), and fat-free...

  9. Associations of sedentary behavior and physical activity with physical measurements and dyslipidemia in school-age children: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Wei Zheng

    2016-11-01

    Full Text Available Abstract Background Physical activity and sedentary behavior are common factors influencing cardiovascular health. However, how school and leisure-time activity/sedentary behavior are associated with physical fitness and blood lipid levels in primary school children in consideration of gender disparity remains unclear. Methods Data was obtained from a health and nutrition survey on primary school children from nine areas in China. The association between physical activities/sedentary behaviors (school and leisure-time physical activity levels, screen time, and other sedentary behaviors and anthropometric measurements/prevalence of dyslipidemia were examined by multilevel analysis (the individual level, class level, grade level, and investigation area level adjusted for age, energy intake and family income. Results A total of 770 participants (average age = 9.4 ± 1.7 years were included. Prevalence of dyslipidemia was 10.9%. Prevalence of dyslipidemia was associated with screen time in boys [OR = 3.04, 95% CI (1.24–7.45] and inversely associated with leisure-time physical activity in boys [OR = 2.22, 95% CI (1.08–4.56] and school-time activity in girls [OR = 5.34, 95% CI (1.18–24.16]. Conclusions Physical activity—but not sedentary behavior—was significantly associated with dyslipidemia in both genders. Increasing leisure-time physical activity for boys and school-time physical activity for girls may be critical.

  10. Physical activity, sedentary behaviors and the incidence of type 2 diabetes mellitus: the Multi-Ethnic Study of Atherosclerosis (MESA)

    OpenAIRE

    Joseph, Joshua J; Echouffo-Tcheugui, Justin B; Golden, Sherita H; Chen, Haiying; Jenny, Nancy Swords; Carnethon, Mercedes R; Jacobs, David; Burke, Gregory L; Vaidya, Dhananjay; Ouyang, Pamela; Bertoni, Alain G

    2016-01-01

    Background: The association between physical activity (PA), sedentary behavior, and incident diabetes has been assessed in whites but is less well investigated in multiethnic populations. Objective: To assess the association between PA, sedentary behavior, and incident diabetes in the Multi-Ethnic Study of Atherosclerosis. Research design and methods Incident diabetes was assessed among adults without prevalent baseline diabetes (2000–2002) at 5 in-person examinations between 2002 and 2012. B...

  11. Factors Associated with Physical Activity and Sedentary Behavior in Older Adults from Six Low- and Middle-Income Countries

    Directory of Open Access Journals (Sweden)

    Cadeyrn J. Gaskin

    2018-05-01

    Full Text Available Rising life expectancy in low- and middle-income countries (LMIC, coupled with the increasing burden of non-communicable diseases, accentuates the importance of generating information to support public health strategies. With this aim in mind, the purpose of this study was to identify correlates of physical activity and sedentary behavior in LMIC. We analyzed Wave 1 data (collected 2007–2010 from the World Health Organization’s longitudinal Study on global AGEing and adult health (SAGE, which focuses on nationally representative samples of adults aged 50 years and older from six countries (China, n = 13,157; India, n = 6560; Mexico, n = 2301; Russian Federation, n = 3763; South Africa, n = 3836; and Ghana, n = 4305. Associations of physical activity (operationalized as meeting physical activity guidelines of ≥150 min/week of moderate-to-vigorous physical activity or not and sedentary behavior (≥4 h/day versus <4 h/day with demographic, health and health risk, functional, interpersonal, and environmental factors were assessed using multivariate logistic models. Across the six countries, we found fairly consistent and reasonably strong associations between both physical activity and sedentary behavior and several demographic factors (age and employment, in particular, self-reported health, instrumental activities of daily living, factors relating to socializing, and household location. Correlates of physical activity and sedentary behavior in LMIC appear to be similar to those found in high-income countries.

  12. Do sedentary behaviors mediate associations between socio-demographic characteristics and BMI in women living in socio-economically disadvantaged neighborhoods?

    Science.gov (United States)

    Compernolle, Sofie; De Cocker, Katrien; Abbott, Gavin; Verloigne, Maïté; Cardon, Greet; De Bourdeaudhuij, Ilse; Ball, Kylie

    2015-04-09

    Women living in deprived neighborhoods are a risk group for overweight and obesity, particularly during the childbearing years. Several socio-demographic characteristics may compound this risk, but little is known about why this might be the case. Sedentary behaviors are emerging as a socio-demographically patterned risk factor for obesity. The purpose of the present study was to assess socio-demographic differences in sedentary behaviors, and to examine whether these behaviors could explain the relation between socio-demographic variables and BMI (BMI) in this risk group. Women aged 18-46 years were recruited from 40 urban and 40 rural deprived neighborhoods in Victoria, Australia. In total, 3879 women reported socio-demographic variables (age, educational level, employment status, marital status, number of children, residential location and country of birth), sedentary behaviors (television time, computer time, total screen time and total sedentary time), physical activity, and height and weight, which were used to calculate BMI. For each socio-demographic variable, four single mediation models were conducted using two-level mixed-models regression analyses. Mediating effects were examined using the MacKinnon product-of-coefficients procedure and the Sobel test. All socio-demographic variables were significantly associated with sedentary behaviors. Single mediation analyses revealed that television time (αβ = 0.017, 95% CI = 0.000, 0.030) and total screen time (αβ = 0.006, 95% CI = 0.000, 0.012) mediated 14.1% and 4.9% of the relationship between educational level and BMI, respectively. Total screen time mediated 45.1% of the relationship between employment status and BMI (αβ = -0.020, 95% CI = -0.033, -0.006), and television time mediated 8.2% of the relationship between country of birth and BMI (αβ = -0.008, 95% CI = -0.016, -0.001). Sedentary behaviors differed depending on socio-demographic characteristics, and partly

  13. Obesity and Other Correlates of Physical Activity and Sedentary Behaviors among US High School Students

    Directory of Open Access Journals (Sweden)

    Richard Lowry

    2013-01-01

    Full Text Available Understanding correlates of physical activity (PA can help inform and improve programs that promote PA among youth. We analyzed data from the 2010 National Youth Physical Activity and Nutrition Study, a representative sample of US students in grades 9–12. Logistic regression was used to examine associations between PA correlates (obesity, physical education classes, sports team participation, attitude toward PA, adult support for PA, and environmental support for PA and participation in daily PA (DPA, vigorous PA (VPA, muscle-strengthening activity (MSA, viewing television (TV, and using computers or video games (C/VG. A positive attitude toward PA and adult support for PA were both associated with increased PA and decreased sedentary behavior. However, among students who lived in neighborhoods that were not safe for PA, a positive attitude toward PA was not associated with increased DPA or decreased sedentary behavior and was less strongly associated with VPA and MSA. Efforts to increase PA among youth should promote a positive attitude toward PA among youth and encourage adult family members to support their efforts to be active. Policies that promote safe neighborhoods may work synergistically with a positive attitude toward PA to increase participation in PA and decrease sedentary behaviors.

  14. Level of Sedentary Behavior and Its Associated Factors among Saudi Women Working in Office-Based Jobs in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Nada M. Albawardi

    2017-06-01

    Full Text Available Research in Saudi Arabia has revealed a shocking level of insufficiently physically active adults, particularly women. The risk of sedentary behavior will likely increase as the number of women with office-based jobs increases. The aim of this study is to determine the level of sedentary behavior, and its associated factors, among Saudi women working office-based jobs in the city of Riyadh. A cross-sectional study of 420 Saudi female employees at 8 office-based worksites were measured to determine body mass index and were given a self-administered survey to evaluate their level of physical activity and sedentary behavior. Median sitting time on work days was 690 min per day (interquartile range, IQR 541–870, with nearly half accumulated during work hours, and 575 min per day (IQR 360–780 on non-work days. Predictors of work day sitting time were level of education, number of children, and working in the private sector. Number of children, whether they were single, and whether they lived in a small home were found to predict non-work day sitting time. This study identifies Saudi women in office-based jobs as a high-risk group for sedentary behavior. There is a need to promote physical activity at worksites and reduce prolonged sitting.

  15. Level of Sedentary Behavior and Its Associated Factors among Saudi Women Working in Office-Based Jobs in Saudi Arabia.

    Science.gov (United States)

    Albawardi, Nada M; Jradi, Hoda; Almalki, Abdulla A; Al-Hazzaa, Hazzaa M

    2017-06-19

    Research in Saudi Arabia has revealed a shocking level of insufficiently physically active adults, particularly women. The risk of sedentary behavior will likely increase as the number of women with office-based jobs increases. The aim of this study is to determine the level of sedentary behavior, and its associated factors, among Saudi women working office-based jobs in the city of Riyadh. A cross-sectional study of 420 Saudi female employees at 8 office-based worksites were measured to determine body mass index and were given a self-administered survey to evaluate their level of physical activity and sedentary behavior. Median sitting time on work days was 690 min per day (interquartile range, IQR 541-870), with nearly half accumulated during work hours, and 575 min per day (IQR 360-780) on non-work days. Predictors of work day sitting time were level of education, number of children, and working in the private sector. Number of children, whether they were single, and whether they lived in a small home were found to predict non-work day sitting time. This study identifies Saudi women in office-based jobs as a high-risk group for sedentary behavior. There is a need to promote physical activity at worksites and reduce prolonged sitting.

  16. The Association between Dry Eye Disease and Physical Activity as well as Sedentary Behavior: Results from the Osaka Study.

    Science.gov (United States)

    Kawashima, Motoko; Uchino, Miki; Yokoi, Norihiko; Uchino, Yuichi; Dogru, Murat; Komuro, Aoi; Sonomura, Yukiko; Kato, Hiroaki; Nishiwaki, Yuji; Kinoshita, Shigeru; Tsubota, Kazuo

    2014-01-01

    Purpose. To assess the association of dry eye disease (DED) with physical activity and sedentary behavior. Methods. The cross-sectional survey conducted included Japanese office workers who use visual display terminals (n = 672). DED was assessed according to the Japanese Dry Eye Diagnostic Criteria, and participants were categorized into "definite DED," "probable DED," or "non-DED" groups based on the results of DED examinations. Physical activity and sedentary behavior of participants were assessed using the International Physical Activity Questionnaire (IPAQ), and physical activity level was calculated in metabolic equivalent units per week (MET, min/week). Participants were classified as having a high, moderate, or low level of physical activity. Results. Participants with abnormal tear break-up time (BUT) (≤5 s) were involved in sedentary behavior for significantly longer duration than those with normal BUT (P = 0.035). Non-DED participants (14.5%) tended to have higher levels of physical activity than definite DED participants (2.5%). Participants with definite DED had significantly lower MET scores than those with non-DED (P = 0.025). Conclusions. Our findings suggest that a lower level of physical activity and sedentary behavior are associated with DED; however, longitudinal/intervention studies with large groups of participants are needed to validate these findings.

  17. Effects of a DVD-delivered exercise program on patterns of sedentary behavior in older adults: a randomized controlled trial.

    Science.gov (United States)

    Fanning, J; Porter, G; Awick, E A; Wójcicki, T R; Gothe, N P; Roberts, S A; Ehlers, D K; Motl, R W; McAuley, E

    2016-06-01

    In the present study, we examined the influence of a home-based, DVD-delivered exercise intervention on daily sedentary time and breaks in sedentary time in older adults. Between 2010 and 2012, older adults (i.e., aged 65 or older) residing in Illinois (N = 307) were randomized into a 6-month home-based, DVD-delivered exercise program (i.e., FlexToBa; FTB) or a waitlist control. Participants completed measurements prior to the first week (baseline), following the intervention period (month 6), and after a 6 month no-contact follow-up (month 12). Sedentary behavior was measured objectively using accelerometers for 7 consecutive days at each time point. Differences in daily sedentary time and breaks between groups and across the three time points were examined using mixed-factor analysis of variance (mixed ANOVA) and analysis of covariance (ANCOVA). Mixed ANOVA models revealed that daily minutes of sedentary time did not differ by group or time. The FTB condition, however, demonstrated a greater number of daily breaks in sedentary time relative to the control condition (p = .02). ANCOVA models revealed a non-significant effect favoring FTB at month 6, and a significant difference between groups at month 12 (p = .02). While overall sedentary time did not differ between groups, the DVD-delivered exercise intervention was effective for maintaining a greater number of breaks when compared with the control condition. Given the accumulating evidence emphasizing the importance of breaking up sedentary time, these findings have important implications for the design of future health behavior interventions.

  18. Impact of a Mobile Phone Intervention to Reduce Sedentary Behavior in a Community Sample of Adults: A Quasi-Experimental Evaluation.

    Science.gov (United States)

    Kendzor, Darla E; Shuval, Kerem; Gabriel, Kelley Pettee; Businelle, Michael S; Ma, Ping; High, Robin R; Cuate, Erica L; Poonawalla, Insiya B; Rios, Debra M; Demark-Wahnefried, Wendy; Swartz, Michael D; Wetter, David W

    2016-01-25

    Greater time spent sedentary is linked with increased risk of breast, colorectal, ovarian, endometrial, and prostate cancers. Given steadily increasing rates of mobile phone ownership, mobile phone interventions may have the potential to broadly influence sedentary behavior across settings. The purpose of this study was to examine the short-term impact of a mobile phone intervention that targeted sedentary time in a diverse community sample. Adults participated in a quasi-experimental evaluation of a mobile phone intervention designed to reduce sedentary time through prompts to interrupt periods of sitting. Participants carried mobile phones and wore accelerometers for 7 consecutive days. Intervention participants additionally received mobile phone prompts during self-reported sitting and information about the negative health impact of prolonged sedentariness. The study was conducted from December 2012 to November 2013 in Dallas, Texas. Linear mixed model regression analyses were conducted to evaluate the influence of the intervention on daily accelerometer-determined estimates of sedentary and active time. Participants (N=215) were predominantly female (67.9%, 146/215) and nonwhite (black: 50.7%, 109/215; Latino: 12.1%, 26/215; other: 5.6%, 12/215). Analyses revealed that participants who received the mobile phone intervention had significantly fewer daily minutes of sedentary time (B=-22.09, P=.045) and more daily active minutes (B=23.01, P=.04) than control participants. A simple mobile phone intervention was associated with engaging in less sedentary time and more physical activity. Findings underscore the potential impact of mobile phone interventions to positively influence sedentary behavior and physical activity.

  19. Cross-sectional surveillance study to phenotype lorry drivers' sedentary behaviours, physical activity and cardio-metabolic health.

    Science.gov (United States)

    Varela-Mato, Veronica; O'Shea, Orlagh; King, James A; Yates, Thomas; Stensel, David J; Biddle, Stuart Jh; Nimmo, Myra A; Clemes, Stacy A

    2017-06-21

    Elevated risk factors for a number of chronic diseases have been identified in lorry drivers. Unhealthy lifestyle behaviours such as a lack of physical activity (PA) and high levels of sedentary behaviour (sitting) likely contribute to this elevated risk. This study behaviourally phenotyped UK lorry drivers' sedentary and non-sedentary behaviours during workdays and non-workdays and examined markers of drivers cardio-metabolic health. A transport company from the East Midlands, UK. A sample of 159 male heavy goods vehicle drivers (91% white European; (median (range)) age: 50 (24, 67) years) completed the health assessments. 87 (age: 50.0 (25.0, 65.0); body mass index (BMI): 27.7 (19.6, 43.4) kg/m 2 ) provided objective information on sedentary and non-sedentary time. Participants self-reported their sociodemographic information. Primary outcomes: sedentary behaviour and PA, assessed over 7 days using an activPAL3 inclinometer. Cardio-metabolic markers included: blood pressure (BP), heart rate, waist circumference (WC), hip circumference, body composition and fasted capillary blood glucose, triglycerides, high-density lipopreotein cholesterol, low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) levels. These cardio-metabolic markers were treated as secondary outcomes. Lorry drivers presented an unhealthy cardio-metabolic health profile (median (IQR) systolic BP: 129 (108.5, 164) mm Hg; diastolic BP: 81 (63, 104) mm Hg; BMI: 29 (20, 47) kg/m 2 ; WC: 102 (77.5, 146.5) cm; LDL-C: 3 (1, 6) mmol/L; TC: 4.9 (3, 7.5) mmol/L). 84% were overweight or obese, 43% had type 2 diabetes or prediabetes and 34% had the metabolic syndrome. The subsample of lorry drivers with objective postural data (n=87) accumulated 13 hours/day and 8 hours/day of sedentary behaviour on workdays and non-workdays (pdrivers accrued 12 min/day on workdays and 6 min/day on non-workdays of moderate-to-vigorous PA (MVPA). Lorry drivers demonstrate a high-risk cardio

  20. Measurement of Sedentary Behaviors or "Downtime" in Rett Syndrome

    DEFF Research Database (Denmark)

    Stahlhut, Michelle; Hill, Kylie; Bisgaard, Anne-Marie

    2017-01-01

    measured duration of sedentary time with a mean difference (limit of agreement) of -1.0 (6.3) minutes. The duration of Bouchard activity record downtime accounted for 73% of the variance of sedentary time measured by the activPAL (coefficient 0.762, 95% CI 0.413 to 1.111). These data provide clinicians......This study aimed to validate measures of sedentary time in individuals with Rett syndrome. Twenty-six individuals (median [IQR] age 16.0 (9.4-20.6) years) wore an activPAL accelerometer during video-taped activities and agreement was determined between sedentary time determined by the activ......PAL and observation. For 11 individuals (median [IQR] age 14.5 (11.5-25.6) years), linear regression was used to determine the relationship between sedentary time recorded on the modified Bouchard activity record diary card and measured using the activPAL. In comparison to observation, the activPAL accurately...

  1. On the preparation of fine V8C7-WC and V4C3-WC powders

    CSIR Research Space (South Africa)

    Osborne, C

    1997-01-01

    Full Text Available The aim of this work was to produce V8C7-WC and V4C3-WC powders with grain size between 1 and 2mu-m, as a first stage of the preparation of fine grained WC-VC-Co hardmetal. V8C7-WC powder was produced via two routes: starting from preformed V8C7...

  2. Clustering of dietary intake and sedentary behavior in 2-year-old children.

    Science.gov (United States)

    Gubbels, Jessica S; Kremers, Stef P J; Stafleu, Annette; Dagnelie, Pieter C; de Vries, Sanne I; de Vries, Nanne K; Thijs, Carel

    2009-08-01

    To examine clustering of energy balance-related behaviors (EBRBs) in young children. This is crucial because lifestyle habits are formed at an early age and track in later life. This study is the first to examine EBRB clustering in children as young as 2 years. Cross-sectional data originated from the Child, Parent and Health: Lifestyle and Genetic Constitution (KOALA) Birth Cohort Study. Parents of 2578 2-year-old children completed a questionnaire. Correlation analyses, principal component analyses, and linear regression analyses were performed to examine clustering of EBRBs. We found modest but consistent correlations in EBRBs. Two clusters emerged: a "sedentary-snacking cluster" and a "fiber cluster." Television viewing clustered with computer use and unhealthy dietary behaviors. Children who frequently consumed vegetables also consumed fruit and brown bread more often and white bread less often. Lower maternal education and maternal obesity were associated with high scores on the sedentary-snacking cluster, whereas higher educational level was associated with high fiber cluster scores. Obesity-prone behavioral clusters are already visible in 2-year-old children and are related to maternal characteristics. The findings suggest that obesity prevention should apply an integrated approach to physical activity and dietary intake in early childhood.

  3. The Association between Dry Eye Disease and Physical Activity as well as Sedentary Behavior: Results from the Osaka Study

    OpenAIRE

    Kawashima, Motoko; Uchino, Miki; Yokoi, Norihiko; Uchino, Yuichi; Dogru, Murat; Komuro, Aoi; Sonomura, Yukiko; Kato, Hiroaki; Nishiwaki, Yuji; Kinoshita, Shigeru; Tsubota, Kazuo

    2014-01-01

    Purpose. To assess the association of dry eye disease (DED) with physical activity and sedentary behavior. Methods. The cross-sectional survey conducted included Japanese office workers who use visual display terminals (n = 672). DED was assessed according to the Japanese Dry Eye Diagnostic Criteria, and participants were categorized into “definite DED,” “probable DED,” or “non-DED” groups based on the results of DED examinations. Physical activity and sedentary behavior of participants were ...

  4. Behavioral response to a just-in-time adaptive intervention (JITAI) to reduce sedentary behavior in obese adults: Implications for JITAI optimization.

    Science.gov (United States)

    Thomas, J Graham; Bond, Dale S

    2015-12-01

    Just-in-time adaptive interventions (JITAIs) use mobile computers, sensors, and software analytics to automatically detect behavior and deliver tailored treatment. However, little is known about how JITAIs influence patterns of behavior or how best to design JITAIs for maximum effect. This study examined prompts and behavioral response to the B-MOBILE JITAI for reducing sedentary behavior (SB) in overweight/obese individuals. Thirty participants (83% women; 67% White, mean ± SD body mass index = 36.2 kg/m2) tested 3 conditions presented in a randomized counterbalanced order involving smartphone-based prompts for walking breaks of (a) 3 min after 30 SB min, (b) 6 min after 60 SB min, and (c) 12 min after 120 SB min. Participants carried the smartphone an average of 6.90 days during each 7-day condition, for an average of 14.94 hr per day. The 3- and 6-min conditions resulted in the greatest number of prompts, walking breaks, the best adherence to prompts, the greatest amount of daily time spent in walking breaks, and fastest adherence to prompts (ps < .01). Small but statistically significant decreases in the number of daily walking breaks, adherence to prompts, and minutes per day spent in walking breaks were observed as a function of the number of days spent in a condition (ps < .05). The B-MOBILE JITAI was effective in prompting breaks in sedentary behavior when it was most clinically relevant. Frequent prompts for small change may be an optimal strategy for shaping sedentary behavior, although more research is needed to determine how best to promote long-term adherence. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  5. The Association of Dietary Behaviors and Physical Activity Levels with General and Central Obesity among ASEAN University Students

    Directory of Open Access Journals (Sweden)

    Karl Peltzer

    2017-06-01

    Full Text Available Objective: To quantify the prevalence of obesity and obesity-related factors (dietary behaviors and physical activity levels in a cross-sectional, observational study of ASEAN undergraduate students. Material and Methods: A total of 6783 (35.5% male and 64.5% female undergraduate students (Mean age: 20.5, SD = 2.0 from eight ASEAN countries completed questionnaires and anthropometric measurements. Multivariable logistic regression was used to estimate odds ratios (ORs for the association of nutrition behaviors with prevalence of general obesity (body mass index ≥ 25 kg/m², elevated waist-to-height ratio (WHtR (>0.50, and high waist circumference (WC (≥80 cm in females, ≥90 cm in males. Covariates included sociodemographic factors, dietary behavior, physical activity and sitting time (using the “International Physical Activity Questionnaire”. Results: There was a higher prevalence of general obesity (24.2% versus 9.3%, and high WHtR (16.6% versus 12.1 in males relative to females, while high WC (9.4% versus 10.4% did not significantly differ between genders. In multivariable logistic regression analyses, compared to females, males had higher odds of obesity (odds-ratio, OR: 2.13, confidence interval, CI: 1.80, 2.77, and high WHtR (OR: 1.90, CI: 1.48, 2.43 (P < 0.001 for both. Snacking frequency and avoiding fatty foods were associated with all three obesity indicators; obesity (OR: 1.16, CI: 1.05, 1.28 and OR: 1.54, CI: 1.24, 1.92, respectively, WHtR (OR: 1.17, CI: 1.04, 1.32 and OR: 1.46, CI: 1.04, 1.54, and high WC (OR: 1.16, CI: 2.01, 1.33 and OR 1.52, CI: 1.14, 2.04, respectively. Physical activity and sedentary behavior were not significantly associated with any obesity measure. Conclusions: There was a low prevalence of healthy behaviors and a high prevalence of obesity in this sample of ASEAN young adults. Specific dietary behaviors but not physical activity nor sedentary behavior were associated with obesity.

  6. Physical activity in different periods of life, sedentary behavior, and the risk of ovarian cancer in the NIH-AARP diet and health study.

    Science.gov (United States)

    Xiao, Qian; Yang, Hannah P; Wentzensen, Nicolas; Hollenbeck, Albert; Matthews, Charles E

    2013-11-01

    Physical activity and sedentary behavior may influence ovarian cancer risk, but clear evidence is lacking. We prospectively investigated the relations of self-reported physical activity and sedentary behavior to ovarian cancer incidence in a cohort of 148,892 U.S. women ages 50-71 years at baseline (1995-1996), who were followed through 2006. Multivariate Cox proportional hazard models were used to estimate relative risks (RR) and 95% confidence intervals (CI). We also conducted analysis by hormone use, body mass index (BMI), and cancer subtype. We identified 753 incident epithelial ovarian cancers. Overall, neither physical activity nor sedentary behavior at baseline was associated with ovarian cancer risk. Compared with women who never or rarely engaged in vigorous physical activity in the past year, women who reported more than 5 times/week of vigorous physical activity had an RR of 1.05 (95% CI, 0.84-1.32). Women who sat 7+ hours/day had an RR of 1.05 (95% CI, 0.80-1.37) compared with those reporting sedentary behavior in middle and older ages were not associated with ovarian cancer risk. We found no clear support for a role of physical activity and sedentary behavior in ovarian cancer risk. ©2013 AACR.

  7. Low Levels of Physical Activity and Sedentary Behavior in Adults with Intellectual Disabilities

    Directory of Open Access Journals (Sweden)

    Kelly Hsieh

    2017-12-01

    Full Text Available Adults with intellectual disabilities (ID are more likely to lead sedentary lifestyles and have low levels of physical activity (LLPA. The present study investigated the prevalence of reported LLPA and time spent watching TV in adults with ID and identified the associated factors for these behaviors. The proxy informants of 1618 adults with ID completed the surveys regarding their health behaviors. Multiple logistic regressions were employed for LLPA and multiple linear regressions for time spent watching TV. About 60% of adults with ID had LLPA and average time spent watching TV was 3.4 h a day. Some characteristics and health and function variables were identified as associated factors. While engaging in community activities and involvement in Special Olympics were inversely associated with LLPA, they were not associated with time spent watching TV. Attending day/educational programs or being employed were associated with spending less time watching TV. Findings highlight differential factors associated with LLPA versus TV-watching behavior in adults with ID. Hence, a key strategy aimed at increasing physical activity includes promoting participation in social and community activities, while targeted activities for reducing sedentary behavior might focus on providing day programs or employment opportunities for adults with ID.

  8. The Association between Dry Eye Disease and Physical Activity as well as Sedentary Behavior: Results from the Osaka Study

    Directory of Open Access Journals (Sweden)

    Motoko Kawashima

    2014-01-01

    Full Text Available Purpose. To assess the association of dry eye disease (DED with physical activity and sedentary behavior. Methods. The cross-sectional survey conducted included Japanese office workers who use visual display terminals (n=672. DED was assessed according to the Japanese Dry Eye Diagnostic Criteria, and participants were categorized into “definite DED,” “probable DED,” or “non-DED” groups based on the results of DED examinations. Physical activity and sedentary behavior of participants were assessed using the International Physical Activity Questionnaire (IPAQ, and physical activity level was calculated in metabolic equivalent units per week (MET, min/week. Participants were classified as having a high, moderate, or low level of physical activity. Results. Participants with abnormal tear break-up time (BUT (≤5 s were involved in sedentary behavior for significantly longer duration than those with normal BUT (P=0.035. Non-DED participants (14.5% tended to have higher levels of physical activity than definite DED participants (2.5%. Participants with definite DED had significantly lower MET scores than those with non-DED (P=0.025. Conclusions. Our findings suggest that a lower level of physical activity and sedentary behavior are associated with DED; however, longitudinal/intervention studies with large groups of participants are needed to validate these findings.

  9. Examination of perceived neighborhood characteristics and transportation on changes in physical activity and sedentary behavior: The Trial of Activity in Adolescent Girls.

    Science.gov (United States)

    Evenson, Kelly R; Murray, David M; Birnbaum, Amanda S; Cohen, Deborah A

    2010-09-01

    We examined the association between perceived neighborhood characteristics and transport and 2-year changes in accelerometer-determined nonschool MET-weighted moderate-to-vigorous physical activity (MW-MVPA) and sedentary behavior of adolescent girls. Reporting that children do not play outdoors in their neighborhood, that their neighborhood was well lit, and that there were trails in their neighborhood were each associated with significant decreases in nonschool MW-MVPA. None of the neighborhood or transportation measures was associated with changes in nonschool sedentary behavior. Further work is needed to understand the determinants of the decline in physical activity and the increase in sedentary behavior among adolescent girls. Copyright 2010 Elsevier Ltd. All rights reserved.

  10. The Role of Physical Activity and Sedentary Behaviors in Explaining the Association Between Acculturation and Obesity Among Mexican-American Adults.

    Science.gov (United States)

    Murillo, Rosenda; Albrecht, Sandra S; Daviglus, Martha L; Kershaw, Kiarri N

    2015-01-01

    We investigated associations of acculturation with various types of activity (moderate-vigorous leisure-time physical activity [LTPA], moderate-vigorous work- and transportation-related physical activity, and sedentary activity), and whether these activities mediated the acculturation-obesity association among Mexican-Americans. Cross-sectional. National Health and Nutrition Examination Survey (NHANES) 2007-2010. Mexican-American NHANES participants aged ≥20 years (n = 1902). Demographic characteristics, physical activity, sedentary behavior, acculturation, and body mass index. Multinomial logistic regression was used to estimate associations of acculturation with categories of self-reported activity. Path analysis was used to test whether the activity measures mediated acculturation-obesity associations. In adjusted models, compared to U.S.-born Mexican-Americans, foreign-born Mexican-Americans living in the United States for less than 10 years were significantly less likely to be in the highest LTPA and sedentary activity categories, and more likely to be in the highest total and transportation activity categories. Foreign-born Mexican-Americans living in the United States for 10 years or more were significantly less likely to engage in high sedentary activity but more likely to engage in high transportation activity. Sedentary behavior was the strongest mediator of the acculturation-obesity association, accounting for 40.7% and 57.1% of the total effect of acculturation on obesity among foreign-born Mexican-Americans living in the United States for less than 10 years and for 10 years or more, respectively, compared to U.S.-born Mexican-Americans. Reducing sedentary behavior may lower the negative impact of acculturation on obesity.

  11. Relationship between children's physical activity, sedentary behavior, and childcare environments: A cross sectional study

    Directory of Open Access Journals (Sweden)

    Michele E. Peden

    2017-06-01

    This study extends previous research by identifying differences between toddlers and preschooler's physical activity and sedentary behaviors in relation to childcare environments. A greater understanding of how the childcare environment relates to sitting time for both toddlers and preschool aged children is needed.

  12. Physical Activity, Sedentary Behavior, and Diet-Related eHealth and mHealth Research: Bibliometric Analysis.

    Science.gov (United States)

    Müller, Andre Matthias; Maher, Carol A; Vandelanotte, Corneel; Hingle, Melanie; Middelweerd, Anouk; Lopez, Michael L; DeSmet, Ann; Short, Camille E; Nathan, Nicole; Hutchesson, Melinda J; Poppe, Louise; Woods, Catherine B; Williams, Susan L; Wark, Petra A

    2018-04-18

    Electronic health (eHealth) and mobile health (mHealth) approaches to address low physical activity levels, sedentary behavior, and unhealthy diets have received significant research attention. However, attempts to systematically map the entirety of the research field are lacking. This gap can be filled with a bibliometric study, where publication-specific data such as citations, journals, authors, and keywords are used to provide a systematic overview of a specific field. Such analyses will help researchers better position their work. The objective of this review was to use bibliometric data to provide an overview of the eHealth and mHealth research field related to physical activity, sedentary behavior, and diet. The Web of Science (WoS) Core Collection was searched to retrieve all existing and highly cited (as defined by WoS) physical activity, sedentary behavior, and diet related eHealth and mHealth research papers published in English between January 1, 2000 and December 31, 2016. Retrieved titles were screened for eligibility, using the abstract and full-text where needed. We described publication trends over time, which included journals, authors, and countries of eligible papers, as well as their keywords and subject categories. Citations of eligible papers were compared with those expected based on published data. Additionally, we described highly-cited papers of the field (ie, top ranked 1%). The search identified 4805 hits, of which 1712 (including 42 highly-cited papers) were included in the analyses. Publication output increased on an average of 26% per year since 2000, with 49.00% (839/1712) of papers being published between 2014 and 2016. Overall and throughout the years, eHealth and mHealth papers related to physical activity, sedentary behavior, and diet received more citations than expected compared with papers in the same WoS subject categories. The Journal of Medical Internet Research published most papers in the field (9.58%, 164/1712). Most

  13. Improvement in tribological properties of atmospheric plasma-sprayed WC-Co coating followed by Cu electrochemical impregnation

    International Nuclear Information System (INIS)

    Yuan Jianhui; Zhu Yingchun; Zheng Xuebing; Ruan Qichao; Ji Heng

    2009-01-01

    The WC-Co coating obtained by atmospheric plasma spraying (APS) was modified by Cu electrochemical impregnation. The copper has infiltrated into and filled up the pores in WC-Co coating. The tribological properties of the coating against the stainless steel ball as sliding pairs were investigated with a ball-on-disc (BOD) configuration in air at room temperature. The as-prepared samples were characterized by means of optical microscope, scanning electron microscope and X-ray diffraction. It was found that the frictional behavior of the WC-Co coating followed by Cu electrochemical impregnation was superior to that of WC-Co coating. The wear mechanism of the WC-Co coating followed by Cu electrochemical impregnation was microcutting, whilst that of a WC-Co coating was the fatigue wear. The improvement in tribological properties of the WC-Co coating followed by Cu electrochemical impregnation was attributed to the formation of self-lubricating Cu film on the wear surface which induces the transformation of wear mechanism.

  14. [Association of physical activities, sedentary behaviors with overweight/obesity in 9-11 year-old Chinese primary school students].

    Science.gov (United States)

    Chen, L; Li, Q; Song, Y; Ma, J; Wang, H J

    2016-06-18

    To explore the association of physical activities, sedentary behaviors with overweight/obesity in Chinese children aged 9-11 years, analyze the gender difference and heterogeneity of the association across different provinces, and provide evidence for prevention and control of overweight and obesity. Using the data of 40 692 children aged 9-11 years from Chinese National Survey on Students' Constitution and Health in 2010, the height and weight were measured and the time spent in physical activities, screen behaviors and homework were collected. We analyzed the associations among physical activities, sedentary behaviors and overweight/obesity in boys and girls separately, and assessed the heterogeneity of associations across different provinces with Meta-analysis. The prevalence of overweight/obesity of the boys (27.1%) was higher than that of the girls (12.9%), compared with the rural students (15.6%), the situation of overweight/obesity of the urban students (23.8%) was more serious, the prevalences of overweight/obesity were separately 22.6%, 19.2% and 17.5% among developed, middle-developed and undeveloped social economic status subgroups. The boys with physical activities no more than 1 hour per day were more likely to be overweight/obese, with the OR of 1.09 (95%CI: 1.02, 1.17). The girls with screen time more than 1 hour per day or homework time more than 2 hours per day were more likely to be overweight/obese, with the ORs of 1.13 (95%CI: 1.02, 1.26) and 1.18 (95%CI: 1.03, 1.35) respectively. The high level of sedentary behaviors (more than 135 min per day) was associated with overweight/obese in the girls, and the OR was 1.19 (95%CI: 1.08, 1.33). There was no significant heterogeneity of effect values between physical activities and overweight/obesity in the boys and between sedentary behaviors and overweight/obesity in the girls across the different provinces (P> 0.05). The associations among physical activities, sedentary behaviors and overweight

  15. Measuring older adults' sedentary time: reliability, validity, and responsiveness.

    Science.gov (United States)

    Gardiner, Paul A; Clark, Bronwyn K; Healy, Genevieve N; Eakin, Elizabeth G; Winkler, Elisabeth A H; Owen, Neville

    2011-11-01

    With evidence that prolonged sitting has deleterious health consequences, decreasing sedentary time is a potentially important preventive health target. High-quality measures, particularly for use with older adults, who are the most sedentary population group, are needed to evaluate the effect of sedentary behavior interventions. We examined the reliability, validity, and responsiveness to change of a self-report sedentary behavior questionnaire that assessed time spent in behaviors common among older adults: watching television, computer use, reading, socializing, transport and hobbies, and a summary measure (total sedentary time). In the context of a sedentary behavior intervention, nonworking older adults (n = 48, age = 73 ± 8 yr (mean ± SD)) completed the questionnaire on three occasions during a 2-wk period (7 d between administrations) and wore an accelerometer (ActiGraph model GT1M) for two periods of 6 d. Test-retest reliability (for the individual items and the summary measure) and validity (self-reported total sedentary time compared with accelerometer-derived sedentary time) were assessed during the 1-wk preintervention period, using Spearman (ρ) correlations and 95% confidence intervals (CI). Responsiveness to change after the intervention was assessed using the responsiveness statistic (RS). Test-retest reliability was excellent for television viewing time (ρ (95% CI) = 0.78 (0.63-0.89)), computer use (ρ (95% CI) = 0.90 (0.83-0.94)), and reading (ρ (95% CI) = 0.77 (0.62-0.86)); acceptable for hobbies (ρ (95% CI) = 0.61 (0.39-0.76)); and poor for socializing and transport (ρ < 0.45). Total sedentary time had acceptable test-retest reliability (ρ (95% CI) = 0.52 (0.27-0.70)) and validity (ρ (95% CI) = 0.30 (0.02-0.54)). Self-report total sedentary time was similarly responsive to change (RS = 0.47) as accelerometer-derived sedentary time (RS = 0.39). The summary measure of total sedentary time has good repeatability and modest validity and is

  16. Self-monitoring of spontaneous physical activity and sedentary behavior to prevent weight regain in older adults.

    Science.gov (United States)

    Nicklas, Barbara J; Gaukstern, Jill E; Beavers, Kristen M; Newman, Jill C; Leng, Xiaoyan; Rejeski, W Jack

    2014-06-01

    The objective was to determine whether adding a self-regulatory intervention (SRI) focused on self-monitoring of spontaneous physical activity (SPA) and sedentary behavior to a standard weight loss intervention improved maintenance of lost weight. Older (65-79 years), obese (BMI = 30-40 kg/m(2) ) adults (n = 48) were randomized to a 5-month weight loss intervention involving a hypocaloric diet (DIET) and aerobic exercise (EX) with or without the SRI to promote SPA and decrease sedentary behavior (SRI + DIET + EX compared with DIET + EX). Following the weight loss phase, both groups transitioned to self-selected diet and exercise behavior during a 5-month follow-up. Throughout the 10-months, the SRI + DIET + EX group utilized real-time accelerometer feedback for self-monitoring. There was an overall group by time effect of the SRI (P DIET + EX lost less weight and regained more weight than SRI + DIET + EX. The average weight regain during follow-up was 1.3 kg less in the SRI + DIET + EX group. Individuals in this group maintained approximately 10% lower weight than baseline compared with those in the DIET + EX group whom maintained approximately 5% lower weight than baseline. Addition of a SRI, designed to increase SPA and decrease sedentary behavior, to a standard weight loss intervention enhanced successful maintenance of lost weight. Copyright © 2014 The Obesity Society.

  17. Erosion resistance of FeAl-TiB2 and FeAl-WC at room and elevated temperatures

    International Nuclear Information System (INIS)

    Alman, D.E.; Tylczak, J.H.; Hawk, J.A.

    2000-01-01

    The resistance of FeAl-40%TiB 2 and FeAl-80%WC cermets to solid particle erosion at 25, 180, 500 and 700 C was evaluated and compared to the behavior of WC-6%Co (Co-90%WC) cemented carbides. Even though the WC-Co contained a higher volume fraction of the hard phase, the erosion rates of the FeAl-cermets were similar in magnitude to the erosion rates of the WC-Co. However, the erosion rates of the FeAl-cermets either were constant (FeAl-TiB 2 ) or decreased (FeAl-WC) with increasing test temperature; whereas, the erosion rates of the WC-Co cemented carbides increased with increasing test temperature. This indicated that once the microstructures of the FeAl-cermets are optimized for wear resistance, these materials might make promising candidates for high-temperature wear applications

  18. BeWell24: development and process evaluation of a smartphone "app" to improve sleep, sedentary, and active behaviors in US Veterans with increased metabolic risk.

    Science.gov (United States)

    Buman, Matthew P; Epstein, Dana R; Gutierrez, Monica; Herb, Christine; Hollingshead, Kevin; Huberty, Jennifer L; Hekler, Eric B; Vega-López, Sonia; Ohri-Vachaspati, Punam; Hekler, Andrea C; Baldwin, Carol M

    2016-09-01

    Lifestyle behaviors across the 24-h spectrum (i.e., sleep, sedentary, and active behaviors) drive metabolic risk. We describe the development and process evaluation of BeWell24, a multicomponent smartphone application (or "app") that targets behavior change in these interdependent behaviors. A community-embedded iterative design framework was used to develop the app. An 8-week multiphase optimization strategy design study was used to test the initial efficacy of the sleep, sedentary, and exercise components of the app. Process evaluation outcomes included objectively measured app usage statistics (e.g., minutes of usage, self-monitoring patterns), user experience interviews, and satisfaction ratings. Participants (N = 26) logged approximately 60 % of their sleep, sedentary, and exercise behaviors, which took 3-4 min/day to complete. Usage of the sleep and sedentary components peaked at week 2 and remained high throughout the intervention. Exercise component use was low. User experiences were mixed, and overall satisfaction was modest.

  19. Completion report for the isolation and remediation of inactive liquid low-level radioactive waste tanks WC-5, WC-6, WC-8, WC-19, 3002-A, 7560, and 7562 at Oak Ridge National Laboratory Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1997-12-01

    The Federal Facility Agreement (FFA) between the U.S. Environmental Protection Agency (EPA), Tennessee Department of Environment and Conservation (TDEC), and U.S. Department of Energy (DOE) requires that all liquid low-level waste tanks at Oak Ridge National Laboratory removed from service, designated in the FFA as Category D, be remediated in accordance with Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) requirements. A human health risk screening assessment was conducted for inactive Tanks WC-5, WC-6, WC-8, WC-19, 3002-A, 7560, and 7562 as part of an evaluation to determine the method of remediation necessary to safely and permanently isolate and remediate the tanks. Risk screening assessment results indicated that the health risks associated with these tanks were within or below the EPA range of concern of 1 x 10 -4 to 1 x 10 -6 . On the basis of these results and with regulators concurrence, it was determined that either no action or in-place stabilization of the tanks would satisfy risk-based remediation goals. Therefore, decisions were made and approved by DOE to remediate these tanks in-place as maintenance actions rather than actions under the CERCLA process. Letters documenting these decisions were approved by DOE and subsequently submitted to TDEC and EPA, who concurred with the maintenance actions. Tanks WC-5, WC-6, WC-8, WC-19, 3002-A, 7560, and 7562 were isolated from associated piping, electrical systems, and instrumentation and were grouted in-place. Tank 7562 was originally isolated from associated piping and instrumentation and left in-place empty for future remedial consideration. Upon further consideration, the decision was made by DOE, with concurrence by the regulators, to complete the maintenance action of Tank 7562 by grouting it in-place in March 1997

  20. High sedentary behavior and compromised physical capabilities in adult smokers despite the suitable level of physical activity in daily life

    Directory of Open Access Journals (Sweden)

    Vinicius Tonon Lauria

    2017-05-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2017v19n1p62   Sedentary behavior may play an important role for health outcomes, regardless of the amount of physical activity in daily life (PADL.We aimed to evaluate and compare sedentary behavior as well as physical capabilities in physically active smokers and non-smokers. Twenty-eight adult smokers and 38 non-smokers free of lung disease were matched for age, sex, body mass index, body composition, cardiovascular risk and moderate-to-vigorous PADL. Participants underwent spirometry, cardiopulmonary exercise test (CPET, six-minute walk test (6MWT, isokinetic dynamometry, and body composition (bioelectrical impedance.Despite the similar amount of moderate-to-vigorous PADL(median, 4.5h/week for smokers and 4.0h/week for non-smokers, smokers spent more time lying (median, 8.2h/week: 95% confidence interval, 5.4 to 19.1 vs. 6.1h/week: 3.7 to 11.2 and in sedentary activities (median, 100h/week: 66 to 129 vs. 78h/week: 55 to 122 compared to non-smokers. Smokers also presented worse spirometry, peak V’O2 and maximum heart rate in the CPET, 6MWT, and isokinetic indices (p<0.05. We observed a strong correlation between the time spent lying and spirometry (r = - 0.730 in smokers. Smoking is related to higher sedentary behavior, despite the suitable PADL. An appropriate PADL did not reduce the deleterious effects of smoking on physical capabilities. Interrupting sedentary behavior may be an appropriate intervention target in smokers for reducing the risk of diseases.

  1. Moderate-to-vigorous physical activity as a mediator between sedentary behavior and cardiometabolic risk in Spanish healthy adults: a mediation analysis

    OpenAIRE

    García-Hermoso, Antonio; Martínez-Vizcaíno, Vicente; Sánchez-López, Mairena; Recio-Rodriguez, Jose I.; Gómez-Marcos, Manuel A.; García-Ortiz, Luis

    2015-01-01

    Background Public health strategies for cardiovascular prevention highlight the importance of physical activity, but do not consider the additional potentially harmful effects of sedentary behavior. This study was conducted between 2010 and 2012 and analyzed between 2013 and 2014. The aim of the study was to analyze the relationship between sedentary behavior and cardiometabolic risk factors in the Spanish adult population and to examine whether this relationship is mediated by moderate-to-vi...

  2. Crime rates and sedentary behavior among 4th grade Texas school children

    Directory of Open Access Journals (Sweden)

    Hoelscher Deanna M

    2008-05-01

    Full Text Available Abstract Introduction Although per capita crime has generally fallen over the period which coincides with the obesity epidemic, it has not fallen uniformly across communities. It also has not fallen enough to allay fears on the part of parents. Over the past 30 years, technological changes have made the indoor alternatives to playing outside, where children are more vulnerable to criminal activity, more enjoyable (cable TV, video games, and the internet and comfortable (the spread of air conditioning to low income neighborhoods. We determined whether indoor sedentary behavior patterns are associated with community crime statistics. 4th graders in the U.S. are typically 9 or 10 years old. Methods We used data from the 2004–2005 Texas School Physical Activity and Nutrition (SPAN survey linked with U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics data for the years 2000 through 2005 and Texas State data on sexual offenders. The probability-based sample included a total of 7,907 children in grade four. Multistage probability sampling weights were used. The dependent variables included were hours of TV watching, video game playing, computer use and total indoor sedentary behavior after school. Incremental Relative Rates were computed for community crime rates including robberies, all violent crimes, murders, assaults, property crimes, rapes, burglaries, larcenies and motor vehicle thefts as well as for sexual offenders living in the neighborhood. The neighborhood refers to the areas where the students at each school live. In the case of sexual offenders, sexual offenders per capita are estimated using the per capita rate in the zip code of the school attended; all other crime statistics are estimated by the crimes per capita in the police department jurisdiction covering the school attended. After controlling for sex, age, and African-American and Hispanic, cross-sectional associations were determined using

  3. Parent dietary, physical activity and sedentary behaviors associated with child behaviors and weight status among private school children in Delhi, India: A cross-sectional study

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    Blanche Greene-Cramer

    2016-01-01

    Full Text Available Background Family can be an important socializing agent that strongly influences child and adolescent behavior. While studies have found associations between parent modeling of healthy behaviors and these behaviors in children in the US and other western countries, there is a dearth of research examining these associations among low and middle-income countries like India. This study examines the association between parent dietary, physical activity, and sedentary behaviors and child behaviors and weight status in Delhi, India. Methods The study was cross-sectional by design. The target population was comprised of a convenience sample of 6th and 8th grade children enrolled at 6 private schools in Delhi, India and their parents. A total of 551 child-parent dyads were used in analysis. Measures included parent and child BMI; physical activity and sedentary behavior; and dietary intake, such as weekly breakfast consumption, daily fruit and vegetable (FV consumption, daily low-fat dairy consumption, daily energy-dense (ED food consumption, daily sugar-sweetened beverage (SSB consumption. Mixed-effects linear regression models were used to test for the association between parent dietary, physical activity, and sedentary behaviors (independent variables and child dietary, physical activity and sedentary behaviors (dependent variables while controlling for parent and child demographics. Results Significant, positive associations were observed between all parent and child dietary behaviors (weekly breakfast consumption, daily FV consumption, daily low-fat dairy consumption, daily ED food consumption, daily SSB consumption after adjusting for child sex and grade, parent sex, and parent weight status (p<0.05, all. Parent moderate/vigorous physical activity was positively associated with child moderate/vigorous physical activity (p=0.000, however there was no significant association between parent and child light physical activity levels (p=0.310. Parent

  4. Exposure to a community-wide campaign is associated with physical activity and sedentary behavior among Hispanic adults on the Texas-Mexico border

    Directory of Open Access Journals (Sweden)

    Natalia I. Heredia

    2017-11-01

    Full Text Available Abstract Background Despite evidence for the use of community-wide campaigns to promote physical activity, few evaluations of community–wide campaigns in Hispanic communities exist. This study assessed the associations of exposure to a community-wide campaign with physical activity and sedentary behavior among Hispanic adults living on the Texas-Mexico border. Methods The intervention, Tu Salud ¡Si Cuenta! (Your Health Matters!; TSSC, included a newsletter, community health worker discussion, TV and radio segments, which were conducted from 2005 to 2010. We matched an intervention (N = 399 and a control community (N = 400 on demographics and used a cross-sectional assessment in 2010 with randomly sampled adults from both communities. We collected exposure to the campaign, as well as physical activity and sedentary behavior with the International Physical Activity Questionnaire. We conducted bivariate analyses and multivariable logistic regression models to assess the association of TSSC exposure and its components with meeting moderate-to-vigorous intensity physical activity (MVPA guidelines and exhibiting excessive sedentary behavior, controlling for covariates. Results As compared to the control community, the intervention community has 3 times the odds of meeting MVPA guidelines (Adjusted OR [AOR] = 3.01, 95% CI = 1.85–4.88, p < .05 and 2 times lower odds of excessive sedentary behavior ((AOR = 0.46, 95% CI = 0.30–0.70, p < .05. Exposure in the intervention group to any component was associated with five times the odds of meeting MVPA guidelines (AOR = 5.10, 95% CI 2.88–9.03, p < .001 and 3 times lower odds of excessive sedentary behavior (AOR = 0.32, 95% CI 0.17–0.60, p < .001, compared with those unexposed in the control community. Exposure to newsletters, CHW discussions and TV segments were associated with significantly lower odds of excessive sedentary behavior and higher odds of

  5. Trends in physical activity, sedentary behavior, diet, and BMI among US adolescents, 2001-2009.

    Science.gov (United States)

    Iannotti, Ronald J; Wang, Jing

    2013-10-01

    The high prevalence of adolescent obesity in the United States has been attributed to population changes in physical activity (PA), sedentary behaviors, and dietary behaviors. This study examines 8-year trends in these behaviors in US adolescents ages 11 to 16. Nationally representative samples of US students in grades 6 to 10 were recruited during the 2001-2002 (N = 14607), 2005-2006 (N = 9150), and 2009-2010 (N = 10848) school years by using multistage stratified designs, with census regions and grades as strata, and school districts as the primary sampling units. African-American and Hispanic students were oversampled to obtain better estimates for those groups. Using the Health Behavior in School-aged Children quadrennial surveys, identical questions assessed BMI, PA, and sedentary and dietary behaviors at each school year. Logistic and linear regression analyses were conducted taking into account the sampling design and controlling for age, gender, race/ethnicity, and family affluence. Across the quadrennial surveys, significant increases were identified in number of days with at least 60 minutes of PA, daily consumption of fruits and vegetables, eating breakfast on weekdays and weekends, and BMI. Television viewing and consumption of sweets and sweetened beverages decreased across this same period. These same patterns were seen in all racial/ethnic groups. These patterns suggest that public health efforts to improve the obesity-related behaviors of US adolescents may be having some success. However, alternative explanations for the increase in BMI over the same period need to be considered.

  6. Contribution to the quantum study of neutral tungsten carbide WC and ionized (WC"q"+, q=1 and 2)

    International Nuclear Information System (INIS)

    Sabor, Said

    2015-01-01

    Metal carbides and oxides are more interesting in catalytic and industrial domains. Tungsten carbide WC has been detected as serious substituent of platinum Pt catalytic. The ultimate goal of this thesis is theoretical studies of electronic structure, stability and the bound nature on WC, WO and its cations. Our preliminary research were motivated by the available spectroscopic data on W, W"+, W"2"+, WC and WC"2"+. We used the methodology (CASSCF/MRCI/MRCI+Q/aug-cc-pV5Z(-PP)) implemented on MOLPRO package to perform quantum calculations with high accuracy taking into account the correlation and relativistic effects with a specific treatment of spin orbit coupling for some low lying excited electronic states of WC"n"+, (n=0, 1 et 2). Our results are shown in good agreement with those available in the literature. Furthermore, in this work for the first time we demonstrated that a carbide dication (WC"2"+) is thermodynamically stable. (author) [fr

  7. Cross-Sectional Associations between Home Environmental Factors and Domain-Specific Sedentary Behaviors in Adults: The Moderating Role of Socio-Demographic Variables and BMI

    Science.gov (United States)

    Busschaert, Cedric; Cardon, Greet; Chastin, Sebastien F. M.; Van Cauwenberg, Jelle; De Cocker, Katrien

    2017-01-01

    Despite the negative health effects of too much sitting, the majority of adults are too sedentary. To develop effective interventions, insight is needed into home environmental correlates of adults’ sedentary behaviors, and into the susceptibility of population subgroups to these home environmental cues. In total, 559 Flemish adults reported socio-demographics, weight and height, home environmental factors and domain-specific sedentary behaviors. Generalized linear modeling was conducted to examine main associations between home environmental factors and domain-specific sedentary behaviors, and to test the moderating role of socio-demographics and BMI on these associations. In case of significant interactions, stratified analyses were performed. Results showed that, among those who did use a computer/laptop during the last week, a one-unit increase in the number of computers or laptops was associated with 17% (OR = 1.17; 95% CI = 1.02, 1.34) and 24% (OR = 1.24; 95% CI = 1.08, 1.43) more minutes computer time per day, respectively. The proximity of the remote controller (p moderated by BMI, with significant positive associations limited to those not overweight. To conclude, home environmental factors were associated with domain-specific sedentary behaviors, especially in healthy weight adults. If confirmed by longitudinal studies, public health professionals should encourage adults to limit the number of indoor entertainment devices and motorized vehicles. PMID:29088089

  8. Objectively assessed physical activity and associated factors of sedentary behavior among survivors of stroke living in Cape Town, South Africa.

    Science.gov (United States)

    Joseph, Conran; Conradsson, David; Hagströmer, Maria; Lawal, Isa; Rhoda, Anthea

    2017-06-18

    To investigate objectively measured physical activity in stroke survivors living in low-income areas of Cape Town, South Africa, specifically to: (a) describe the volume of daily physical activity and time spent in different intensity levels and (b) investigate the association of factors covering the International Classification of Functioning, Disability and Health with sedentary behavior. A cross-sectional design was used, where forty-five ambulatory community-dwelling stroke survivors participated. Volume and intensity of physical activity were assessed with accelerometers for three to five consecutive days. Personal and environmental factors, along with body function and activity, were captured. Multiple linear regression was used to investigate factors associated with the percentage of days spent sedentary. The median number of steps per day was 2393, and of the average 703 minutes of wear time, 80% were spent in sedentary, 15% in light, and 5% in moderate-to-vigorous intensity physical activity. Age, stroke severity, and failing to receive outpatient rehabilitation were independently associated with sedentary, which, taken together, explained 52% of the variance. Low volumes of physical activity and high amount of sedentary time emphasize the need to develop strategies that will increase physical activity. Providing outpatient rehabilitation in a systematic manner post-stroke is a potential target of health care programs in order to reduce sedentary behavior. Implications for rehabilitation Objectively measured physical activity among community-dwelling survivors of stroke in Cape Town, South Africa was low in volume, and the majority did not meet the recommendations of 150 minutes of at least moderate intensity physical activity. The majority of stroke survivors in South Africa spent most of their time sedentary, which could further increase the risk of cardiovascular impairments. Outpatient rehabilitation should be provided to all patients after stroke

  9. Study on single step solid state synthesis of WC@C nanocomposite and electrochemical stability of synthesized WC@C & Pt/WC@C for alcohol oxidation (methanol/ethanol)

    Energy Technology Data Exchange (ETDEWEB)

    Singla, Gourav, E-mail: gsinghla@gmail.com; Singh, K., E-mail: kusingh@thapar.edu; Pandey, O.P., E-mail: oppandey@thapar.edu

    2016-04-25

    WC@C nano composite was prepared by a single step solid–state reaction through in situ reduction and carburization of WO{sub 3} in the presence of Mg and activated charcoal. The XRD results and thermodynamics analysis showed that the optimization of reaction temperature facilitates the reduction as well as carburization of tungsten oxide(s) at different reaction temperature. Thermogravimetric analysis of the product was done to assess the thermal stability in air. The Raman spectroscopy was used to find out the nature (amorphous/graphitic) of carbon in the obtained phase. The N{sub 2} adsorption–desorption measurement showed a narrow pore size distribution from 3 to 4 nm with BET surface area of up to 522.5 m{sup 2}/g. TEM/HRTEM images confirmed formation of the WC nano particles with spherical morphology. Electrochemical stability of pure and platinized carbide sample (Pt/WC) has been investigated using cyclic voltammetry in acidic media for alcohol (methanol and ethanol) oxidation. - Highlights: • Tungsten carbide nano powder was synthesized using charcoal as carbon source. • Formation of WC occurs through the formation of lower tungsten oxide. • CO{sub 2}/CO ratio effect the formation of WC. • Mesoporous tungsten carbide with surface areas 522.5 m{sup 2}/g obtained by using charcoal. • Pt modified WC powder showed higher electrochemical stability.

  10. Physical activity and sedentary behaviors in postpartum Latinas: Madres para la Salud.

    Science.gov (United States)

    Ainsworth, Barbara E; Keller, Colleen; Herrmann, Stephen; Belyea, Michael; Records, Kathryn; Nagle-Williams, Allison; Vega-López, Sonia; Permana, Paska; Coonrod, Dean V

    2013-07-01

    To describe the physical activity (PA) and sedentary behaviors of postpartum Latinas who are overweight or obese before initiating Madres para la Salud, a social support-mediated walking intervention to promote postpartum weight loss. One hundred thirty-nine postpartum women (13.6 ± 7.7 wk since childbirth, age = 28.3 ± 5.6 yr, BMI = 29.7 ± 3.5 kg · m(-2); mean ± SD), recruited from organizations serving Latino residents in the Phoenix, Arizona, area completed the Stanford Brief Activity Survey and concurrently wore an accelerometer (ActiGraph) and a pedometer for 7 d and kept a PA record. Most were classified as inactive and lightly active on the Stanford Brief Activity Survey (51% inactive, 37% light, 11% moderate). Most time was spent in sedentary (512.0 ± 169.9 min · d(-1)) and light-intensity PA (242.4 ± 51.4 min · d(-1)) with less time in moderate-intensity lifestyle (78.3 ± 39.9 min · d(-1)), moderate-intensity walking (16.6 ± 14.4 min · d(-1)), and vigorous-intensity PA (0.34 ± 1.5 min · d(-1)). Pedometer steps per day were low (total = 4973 ± 2202 steps, aerobic = 412 ± 774 steps), with most participants rated as sedentary (61%) or low active (28.1%). Consistent with objective PA measures, PA records showed more time spent in light-intensity PA such as home care, cooking, child care and self-care tasks, occupation, religious events, and watching television. By and large, the postpartum Latinas enrolled spent most of their day in low-intensity activity levels with little time spent in health-enhancing PA levels/behaviors. This demographic should be the focus of PA interventions to increase PA to health-enhancing levels.

  11. Abnormal growth of faceted (WC) grains in a (Co) liquid matrix

    International Nuclear Information System (INIS)

    Park, Y.J.; Yoon, D.Y.

    1996-01-01

    If the grains dispersed in a liquid matrix are spherical, their surface atomic structure is expected to be rough (diffuse), and their coarsening has been observed to be controlled by diffusion in the matrix. They do not, furthermore, undergo abnormal growth. On the other hand, in some compound material systems, the grains in liquid matrices are faceted and often show abnormal coarsening behavior. Their faceted surface planes are expected to be singular (atomically flat) and therefore grow by a defect-assisted process and two-dimensional (2-D) nucleation. Contrary to the usual coarsening theories, their growth velocity is not linearly dependent on the driving force arising from the grain size difference. If the growth of the faceted grains occurs by 2-D nucleation, the rate is expected to increase abruptly at a critical supersaturation, as has been observed in crystal growth in melts and solutions. It is proposed that this growth mechanism leads to the abnormal grain coarsening. The 2-D nucleation theory predicts that there is a threshold initial grain size for the abnormal grain growth (AGG), and the propensity for AGG will increase with the heat-treatment temperature. The AGG behavior will also vary with the defects in the grains. These predictions are qualitatively confirmed in the sintered WC-Co alloy prepared from fine (0.85-microm) and coarse (5.48-microm) WC powders and their mixtures. The observed dependence of the AGG behavior on the sintering temperature and the milling of the WC powder is also qualitatively consistent with the predicted behavior

  12. The influence of physical activity, sedentary behavior on health-related quality of life among the general population of children and adolescents: A systematic review.

    Directory of Open Access Journals (Sweden)

    Xiu Yun Wu

    Full Text Available The association between physical activity, sedentary behavior and health-related quality of life in children and adolescents has been mostly investigated in those young people with chronic disease conditions. No systematic review to date has synthesized the relationship between physical activity, sedentary behavior and health-related quality of life in the general healthy population of children and adolescents. The purpose of this study was to review systematically the existing literature that evaluated the relations between physical activity, sedentary behavior and health-related quality of life in the general population of children and adolescents.We conducted a computer search for English language literature from databases of MEDLINE, EMBASE, PSYCINFO and PubMed-related articles as well as the reference lists of existing literature between 1946 and the second week of January 2017 to retrieve eligible studies. We included the studies that assessed associations between physical activity and/or sedentary behavior and health-related quality of life among the general population of children and adolescents aged between 3-18 years. The study design included cross-sectional, longitudinal and health intervention studies. We excluded the studies that examined associations between physical activity, sedentary behavior and health-related quality of life among children and adolescents with specific chronic diseases, and other studies and reports including reviews, meta-analyses, study protocols, comments, letters, case reports and guidelines. We followed up the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA statement in the reporting of this review. The risk of bias of the primary studies was assessed by the Newcastle-Ottawa Scale. We synthesized the difference in health-related quality of life scores between different levels of physical activity and sedentary time.In total, 31 studies met the inclusion criteria and were

  13. Impulsive approach tendencies towards physical activity and sedentary behaviors, but not reflective intentions, prospectively predict non-exercise activity thermogenesis.

    Science.gov (United States)

    Cheval, Boris; Sarrazin, Philippe; Pelletier, Luc

    2014-01-01

    Understanding the determinants of non-exercise activity thermogenesis (NEAT) is crucial, given its extensive health benefits. Some scholars have assumed that a proneness to react differently to environmental cues promoting sedentary versus active behaviors could be responsible for inter-individual differences in NEAT. In line with this reflection and grounded on the Reflective-Impulsive Model, we test the assumption that impulsive processes related to sedentary and physical activity behaviors can prospectively predict NEAT, operationalized as spontaneous effort exerted to maintain low intensity muscle contractions within the release phases of an intermittent maximal isometric contraction task. Participants (n = 91) completed a questionnaire assessing their intentions to adopt physical activity behaviors and a manikin task to assess impulsive approach tendencies towards physical activity behaviors (IAPA) and sedentary behaviors (IASB). Participants were then instructed to perform a maximal handgrip strength task and an intermittent maximal isometric contraction task. As hypothesized, multilevel regression analyses revealed that spontaneous effort was (a) positively predicted by IAPA, (b) negatively predicted by IASB, and (c) was not predicted by physical activity intentions, after controlling for some confounding variables such as age, sex, usual PA level and average force provided during the maximal-contraction phases of the task. These effects remained constant throughout all the phases of the task. This study demonstrated that impulsive processes may play a unique role in predicting spontaneous physical activity behaviors. Theoretically, this finding reinforces the utility of a motivational approach based on dual-process models to explain inter-individual differences in NEAT. Implications for health behavior theories and behavior change interventions are outlined.

  14. Momentary Assessment of Adults’ Physical Activity and Sedentary Behavior: Feasibility and Validity

    OpenAIRE

    Dunton, Genevieve Fridlund; Liao, Yue; Kawabata, Keito; Intille, Stephen

    2012-01-01

    Introduction: Mobile phones are ubiquitous and easy to use, and thus have the capacity to collect real-time data from large numbers of people. Research tested the feasibility and validity of an Ecological Momentary Assessment (EMA) self-report protocol using electronic surveys on mobile phones to assess adults’ physical activity and sedentary behaviors. Methods: Adults (N = 110) (73% female, 30% Hispanic, 62% overweight/obese) completed a four-day signal-contingent EMA protocol (Sat. - Tues.)...

  15. Sedentary Behavior Is Independently Related to Fat Mass among Children and Adolescents in South China

    Directory of Open Access Journals (Sweden)

    Hongmei Xue

    2016-10-01

    Full Text Available We aim to explore the independent associations of sedentary behaviors (SB with body mass distribution among Chinese children. Data on the screen-based sedentary time (television viewing and computer use and doing homework, physical activities and dietary intake of 1586 Chinese children (50.3% girls aged 7–15 years were obtained through validated questionnaires. Skin-fold thickness, body height, and weight were measured to calculate percent body fat (%BF, fat mass index (FMI, and fat-free mass index (FFMI. Parental characteristics were collected by questionnaires. Among girls, time of SB (screen time or doing homework was positively related to %BF, FMI, and FFMI (p < 0.03 after adjusting for maternal overweight, the average annual income of family, moderate-to-vigorous physical activity energy expenditure, and energy intake: Girls in the highest tertile of screen time/homework had 16.7%/23.3% higher relative FMI and 2.9%/2.9% higher relative FFMI than girls in the lowest tertile. Among boys, screen time was positively associated with FFMI (p < 0.003, but not related to %BF and FMI (p > 0.09, while time of doing homework was positively related to %BF and FMI (p = 0.03. Sedentary behaviors might be positively and independently related to fat mass among Chinese children, and were more pronounced in girls.

  16. Cross-Sectional Associations between Home Environmental Factors and Domain-Specific Sedentary Behaviors in Adults: The Moderating Role of Socio-Demographic Variables and BMI.

    Science.gov (United States)

    Compernolle, Sofie; Busschaert, Cedric; De Bourdeaudhuij, Ilse; Cardon, Greet; Chastin, Sebastien F M; Van Cauwenberg, Jelle; De Cocker, Katrien

    2017-10-31

    Despite the negative health effects of too much sitting, the majority of adults are too sedentary. To develop effective interventions, insight is needed into home environmental correlates of adults' sedentary behaviors, and into the susceptibility of population subgroups to these home environmental cues. In total, 559 Flemish adults reported socio-demographics, weight and height, home environmental factors and domain-specific sedentary behaviors. Generalized linear modeling was conducted to examine main associations between home environmental factors and domain-specific sedentary behaviors, and to test the moderating role of socio-demographics and BMI on these associations. In case of significant interactions, stratified analyses were performed. Results showed that, among those who did use a computer/laptop during the last week, a one-unit increase in the number of computers or laptops was associated with 17% (OR = 1.17; 95% CI = 1.02, 1.34) and 24% (OR = 1.24; 95% CI = 1.08, 1.43) more minutes computer time per day, respectively. The proximity of the remote controller ( p vehicles (95% CI = 0.001, 0.12) was positively associated with the odds of participation in transport-related sitting time. The latter two associations were moderated by BMI, with significant positive associations limited to those not overweight. To conclude, home environmental factors were associated with domain-specific sedentary behaviors, especially in healthy weight adults. If confirmed by longitudinal studies, public health professionals should encourage adults to limit the number of indoor entertainment devices and motorized vehicles.

  17. Flexible Work: The Impact of a New Policy on Employees' Sedentary Behavior and Physical Activity.

    Science.gov (United States)

    Olsen, Heidi M; Brown, Wendy J; Kolbe-Alexander, Tracy; Burton, Nicola W

    2018-01-01

    The aim of the study was to assess change in physical activity (PA) and sedentary behavior (SB) in office-based employees after the implementation of a flexible work policy that allowed working at home. A total of 24 employees (62% female; 40 ± 10 years) completed an online questionnaire 4 weeks pre- and 6 weeks post-implementation of the policy. Changes in PA and SB were assessed using Wilcoxon signed rank test. There were no changes in PA after the introduction of the flexible work policy (Z = -0.29, P > 0.05). Sitting time increased on days the employees worked at home (Z = -2.02, P > 0.05) and on days they worked at the office (Z = -4.16, P > 0.001). A flexible work policy may have had a negative impact on sedentary behavior in this workplace. Future work is needed to explore the potential impact on workplace sitting time.

  18. Influence of socio-economic status on habitual physical activity and sedentary behavior in 8- to 11-year old children.

    Science.gov (United States)

    Drenowatz, Clemens; Eisenmann, Joey C; Pfeiffer, Karin A; Welk, Greg; Heelan, Kate; Gentile, Douglas; Walsh, David

    2010-04-27

    While socio-economic status has been shown to be an important determinant of health and physical activity in adults, results for children and adolescents are less consistent. The purpose of this study, therefore, is to examine whether physical activity and sedentary behavior differs in children by socio-economic status (SES) independent of body mass index. Data were from two cohorts including 271 children (117 males; 154 females) in study 1 and 131 children in study 2 (63 males; 68 females). The average age was 9.6 and 8.8 years respectively. Height and body mass were assessed according to standard procedures and body mass index (BMI, kg/m2) was calculated. Parent-reported household income was used to determine SES. Habitual, free-living physical activity (PA) was assessed by a pedometer (steps/day) in study 1 and accelerometer (time spent in moderate-to-vigorous PA) in study 2. Self-reported time spent watching TV and on the computer was used as measure of sedentary behavior. Differences in PA and sedentary behavior by SES were initially tested using ANOVA. Further analyses used ANCOVA controlling for BMI, as well as leg length in the pedometer cohort. In study 1, mean daily steps differed significantly among SES groups with lower SES groups approximating 10,500 steps/day compared to about 12,000 steps/day in the higher SES groups. These differences remained significant (p depended on the methodology used to determine time spent in moderate-to-vigorous physical activity (MVPA). Only one equation resulted in significant group differences (p = 0.015), and these differences remained after controlling for BMI. Significant differences between SES groups were shown for sedentary behavior in both cohorts (P < 0.05) with higher SES groups spending less time watching TV than low SES groups. Children from a low SES show a trend of lower PA levels and spend more time in sedentary behavior than high SES children; however, differences in PA were influenced by BMI. The higher

  19. The Effect of Changes in Physical Activity on Sedentary Behavior: Results From a Randomized Lifestyle Intervention Trial.

    Science.gov (United States)

    Siddique, Juned; de Chavez, Peter John; Craft, Lynette L; Freedson, Patty; Spring, Bonnie

    2017-07-01

    To investigate whether changes in physical activity (PA) have an impact on sedentary behavior (SB) during a lifestyle intervention. Study design was a randomized trial. Participants (n = 204) were individuals with low PA and high sedentary leisure screen time from the Chicago area. Participants were randomized to either increase PA (iPA) or decrease sedentary leisure (dSED). The intervention consisted of decision support, coaching, and financial incentives. For iPA participants, the goal was at least 60 min/d of self-reported moderate-tovigorous-intensity PA (MVPA). For dSED participants the goal was less than 90 min/d of sedentary leisure screen time. Daily accelerometer-based measures of SB and bout-corrected MVPA were obtained. Linear mixed-effects models were fit to estimate the effect of the intervention on MVPA and total SB and to estimate the effect of daily changes in MVPA on daily SB. The iPA participants increased their bout-corrected MVPA by 14 min/d (p much of this time by reducing their SB.

  20. Sedentary behavior and physical activity levels in people with schizophrenia, bipolar disorder and major depressive disorder: a global systematic review and meta-analysis.

    Science.gov (United States)

    Vancampfort, Davy; Firth, Joseph; Schuch, Felipe B; Rosenbaum, Simon; Mugisha, James; Hallgren, Mats; Probst, Michel; Ward, Philip B; Gaughran, Fiona; De Hert, Marc; Carvalho, André F; Stubbs, Brendon

    2017-10-01

    People with severe mental illness (schizophrenia, bipolar disorder or major depressive disorder) die up to 15 years prematurely due to chronic somatic comorbidities. Sedentary behavior and low physical activity are independent yet modifiable risk factors for cardiovascular disease and premature mortality in these people. A comprehensive meta-analysis exploring these risk factors is lacking in this vulnerable population. We conducted a meta-analysis investigating sedentary behavior and physical activity levels and their correlates in people with severe mental illness. Major electronic databases were searched from inception up to April 2017 for articles measuring sedentary behavior and/or physical activity with a self-report questionnaire or an objective measure (e.g., accelerometer). Random effects meta-analyses and meta-regression analyses were conducted. Sixty-nine studies were included (N=35,682; 39.5% male; mean age 43.0 years). People with severe mental illness spent on average 476.0 min per day (95% CI: 407.3-545.4) being sedentary during waking hours, and were significantly more sedentary than age- and gender-matched healthy controls (p=0.003). Their mean amount of moderate or vigorous physical activity was 38.4 min per day (95% CI: 32.0-44.8), being significantly lower than that of healthy controls (p=0.002 for moderate activity, pphysical activity guidelines (odds ratio = 1.5; 95% CI: 1.1-2.0, pphysical activity levels and non-compliance with physical activity guidelines were associated with male gender, being single, unemployment, fewer years of education, higher body mass index, longer illness duration, antidepressant and antipsychotic medication use, lower cardiorespiratory fitness and a diagnosis of schizophrenia. People with bipolar disorder were the most physically active, yet spent most time being sedentary. Geographical differences were detected, and inpatients were more active than outpatients and those living in the community. Given the

  1. Urban-Rural Differences in Aerobic Physical Activity, Muscle Strengthening Exercise, and Screen-Time Sedentary Behavior.

    Science.gov (United States)

    Robertson, Michael C; Song, Jaejoon; Taylor, Wendell C; Durand, Casey P; Basen-Engquist, Karen M

    2018-02-16

    Compared to their urban counterparts, US residents in rural settings face an increased risk of premature mortality and health problems that have been linked to insufficient physical activity (PA) levels. There is limited literature regarding urban-rural differences in adherence to national guidelines for all 3 PA-related behaviors. We investigated urban-rural differences in aerobic PA, leisure-time muscle strengthening PA, and leisure screen-time sedentary behavior in a combined data set of the 2011-2014 waves (N = 14,188) of the nationally representative National Cancer Institute's Health Information National Trends Survey. We found no evidence of a difference between large urban and rural residents' aerobic PA levels. The typical number of weekly bouts of leisure-time muscle strengthening PA was 25% lower for rural residents (incidence rate ratio [IRR] = 0.751, P rural residents to engage in 6.6% less daily leisure screen-time sedentary behavior than their large urban counterparts (IRR = 0.934, P = .031). Taken together with previous literature, these results suggest that rural residents may engage in comparable levels of total PA, but less leisure-time PA, than their urban counterparts. © 2018 National Rural Health Association.

  2. Metal modified tungsten carbide (WC) for catalytic and electrocatalytic applications

    Science.gov (United States)

    Mellinger, Zachary J.

    One of the major challenges in the commercialization of proton exchange membrane fuel cells (PEMFC) is the cost, and low CO tolerance of the anode electrocatalyst material. The anode typically requires a high loading of precious metal electrocatalyst (Pt or Pt--Ru) to obtain a useful amount of electrical energy from the electrooxidation of methanol (CH3OH) or ethanol (C2H5OH). The complete electro--oxidation of methanol or ethanol on these catalysts produces strongly adsorbed CO on the surface, which reduces the activity of the Pt or Pt--Ru catalysts. Another major disadvantage of these electrocatalyst components is the scarcity and consequently high price of both Pt and Ru. Tungsten monocarbide (WC) has shown similar catalytic properties to Pt, leading to the utilization of WC and metal modified WC as replacements to Pt and Pt--Ru. In this thesis we investigated WC and Pt--modified WC as a potentially more CO--tolerant electrocatalysts as compared to pure Pt. These catalysts would reduce or remove the high loading of Pt used industrially. The binding energy of CO, estimated using temperature programmed desorption, is weaker on WC and Pt/WC than on Pt, suggesting that it should be easier to oxidize CO on WC and Pt/WC. This hypothesis was verified using cyclic voltammetry to compare the electro--oxidation of CO on WC, Pt/WC, and Pt supported on carbon substrates, which showed a lower voltage for the onset of oxidation of CO on WC and Pt/WC than on Pt. After observing these improved properties on the Pt/WC catalysts, we decided to expand our studies to investigate Pd--modified WC as Pd is less expensive than Pt and has shown more ideal properties for alcohol electrocatalysis in alkaline media. Pd/WC showed a lower binding energy of CO than both its parent metal Pd as well as Pt. Then, density functional theory (DFT) calculations were performed to determine how the presence of Pd affected the bonding of methanol and ethanol on the WC surface. The DFT studies showed

  3. Compression deformation of WC: atomistic description of hard ceramic material

    Science.gov (United States)

    Feng, Qing; Song, Xiaoyan; Liu, Xuemei; Liang, Shuhua; Wang, Haibin; Nie, Zuoren

    2017-11-01

    The deformation characteristics of WC, as a typical hard ceramic material, were studied on the nanoscale using atomistic simulations for both the single-crystal and polycrystalline forms under uniaxial compression. In particular, the effects of crystallographic orientation, grain boundary coordination and grain size on the origin of deformation were investigated. The deformation behavior of the single-crystal and polycrystalline WC both depend strongly on the orientation towards the loading direction. The grain boundaries play a significant role in the deformation coordination and the potential high fracture toughness of the nanocrystalline WC. In contrast to conventional knowledge of ceramics, maximum strength was obtained at a critical grain size corresponding to the turning point from a Hall-Petch to an inverse Hall-Petch relationship. For this the mechanism of the combined effect of dislocation motion within grains and the coordination of stress concentration at the grain boundaries were proposed. The present work has moved forward our understanding of plastic deformability and the possibility of achieving a high strength of nanocrystalline ceramic materials.

  4. Impulsive approach tendencies towards physical activity and sedentary behaviors, but not reflective intentions, prospectively predict non-exercise activity thermogenesis.

    Directory of Open Access Journals (Sweden)

    Boris Cheval

    Full Text Available Understanding the determinants of non-exercise activity thermogenesis (NEAT is crucial, given its extensive health benefits. Some scholars have assumed that a proneness to react differently to environmental cues promoting sedentary versus active behaviors could be responsible for inter-individual differences in NEAT. In line with this reflection and grounded on the Reflective-Impulsive Model, we test the assumption that impulsive processes related to sedentary and physical activity behaviors can prospectively predict NEAT, operationalized as spontaneous effort exerted to maintain low intensity muscle contractions within the release phases of an intermittent maximal isometric contraction task. Participants (n = 91 completed a questionnaire assessing their intentions to adopt physical activity behaviors and a manikin task to assess impulsive approach tendencies towards physical activity behaviors (IAPA and sedentary behaviors (IASB. Participants were then instructed to perform a maximal handgrip strength task and an intermittent maximal isometric contraction task. As hypothesized, multilevel regression analyses revealed that spontaneous effort was (a positively predicted by IAPA, (b negatively predicted by IASB, and (c was not predicted by physical activity intentions, after controlling for some confounding variables such as age, sex, usual PA level and average force provided during the maximal-contraction phases of the task. These effects remained constant throughout all the phases of the task. This study demonstrated that impulsive processes may play a unique role in predicting spontaneous physical activity behaviors. Theoretically, this finding reinforces the utility of a motivational approach based on dual-process models to explain inter-individual differences in NEAT. Implications for health behavior theories and behavior change interventions are outlined.

  5. Modeling how substitution of sedentary behavior with standing or physical activity is associated with health-related quality of life in colorectal cancer survivors

    OpenAIRE

    van Roekel, Eline H.; Bours, Martijn J. L.; Breedveld-Peters, Jos? J. L.; Willems, Paul J. B.; Meijer, Kenneth; Kant, IJmert; van den Brandt, Piet A.; Beets, Geerard L.; Sanduleanu, Silvia; Weijenberg, Matty P.

    2016-01-01

    Purpose Previous research indicates that sedentary behavior is unfavorably associated with health-related quality of life (HRQoL) of colorectal cancer (CRC) survivors. Using isotemporal substitution modeling, we studied how substituting sedentary behavior with standing or physical activity was associated with HRQoL in CRC survivors, 2?10?years post-diagnosis. Methods A cross-sectional study was conducted in stage I?III CRC survivors (n?=?145) diagnosed at Maastricht University Medical Center+...

  6. Independent and Combined Associations of Physical Activity and Sedentary Behavior with Depressive Symptoms Among Japanese Adults.

    Science.gov (United States)

    Liao, Yung; Shibata, Ai; Ishii, Kaori; Oka, Koichiro

    2016-08-01

    Associations between levels of sedentary behavior and depressive symptoms independently and in combination with different levels of physical activity remain unclear. This study aimed to examine independent and combined associations of physical activity (PA) and sedentary behavior (SB) with depressive symptoms among Japanese adults. An Internet-based survey collected data on depression levels (Center for Epidemiologic Studies Depression Scale), self-reported time spent in PA and SB (Japanese short version of the International Physical Activity Questionnaire), and sociodemographic variables from 2,914 adults in 2009. Binary logistic regression analyses were conducted to examine the odds ratios (ORs) for being depressed (depression scores ≥16) according to independent PA levels (none, insufficient, sufficient), SB levels (low, moderate, high), and nine combinations of PA and SB categories. After adjusting for potential confounders, sufficient PA level was found to be related to lower risk of depressive symptoms independently (OR = 0.61), whereas no significant associations were observed between SB levels and depression. In the combined associations, adults in the sufficient PA/high SB (OR = 0.44), sufficient PA/moderate SB (OR = 0.56), and sufficient PA/low SB (OR = 0.57) categories were significantly less likely to have depressive symptoms in comparison with the no PA/high SB category. Meeting physical activity recommendations is associated with a lower risk of depressive symptoms, regardless of time spent in total sedentary behavior. These results suggest that promoting physical activity may be an effective strategy against depressive symptoms among Japanese adults.

  7. Sampling and analysis of the inactive waste tanks TH-2, WC-1, and WC-15

    International Nuclear Information System (INIS)

    Autrey, J.W.; Keller, J.M.; Griest, W.H.; Botts, J.L.; Schenley, R.L.; Sipe, M.A.

    1992-02-01

    Thirty-eight inactive liquid low-level radioactive waste tanks are currently managed by the Environmental Restoration Program of Oak Ridge National Laboratory. The contents of these tanks are to be characterized in preparation for future corrective actions and remediation activities as part of compliance with the pending Federal Facility Agreement for the Oak Ridge Reservation. Twenty-nine of these tanks were sampled and analyzed in 1989. Three of the tanks (TH-2, WC-1, and WC-15) were not accessible from the surface and thus were not sampled until 1990. This report presents the sampling and analytical results of that campaign. All three tanks in this report had negligible regulatory organic compounds in the samples that were collected. There were no US Environmental Protection Agency (EPA) Target Compound List (TCL) constituents for volatile organics detected in any of the aqueous samples. The only semivolatile organics detected were 2-chlorophenol (52 μg/L) in tank TH-2 and dichloroethane (14--15 μg/L) and diethyl either (15--17 μg/L) in tank WC-15. A thin oil layer was discovered floating on top of the aqueous contents in tank WC-15. The analysis of the oil layer detected no volatile organics and showed only one EPA TCL constituent, di-n-butylphthalate, at 1900 μg/L. Low levels of Resource Conservation and Recovery Act (RCRA) metals were observed in the samples from tank TH-2, but only the mercury level exceeded the RCRA limit. Samples from tank WC-1 had elevated levels of the RCRA metals barium, chromium, and lead. There were also finely suspended particles in one of the samples from tank WC-1, which was filtered and analyzed separately. This solid fines have levels of transuranium elements 238 Pu and 241 Am high enough to classified as transuranic waste

  8. Associations between accelerometer-assessed sedentary behavior, physical activity and objectively-measured cardiorespiratory fitness with red blood cell distribution width.

    Science.gov (United States)

    Edwards, Meghan K; Loprinzi, Paul D

    2016-10-15

    Emerging work identifies red blood cell distribution width (RDW) as a unique biomarker independently associated with cardiovascular disease and mortality. Encouragingly, recent research demonstrates individual associations of sedentary behavior, physical activity and cardiorespiratory fitness with RDW. However, no study has evaluated their independent and combined associations on RDW, which was this study's purpose. Data from the 2003-2004 National Health and Nutrition Examination Survey were used (N=627 adults 20-49yrs). Sedentary behavior and MVPA were objectively assessed (accelerometry) with cardiorespiratory fitness determined from a submaximal treadmill-based test. Participants were classified as above or below the median values for each of these three parameters, with a PACS (Physical Activity Cardiorespiratory Sedentary) score ranging from 0 to 3, indicating the participant number of these three positive characteristics. A blood sample was obtained from each participant to assess RDW. Only above median MVPA (OR=0.47; 95% CI: 0.32-0.68) was independently associated with a reduced odds of having an elevated RDW. With regard to the additive model, and after adjustment, the odds ratio (95% CI) for the PACS score of 1 (vs. 0), 2 (vs. 0), and 3 (vs. 0), respectively, were 0.81 (0.45-1.45; P=0.46), 0.66 (0.44-0.99; P=0.04) and 0.35 (0.18-0.68; P=0.004). When considering sedentary behavior, MVPA, and cardiorespiratory fitness, only MVPA was associated with reduced odds of elevated RDW, but those with all three characteristics had the lowest odds of elevated RDW. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Associations of street layout with walking and sedentary behaviors in an urban and a rural area of Japan.

    Science.gov (United States)

    Koohsari, Mohammad Javad; Sugiyama, Takemi; Shibata, Ai; Ishii, Kaori; Liao, Yung; Hanibuchi, Tomoya; Owen, Neville; Oka, Koichiro

    2017-05-01

    We examined whether street layout -a key urban design element- is associated with walking and sedentary behaviors in the context of a non-Western country; and, whether such associations differ between an urban and a rural area. In 2011, 1076 middle-to-older aged adults living in an urban and a rural area of Japan reported their walking and sedentary (sitting) behaviors. Two objective measures of street layout (intersection density and street integration) were calculated. Participants exposed to more-connected street layouts were more likely to walk for commuting and for errands, to meet physical activity recommendations through walking for commuting, and less likely to drive. These relationships differed between the urban and the rural area. This shows that previous findings from Western countries on associations of street connectivity with travel behaviors may also be applicable to Japan. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Influence of socio-economic status on habitual physical activity and sedentary behavior in 8- to 11-year old children

    Directory of Open Access Journals (Sweden)

    Heelan Kate

    2010-04-01

    Full Text Available Abstract Background While socio-economic status has been shown to be an important determinant of health and physical activity in adults, results for children and adolescents are less consistent. The purpose of this study, therefore, is to examine whether physical activity and sedentary behavior differs in children by socio-economic status (SES independent of body mass index. Methods Data were from two cohorts including 271 children (117 males; 154 females in study 1 and 131 children in study 2 (63 males; 68 females. The average age was 9.6 and 8.8 years respectively. Height and body mass were assessed according to standard procedures and body mass index (BMI, kg/m2 was calculated. Parent-reported household income was used to determine SES. Habitual, free-living physical activity (PA was assessed by a pedometer (steps/day in study 1 and accelerometer (time spent in moderate-to-vigorous PA in study 2. Self-reported time spent watching TV and on the computer was used as measure of sedentary behavior. Differences in PA and sedentary behavior by SES were initially tested using ANOVA. Further analyses used ANCOVA controlling for BMI, as well as leg length in the pedometer cohort. Results In study 1, mean daily steps differed significantly among SES groups with lower SES groups approximating 10,500 steps/day compared to about 12,000 steps/day in the higher SES groups. These differences remained significant (p Conclusions Children from a low SES show a trend of lower PA levels and spend more time in sedentary behavior than high SES children; however, differences in PA were influenced by BMI. The higher BMI in these children might be another factor contributing to increased health risks among low SES children compared to children from with a higher SES.

  11. Physical activity level and sedentary behavior among students

    Directory of Open Access Journals (Sweden)

    Roberto Jerônimo dos Santos Silva

    2009-06-01

    Full Text Available The objective of this study was to determine the physical activity level (PAL and sedentary behavior of students from the city of Aracaju (SE. A total of 1028 students of both genders participated in the study, with a mean age of 15.38 (2.44 years for girls and 15.24 (2.40 years for boys. Among the sample, 24.7% were children and 75.3% were adolescents, with a mean age of 12.07 (0.88 and 16.39 (1.72 years, respectively. An instrument already used in Brazilian studies was applied to identify the average time (hours watching TV per day (hTV and PAL – PAQ-C. Descriptive statistics, t-test for independent samples, Fisher’s exact test and comparison test between two proportions were used for data analysis, with the level of significance set at 5% (p≤0.05. Boys presented a significantly higher physical activity score 2.25 (0.60 than girls. The prevalence of sedentarism was 72.5, 89.3 and 85.2% in the groups of children and adolescents and in the group as a whole, respectively, for girls, and 55.4, 74.8 and 69.8% for boys. No differences in hTV were observed between genders or between sedentary and physically active students (p > 0.05. We conclude that a there is a high prevalence of “sedentary” and “very sedentary” children and adolescents; b boys present a higher PAL than girls; c adolescents are less active than children, and d the number of hTV is high in the group studied.

  12. Impact of trained champions of comprehensive school physical activity programs on school physical activity offerings, youth physical activity and sedentary behaviors.

    Science.gov (United States)

    Carson, Russell L; Castelli, Darla M; Pulling Kuhn, Ann C; Moore, Justin B; Beets, Michael W; Beighle, Aaron; Aija, Rahma; Calvert, Hannah G; Glowacki, Elizabeth M

    2014-12-01

    A quasi-experimental cluster-controlled design was used to test the impact of comprehensive school physical activity program (CSPAP) professional development on changes in school physical activity (PA) offerings, moderate-to-vigorous physical activity (MVPA) and sedentary behaviors of 9-14 year-old children during school. Two groups of Louisiana elementary and middle school physical education teachers (N=129) attended a CSPAP summer workshop (95 in 2012=intervention, 34 in 2013=control) and were assessed on school PA offerings (teacher-reported; pre, mid, and post). During the 2012-2013 school year, intervention teachers received CSPAP support while implementing new school PA programs. MVPA and sedentary behaviors were assessed (accelerometry; baseline and post) on a sample of 231 intervention, 120 control students from 16 different schools. Multivariate analysis of covariance indicated that intervention teachers reported significantly more PA offerings during school (3.35 vs. 2.37) and that involve staff (1.43 vs. 0.90). Three-level, mixed model regressions (stratified by sex) indicated that students overall spent less time in MVPA and more time being sedentary during school, but the effects were significantly blunted among intervention students, especially boys. This study provides preliminary evidence for CSPAP professional development programs to influence school-level PA offerings and offset student-level declines in MVPA and increases in sedentary behavior. Published by Elsevier Inc.

  13. Parent dietary, physical activity and sedentary behaviors associated with child behaviors and weight status among private school children in Delhi, India: A cross-sectional study

    OpenAIRE

    Blanche Greene-Cramer

    2016-01-01

    Background Family can be an important socializing agent that strongly influences child and adolescent behavior. While studies have found associations between parent modeling of healthy behaviors and these behaviors in children in the US and other western countries, there is a dearth of research examining these associations among low and middle-income countries like India. This study examines the association between parent dietary, physical activity, and sedentary behaviors and child behavi...

  14. [Association between sedentary life style and risks of metabolic syndrome and diabetes mellitus type 2].

    Science.gov (United States)

    Ye, Ying; Zhong, Wenling; Lin, Xiuquan; Lin, Shuguang; Lin, Xi; Li, Xiaoqing; Chen, Tiehui

    2014-11-01

    To explore the association of sedentary life style with risk of metabolic syndrome (MS) and diabetes mellitus type 2(T2DM). A total of 6 016 local residents aged 18 years or older in Fujian province were recruited by multi-stage stratified cluster sampling method in 2010-2011. Data, including demographic information, physical activity and sedentary time were collected. Indices related to height, weight, waist circumference, blood pressure and blood lipid were determined while MS and T2DM were diagnosed by IDF (2005) and WHO (1999) criteria. Logistic regression was used to estimate the correlations between sedentary behavior and MS or T2DM. The prevalence rates of MS and T2DM were 19.0% and 8.0% respectively, in local residents aged 18 years or older, in Fujian province. The overall rate of sedentary behavior was 18.1%, with the mean sedentary time as 4.3 hours. Both data showed significantly differences (P sedentary time sedentary behavior was independently associated with an increased risk of MT group (OR = 1.82, 95% CI: 1.33-2.48, P sedentary behavior/sedentary time. MS and T2DM were associated with sedentary lifestyle, but these findings should be confirmed through further longitudinal studies.

  15. Using the intervention mapping protocol to reduce European preschoolers’ sedentary behavior, an application to the ToyBox-Study

    Science.gov (United States)

    2014-01-01

    Background High levels of sedentary behavior are often measured in preschoolers, but only a few interventions have been developed to counteract this. Furthermore, detailed descriptions of interventions in preschoolers targeting different forms of sedentary behavior could not be located in the literature. The aim of the present paper was to describe the different steps of the Intervention Mapping Protocol used towards the development of an intervention component of the ToyBox-study focusing on decreasing preschoolers’ sedentary behavior. The ToyBox-study focuses on the prevention of overweight in 4- to 6-year-old children by implementing a multi-component kindergarten-based intervention with family involvement in six different European countries. Methods Applying the Intervention Mapping Protocol, six different steps were systematically completed for the structured planning and development of the intervention. A literature search and results from focus groups with parents/caregivers and kindergarten teachers were used as a guide during the development of the intervention and the intervention materials. Results The application of the different steps in the Intervention Mapping Protocol resulted in the creation of matrices of change objectives, followed by the selection of practical applications for five different intervention tools that could be used at the individual level of the preschool child, at the interpersonal level (i.e., parents/caregivers) and at the organizational level (i.e., kindergarten teachers). No cultural differences regarding preschoolers’ sedentary behavior were identified between the participating countries during the focus groups, so cultural and local adaptations of the intervention materials were not necessary to improve the adoption and implementation of the intervention. Conclusions A systematic and evidence-based approach was used for the development of this kindergarten-based family-involved intervention targeting preschoolers, with

  16. Using the intervention mapping protocol to reduce European preschoolers' sedentary behavior, an application to the ToyBox-Study.

    Science.gov (United States)

    De Decker, Ellen; De Craemer, Marieke; De Bourdeaudhuij, Ilse; Verbestel, Vera; Duvinage, Kristin; Iotova, Violeta; Grammatikaki, Evangelia; Wildgruber, Andreas; Mouratidou, Theodora; Manios, Yannis; Cardon, Greet

    2014-02-19

    High levels of sedentary behavior are often measured in preschoolers, but only a few interventions have been developed to counteract this. Furthermore, detailed descriptions of interventions in preschoolers targeting different forms of sedentary behavior could not be located in the literature. The aim of the present paper was to describe the different steps of the Intervention Mapping Protocol used towards the development of an intervention component of the ToyBox-study focusing on decreasing preschoolers' sedentary behavior. The ToyBox-study focuses on the prevention of overweight in 4- to 6-year-old children by implementing a multi-component kindergarten-based intervention with family involvement in six different European countries. Applying the Intervention Mapping Protocol, six different steps were systematically completed for the structured planning and development of the intervention. A literature search and results from focus groups with parents/caregivers and kindergarten teachers were used as a guide during the development of the intervention and the intervention materials. The application of the different steps in the Intervention Mapping Protocol resulted in the creation of matrices of change objectives, followed by the selection of practical applications for five different intervention tools that could be used at the individual level of the preschool child, at the interpersonal level (i.e., parents/caregivers) and at the organizational level (i.e., kindergarten teachers). No cultural differences regarding preschoolers' sedentary behavior were identified between the participating countries during the focus groups, so cultural and local adaptations of the intervention materials were not necessary to improve the adoption and implementation of the intervention. A systematic and evidence-based approach was used for the development of this kindergarten-based family-involved intervention targeting preschoolers, with the inclusion of parental involvement. The

  17. Comparison of Obesity, Physical Activity, and Sedentary Behaviors between Adolescents with Autism Spectrum Disorders and Without

    Science.gov (United States)

    McCoy, Stephanie M.; Jakicic, John M.; Barone Gibbs, Bethany

    2016-01-01

    Body mass index classification, physical activity (PA), and sedentary behaviors were compared in adolescents with autism spectrum disorder (ASD) to typically developing adolescents. Participants included 42,747 adolescents (ASD, n = 915) from the 2011-2012 National Survey of Children's Health. After controlling for covariates, adolescents were…

  18. [Sedentary lifestyle is associated with metabolic and cardiovascular risk factors independent of physical activity].

    Science.gov (United States)

    Leiva, Ana María; Martínez, María Adela; Cristi-Montero, Carlos; Salas, Carlos; Ramírez-Campillo, Rodrigo; Díaz Martínez, Ximena; Aguilar-Farías, Nicolás; Celis-Morales, Carlos

    2017-04-01

    Sedentary behavior is a main risk factor for cardiovascular disease and mortality. To investigate the association between sedentary behavior and metabolic and cardiovascular risk factors. We assessed 322 participants aged between 18 to 65 years. Physical activity and sedentary behavior were measured with accelerometers (Actigraph®). Body mass index (BMI), waist circumference, percentage of body fat, diet and blood markers (glucose, lipid profile, insulin and HOMA-IR) were measured with standardized protocols. Thirty four percent of participants were physically inactive and spent on average 8.7 h/day on sedentary activities. Per one hour increase in sedentary behavior there were significant adverse changes in glucose (4.79 mg/dl), insulin (2.73 pmol/l), HOMA-IR (0.75), BMI (0.69 kg/m²), waist circumference (1.95 cm), fat mass (1.03%), total cholesterol (9.73 mg/dl), HDL-cholesterol (-3.50 mg/dl), LDL-cholesterol (10.7 mg/dl) and triglycerides (12.4 mg/dl). These findings were independent of main confounding factors including total physical activity, dietary factors, BMI and socio-demographics. The detrimental effect of sedentary behaviors on cardiometabolic and obesity-related traits is independent of physical activity levels. Therefore, reducing sedentary time should be targeted in the population apart from increasing their physical activity levels.

  19. Patterns of sedentary behavior in overweight and moderately obese users of the Catalan primary-health care system.

    Directory of Open Access Journals (Sweden)

    Elena Martínez-Ramos

    Full Text Available Prolonged sitting time (ST has negative consequences on health. Changing this behavior is paramount in overweight/obese individuals because they are more sedentary than those with normal weight. The aim of the study was to establish the pattern of sedentary behavior and its relationship to health, socio-demographics, occupation, and education level in Catalan overweight/obese individuals.A descriptive study was performed at 25 healthcare centers in Catalonia (Spain with 464 overweight/moderately obese patients, aged25 to 65 years. Exclusion criteria were chronic diseases which contraindicated physical activity and language barriers. Face-to-face interviews were conducted to collect data on age, gender, educational level, social class, and marital status. Main outcome was 'sitting time' (collected by the Marshall questionnaire; chronic diseases and anthropometric measurements were registered.464 patients, 58.4% women, mean age 51.9 years (SD 10.1, 76.1% married, 60% manual workers, and 48.7% had finished secondary education. Daily sitting time was 6.2 hours on working days (374 minutes/day, SD: 190, and about 6 hours on non-working ones (357 minutes/day, SD: 170. 50% of participants were sedentary ≥6 hours. The most frequent sedentary activities were: working/academic activities around 2 hours (128 minutes, SD: 183, followed by watching television, computer use, and commuting. Men sat longer than women (64 minutes more on working days and 54 minutes on non-working days, and individuals with office jobs (91 minutes,those with higher levels of education (42 minutes, and younger subjects (25 to 35 years spent more time sitting.In our study performed in overweight/moderately obese patients the mean sitting time was around 6 hours which was mainly spent doing work/academic activities and watching television. Men, office workers, individuals with higher education, and younger subjects had longer sitting time. Our results may help design interventions

  20. Physical activity level and sedentary behavior among students

    Directory of Open Access Journals (Sweden)

    Diego Augusto Santos Silva

    2009-01-01

    Full Text Available http://dx.doi.org/10.5007/1980-0037.2009v11n3p299   The objective of this study was to determine the physical activity level (PAL and sedentary behavior of students from the city of Aracaju (SE. A total of 1028 students of both genders participated in the study, with a mean age of 15.38 (2.44 years for girls and 15.24 (2.40 years for boys. Among the sample, 24.7% were children and 75.3% were adolescents, with a mean age of 12.07 (0.88 and 16.39 (1.72 years, respectively. An instrument already used in Brazilian studies was applied to identify the average time (hours watching TV per day (hTV and PAL – PAQ-C. Descriptive statistics, t-test for independent samples, Fisher’s exact test and comparison test between two proportions were used for data analysis, with the level of significance set at 5% (p≤0.05. Boys presented a significantly higher physical activity score 2.25 (0.60 than girls. The prevalence of sedentarism was 72.5, 89.3 and 85.2% in the groups of children and adolescents and in the group as a whole, respectively, for girls, and 55.4, 74.8 and 69.8% for boys. No differences in hTV were observed between genders or between sedentary and physically active students (p > 0.05. We conclude that a there is a high prevalence of “sedentary” and “very sedentary” children and adolescents; b boys present a higher PAL than girls; c adolescents are less active than children, and d the number of hTV is high in the group studied.

  1. Physical Activity and Sedentary Behaviors Associated With Risk of Progression From Gestational Diabetes Mellitus to Type 2 Diabetes Mellitus

    DEFF Research Database (Denmark)

    Bao, Wei; Tobias, Deirdre K; Bowers, Katherine

    2014-01-01

    IMPORTANCE: Women with a history of gestational diabetes mellitus (GDM) are at substantially increased risk of type 2 diabetes mellitus (T2DM). The identification of important modifiable factors could help prevent T2DM in this high-risk population. OBJECTIVE: To examine the role of physical...... activity and television watching and other sedentary behaviors, and changes in these behaviors in the progression from GDM to T2DM. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of 4554 women from the Nurses' Health Study II who had a history of GDM, as part of the ongoing Diabetes & Women......'s Health Study. These women were followed up from 1991 to 2007. EXPOSURES: Physical activity and television watching and other sedentary behaviors were assessed in 1991, 1997, 2001, and 2005. MAIN OUTCOMES AND MEASURE: Incident T2DM identified through self-report and confirmed by supplemental...

  2. Obesity, physical activity and sedentary behavior amongst British and Saudi youth: a cross-cultural study.

    Science.gov (United States)

    Al-Nakeeb, Yahya; Lyons, Mark; Collins, Peter; Al-Nuaim, Anwar; Al-Hazzaa, Hazzaa; Duncan, Michael J; Nevill, Alan

    2012-04-01

    This study explores differences in weight status, obesity and patterns of physical activity (PA) in relation to gender and age of youth from two culturally, environmentally and geographically diverse countries, the United Kingdom (UK) and Saudi Arabia (SA). A total of 2,290 males and females (15-17 years) volunteered to participate in this study. Participants completed a validated self-report questionnaire that contained 47 items relating to patterns of PA, sedentary activity and eating habits. The questionnaire allows the calculation of total energy expenditure in metabolic equivalent (MET-min) values per week. Significant differences in percentage of overweight/obese and levels of PA were evident between the youth from the two countries, with males being generally more physically active than females. Additionally, there were significant associations between Body Mass Index (BMI), PA and sedentary behaviors; the youth with higher BMI reported lower levels of PA and higher amounts of sedentary time. These findings highlight the diverse nature of lifestyle of youth living in different geographical areas of the world and the need for further research to explore the socio-cultural factors that impact on the prevalence of obesity and patterns of PA of youth in different populations.

  3. Direct laser sintered WC-10Co/Cu nanocomposites

    Science.gov (United States)

    Gu, Dongdong; Shen, Yifu

    2008-04-01

    In the present work, the direct metal laser sintering (DMLS) process was used to prepare the WC-Co/Cu nanocomposites in bulk form. The WC reinforcing nanoparticles were added in the form of WC-10 wt.% Co composite powder. The microstructural features and mechanical properties of the laser-sintered sample were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and nanoindentation tester. It showed that the original nanometric nature of the WC reinforcing particulates was well retained without appreciable grain growth after laser processing. A homogeneous distribution of the WC reinforcing nanoparticles with a coherent particulate/matrix interfacial bonding was obtained in the laser-sintered structure. The 94.3% dense nanocomposites have a dynamic nanohardness of 3.47 GPa and a reduced elastic modulus of 613.42 GPa.

  4. Direct laser sintered WC-10Co/Cu nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Gu Dongdong [College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016 (China)], E-mail: dongdonggu@nuaa.edu.cn; Shen Yifu [College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016 (China)

    2008-04-30

    In the present work, the direct metal laser sintering (DMLS) process was used to prepare the WC-Co/Cu nanocomposites in bulk form. The WC reinforcing nanoparticles were added in the form of WC-10 wt.% Co composite powder. The microstructural features and mechanical properties of the laser-sintered sample were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and nanoindentation tester. It showed that the original nanometric nature of the WC reinforcing particulates was well retained without appreciable grain growth after laser processing. A homogeneous distribution of the WC reinforcing nanoparticles with a coherent particulate/matrix interfacial bonding was obtained in the laser-sintered structure. The 94.3% dense nanocomposites have a dynamic nanohardness of 3.47 GPa and a reduced elastic modulus of 613.42 GPa.

  5. Direct laser sintered WC-10Co/Cu nanocomposites

    International Nuclear Information System (INIS)

    Gu Dongdong; Shen Yifu

    2008-01-01

    In the present work, the direct metal laser sintering (DMLS) process was used to prepare the WC-Co/Cu nanocomposites in bulk form. The WC reinforcing nanoparticles were added in the form of WC-10 wt.% Co composite powder. The microstructural features and mechanical properties of the laser-sintered sample were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and nanoindentation tester. It showed that the original nanometric nature of the WC reinforcing particulates was well retained without appreciable grain growth after laser processing. A homogeneous distribution of the WC reinforcing nanoparticles with a coherent particulate/matrix interfacial bonding was obtained in the laser-sintered structure. The 94.3% dense nanocomposites have a dynamic nanohardness of 3.47 GPa and a reduced elastic modulus of 613.42 GPa

  6. Grinding of WC-Co hard-metals

    NARCIS (Netherlands)

    Hegeman, J.B.J.W.; Hosson, de J.Th.M.; With, de G.

    2001-01-01

    Morphol. of ground surface of WC-Co cermets with 10 and 20% Co was studied. A deformed and detached surface layer was found on top of the specimens after surface grinding with a diamond wheel. Etching the surface layer revealed WC grains in the subsurface of the machined specimens. Most of these

  7. Physical Activity and Sedentary Behaviors Levels of Kuwaiti Adolescents: The Study of Health and Activity Among Adolescents in Kuwait.

    Science.gov (United States)

    Hashem, Rawan; Rey-López, Juan P; Hamer, Mark; McMunn, Anne; Whincup, Peter H; Owen, Christopher G; Rowlands, Alex; Stamatakis, Emmanuel

    2018-04-01

    There is only scarce number of studies available describing the lifestyle of adolescents living in Arab countries. Hence, we described physical activity (PA) and sedentary behaviors patterns among Kuwaiti adolescents and the associations with parental education. Cross-sectional data from 435 adolescents (201 boys and 234 girls) were collected from the Study of Health and Activity among Adolescents in Kuwait conducted between 2012 and 2013. Outcome variables included PA (ActiGraph GT1M accelerometers) and sedentary behaviors. Exposure variable was parental education. Descriptive and multiple logistic regression analyses were used to examine the association between parental education and outcome variables. Total sedentary time (minutes per day) was higher in girls [568.2 (111.6)] than in boys [500.0 (102.0)], whereas boys accumulated more minutes in light, moderate, and vigorous PA (all Ps ≤ .001). In total, 3.4% of adolescents spent ≥60 minutes per day of moderate to vigorous PA (by accelerometry), while only 21% met the screen time guidelines. Low/medium maternal education was associated with a higher odds of exceeding screen time guidelines (odds ratio = 2.09; 95% confidence interval, 1.09-4.02). Most Kuwaiti adolescents in this sample were physically inactive and exceeded screen time guidelines. Objective PA was not socially patterned, yet an inverse association between maternal education and screen time behaviors was found.

  8. Watching TV has a distinct sociodemographic and lifestyle profile compared with other sedentary behaviors: A nationwide population-based study.

    Science.gov (United States)

    Andrade-Gómez, Elena; García-Esquinas, Esther; Ortolá, Rosario; Martínez-Gómez, David; Rodríguez-Artalejo, Fernando

    2017-01-01

    Watching TV has been consistently associated with higher risk of adverse health outcomes, but the effect of other sedentary behaviors (SB) is uncertain. Potential explanations are that watching TV is not a marker of a broader sedentary pattern and that each SB reflects different sociodemographic and health characteristics. Data were taken form a survey on 10,199 individuals, representative of the Spanish population aged ≥18 years. SB and other health behaviors were ascertained using validated questionnaires. Watching TV was the predominant SB (45.4% of the total sitting time), followed by sitting at the computer (22.7%). TV watching time showed no correlation with total time on other SB (r: -0.02, p = 0.07). By contrast, time spent at the computer was directly correlated with time spent on commuting (r: 0.07, pmusic (r: 0.10, peducation, unhealthier lifestyle, and with diabetes or osteomuscular disease. More time spent at the computer or in commuting was linked to younger age, male gender, higher education and having a sedentary job. In conclusion, watching TV is not correlated with other SB and shows a distinct demographic and lifestyle profile.

  9. Sedentary lifestyle among adults in Jordan, 2007

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    Ghazi F. Sharkas

    2016-08-01

    Full Text Available Objective: Sedentary lifestyle is a major risk factor for physical and mental problems, such as cardiovascular, musculoskeletal diseases, and psychological stress. About 60% of the world’s population is not sufficiently physically active in leisure time or during work and social activities. This study aimed to determine the prevalence of inactive Jordanian adults and describe their demographic and behavioral characteristics. Methods: The study used data from the behavioral risk factors surveillance survey conducted in Jordan in 2007. The sample size was 3654. Respondents who were physically inactive for more than 240 min daily (sleep time not included were considered to have a sedentary lifestyle. Data were analyzed with the program SPSS. Results: The prevalence of a sedentary lifestyle was 82.8% (2965 respondents, with a mean sedentary time of 587 min (95% confidence interval 581–594 min. Among the physically inactive adults, 52.6% were men, one third of them aged 35–44 years. Sedentary lifestyle was reported by 30% of those with a secondary level of education or above. Of those with a sedentary lifestyle, 37.6% were housewives and 37.5% were employees; 66% of them were overweight and obese. Of the physically inactive people, 2.5% had a history of heart failure and 1.3% had a history of cerebrovascular accidents; 57.2% of them tried to engage more in physical activity and almost three quarters of them were interested in improving their dietary habits. Conclusion: Most Jordanian adults have a sedentary lifestyle, which emphasizes that there is a public health problem. Many of them are attempting to lead a healthier lifestyle. Therefore, there is an urgent need to launch an applicable national plan that enables people to practice a healthier lifestyle.

  10. Body mass index: accounting for full time sedentary occupation and 24-hr self-reported time use.

    Science.gov (United States)

    Tudor-Locke, Catrine; Schuna, John M; Katzmarzyk, Peter T; Liu, Wei; Hamrick, Karen S; Johnson, William D

    2014-01-01

    We used linked existing data from the 2006-2008 American Time Use Survey (ATUS), the Current Population Survey (CPS, a federal survey that provides on-going U.S. vital statistics, including employment rates) and self-reported body mass index (BMI) to answer: How does BMI vary across full time occupations dichotomized as sedentary/non-sedentary, accounting for time spent in sleep, other sedentary behaviors, and light, moderate, and vigorous intensity activities? We classified time spent engaged at a primary job (sedentary or non-sedentary), sleep, and other non-work, non-sleep intensity-defined behaviors, specifically, sedentary behavior, light, moderate, and vigorous intensity activities. Age groups were defined by 20-29, 30-39, 40-49, and 50-64 years. BMI groups were defined by 18.5-24.9, 25.0-27.4, 27.5-29.9, 30.0-34.9, and ≥35.0 kg/m2. Logistic and linear regression were used to examine the association between BMI and employment in a sedentary occupation, considering time spent in sleep, other non-work time spent in sedentary behaviors, and light, moderate, and vigorous intensity activities, sex, age race/ethnicity, and household income. The analysis data set comprised 4,092 non-pregnant, non-underweight individuals 20-64 years of age who also reported working more than 7 hours at their primary jobs on their designated time use reporting day. Logistic and linear regression analyses failed to reveal any associations between BMI and the sedentary/non-sedentary occupation dichotomy considering time spent in sleep, other non-work time spent in sedentary behaviors, and light, moderate, and vigorous intensity activities, sex, age, race/ethnicity, and household income. We found no evidence of a relationship between self-reported full time sedentary occupation classification and BMI after accounting for sex, age, race/ethnicity, and household income and 24-hours of time use including non-work related physical activity and sedentary behaviors. The various sources of

  11. The effects of a 2-year individualized and family-based lifestyle intervention on physical activity, sedentary behavior and diet in children.

    Science.gov (United States)

    Viitasalo, Anna; Eloranta, Aino-Maija; Lintu, Niina; Väistö, Juuso; Venäläinen, Taisa; Kiiskinen, Sanna; Karjalainen, Panu; Peltola, Jaana; Lampinen, Eeva-Kaarina; Haapala, Eero A; Paananen, Jussi; Schwab, Ursula; Lindi, Virpi; Lakka, Timo A

    2016-06-01

    To investigate the effects of a long-term, individualized and family-based lifestyle intervention on physical activity, sedentary behavior and diet quality in children. We carried out a 2-year intervention study in a population sample of 506 children aged 6-8years in Finland in 2007-2012. We allocated the participants at baseline in the intervention and control group. We assessed physical activity and sedentary behavior by questionnaires and diet by food records. Total physical activity (+9min/d in intervention group vs. -5min/d in control group, p=0.001 for time*group interaction), unsupervised physical activity (+7min/d vs. -9min/d, psedentary behavior and enhanced diet quality in children. ClinicalTrials.gov: NCT01803776. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Associations of Sedentary Behavior, Physical Activity, Cardiorespiratory Fitness, and Body Fat Content With Pain Conditions in Children: The Physical Activity and Nutrition in Children Study.

    Science.gov (United States)

    Vierola, Anu; Suominen, Anna Liisa; Lindi, Virpi; Viitasalo, Anna; Ikävalko, Tiina; Lintu, Niina; Väistö, Juuso; Kellokoski, Jari; Närhi, Matti; Lakka, Timo A

    2016-07-01

    We investigated the cross-sectional associations of sedentary behavior, physical activity, cardiorespiratory fitness, and body fat content with pain conditions in prepubertal children. The participants were a population sample of 439 children aged 6 to 8 years. Sedentary behavior, physical activity, and pain conditions were assessed using questionnaires, cardiorespiratory fitness using maximal cycle ergometer test, and body fat percentage using dual-energy X-ray absorptiometry. The associations of sedentary behavior, physical activity, cardiorespiratory fitness, and body fat percentage with the risk of pain conditions were analyzed using multivariate logistic regression. Children in the highest sex-specific third of sedentary behavior had 1.95 (95% confidence interval [CI], 1.20-3.17; P = .007 for trend across thirds) times higher odds of any pain than children in the lowest third. Children in the highest sex-specific third of cardiorespiratory fitness had 46% (odds ratio [OR] = .54; 95% CI, .32-.91; P = .019) lower odds of any pain and 50% (OR = .50; 95% CI, .28-.87; P = .015) lower odds of headache than children in the lowest third. Children in the highest sex-specific third of body fat percentage had 44% (OR = .56; 95% CI, .34-.93; P = .023) lower odds of any pain, 49% (OR = .51; 95% CI, .30-.86; P = .011) lower risk of multiple pain, and 48% (OR = .52; 95% CI, .31-.86; P = .010) lower odds of lower limb pain than children in the lowest third. Physical activity was not associated with pain conditions. These findings suggest that prepubertal children with high levels of sedentary behavior, low levels of cardiorespiratory fitness, and low body fat content have increased likelihood of various pain conditions. This information could be used to develop strategies to prevent chronic pain in childhood. Our findings suggest that low cardiorespiratory fitness, high levels of sedentary behavior, and low body fat content are associated with increased

  13. Associations of sedentary time and patterns of sedentary time accumulation with health-related quality of life in colorectal cancer survivors

    Directory of Open Access Journals (Sweden)

    Eline H. van Roekel

    2016-12-01

    Full Text Available Sedentary behavior (sitting/lying at low energy expenditure while awake is emerging as an important risk factor that may compromise the health-related quality of life (HRQoL of colorectal cancer (CRC survivors. We examined associations of sedentary time with HRQoL in CRC survivors, 2–10 years post-diagnosis. In a cross-sectional study, stage I–III CRC survivors (n = 145 diagnosed (2002−2010 at Maastricht University Medical Center+, the Netherlands, wore the thigh-mounted MOX activity monitor 24 h/day for seven consecutive days. HRQoL outcomes were assessed by validated questionnaires (EORTC QLQ-C30, WHODAS II, Checklist Individual Strength, and Hospital Anxiety and Depression Scale. Confounder-adjusted linear regression models were used to estimate associations with HRQoL outcomes of MOX-derived total and prolonged sedentary time (in prolonged sedentary bouts ≥30 min, and usual sedentary bout duration, corrected for waking wear time. On average, participants spent 10.2 h/day sedentary (SD, 1.6, and 4.5 h/day in prolonged sedentary time (2.3. Mean usual sedentary bout duration was 27.3 min (SD, 16.8. Greater total and prolonged sedentary time, and longer usual sedentary bout duration were associated with significantly (P < 0.05 lower physical functioning, and higher disability and fatigue scores. Greater prolonged sedentary time and longer usual sedentary bout duration also showed significant associations with lower global quality of life and role functioning. Associations with distress and social functioning were non-significant. Sedentary time was cross-sectionally associated with poorer HRQoL outcomes in CRC survivors. Prospective studies are needed to investigate whether sedentary time reduction is a potential target for lifestyle interventions aiming to improve the HRQoL of CRC survivors.

  14. Electrochemical properties of mixed WC and Pt-black powders

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    MAJA D. OBRADOVIC

    2008-12-01

    Full Text Available The electrochemical characteristics of a mixture of Pt-black and WC powders and its catalytic activity for methanol and formic acid oxidation were investigated in acid solution. XRD and AFM measurements revealed that the WC powder employed for the investigation was a single-phase material consisting of crystallites/spherical particles of average size of about 50 nm, which were agglomerated into much larger particles. Cyclic voltammetry showed that the WC underwent electrochemical oxidation, producing tungstate species. In the case of the mixed Pt + WC powders, the tungstate species were deposited on the Pt as a thin film of hydrous tungsten oxide. Enhanced hydrogen intercalation in the hydrous tungsten oxide was observed and it was proposed to be promoted in mixed powders by the presence of hydrogen adatoms on bare Pt sites. The determination of Pt surface area in the Pt + WC layer by stripping of underpotentially deposited Cu revealed that the entire Pt surface was accessible for underpotential deposition of Cu. Investigation of the electrochemical oxidation of methanol and formic acid on Pt + WC and pure Pt layers did not indicate electrocatalytic promotion due to the presence of WC.

  15. Prediction of bone mineral density and content from measures of physical activity and sedentary behavior in younger and older females

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    Saori I. Braun

    2015-01-01

    Conclusions: These findings highlight the importance of engaging in sufficient moderate-to-vigorous physical activity during adolescence and reducing sedentary behavior in older adults to improve bone health in females.

  16. Role of Vegetarian Diet in preventing diabetes in population practicing sedentary lifestyle: A case study in Eastern region of India

    Directory of Open Access Journals (Sweden)

    Ardhendu Bhusan Praharaj

    2017-10-01

    Full Text Available India in twenty-first century has seen a rapid transformation in dietary convention, with immoderate intake of calorie-rich food along with a sedentary lifestyle. The prevalence of type 2 diabetes (T2D is quite alarming and observed to be 1.6 to 2 times as high among non-vegetarians (NV compared to vegetarians. Dietary factors and physical activity are two major factors in T2D predisposition and disease management. Recent studies have shown that physical activity and vegetarian diets improve insulin sensitivity and glycemic control. The current investigation was carried out to observe the effect of diet in two Indian communities practicing sedentary lifestyle through a retrospective cross-sectional study. Depending on the lacto vegetarian diet (LV and non-vegetarian dietary patterns in individuals, the study population was divided into two groups. Two Indian communities namely Jain and Marwari as LV and Odia as NV those are residing in Bhubaneswar, Odisha were considered for this study. The survey was conducted from January 2015 to April 2015. A total of 403 participants (253 male and 150 female aged 30-80 years were enrolled in the study. Individuals undergoing medication for any known diseases, such as diabetes mellitus, rheumatoid arthritis, etc. including pregnant women or those with polycystic ovarian syndrome were also excluded from the study. Fasting blood samples were analyzed for blood sugar, glycated hemoglobin (HbA1C, and lipid profile. Body mass index (BMI and waist circumference (WC measurements were also recorded. The incidence of T2D was lower in lacto-vegetarian (1.7% than in NV group (5.3% despite similar lipid profiles and BMI/WC between these two groups. Fasting blood sugar (FBS was positively correlated with LDL and VLDL levels and negatively correlated with HDL, only in lacto-vegetarian group. The study ignited that although the sedentary lifestyle and fat-rich diet of the LV group had an effect on individual’s overall

  17. Higher cardiorespiratory and muscular fitness in males could not be attributed to physical activity, sports practice or sedentary behavior in young people

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    Diogo Henrique Constantino Coledam

    2018-03-01

    Full Text Available The purpose of the present study was to analyze if the association between sex with cardiorespiratory and muscular fitness is independent of physical activity, sports practice and sedentary behavior in young people. A cross-sectional study involving 729 participants aged 10 to 17 years. Physical activity, sports practice and sedentary behavior were assessed through a questionnaire. Cardiorespiratory fitness was measured using 20m shuttle run test and were analyzed: VO2max, number of laps and health-related criteria. Muscular fitness was assessed with 90o push-up test and number of repetition and health-related criteria was analyzed. Multiple linear regression was used to estimate β coeficients and Poisson regression estimated prevalence ratios (PR. Male sex was associated to higher cardiorespiratory fitness (VO2max β = 9.04 to 9.77, Laps PR=1.67 to 1.80, health-related criteria PR=2.03 to 2.09 and the same occurred with muscular fitness (repetitions PR=2.81 to 3.01, health-related criteria PR=1.91 to 2.09. Similarly, the stratification of the sample according to physical activity, sports practice and sedentary behavior did not change the associations between sex with cardiorespiratory (VO2max β=8.07 to 10.00, Laps PR=1.49 to 1.85, health-related criteria PR=1.64 to 2.27 and muscular fitness (repetitions PR=2.24 to 3.22, health-related criteria PR=1.76 to 2.06. These data suggest that higher cardiorespiratory and muscular fitness in males could not be attributed to physical activity, sports practice or sedentary behavior in young people.

  18. Obesity, Physical Activity and Sedentary Behavior Amongst British and Saudi Youth: A Cross-Cultural Study

    Directory of Open Access Journals (Sweden)

    Alan Nevill

    2012-04-01

    Full Text Available This study explores differences in weight status, obesity and patterns of physical activity (PA in relation to gender and age of youth from two culturally, environmentally and geographically diverse countries, the United Kingdom (UK and Saudi Arabia (SA. A total of 2,290 males and females (15–17 years volunteered to participate in this study. Participants completed a validated self-report questionnaire that contained 47 items relating to patterns of PA, sedentary activity and eating habits. The questionnaire allows the calculation of total energy expenditure in metabolic equivalent (MET-min values per week. Significant differences in percentage of overweight/obese and levels of PA were evident between the youth from the two countries, with males being generally more physically active than females. Additionally, there were significant associations between Body Mass Index (BMI, PA and sedentary behaviors; the youth with higher BMI reported lower levels of PA and higher amounts of sedentary time. These findings highlight the diverse nature of lifestyle of youth living in different geographical areas of the world and the need for further research to explore the socio-cultural factors that impact on the prevalence of obesity and patterns of PA of youth in different populations.

  19. Screen-based sedentary behavior, physical activity, and muscle strength in the English longitudinal study of ageing.

    Directory of Open Access Journals (Sweden)

    Mark Hamer

    Full Text Available Sarcopenia is associated with loss of independence and ill-health in the elderly although the causes remain poorly understood. We examined the association between two screen-based leisure time sedentary activities (daily TV viewing time and internet use and muscle strength.We studied 6228 men and women (aged 64.9 ± 9.1 yrs from wave 4 (2008-09 of the English Longitudinal Study of Ageing, a prospective study of community dwelling older adults. Muscle strength was assessed by a hand grip test and the time required to complete five chair rises. TV viewing and internet usage were inversely associated with one another. Participants viewing TV ≥ 6 hrs/d had lower grip strength (Men, B = -1.20 kg, 95% CI, -2.26, -0.14; Women, -0.75 kg, 95% CI, -1.48, -0.03 in comparison to <2 hrs/d TV, after adjustment for age, physical activity, smoking, alcohol, chronic disease, disability, depressive symptoms, social status, and body mass index. In contrast, internet use was associated with higher grip strength (Men, B = 2.43 kg, 95% CI, 1.74, 3.12; Women, 0.76 kg, 95% CI, 0.32, 1.20. These associations persisted after mutual adjustment for both types of sedentary behaviour.In older adults, the association between sedentary activities and physical function is context specific (TV viewing vs. computer use. Adverse effects of TV viewing might reflect the prolonged sedentary nature of this behavior.

  20. Psychometric Properties of a Scale to Assess Parental Self-Efficacy for Influencing Children's Dietary, Physical Activity, Sedentary, and Screen Time Behaviors in Disadvantaged Areas.

    Science.gov (United States)

    Norman, Åsa; Bohman, Benjamin; Nyberg, Gisela; Schäfer Elinder, Liselotte

    2018-02-01

    According to social cognitive theory, self-efficacy is central to behavior change. Consequently, parental self-efficacy (PSE) for influencing children's dietary, physical activity (PA), sedentary, and screen time behaviors is important for child obesity prevention. The aim of this study was to evaluate the psychometric properties of an instrument to measure PSE regarding these behaviors in disadvantaged areas. Parents ( n = 229) of whom 47% had completed secondary school or less, and who participated in the Healthy School Start trial, responded to a 15-item PSE instrument. Children's diet and screen time were measured through parent reports. PA and sedentary behaviors were measured using accelerometers. Construct validity was assessed using exploratory factor analysis (EFA), criterion validity by correlations with child behaviors, and internal consistency by Cronbach's alpha. The EFA yielded three factors: (a) PSE for promoting PA; (b) PSE for limiting intake of unhealthy foods, unhealthy drinks, and screen time; and (c) PSE for promoting intake of fruits and vegetables, all with acceptable to good internal consistency (α = .77-.81). Significant correlations ( p children's dietary ( r s = -.19 to -.29) and screen time ( r = -.29) behaviors and Factor 2, and dietary behaviors and Factor 3 ( r s = .20-.39) but not regarding PA and sedentary behaviors and Factor 1. The instrument demonstrated good construct validity and acceptable to good internal consistency regarding all but PA behaviors. It may be useful for assessing PSE in child obesity prevention interventions in disadvantaged settings after some refinement.

  1. Body mass index: accounting for full time sedentary occupation and 24-hr self-reported time use.

    Directory of Open Access Journals (Sweden)

    Catrine Tudor-Locke

    Full Text Available We used linked existing data from the 2006-2008 American Time Use Survey (ATUS, the Current Population Survey (CPS, a federal survey that provides on-going U.S. vital statistics, including employment rates and self-reported body mass index (BMI to answer: How does BMI vary across full time occupations dichotomized as sedentary/non-sedentary, accounting for time spent in sleep, other sedentary behaviors, and light, moderate, and vigorous intensity activities?We classified time spent engaged at a primary job (sedentary or non-sedentary, sleep, and other non-work, non-sleep intensity-defined behaviors, specifically, sedentary behavior, light, moderate, and vigorous intensity activities. Age groups were defined by 20-29, 30-39, 40-49, and 50-64 years. BMI groups were defined by 18.5-24.9, 25.0-27.4, 27.5-29.9, 30.0-34.9, and ≥35.0 kg/m2. Logistic and linear regression were used to examine the association between BMI and employment in a sedentary occupation, considering time spent in sleep, other non-work time spent in sedentary behaviors, and light, moderate, and vigorous intensity activities, sex, age race/ethnicity, and household income.The analysis data set comprised 4,092 non-pregnant, non-underweight individuals 20-64 years of age who also reported working more than 7 hours at their primary jobs on their designated time use reporting day. Logistic and linear regression analyses failed to reveal any associations between BMI and the sedentary/non-sedentary occupation dichotomy considering time spent in sleep, other non-work time spent in sedentary behaviors, and light, moderate, and vigorous intensity activities, sex, age, race/ethnicity, and household income.We found no evidence of a relationship between self-reported full time sedentary occupation classification and BMI after accounting for sex, age, race/ethnicity, and household income and 24-hours of time use including non-work related physical activity and sedentary behaviors. The various

  2. Physical activity, sedentary time, TV viewing, physical fitness and cardiovascular disease risk in adolescents: The HELENA study.

    Science.gov (United States)

    Barker, Alan R; Gracia-Marco, Luis; Ruiz, Jonatan R; Castillo, Manuel J; Aparicio-Ugarriza, Raquel; González-Gross, Marcela; Kafatos, Anthony; Androutsos, Odysseas; Polito, Angela; Molnar, Dénes; Widhalm, Kurt; Moreno, Luis A

    2018-03-01

    To examine the independent associations between physical activity (PA) intensities, sedentary time (ST), TV viewing, cardiorespiratory fitness (CRF) and muscular fitness (MF) with cardiovascular disease (CVD) risk in youth. A cross-sectional study on 534 European adolescents (252 males, 282 females, 12.5-17.5years). Minutes per day of light (LPA), moderate (MPA) and vigorous (VPA) PA and total ST were measured using accelerometers. TV viewing time was measured using a questionnaire. CRF and MF were measured using the 20m shuttle run test and a hand dynamometer respectively. CVD outcomes included markers of body composition (body mass index (BMI), waist circumference (WC), WC/height (Ht) and sum of skinfolds (SumSF)), blood pressure, blood lipids and insulin resistance (HOMA-IR). Clustered CVD risk was calculated using SumSF, HOMA-IR, blood lipids and blood pressure. LPA had a significant positive independent relationship with all body composition outcomes (P0.10). MPA had a negative independent relationship with only WC (P=0.029) and ST was not significantly related to CVD risk (P>0.16). TV viewing had a significant positive independent relationship with HOMA-IR (PTV viewing time to lower CVD risk in youth. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  3. Association of sedentary time with mortality independent of moderate to vigorous physical activity

    DEFF Research Database (Denmark)

    Koster, Annemarie; Caserotti, Paolo; Patel, Kushang V

    2012-01-01

    Sedentary behavior has emerged as a novel health risk factor independent of moderate to vigorous physical activity (MVPA). Previous studies have shown self-reported sedentary time to be associated with mortality; however, no studies have investigated the effect of objectively measured sedentary t...

  4. Accelerometer-measured sedentary time among Hispanic adults: Results from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL

    Directory of Open Access Journals (Sweden)

    Gina Merchant

    2015-01-01

    Full Text Available Excessive sedentary behavior is associated with negative health outcomes independent of physical activity. Objective estimates of time spent in sedentary behaviors are lacking among adults from diverse Hispanic/Latino backgrounds. The objective of this study was to describe accelerometer-assessed sedentary time in a large, representative sample of Hispanic/Latino adults living in the United States, and compare sedentary estimates by Hispanic/Latino background, sociodemographic characteristics and weight categories. This study utilized baseline data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL that included adults aged 18–74 years from four metropolitan areas (N = 16,415. Measured with the Actical accelerometer over 6 days, 76.9% (n = 12,631 of participants had >10 h/day and >3 days of data. Participants spent 11.9 h/day (SD 3.0, or 74% of their monitored time in sedentary behaviors. Adjusting for differences in wear time, adults of Mexican background were the least (11.6 h/day, whereas adults of Dominican background were the most (12.3 h/day, sedentary. Women were more sedentary than men, and older adults were more sedentary than younger adults. Household income was positively associated, whereas employment was negatively associated, with sedentary time. There were no differences in sedentary time by weight categories, marital status, or proxies of acculturation. To reduce sedentariness among these populations, future research should examine how the accumulation of various sedentary behaviors differs by background and region, and which sedentary behaviors are amenable to intervention.

  5. Sedentary Behavior among National Elite Rowers during Off-Training—A Pilot Study

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    Billy Sperlich

    2017-09-01

    Full Text Available The aim of this pilot study was to analyze the off-training physical activity (PA profile in national elite German U23 rowers during 31 days of their preparation period. The hours spent in each PA category (i.e., sedentary: <1.5 metabolic equivalents (MET; light physical activity: 1.5–3 MET; moderate physical activity: 3–6 MET and vigorous intense physical activity: >6 MET were calculated for every valid day (i.e., >480 min of wear time. The off-training PA during 21 weekdays and 10 weekend days of the final 11-week preparation period was assessed by the wrist-worn multisensory device Microsoft Band II (MSBII. A total of 11 rowers provided valid data (i.e., >480 min/day for 11.6 week days and 4.8 weekend days during the 31 days observation period. The average sedentary time was 11.63 ± 1.25 h per day during the week and 12.49 ± 1.10 h per day on the weekend, with a tendency to be higher on the weekend compared to weekdays (p = 0.06; d = 0.73. The average time in light, moderate and vigorous PA during the weekdays was 1.27 ± 1.15, 0.76 ± 0.37, 0.51 ± 0.44 h per day, and 0.67 ± 0.43, 0.59 ± 0.37, 0.53 ± 0.32 h per weekend day. Light physical activity was higher during weekdays compared to the weekend (p = 0.04; d = 0.69. Based on our pilot study of 11 national elite rowers we conclude that rowers display a considerable sedentary off-training behavior of more than 11.5 h/day.

  6. Reliability and validity of the Youth Leisure-time Sedentary Behavior Questionnaire (YLSBQ).

    Science.gov (United States)

    Cabanas-Sánchez, Verónica; Martínez-Gómez, David; Esteban-Cornejo, Irene; Castro-Piñero, José; Conde-Caveda, Julio; Veiga, Óscar L

    2018-01-01

    To develop a questionnaire able to assess time spent by youth in a wide range of leisure-time sedentary behaviors (SB) and evaluate its test-retest reliability and criterion validity. Cross-sectional observational. The reliability sample included 194 youth, aged 10-18 years, who completed the questionnaire twice, separated by one-week interval. The validity study comprised 1207 participants aged 8-18 years. Participants wore an accelerometer for 7 consecutive days. The questionnaire was designed to assess the amount of time spent in twelve different SB during weekdays and weekends, separately. In order to avoid usual phenomenon of time over reporting, values were adjusted to real available leisure-time (LT) for each participant. Reliability was assessed by using Intraclass Correlation Coefficients (ICC) and weighted (quadratic) kappa (k), and validity was assessed by using Pearson correlation and Bland-Altman plots. The reliability of questionnaire showed a moderate-to-substantial agreement for the most (91%) of items (k=0.43-0.74; ICC=0.41-0.79) with three items (4%) reaching an almost perfect agreement (ICC=0.82-0.83). Only 'sitting and talking' evidenced fair-to-moderate reliability (k=0.27-0.39; ICC=0.34-0.46). The relationship between average sedentary time assessed by the questionnaire and accelerometry was moderate (r=0.36; pquestionnaire and accelerometer sedentary time for average day (r=0.05; p=0.11) but Bland-Altman plots suggest moderate discrepancies between both methods of SB measurement (mean=19.86; limits of agreement=-280.04 to 319.76). The questionnaire showed moderate to good test-retest reliability and a moderate level of validity for assessing SB in youth, similar or slightly better to previously published in this population. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  7. Theoretical studies on the electronic and optoelectronic properties of [A.2AP(w)/A*.2AP(WC)/C.2AP(w)/C*.2AP(WC)/C.A(w)/C*.A(WC)]-Au8 mismatch nucleobase complexes

    Science.gov (United States)

    Srivastava, Ruby

    2018-01-01

    The electronic and optoelectronic properties of [A.2AP(w)/A*.2AP(WC)/C.2AP(w)/C*.2AP(WC)/C.A(w)/ C*.A(WC)]-Au8 metal-mismatch nucleobase complexes are investigated by means of density functional theory and time-dependent methods. We selected these mispairs as 2-aminopurine (2AP) produces incorporation errors when binding with cytosine (C) into the wobble (w) C.2AP(w) mispair, and is tautomerised into Watson-Crick (WC)-like base mispair C*.2AP(WC) and less effectively produces A.2AP(w)/A*.2AP(WC) mispairs. The vertical ionisation potential, vertical electron affinity, hardness and electrophilicity index of these complexes have also been discussed. The modifications of energy levels and charge density distributions of the frontier orbitals are also analysed. The absorption spectra of these complexes lie in the visible region, which suggests their application in fluorescent-bio imaging. The mechanism of cooperativity effect is studied by molecular orbital potential (MEP), atoms-in-molecules (AIM) and natural bond orbital analyses. Most metalated pairs have smaller HOMO-LUMO band gaps than the isolated mismatch nucleobases which suggest interesting consequences for electron transfer through DNA duplexes.

  8. Resource recovery of WC-Co cermet using hydrothermal oxidation technique

    International Nuclear Information System (INIS)

    Gao Ningfeng; Inagaki, F.; Sasai, R.; Itoh, H.; Watari, K.

    2005-01-01

    WC-Co cermet is widely used in industrial applications such as cutting tools, dies, wear parts and so on. It is of great importance to establish the recycling process for the precious metal resources contained in WC-Co cermet, because all these metals used in Japan are imported. In this paper we reported a hydrothermal oxidation technique using nitric acid for the reclamation of WC and Co. The WC-Co cermet specimens with various WC particle sizes and Co contents were hydrothermally treated in HNO 3 aqueous solutions at temperatures of 110-200 C for durations of 6-240 h. The Co was preferentially leached out into the acidic solution, while the WC was oxidized to insoluble WO 3 hydrate which was subsequently separated by filtration. The hydrothermal treatment parameters such as solvent concentrations, treatment temperatures, holding time were optimized in respect to different kinds of WC-Co cermets. A hydrothermal oxidation treatment in 3M HNO 3 aqueous solution at 150 C for 24 h was capable of fully disintegrating the cermet chip composed of coarse WC grains of 1-5 μm in size with 20 wt% of Co as binder. While the more oxidation resistant specimen composed of fine WC grains of 0.5-1.0 μm in size with 13 wt% of Co, was completely disintegrated by a treatment in 7 M HNO 3 aqueous solution at 170 C for 24 h. The filtered solid residues were composed of fine WO 3 .0.33H 2 O powder and a small amount of WO 3 . The recovered WO 3 .0.33H 2 O powder can be easily returned to the industrial process for the synthesis of WC powder so that the overall recycling cost can be possibly lowered. (orig.)

  9. Are Early Physical Activity and Sedentary Behaviors Related to Working Memory at 7 and 14 Years of Age?

    Science.gov (United States)

    López-Vicente, Mónica; Garcia-Aymerich, Judith; Torrent-Pallicer, Jaume; Forns, Joan; Ibarluzea, Jesús; Lertxundi, Nerea; González, Llúcia; Valera-Gran, Desirée; Torrent, Maties; Dadvand, Payam; Vrijheid, Martine; Sunyer, Jordi

    2017-09-01

    To evaluate the role of extracurricular physical activity and sedentary behavior at preschool and primary school age on working memory at primary school age and adolescence, respectively. This prospective study was based on a birth cohort across 4 Spanish regions. In the 3 younger subcohorts (n = 1093), parents reported lifestyle habits of child at age 4 years of age on a questionnaire, and children performed a computerized working memory task at 7 years of age. In the older subcohort (n = 307), the questionnaire was completed at 6 years of age and working memory was tested at 14 years of age. Adjusted regression models were developed to investigate the associations between lifestyle habits and working memory. Low extracurricular physical activity levels at 4 years of age were associated with a nonsignificant 0.95% (95% CI -2.81 to 0.92) reduction of correct responses in the working memory task at age 7 years of age. Low extracurricular physical activity levels at 6 years of age were associated with a 4.22% (95% CI -8.05 to -0.39) reduction of correct responses at age 14 years. Television watching was not associated with working memory. Other sedentary behaviors at 6 year of age were associated with a 5.07% (95% CI -9.68 to -0.46) reduction of correct responses in boys at 14 years of age. Low extracurricular physical activity levels at preschool and primary school ages were associated with poorer working memory performance at primary school age and adolescence, respectively. High sedentary behavior levels at primary school age were related negatively to working memory in adolescent boys. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Association of sedentary time with mortality independent of moderate to vigorous physical activity.

    Directory of Open Access Journals (Sweden)

    Annemarie Koster

    Full Text Available BACKGROUND: Sedentary behavior has emerged as a novel health risk factor independent of moderate to vigorous physical activity (MVPA. Previous studies have shown self-reported sedentary time to be associated with mortality; however, no studies have investigated the effect of objectively measured sedentary time on mortality independent of MVPA. The objective our study was to examine the association between objectively measured sedentary time and all-cause mortality. METHODS: 7-day accelerometry data of 1906 participants aged 50 and over from the U.S. nationally representative National Health and Nutrition Examination Survey (NHANES 2003-2004 were analyzed. All-cause mortality was assessed from the date of examination through December 31, 2006. RESULTS: Over an average follow-up of 2.8 years, there were 145 deaths reported. In a model adjusted for sociodemographic factors, lifestyle factors, multiple morbidities, mobility limitation, and MVPA, participants in third quartile (hazard ratio (HR:4.05; 95%CI:1.55-10.60 and fourth quartile (HR:5.94; 95%CI: 2.49-14.15 of having higher percent sedentary time had a significantly increased risk of death compared to those in the lowest quartile. CONCLUSIONS: Our study suggests that sedentary behavior is a risk factor for mortality independent of MVPA. Further investigation, including studies with longer follow-up, is needed to address the health consequences of sedentary behavior.

  11. The Association between Obesity and Symptoms of Psychopathology and its Relationship with Sedentary Behavior and Mediterranean Diet.

    Science.gov (United States)

    Dimitriadis, Dimitrios; Mamplekou, Efterpi; Dimitriadis, Panayiotis; Komessidou, Vasso; Dimitriadis, George; Papageorgiou, Charalambos

    2016-01-01

    Recent research indicates an association between obesity and symptoms of psychopathology, the nature of which remains obscure. This study examined the confounding role of behavioral factors on this association. One hundred and forty-two overweight/obese subjects who sought treatment for obesity, of both genders (51 males and 91 females), 18 to 64 years old and 139 normal-weight controls of both genders (41 males and 98 females), 18 to 63 years old, were enrolled in this study. We measured psychopathology features, using the Symptom Checklist 90-Revised (SCL-90-R), dietary habits, using the MedDietScore (MDS) questionnaire, and physical activity, using the International Physical Activity Questionnaire (IPAQ). A series of regression models were used to estimate the mediation of dietary patterns and physical activity on the obesity-psychopathology association. The associations between obesity and depression (β=0.32/β=0.15), obsession-compulsion (β=0.03/β=-0.13), anxiety (β=-0.25/β=-0.12), interpersonal sensitivity (β=0.08/β=-0.04) and psychoticism (β=-0.01/ β=0.025) are accounted for by sedentary behavior and Mediterranean diet. Our data suggest that modifiable behavioral factors such as sedentary time and dietary patterns positively affect the association between obesity and symptoms of psychopathology.

  12. Atomic layer deposition synthesis and evaluation of core–shell Pt-WC electrocatalysts

    International Nuclear Information System (INIS)

    Hsu, Irene J.; Chen, Jingguang G.; Jiang, Xiaoqiang; Willis, Brian G.

    2015-01-01

    Pt-WC core shell particles were produced using atomic layer deposition (ALD) to deposit Pt layers onto WC particle substrates. A range of Pt depositions were used to determine the growth mechanism for the Pt-WC powder system. TEM imaging and Cu stripping voltammetry found that Pt ALD growth on WC powder substrates was similar to that on WC thin films. However, excess free carbon was found to affect Pt ALD by blocking adsorption sites on WC. The Pt-WC samples were evaluated for the oxygen reduction reaction using a rotating disk electrode to obtain quantitative activity information. The mass and specific activities for the 30 and 50 ALD cycle samples were found to be comparable to a 10 wt. % Pt/C catalyst. However, higher overpotentials and lower limiting currents were observed with ALD Pt-WC compared to Pt/C catalysts, indicating that the oxygen reduction mechanism is not as efficient on Pt-WC as on bulk Pt. Additionally, these Pt-WC catalysts were used to demonstrate hydrogen evolution reaction activity and were found to perform as well as bulk Pt catalyst but with a fraction of the Pt loading, in agreement with the previous work on Pt-WC thin film catalysts

  13. Motivators and Barriers to Reducing Sedentary Behavior Among Overweight and Obese Older Adults.

    Science.gov (United States)

    Greenwood-Hickman, Mikael Anne; Renz, Anne; Rosenberg, Dori E

    2016-08-01

    To explore individual, social, environmental, and program-related motivators, barriers, and impacts of sedentary behavior (SB) reduction among a group of overweight and obese older adults aged 60 and older. Semistructured interviews were conducted with 24 participants following a SB reduction intervention. Transcripts from these interviews were iteratively coded by a team, and key themes were defined and refined guided by the social-ecological framework. Motivators included the desire to improve health, newly acquired awareness of SB, the ease of incorporating SB reduction into current lifestyle, an adaptable environment, and the use of reminders. Barriers included existing health conditions, enjoyment of sedentary activities, unadaptable environments, fatigue, and difficulty understanding SB reduction as distinct from physical activity (PA). Participants reported impacts on physical and mental health and changes in awareness, exercise, and daily activity. Although in many ways motivators and barriers to reducing SB are similar to those of PA, SB interventions have special considerations and may ultimately be easier for some individuals to incorporate into their lifestyle. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Physical Activity and Pediatric Obesity

    DEFF Research Database (Denmark)

    Mitchell, Jonathan A.; Dowda, Marsha; Pate, Russell R.

    2017-01-01

    Purpose We aimed to determine whether moderate to vigorous physical activity (MVPA) and sedentary behavior (SB) were independently associated with body mass index (BMI) and waist circumference (WC) in children and adolescents. Methods Data from the International Children's Accelerometry Database...

  15. Applying a Socioecological Model to Understand Preschool Children's Sedentary Behaviors from the Viewpoints of Parents and Preschool Personnel

    Science.gov (United States)

    Määttä, Suvi; Ray, Carola; Roos, Gun; Roos, Eva

    2016-01-01

    This study explored parents' and preschool personnel's opinions on factors influencing 3-5-year-old children's sedentary behaviors by applying the socioecological model. Four focus group interviews with preschool personnel (N = 14) and six interviews with parents (N = 17) were conducted in autumn 2014. Two researchers independently analyzed the…

  16. The home physical environment and its relationship with physical activity and sedentary behavior: a systematic review.

    Science.gov (United States)

    Kaushal, Navin; Rhodes, Ryan E

    2014-10-01

    Reviews of neighborhood (macro) environment characteristics such as the presence of sidewalks and esthetics have shown significant correlations with resident physical activity (PA) and sedentary (SD) behavior. Currently, no comprehensive review has appraised and collected available evidence on the home (micro) physical environment. The purpose of this review was to examine how the home physical environment relates to adult and child PA and SD behaviors. Articles were searched during May 2014 using Medline, PsycINFO, PubMed, Scopus, and SPORTDiscus databases which yielded 3265 potential studies. Papers were considered eligible if they investigated the presence of PA (ie. exercise equipment, exergaming devices) or SD (ie. television, videogames) equipment and PA or SD behavior. After, screening and manual cross-referencing, 49 studies (20 experimental and 29 observational designs) were found to meet the eligibility criteria. Interventions that reduced sedentary time by using TV limiting devices were shown to be effective for children but the results were limited for adults. Overall, large exercise equipment (ie. treadmills), and prominent exergaming materials (exergaming bike, dance mats) were found to be more effective than smaller devices. Observational studies revealed that location and quantity of televisions correlated with SD behavior with the latter having a greater effect on girls. This was similarly found for the quantity of PA equipment which also correlated with behavior in females. Given the large market for exercise equipment, videos and exergaming, the limited work performed on its effectiveness in homes is alarming. Future research should focus on developing stronger randomized controlled trials, investigate the location of PA equipment, and examine mediators of the gender discrepancy found in contemporary studies. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Metabolic Profiling of Total Physical Activity and Sedentary Behavior in Community-Dwelling Men.

    Directory of Open Access Journals (Sweden)

    Kota Fukai

    Full Text Available Physical activity is known to be preventive against various non-communicable diseases. We investigated the relationship between daily physical activity level and plasma metabolites using a targeted metabolomics approach in a population-based study.A total of 1,193 participants (male, aged 35 to 74 years with fasting blood samples were selected from the baseline survey of a cohort study. Information on daily total physical activity, classified into four levels by quartile of metabolic equivalent scores, and sedentary behavior, defined as hours of sitting per day, was collected through a self-administered questionnaire. Plasma metabolite concentrations were quantified by capillary electrophoresis mass spectrometry method. We performed linear regression analysis models with multivariable adjustment and corrected p-values for multiple testing in the original population (n = 808. The robustness of the results was confirmed by replication analysis in a separate population (n = 385 created by random allocation.Higher levels of total physical activity were associated with various metabolite concentrations, including lower concentrations of amino acids and their derivatives, and higher concentrations of pipecolate (FDR p <0.05 in original population. The findings persisted after adjustment for age, body mass index, smoking, alcohol intake, and energy intake. Isoleucine, leucine, valine, 4-methyl-2-oxoisopentanoate, 2-oxoisopentanoate, alanine, and proline concentrations were lower with a shorter sitting time.Physical activity is related to various plasma metabolites, including known biomarkers for future insulin resistance or type 2 diabetes. These metabolites might potentially play a key role in the protective effects of higher physical activity and/or less sedentary behavior on non-communicable diseases.

  18. The Association of Dietary Behaviors and Physical Activity Levels with General and Central Obesity among ASEAN University Students.

    Science.gov (United States)

    Peltzer, Karl; Pengpid, Supa

    2017-01-01

    To quantify the prevalence of obesity and obesity-related factors (dietary behaviors and physical activity levels) in a cross-sectional, observational study of ASEAN undergraduate students. A total of 6783 (35.5% male and 64.5% female) undergraduate students (Mean age: 20.5, SD = 2.0) from eight ASEAN countries completed questionnaires and anthropometric measurements. Multivariable logistic regression was used to estimate odds ratios (ORs) for the association of nutrition behaviors with prevalence of general obesity (body mass index ≥ 25 kg/m 2 ), elevated waist-to-height ratio (WHtR) (>0.50), and high waist circumference (WC) (≥80 cm in females, ≥90 cm in males). Covariates included sociodemographic factors, dietary behavior, physical activity and sitting time (using the "International Physical Activity Questionnaire"). There was a higher prevalence of general obesity (24.2% versus 9.3%), and high WHtR (16.6% versus 12.1) in males relative to females, while high WC (9.4% versus 10.4%) did not significantly differ between genders. In multivariable logistic regression analyses, compared to females, males had higher odds of obesity (odds-ratio, OR: 2.13, confidence interval, CI: 1.80, 2.77), and high WHtR (OR: 1.90, CI: 1.48, 2.43) ( P ASEAN young adults. Specific dietary behaviors but not physical activity nor sedentary behavior were associated with obesity.

  19. Reducing Recreational Sedentary Screen Time: A Community Guide Systematic Review.

    Science.gov (United States)

    Ramsey Buchanan, Leigh; Rooks-Peck, Cherie R; Finnie, Ramona K C; Wethington, Holly R; Jacob, Verughese; Fulton, Janet E; Johnson, Donna B; Kahwati, Leila C; Pratt, Charlotte A; Ramirez, Gilbert; Mercer, Shawna L; Glanz, Karen

    2016-03-01

    Sedentary time spent with screen media is associated with obesity among children and adults. Obesity has potentially serious health consequences, such as heart disease and diabetes. This Community Guide systematic review examined the effectiveness and economic efficiency of behavioral interventions aimed at reducing recreational (i.e., neither school- nor work-related) sedentary screen time, as measured by screen time, physical activity, diet, and weight-related outcomes. For this review, an earlier ("original") review (search period, 1966 through July 2007) was combined with updated evidence (search period, April 2007 through June 2013) to assess effectiveness of behavioral interventions aimed at reducing recreational sedentary screen time. Existing Community Guide systematic review methods were used. Analyses were conducted in 2013-2014. The review included 49 studies. Two types of behavioral interventions were evaluated that either (1) focus on reducing recreational sedentary screen time only (12 studies); or (2) focus equally on reducing recreational sedentary screen time and improving physical activity or diet (37 studies). Most studies targeted children aged ≤13 years. Children's composite screen time (TV viewing plus other forms of recreational sedentary screen time) decreased 26.4 (interquartile interval= -74.4, -12.0) minutes/day and obesity prevalence decreased 2.3 (interquartile interval= -4.5, -1.2) percentage points versus a comparison group. Improvements in physical activity and diet were reported. Three study arms among adults found composite screen time decreased by 130.2 minutes/day. Among children, these interventions demonstrated reduced screen time, increased physical activity, and improved diet- and weight-related outcomes. More research is needed among adolescents and adults. Published by Elsevier Inc.

  20. Associations of Total and Domain-Specific Sedentary Time With Type 2 Diabetes in Taiwanese Older Adults

    Directory of Open Access Journals (Sweden)

    Ming-Chun Hsueh

    2016-07-01

    Full Text Available Background: The increasing prevalence of type 2 diabetes in older adults has become a public health concern. We investigated the associations of total and domain-specific sedentary time with risk of type 2 diabetes in older adults. Methods: The sample comprised 1046 older people (aged ≥65 years. Analyses were performed using crosssectional data collected via computer-assisted telephone-based interviews in 2014. Data on six self-reported domains of sedentary time (Measure of Older Adults’ Sedentary Time, type 2 diabetes status, and sociodemographic variables were included in the study. Binary logistic regression analysis was performed to calculate the adjusted odds ratios (ORs and 95% confidence intervals (CIs for total and individual sedentary behavior components and likelihood of type 2 diabetes. Results: A total of 17.5% of the participants reported type 2 diabetes. No significant associations were found between total sitting time and risk of type 2 diabetes, after controlling for confounding factors. After total sedentary behavior was stratified into six domains, only watching television for more than 2 hours per day was associated with higher odds of type 2 diabetes (OR 1.56; 95% CI, 1.10–2.21, but no significant associations were found between other domains of sedentary behavior (computer use, reading, socializing, transport, and hobbies and risk of type 2 diabetes. Conclusions: These findings suggest that, among domain-specific sedentary behavior, excessive television viewing might increase the risk of type 2 diabetes among older adults more than other forms of sedentary behavior.

  1. Sedentary patterns, physical activity and health-related physical fitness in youth: a cross-sectional study.

    Science.gov (United States)

    Júdice, Pedro B; Silva, Analiza M; Berria, Juliane; Petroski, Edio L; Ekelund, Ulf; Sardinha, Luís B

    2017-03-04

    Strong evidence indicates that moderate-vigorous physical activity (MVPA) is positively associated with fitness in youth, independent of total sedentary-time. Sedentary-time appears negatively associated with fitness only when it replaces MVPA. However, whether different sedentary-patterns affect health-related fitness is unknown. The associations between MVPA and sedentary-patterns with physical fitness were examined in 2698 youths (1262 boys) aged 13.4 ± 2.28 years. Sedentary-time (counts · minute -1  Positive associations between MVPA and fitness were observed in both boys (β = 0.013, 95% CI: 0.005; 0.021) and girls (β = 0.014, 95% CI: 0.006; 0.022), independent of sedentary-patterns. Modest associations were found for the breaks in sedentary-time with fitness (β = 0.026, 95% CI: 0.009; 0.042), independent of total sedentary-time and MVPA in boys. In girls, non-prolonged sedentary bouts were positively associated with fitness (β = 0.014, 95% CI: 0.003; 0.024), independent of total sedentary-time and MVPA. These results reinforce that, independent of the time and patterns of sedentary behavior, MVPA is consistently associated with fitness in youth. Modest and inconsistent associations were found for sedentary behaviors. Breaking-up sedentary-time in boys and non-prolonged sedentary bouts in girls were positively associated with fitness, independent of total sedentary-time and MVPA. In order to enhance youth's fitness, public health recommendations should primarily target MVPA, still, suggestion to reduce and break-up sedentary-time may also be considered.

  2. Associations of Parental Rules and Socioeconomic Position With Preschool Children's Sedentary Behaviour and Screen Time.

    Science.gov (United States)

    Downing, Katherine L; Hinkley, Trina; Hesketh, Kylie D

    2015-04-01

    There is little current understanding of the influences on sedentary behavior and screen time in preschool children. This study investigated socioeconomic position (SEP) and parental rules as potential correlates of preschool children's sedentary behavior and screen time. Data from the Healthy Active Preschool Years (HAPPY) Study were used. Participating parents reported their child's usual weekly screen time and their rules to regulate their child's screen time. Children wore accelerometers for 8 days to objectively measure sedentary time. Children whose parents limited television viewing spent significantly less time in that behavior and in total screen time; however, overall sedentary behavior was unaffected. An association between parents limiting computer/electronic game use and time spent on the computer was found for girls only. SEP was inversely associated with girls', but not boys', total screen time and television viewing. As parental rules were generally associated with lower levels of screen time, intervention strategies could potentially encourage parents to set limits on, and switch off, screen devices. Intervention strategies should target preschool children across all SEP areas, as there was no difference by SEP in overall sedentary behavior or screen time for boys.

  3. Watching TV has a distinct sociodemographic and lifestyle profile compared with other sedentary behaviors: A nationwide population-based study.

    Directory of Open Access Journals (Sweden)

    Elena Andrade-Gómez

    Full Text Available Watching TV has been consistently associated with higher risk of adverse health outcomes, but the effect of other sedentary behaviors (SB is uncertain. Potential explanations are that watching TV is not a marker of a broader sedentary pattern and that each SB reflects different sociodemographic and health characteristics. Data were taken form a survey on 10,199 individuals, representative of the Spanish population aged ≥18 years. SB and other health behaviors were ascertained using validated questionnaires. Watching TV was the predominant SB (45.4% of the total sitting time, followed by sitting at the computer (22.7%. TV watching time showed no correlation with total time on other SB (r: -0.02, p = 0.07. By contrast, time spent at the computer was directly correlated with time spent on commuting (r: 0.07, p<0.01, listening to music (r: 0.10, p<0.01 and reading (r: 0.08, p<0.01. TV watching time was greater in those with older age, lower education, unhealthier lifestyle, and with diabetes or osteomuscular disease. More time spent at the computer or in commuting was linked to younger age, male gender, higher education and having a sedentary job. In conclusion, watching TV is not correlated with other SB and shows a distinct demographic and lifestyle profile.

  4. A National Survey of Physical Activity and Sedentary Behavior of Chinese City Children and Youth Using Accelerometers

    Science.gov (United States)

    Wang, Chao; Chen, Peijie; Zhuang, Jie

    2013-01-01

    Purpose: The purpose of this study was to objectively assess levels of physical activity (PA) and sedentary behavior (SB) of Chinese city children and youth aged 9 to 17 years old using accelerometers and to examine their differences by gender, age, grade, and weight status. Method: The PA and SB of 2,163 students in 4th grade through 11th grade…

  5. Bidirectional associations between activity-related parenting practices, and child physical activity, sedentary screen-based behavior and body mass index: a longitudinal analysis

    OpenAIRE

    Sleddens, Ester F. C.; Gubbels, Jessica S.; Kremers, Stef P. J.; van der Plas, Eline; Thijs, Carel

    2017-01-01

    Background It has been generally assumed that activity-related parenting practices influence children?s activity behavior and weight status. However, vice versa parents may also change their parenting behaviors in response to their perceptions of their child?s activity behavior and weight status. This study examined the bidirectional relationships between activity-related parenting practices, and physical activity, sedentary screen-based behavior, and body mass index (BMI) between children?s ...

  6. The Nature of Bonding in WC and WN

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The nature of bonding in the title compounds has been studied by using CASSCF and FOCl techniques. The ground states of WC and WN are found to be 3Δ and 4∑- state arising primarily from:...1σ2σ21π41δ13σ1 and ...1σ2σ21π41δ23σ1 configuration respectively. WC shows a strong character of covalent bond while WN have obvious character of ionic bond and the dissociation energy of WN is larger than that of WC (6.15 and 5.41 eV respective).

  7. Brief scales to assess physical activity and sedentary equipment in the home

    Directory of Open Access Journals (Sweden)

    Durant Nefertiti

    2010-01-01

    Full Text Available Abstract Background Sedentary behaviors such as TV viewing are associated with childhood obesity, while physical activity promotes healthy weight. The role of the home environment in shaping these behaviors among youth is poorly understood. The study purpose was to examine the reliability of brief parental proxy-report and adolescent self-report measures of electronic equipment and physical activity equipment in the home and to assess the construct validity of these scales by examining their relationship to physical activity, sedentary behavior, and weight status of children and adolescents. Methods Participants were adolescents (n = 189; mean age = 14.6, parents of adolescents (n = 171; mean age = 45.0, and parents of younger children (n = 116; parents mean age = 39.6; children's mean age = 8.3 who completed two surveys approximately one month apart. Measures included a 21-item electronic equipment scale (to assess sedentary behavior facilitators in the home, in the child or adolescent's bedroom, and portable electronics and a 14-item home physical activity equipment scale. Home environment factors were examined as correlates of children's and adolescents' physical activity, sedentary behavior, and weight status after adjusting for child age, sex, race/ethnicity, household income, and number of children in the home. Results Most scales had acceptable test-retest reliability (intraclass correlations were .54 - .92. Parent and adolescent reports were correlated. Electronic equipment in adolescents' bedrooms was positively related to sedentary behavior. Activity equipment in the home was inversely associated with television time in adolescents and children, and positively correlated with adolescents' physical activity. Children's BMI z-score was positively associated with having a television in their bedroom. Conclusions The measures of home electronic equipment and activity equipment were similarly reliable when reported by parents and by

  8. Genotype by sex and genotype by age interactions with sedentary behavior: the Portuguese Healthy Family Study.

    Directory of Open Access Journals (Sweden)

    Daniel M V Santos

    Full Text Available Sedentary behavior (SB expression and its underlying causal factors have been progressively studied, as it is a major determinant of decreased health quality. In the present study we applied Genotype x Age (GxAge and Genotype x Sex (GxSex interaction methods to determine if the phenotypic expression of different SB traits is influenced by an interaction between genetic architecture and both age and sex. A total of 1345 subjects, comprising 249 fathers, 327 mothers, 334 sons and 325 daughters, from 339 families of The Portuguese Healthy Family Study were included in the analysis. SB traits were assessed by means of a 3-d physical activity recall, the Baecke and IPAQ questionnaires. GxAge and GxSex interactions were analyzed using SOLAR 4.0 software. Sedentary behaviour heritability estimates were not always statistically significant (p>0.05 and ranged from 3% to 27%. The GxSex and GxAge interaction models were significantly better than the single polygenic models for TV (min/day, EEsed (kcal/day, personal computer (PC usage and physical activty (PA tertiles. The GxAge model is also significantly better than the polygenic model for Sed (min/day. For EEsed, PA tertiles, PC and Sed, the GxAge interaction was significant because the genetic correlation between SB environments was significantly different from 1. Further, PC and Sed variance heterogeneity among distinct ages were observed. The GxSex interaction was significant for EEsed due to genetic variance heterogeneity between genders and for PC due to a genetic correlation less than 1 across both sexes. Our results suggest that SB expression may be influenced by the interactions between genotype with both sex and age. Further, different sedentary behaviors seem to have distinct genetic architectures and are differentially affected by age and sex.

  9. Correlates of objectively measured sedentary behavior in cancer patients with brain metastases: an application of the theory of planned behavior.

    Science.gov (United States)

    Lowe, Sonya S; Danielson, Brita; Beaumont, Crystal; Watanabe, Sharon M; Baracos, Vickie E; Courneya, Kerry S

    2015-07-01

    The aim of this study is to examine the demographic, medical, and social-cognitive correlates of objectively measured sedentary behavior in advanced cancer patients with brain metastases. Advanced cancer patients diagnosed with brain metastases, aged 18 years or older, cognitively intact, and with palliative performance scale greater than 30%, were recruited from a Rapid Access Palliative Radiotherapy Program multidisciplinary brain metastases clinic. A cross-sectional survey interview assessed the theory of planned behavior variables and medical and demographic information. Participants wore activPAL™ (PAL Technologies Ltd, Glasgow, United Kingdom) accelerometers recording time spent supine, sitting, standing, and stepping during 7 days encompassing palliative whole brain radiotherapy treatments. Thirty-one patients were recruited. Correlates of median time spent supine or sitting in hours per day were instrumental attitude (i.e., perceived benefits) of physical activity (r = -0.42; p = 0.030) and affective attitude (i.e., perceived enjoyment) of physical activity (r = -0.43; p = 0.024). Moreover, participants who sat or were supine for greater than 20.7 h per day reported significantly lower instrumental attitude (M = 0.7; 95% CI = 0.0-1.4; p = 0.051) and affective attitude (M = 0.7; 95% CI = 0.0-1.4; p = 0.041). Finally, participants who were older than 60 years of age spent more time sitting or being supine. Instrumental attitude and affective attitude were the strongest correlates of objectively measured sedentary behavior. This information could inform intervention studies to increase physical activity in advanced cancer patients with brain metastases. Copyright © 2014 John Wiley & Sons, Ltd.

  10. Influence of physical activity, sedentary behavior, and diet quality in childhood on the incidence of internalizing and externalizing disorders during adolescence: a population-based cohort study.

    Science.gov (United States)

    Wu, XiuYun; Bastian, Kerry; Ohinmaa, Arto; Veugelers, Paul

    2018-02-01

    Studies among youth suggest that physical inactivity, sedentary behaviors, and poor diet quality are associated with poor mental health. Few population-based studies have investigated these relationships longitudinally. We examined the association between physical activity, sedentary behaviors, and diet quality in childhood and the incidence of internalizing and externalizing disorders throughout adolescence. We linked health behavior survey data from 2003 among 10- to 11-year-old children across Nova Scotia, Canada, with administrative health care data from 2003 to 2011. Students' diet quality was assessed using the Harvard Food Frequency Questionnaire. Physical activity and sedentary behaviors were self-reported, and internalizing and externalizing disorders were diagnosed by a physician. We applied Cox regression to examine the associations of the health behaviors with the incidence of internalizing and externalizing disorders between 2003 and 2011. Of the 4861 participating students, 23.7% and 9.4% had a diagnosis of internalizing and externalizing disorders, respectively. The incidences of internalizing and externalizing disorders were higher among students who were less physically active and spent more time using computers and video games. These findings suggest that promoting an active lifestyle in childhood may contribute to the prevention of both internalizing and externalizing disorders during adolescence. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Reactive Sintering of Bimodal WC-Co Hardmetals

    Directory of Open Access Journals (Sweden)

    Marek Tarraste

    2015-09-01

    Full Text Available Bimodal WC-Co hardmetals were produced using novel technology - reactive sintering. Milled and activated tungsten and graphite powders were mixed with commercial coarse grained WC-Co powder and then sintered. The microstructure of produced materials was free of defects and consisted of evenly distributed coarse and fine tungsten carbide grains in cobalt binder. The microstructure, hardness and fracture toughness of reactive sintered bimodal WC-Co hardmetals is exhibited. Developed bimodal hardmetal has perspective for demanding wear applications for its increased combined hardness and toughness. Compared to coarse material there is only slight decrease in fracture toughness (K1c is 14.7 for coarse grained and 14.4 for bimodal, hardness is increased from 1290 to 1350 HV units.DOI: http://dx.doi.org/10.5755/j01.ms.21.3.7511

  12. WC-3015 alloy (high-temperature alloy)

    International Nuclear Information System (INIS)

    Anon.

    1974-01-01

    WC-3015 Nb alloy containing 28 to 30 Hf, 1 to 2 Zr, 13 to 16 W, 0 to 4 Ta, 0 to 5 Ti, 0.07 to 0.33 C, less than or equal to 0.02 N, less than or equal to 0.03 O, less than or equal to 0.001 H was developed for use at high temperature in oxidizing environments. Its composition can be tailored to meet specific requirements. When WC-3015 is exposed to O at elevated temperature, Hf and Nb oxidized preferentially and HfO 2 dissolves in Nb 2 O 5 to form 6HfO-Nb 2 O 5 . This complex oxide has a tight cubic lattice which resists the diffusion of O into the substrate. During 24-h exposure to air at 2400 0 F, the alloy oxidizes to a depth of approximately 0.035 in. with a surface recession of 0 to 0.004 in. Oxidation resistance of WC-3015 welds and base material can be further enhanced greatly by applying silicide coatings. WC-3015 alloy can be machined by conventional and electrical-discharge methods. It can be hot worked readily by extrusion, forging or rolling. Cold working can be used at room or elevated temperature. It can be welded by the electron-beam or Tig processes. Physical constants, typical mechanical properties at 75 to 2400 0 F, and effects of composition and heat treatment on tensile and stress-rupture properties of the alloy are tabulated

  13. Beyond recreational physical activity: examining occupational and household activity, transportation activity, and sedentary behavior in relation to postmenopausal breast cancer risk.

    Science.gov (United States)

    George, Stephanie M; Irwin, Melinda L; Matthews, Charles E; Mayne, Susan T; Gail, Mitchell H; Moore, Steven C; Albanes, Demetrius; Ballard-Barbash, Rachel; Hollenbeck, Albert R; Schatzkin, Arthur; Leitzmann, Michael F

    2010-11-01

    We prospectively examined nonrecreational physical activity and sedentary behavior in relation to breast cancer risk among 97 039 postmenopausal women in the National Institutes of Health-AARP Diet and Health Study. We identified 2866 invasive and 570 in situ breast cancer cases recorded between 1996 and 2003 and used Cox proportional hazards regression to estimate multivariate relative risks (RRs) and 95% confidence intervals (CIs). Routine activity during the day at work or at home that included heavy lifting or carrying versus mostly sitting was associated with reduced risk of invasive breast cancer (RR = 0.62; 95% CI = 0.42, 0.91; P(trend) = .024). Routine activity during the day at work or home may be related to reduced invasive breast cancer risk. Domains outside of recreation time may be attractive targets for increasing physical activity and reducing sedentary behavior among postmenopausal women.

  14. Physical activity, sedentary behavior, and body mass index in the Czech Republic: a nationally representative survey.

    Science.gov (United States)

    Mitáš, Josef; Ding, Ding; Frömel, Karel; Kerr, Jacqueline

    2014-07-01

    Post-communist countries have experienced rapid economic development and social changes, which have been accompanied by changes in health-related lifestyle behaviors, such as physical activity. The purpose of this study was to examine the associations of domain-specific physical activity and total sedentary time with BMI among adults in the Czech Republic. We surveyed a nationally representative sample (n = 4097) of the Czech Republic in fall 2007 using the International Physical Activity Questionnaire (long form). Multiple linear regression analyses were used to examine associations of physical activity, sedentary time and sociodemographic characteristics with BMI. Older age, lower educational attainment, and lower levels of leisure-time physical activity were associated with higher BMI. Compared with those living in large cities, men living in small towns and women living in small villages had higher BMI. This study has identified correlates of BMI in the Czech Republic. Although more evidence from longitudinal studies is needed, findings from the current study can inform interventions to prevent the rising obesity epidemic.

  15. Decreasing Sedentary Behavior: Effects on Academic Performance, Meta-Cognition, and Sleep.

    Science.gov (United States)

    Pilcher, June J; Morris, Drew M; Bryant, Stewart A; Merritt, Paul A; Feigl, Hayley B

    2017-01-01

    There is growing interest in using activity workstations as a method of increasing light physical activity in normally sedentary environments. The current study ( N = 117) compared the effects of studying in college students while slowly pedaling a stationary bike with a desktop with studying at traditional desks across 10 weeks in an academic semester. The students were assigned to study either on the stationary bike or at a traditional desk located in the campus library for a minimum of 2 h a week. During the 10 weeks, the students studied for tests or worked on other required academic activities while working at their assigned desk. In addition, the participants completed a pre survey, weekly surveys, and a post survey. We found that although students studying at the traditional desks reported more ease of studying and more effective studying than those using the stationary bikes, the two groups performed equally well on tests in an introductory psychology course. Moreover, the students using the traditional desks reported a decrease in sleep quality later in the semester while those using the activity workstation reported stable levels of sleep quality. The current results indicate that activity workstations could be implemented in university settings to encourage light physical activity without negatively affecting academic performance while providing possible long-term health and well-being benefits. Furthermore, the results suggests that activity workstations could be a means of combating sedentary behavior in environments where individuals are expected to sit either while waiting (e.g., doctor's waiting rooms, airports) or when completing a necessary task (e.g., the workplace, educational settings).

  16. Obesity, Dietary Habits, and Sedentary Behaviors Among Adolescents in Sudan: Alarming Risk Factors for Chronic Diseases in a Poor Country.

    Science.gov (United States)

    Musaiger, Abdulrahman O; Nabag, Fatima O; Al-Mannai, Mariam

    2016-03-01

    The aim of this study was to investigate the prevalence of obesity, dietary habits, and sedentary patterns among Sudanese adolescents. A multistage stratified sampling method was used to select 945 adolescents (507 males and 438 females) aged 14 to 18 years, from Khartoum State, Sudan. A self-reported pretested questionnaire was used to collect the data. Overweight and obesity were determined using the International Obesity Task Force standard, which is based on body mass index for sex and age. Overweight and obesity were growing problems among urban Sudanese adolescents (10.7%). Breakfast was commonly consumed on a daily basis by the majority of adolescents (74.2%), followed by lunch (63.9%) and supper (33.5%). Snacking was not a common practice among these individuals. Vegetables (63.9%) were more frequently consumed (more than 3 days per week) than fruit (30.1%). There were significant differences between genders regarding intake of vegetables (P Sedentary behaviors (long duration of television viewing and Internet use) were highly prevalent, and physical activity was rarely practiced (6.8%). The findings indicated that risk factors for diet-related chronic diseases such as unhealthy dietary habits and sedentary behaviors are starting to rise among urban adolescents in Sudan. This creates the need for immediate action to prevent and control these risk factors before these diseases become major public health problems. © The Author(s) 2016.

  17. A brief review on correlates of physical activity and sedentariness in youth.

    NARCIS (Netherlands)

    van der Horst, K.; Paw, M.J.; Twisk, J.W.R.; van Mechelen, W.

    2007-01-01

    INTRODUCTION: Better understanding of the correlates of physical activity and sedentary behaviors in youth will support the development of effective interventions that promote a physically active lifestyle and prevent a sedentary lifestyle. The main goal of this systematic review is to summarize and

  18. Parent-child attitude congruence on type and intensity of physical activity: Testing multiple mediators of sedentary behavior in older children

    Science.gov (United States)

    This study examined parent–child attitudes on value of specific types and intensities of physical activity, which may explain gender differences in child activity, and evaluated physical activity as a mechanism to reduce time spent in sedentary behaviors. A community sample of 681 parents and 433 ch...

  19. Fracture toughness of a nanoscale WC-Co tool steel

    International Nuclear Information System (INIS)

    Densley, J.M.; Hirth, J.P.

    1997-01-01

    Tungsten carbide tool steels, comprising WC particles with 6.7--25wt% Co distributed in the interparticle regions as a quasi-continuous binder phase, can be considered as WC-Co composites. The fracture toughness of such WC-Co composites is dependent on the volume fraction, contiguity and thickness of the cobalt binder, and the size of the tungsten carbide grains. Research has shown that the ductile binder undergoes nearly all the plastic deformation during fracture, which provides the primary energy consuming process that enhances fracture resistance. Recent manufacturing developments have given rise to the production of a WC-6.7wt% Co cermet having an average WC grain size of 70 nm, with a corresponding binder mean thickness, h, of 9 nm calculated from d = h(1-V f )/V f where d = 70 nm and V f = 0.114. This composite has shown a higher wear resistance than that of conventional cermets in proportion to their hardness. Such improvement has been attributed to the difficulty in forming dislocations in the very small grains. There are also indications that the Co binder in the nanoscale cermet contains higher contents of dissolved W and C than for conventional scale cermets. Because plastic deformation is initially confined to the binder phase, it was of interest to perform mode 1 and mixed mode toughness tests on the nanoscale cermet to determine whether flow localization influenced mixed mode toughness as in bulk materials. Two generations of this cermet were provided by Rogers Tool Works. The first generation, A, had lower binder contiguity, with occasional agglomerations of WC grains. The second generation, B, was cleaner, with the cobalt binder more uniformly separating the WC grains

  20. Micromechanics of fracture in WC-Co hardmetals

    International Nuclear Information System (INIS)

    Dusza, J.; Parilak, L.

    1986-01-01

    A study has been made in WC-Co cemented carbides with grain sizes of 2.1 - 3.6 μm and 13 - 32 vol% Co, of the relationship between the fracture toughness and microstructural parameters and micromechanisms of fracture. Regression analyses have been used to derive empirical relationships between fracture toughness, and the binder spacing, the contiguity and the relative proportions of fracture in the binder phase and between contiguous WC grains

  1. Infrared processed Cu composites reinforced with WC particles

    International Nuclear Information System (INIS)

    Deshpande, P.K.; Li, J.H.; Lin, R.Y.

    2006-01-01

    Copper matrix composites with WC particle reinforcements have been prepared with an innovative infrared infiltration technique. The volume content of the reinforcement particles in the composite is about 53%. The relative composite density of as high as 99.9% has been obtained with this process. The electric conductivity of composites prepared in this study as determined by a four-point probe method, is similar to commercially available Cu/W composites containing 52 vol% tungsten. Microhardness, microstructure and wear resistance of the composites were also determined. The microstructure of Cu/WC composite reveals excellent wetting between the two constituent phases, WC and copper. The microhardness values of all completely infiltrated Cu/WC composites were in the range of 360-370 HV which is significantly higher than the microhardness of pure copper, 65 HV. Wear resistance of the composites was determined with a pin on disk wear test technique. The wear test results show that composites prepared in this study performed much better than those commercially available Cu/W composites by more than two-fold against silicon carbide abrasive disks

  2. Long-Term Correlates of Objectively Measured Physical Activity and Sedentary Time in Norwegian Men and Women.

    Science.gov (United States)

    Solbraa, Ane Kristiansen; Ekelund, Ulf; Holme, Ingar M; Graff-Iversen, Sidsel; Steene-Johannessen, Jostein; Aadland, Eivind; Anderssen, Sigmund Alfred

    2015-11-01

    Sex, age, body mass index (BMI), perceived health and health behavior are correlates known to affect physical activity and sedentary time. However, studies have often been cross-sectional, and less is known about long-term correlates. Thus, the aims were to investigate 1) the associations between a set of characteristics (demographic, biological, psychological, and behavioral) and objectively measured physical activity and sedentary time at 13-year follow-up, and 2) the association between changes in these characteristics over time and physical activity and sedentary time. Baseline characteristics were collected in 40-year-olds in 1996, and follow-up data on objectively measured physical activity and sedentary time were obtained in 2009 (n = 240). Data were analyzed by multiple linear regressions. Self-reported physical activity (P physical activity (MVPA) whereas BMI (P = .034) and increased BMI (P = .014) were negatively associated with MVPA at follow-up. Women spent less time being sedentary than men (P = .019). Education (P < .001) was positively associated and improved perceived health (P = .010) was negatively associated with sedentary time at follow-up. MVPA and sedentary time at follow-up were associated with behavioral, biological and demographic correlates. However, the nature of our analyses prevents us from inferring causality.

  3. Hot isostatic pressing of nanosized WC-Co hardmetals

    International Nuclear Information System (INIS)

    Azcona, I.; Ordonez, A.; Sanchez, J.M.; Castro, F.; Dominguez, L.

    2001-01-01

    A new technique based on hot isostatic pressing (HIP) has been developed to produce dense nanosized WC-Co hardmetals without the addition of grain growth inhibitors. The glass encapsulation process is the key for the effective application of isostatic pressure at temperatures well below those usually required for reaching the closed porosity state in the WC-Co system. Fully dense WC-Co samples with cobalt contents ranging from 10 to 12 wt. % have been obtained by this technique at temperatures between 1000 o C and 1200 o C with 150 MPa of applied isostatic pressure for 30 minutes. The role of isostatic pressure on the activation of densification mechanisms is discussed. (author)

  4. Developing Novel Machine Learning Algorithms to Improve Sedentary Assessment for Youth Health Enhancement.

    Science.gov (United States)

    Golla, Gowtham Kumar; Carlson, Jordan A; Huan, Jun; Kerr, Jacqueline; Mitchell, Tarrah; Borner, Kelsey

    2016-10-01

    Sedentary behavior of youth is an important determinant of health. However, better measures are needed to improve understanding of this relationship and the mechanisms at play, as well as to evaluate health promotion interventions. Wearable accelerometers are considered as the standard for assessing physical activity in research, but do not perform well for assessing posture (i.e., sitting vs. standing), a critical component of sedentary behavior. The machine learning algorithms that we propose for assessing sedentary behavior will allow us to re-examine existing accelerometer data to better understand the association between sedentary time and health in various populations. We collected two datasets, a laboratory-controlled dataset and a free-living dataset. We trained machine learning classifiers separately on each dataset and compared performance across datasets. The classifiers predict five postures: sit, stand, sit-stand, stand-sit, and stand\\walk. We compared a manually constructed Hidden Markov model (HMM) with an automated HMM from existing software. The manually constructed HMM gave more F1-Macro score on both datasets.

  5. The roles of physical activity and sedentary behavior on Hispanic children's mental health: a motor skill perspective.

    Science.gov (United States)

    Gu, Xiangli; Keller, M Jean; Weiller-Abels, Karen H; Zhang, Tao

    2018-01-01

    Motor competence (MC) has been recognized as the foundation for life-time moderate-to-vigorous physical activity (MVPA) as well as an influential factor in reducing sedentary behavior during childhood. Guided by Blair et al.'s health model, the purpose of this study was to examine the behavioral mechanism of mental health including physical, psychosocial, and cognitive health among Hispanic children related to MC and MVPA. A prospective research design was used with two-wave assessments across one academic year. A total of 141 Hispanic kindergarteners (Mean age  = 5.37, SD = 0.48) were recruited in Texas. Nearly all (94.3%) of the participants were from low-income families based on the Income Eligibility Guidelines. The study was approved by the University Research Review Board, and informed consent was obtained from parents/guardians prior to starting the study. Multiple regressions indicated that manipulative skill was a significant predictor of physical and psychosocial health (β = 0.21, β = 0.26, p health (β = 0.22, p mental health outcomes through MVPA (95% CI [0.031, 0.119]) and sedentary behavior (95% CI [0.054, 0.235]), respectively. The results suggest that skill-based activities/games, with instructions, should be encouraged during school-based physical activity and health promotion programs in childhood education. Better understanding of the early effects of MC may contribute to designing strategies to promote Hispanic children's well-being.

  6. Harnessing different motivational frames via mobile phones to promote daily physical activity and reduce sedentary behavior in aging adults.

    Directory of Open Access Journals (Sweden)

    Abby C King

    Full Text Available Mobile devices are a promising channel for delivering just-in-time guidance and support for improving key daily health behaviors. Despite an explosion of mobile phone applications aimed at physical activity and other health behaviors, few have been based on theoretically derived constructs and empirical evidence. Eighty adults ages 45 years and older who were insufficiently physically active, engaged in prolonged daily sitting, and were new to smartphone technology, participated in iterative design development and feasibility testing of three daily activity smartphone applications based on motivational frames drawn from behavioral science theory and evidence. An "analytically" framed custom application focused on personalized goal setting, self-monitoring, and active problem solving around barriers to behavior change. A "socially" framed custom application focused on social comparisons, norms, and support. An "affectively" framed custom application focused on operant conditioning principles of reinforcement scheduling and emotional transference to an avatar, whose movements and behaviors reflected the physical activity and sedentary levels of the user. To explore the applications' initial efficacy in changing regular physical activity and leisure-time sitting, behavioral changes were assessed across eight weeks in 68 participants using the CHAMPS physical activity questionnaire and the Australian sedentary behavior questionnaire. User acceptability of and satisfaction with the applications was explored via a post-intervention user survey. The results indicated that the three applications were sufficiently robust to significantly improve regular moderate-to-vigorous intensity physical activity and decrease leisure-time sitting during the 8-week behavioral adoption period. Acceptability of the applications was confirmed in the post-intervention surveys for this sample of midlife and older adults new to smartphone technology. Preliminary data

  7. Physical Fitness, Physical Activity, Sedentary Behavior, or Diet—What Are the Correlates of Obesity in Polish School Children?

    Science.gov (United States)

    Czyż, Stanisław H.; Toriola, Abel L.; Starościak, Wojciech; Lewandowski, Marek; Paul, Yvonne; Oyeyemi, Adewale L.

    2017-01-01

    There is substantial evidence of rising prevalence of overweight and obesity and its co-morbidities among children in western-high income developed countries. In the European Union, the prevalence of overweight and obesity is increasing fastest among Polish children. Yet, there is paucity of evidence on the relationship of behavioral factors with body weight status of children in Poland. This study examined the association of obesity with physical fitness, physical activity, sedentary behavior and diet among Polish children. A total of 641 children (10–15 years) recruited from the Lower Silesia region of Poland participated in this cross-sectional study. Participants’ anthropometrics, physical fitness, physical activity, sedentary behavior and dietary intake were assessed. Outcome variables were weight categories (according to body mass index [BMI], waist-to-hip ratio [WHR], and percentage body fat [% BF]). The strongest negative correlation was found between VO2max and %BF (r = −0.39, p children by 13%, 26% and 19%, respectively as compared to the group of obese children. VO2max and weight and obesity indices were strongly correlated in both gender and age groups. Education and intervention programs to increase physical fitness (VO2max) through aerobic training are recommended for Physical Education teachers, parents and children in order to reduce the rate of overweight and obesity among children in the Lower Silesia region of Poland. PMID:28632175

  8. Effects of Three Motivationally Targeted Mobile Device Applications on Initial Physical Activity and Sedentary Behavior Change in Midlife and Older Adults: A Randomized Trial.

    Directory of Open Access Journals (Sweden)

    Abby C King

    Full Text Available While there has been an explosion of mobile device applications (apps promoting healthful behaviors, including physical activity and sedentary patterns, surprisingly few have been based explicitly on strategies drawn from behavioral theory and evidence.This study provided an initial 8-week evaluation of three different customized physical activity-sedentary behavior apps drawn from conceptually distinct motivational frames in comparison with a commercially available control app.Ninety-five underactive adults ages 45 years and older with no prior smartphone experience were randomized to use an analytically framed app, a socially framed app, an affectively framed app, or a diet-tracker control app. Daily physical activity and sedentary behavior were measured using the smartphone's built-in accelerometer and daily self-report measures.Mixed-effects models indicated that, over the 8-week period, the social app users showed significantly greater overall increases in weekly accelerometry-derived moderate to vigorous physical activity relative to the other three arms (P values for between-arm differences = .04-.005; Social vs. Control app: d = 1.05, CI = 0.44,1.67; Social vs. Affect app: d = 0.89, CI = 0.27,1.51; Social vs. Analytic app: d = 0.89, CI = 0.27,1.51, while more variable responses were observed among users of the other two motivationally framed apps. Social app users also had significantly lower overall amounts of accelerometry-derived sedentary behavior relative to the other three arms (P values for between-arm differences = .02-.001; Social vs. Control app: d = 1.10,CI = 0.48,1.72; Social vs. Affect app: d = 0.94, CI = 0.32,1.56; Social vs. Analytic app: d = 1.24, CI = 0.59,1.89. Additionally, Social and Affect app users reported lower overall sitting time compared to the other two arms (P values for between-arm differences < .001; Social vs. Control app: d = 1.59,CI = 0.92, 2.25; Social vs. Analytic app: d = 1.89,CI = 1.17, 2.61; Affect

  9. Effects of Three Motivationally Targeted Mobile Device Applications on Initial Physical Activity and Sedentary Behavior Change in Midlife and Older Adults: A Randomized Trial.

    Science.gov (United States)

    King, Abby C; Hekler, Eric B; Grieco, Lauren A; Winter, Sandra J; Sheats, Jylana L; Buman, Matthew P; Banerjee, Banny; Robinson, Thomas N; Cirimele, Jesse

    2016-01-01

    While there has been an explosion of mobile device applications (apps) promoting healthful behaviors, including physical activity and sedentary patterns, surprisingly few have been based explicitly on strategies drawn from behavioral theory and evidence. This study provided an initial 8-week evaluation of three different customized physical activity-sedentary behavior apps drawn from conceptually distinct motivational frames in comparison with a commercially available control app. Ninety-five underactive adults ages 45 years and older with no prior smartphone experience were randomized to use an analytically framed app, a socially framed app, an affectively framed app, or a diet-tracker control app. Daily physical activity and sedentary behavior were measured using the smartphone's built-in accelerometer and daily self-report measures. Mixed-effects models indicated that, over the 8-week period, the social app users showed significantly greater overall increases in weekly accelerometry-derived moderate to vigorous physical activity relative to the other three arms (P values for between-arm differences = .04-.005; Social vs. Control app: d = 1.05, CI = 0.44,1.67; Social vs. Affect app: d = 0.89, CI = 0.27,1.51; Social vs. Analytic app: d = 0.89, CI = 0.27,1.51), while more variable responses were observed among users of the other two motivationally framed apps. Social app users also had significantly lower overall amounts of accelerometry-derived sedentary behavior relative to the other three arms (P values for between-arm differences = .02-.001; Social vs. Control app: d = 1.10,CI = 0.48,1.72; Social vs. Affect app: d = 0.94, CI = 0.32,1.56; Social vs. Analytic app: d = 1.24, CI = 0.59,1.89). Additionally, Social and Affect app users reported lower overall sitting time compared to the other two arms (P values for between-arm differences < .001; Social vs. Control app: d = 1.59,CI = 0.92, 2.25; Social vs. Analytic app: d = 1.89,CI = 1.17, 2.61; Affect vs. Control

  10. Shift workers have similar leisure-time physical activity levels as day workers but are more sedentary at work.

    Science.gov (United States)

    Hulsegge, Gerben; Gupta, Nidhi; Holtermann, Andreas; Jørgensen, Marie Birk; Proper, Karin I; van der Beek, Allard J

    2017-03-01

    Objective Physical inactivity has been hypothesized as an underlying factor for the association between shift work and adverse health outcomes. We compared leisure-time and occupational physical activity and sedentary behavior between day, night, and non-night shift workers. Methods We identified 612 day workers, 139 night shift workers and 61 non-night shift workers aged 18-65 years (54% men) in two Danish studies: the New method for Objective Measurements of physical Activity in Daily living (NOMAD) and the Danish Physical ACTivity cohort with Objective measurements (DPhacto) between 2011-2013. Sedentary behavior, light, and moderate-to-vigorous physical activity were measured using an accelerometer. Physical activity was expressed as percentage of leisure and work time spent in each activity. Linear regression analyses were used to test differences in physical activity and sedentary behavior between day, night, and non-night shift workers. Results No differences in leisure-time sedentary behavior and physical activity were observed between day and shift workers (P>0.05). Non-night shift workers spent 7.2% [95% confidence interval (95% CI) 2.3-12.1) more time in occupational sedentary behavior than day workers and 5.9% (95% CI -10.1- -1.7) and 1.9% (95% CI -3.7- -0.2) less time in occupational light and moderate-to-vigorous physical activity, respectively. Compared to day workers, night shift workers spent 4.3% (95% CI 2.4-6.1) more time at work in uninterrupted sedentary periods of ≥30 minutes. Conclusions Shift workers had similar leisure-time physical activity patterns as day workers, but were more sedentary at work. Future research should elucidate whether occupational physical inactivity and sedentary behavior contributes to shift work-related adverse health effects.

  11. Atomic composition of WC/ and Zr/O-terminated diamond Schottky interfaces close to ideality

    Energy Technology Data Exchange (ETDEWEB)

    Piñero, J.C., E-mail: josecarlos.pinero@uca.es [Dpto. Ciencias de los Materiales, Universidad de Cádiz, Puerto Real, Cádiz,11510 (Spain); Araújo, D. [Dpto. Ciencias de los Materiales, Universidad de Cádiz, Puerto Real, Cádiz,11510 (Spain); Fiori, A. [National Institute for Materials Science, Tsukuba, Ibaraki (Japan); Traoré, A. [Institut Néel, CNRS-UJF, av. des Martyrs, Grenoble,38042 France (France); Villar, M.P. [Dpto. Ciencias de los Materiales, Universidad de Cádiz, Puerto Real, Cádiz,11510 (Spain); Eon, D.; Muret, P.; Pernot, J. [Institut Néel, CNRS-UJF, av. des Martyrs, Grenoble,38042 France (France); Teraji, T. [National Institute for Materials Science, Tsukuba, Ibaraki (Japan)

    2017-02-15

    Highlights: • Metal/O-terminated diamond interfaces are analyzed by a variety of TEM techniques. • Thermal treatment is shown to modify structural and chemical interface properties. • Electrical behavior vs annealing is shown to be related with interface modification. • Interfaces are characterized with atomic resolution to probe inhomogeneities. • Oxide formation and modification is demonstrated in both Schottky diodes. - Abstract: Electrical and nano-structural properties of Zr and WC-based Schottky power diodes are compared and used for investigating oxide-related effects at the diamond/metal interface. Differences in Schottky barrier heights and ideality factors of both structures are shown to be related with the modification of the oxygen-terminated diamond/metal interface configuration. Oxide formation, oxide thickness variations and interfacial oxygen redistribution, associated with thermal treatment are demonstrated. Ideality factors close to ideality (n{sub WC} = 1.02 and n{sub Zr} = 1.16) are obtained after thermal treatment and are shown to be related with the relative oxygen content at the surface (OCR{sub WC} = 3.03 and OCR{sub Zr} = 1.5). Indeed, thermal treatment at higher temperatures is shown to promote an escape of oxygen for the case of the WC diode, while it generates a sharper accumulation of oxygen at the metal/diamond interface for the case of Zr diode. Therefore, the metal-oxygen affinity is shown to be a key parameter to improve diamond-based Schottky diodes.

  12. Descriptive analysis of preschool physical activity and sedentary behaviors - a cross sectional study of 3-year-olds nested in the SKOT cohort

    DEFF Research Database (Denmark)

    Møller, Niels Christian; Christensen, Line Brinch; Mølgaard, Christian

    2017-01-01

    BACKGROUND: Further collection of surveillance data is warranted, particularly in preschool populations, for optimizing future public health promotion strategies. This study aims to describe physical activity (PA) and sedentary behavior (SB) across different settings, including time in and out...

  13. The Seated Inactivity Trial (SIT): Physical Activity and Dietary Outcomes Associated With 8 Weeks of Imposed Sedentary Time.

    Science.gov (United States)

    Cull, Brooke J; Haub, Mark D; Rosenkranz, Richard R; Lawler, Thomas; Rosenkranz, Sara K

    2016-03-01

    Sedentary time is an independent risk factor for chronic diseases and mortality. It is unknown whether active adults alter their dietary and/or physical activity behaviors in response to imposed sedentary time, possibly modifying risk. The aim of this study was to determine whether imposed sedentary time would alter typical behaviors of active adults. Sixteen physically active, young adults were randomized to the no-intervention control (CON, n = 8) group or the sedentary-intervention (SIT, n = 8) group. SIT participants attended monitored sedentary sessions (8 wk, 10 h/wk). Assessments including diet and physical activity occurred at baseline, week 4, and week 9. There were no differences (P > .05) between CON and SIT groups for step counts or time spent in sedentary, light, moderate, or vigorous physical activity when comparing a week during imposed sedentary time (week 4) to baseline and week 9. At week 4, caloric intake was not different from baseline (P > .05) in either group. Caloric intake decreased significantly (P > .05) in SIT from baseline to week 9. Active adults did not alter physical activity or dietary behaviors during the imposed sedentary intervention. However, SIT reduced caloric intake from baseline to week 9, indicating a possible compensatory response to imposed sitting in active adults.

  14. Physical activity and sedentary behavior during pregnancy and postpartum, measured using hip and wrist-worn accelerometers

    Directory of Open Access Journals (Sweden)

    Kathryn R. Hesketh

    2018-06-01

    Full Text Available Background: Physical activity in pregnancy and postpartum is beneficial to mothers and infants. To advance knowledge of objective physical activity measurement during these periods, this study compares hip to wrist accelerometer compliance; assesses convergent validity (correlation between hip- and wrist-worn accelerometry; and assesses change in physical activity from pregnancy to postpartum. Methods: We recruited women during pregnancy (n = 100; 2014–2015, asking them to wear hip and wrist accelerometers for 7 days during Trimester 2 (T2, Trimester 3 (T3, and 3-, 6-, 9- and 12-months postpartum. We assessed average wear-time and correlations (axis-specific counts/minute, vector magnitude counts/day and step counts/day at T2, T3, and postpartum. Results: Compliance was higher for wrist-worn accelerometers. Hip and wrist accelerometers showed moderate to high correlations (Pearson's r 0.59 to 0.84. Hip-measured sedentary and active time differed little between T2 and T3. Moderate-to-vigorous physical activity decreased at T3 and remained low postpartum. Light physical activity increased and sedentary time decreased throughout the postpartum period. Conclusions: Wrist accelerometers may be preferable during pregnancy and appear comparable to hip accelerometers. As physical activity declines during later pregnancy and may not rebound post birth, support for re-engaging in physical activity earlier in the postpartum period may benefit women. Keywords: Physical activity, Pregnancy, Postpartum, Sedentary behavior, Measurement

  15. Objectively Measured Total and Occupational Sedentary Time in Three Work Settings

    Science.gov (United States)

    van Dommelen, Paula; Coffeng, Jennifer K.; van der Ploeg, Hidde P.; van der Beek, Allard J.; Boot, Cécile R. L.; Hendriksen, Ingrid J. M.

    2016-01-01

    Background Sedentary behaviour increases the risk for morbidity. Our primary aim is to determine the proportion and factors associated with objectively measured total and occupational sedentary time in three work settings. Secondary aim is to study the proportion of physical activity and prolonged sedentary bouts. Methods Data were obtained using ActiGraph accelerometers from employees of: 1) a financial service provider (n = 49 men, 31 women), 2) two research institutes (n = 30 men, 57 women), and 3) a construction company (n = 38 men). Total (over the whole day) and occupational sedentary time, physical activity and prolonged sedentary bouts (lasting ≥30 minutes) were calculated by work setting. Linear regression analyses were performed to examine general, health and work-related factors associated with sedentary time. Results The employees of the financial service provider and the research institutes spent 76–80% of their occupational time in sedentary behaviour, 18–20% in light intensity physical activity and 3–5% in moderate-to-vigorous intensity physical activity. Occupational time in prolonged sedentary bouts was 27–30%. Total time was less sedentary (64–70%), and had more light intensity physical activity (26–33%). The employees of the construction company spent 44% of their occupational time in sedentary behaviour, 49% in light, and 7% in moderate intensity physical activity, and spent 7% in sedentary bouts. Total time spent in sedentary behavior was 56%, 40% in light, and 4% in moderate intensity physical behaviour, and 12% in sedentary bouts. For women, low to intermediate education was the only factor that was negatively associated with occupational sedentary time. Conclusions Sedentary behaviour is high among white-collar employees, especially in highly educated women. A relatively small proportion of sedentary time was accrued in sedentary bouts. It is recommended that worksite health promotion efforts should focus on reducing sedentary

  16. Development and kinetic analysis of cobalt gradient formation in WC-Co composites

    Science.gov (United States)

    Guo, Jun

    2011-12-01

    Functionally graded cemented tungsten carbide (FG WC-Co) is one of the main research directions in the field of WC-Co over decades. Although it has long been recognized that FG WC-Co could outperform conventional homogeneous WC-Co owing to its potentially superior combinations of mechanical properties, until recently there has been a lack of effective and economical methods to make such materials. The lack of the technology has prevented the manufacturing and industrial applications of FG WC-Co from becoming a reality. This dissertation is a comprehensive study of an innovative atmosphere heat treatment process for producing FG WC-Co with a surface cobalt compositional gradient. The process exploited a triple phase field in W-C-Co phase diagram among three phases (solid WC, solid Co, and liquid Co) and the dependence of the migration of liquid Co on temperature and carbon content. WC-Co with a graded surface cobalt composition can be achieved by controlling the diffusion of carbon transported from atmosphere during sintering or during postsintering heat treatment. The feasibility of the process was validated by the successful preparations of FG WC-Co via both carburization and decarburization process following conventional liquid phase sintering. A study of the carburization process was undertaken to further understand and quantitatively modeled this process. The effects of key processing parameters (including heat treating temperature, atmosphere, and time) and key materials variables (involving Co content, WC grain size, and addition of grain growth inhibitors) on the formation of Co gradients were examined. Moreover, a carbon-diffusion controlled kinetic model was developed for simulating the formation of the gradient during the process. The parameters involved in this model were determined by thermodynamic calculations and regression-fit of simulation results with experimental data. In summary, this research first demonstrated the principle of the approach

  17. Phase size distribution in WC/Co hardmetal

    International Nuclear Information System (INIS)

    Roebuck, B.; Bennett, E.G.

    1986-01-01

    A high-resolution field emission scanning electron microscope was used to perform accurate quantitative metallography on a variety of WC/Co hardmetals. Particular attention was paid to obtaining the mean size and size distribution of the cobalt phase by linear analysis. Cobalt regions are frequently submicron and difficult to resolve adequately by conventional methods. The WC linear intercept distributions, and contiguity were also measured at the same time. The results were used to examine the validity of theoretic derivations of cobalt intercept size

  18. Decreasing Sedentary Behavior: Effects on Academic Performance, Meta-Cognition, and Sleep

    Directory of Open Access Journals (Sweden)

    June J. Pilcher

    2017-05-01

    Full Text Available There is growing interest in using activity workstations as a method of increasing light physical activity in normally sedentary environments. The current study (N = 117 compared the effects of studying in college students while slowly pedaling a stationary bike with a desktop with studying at traditional desks across 10 weeks in an academic semester. The students were assigned to study either on the stationary bike or at a traditional desk located in the campus library for a minimum of 2 h a week. During the 10 weeks, the students studied for tests or worked on other required academic activities while working at their assigned desk. In addition, the participants completed a pre survey, weekly surveys, and a post survey. We found that although students studying at the traditional desks reported more ease of studying and more effective studying than those using the stationary bikes, the two groups performed equally well on tests in an introductory psychology course. Moreover, the students using the traditional desks reported a decrease in sleep quality later in the semester while those using the activity workstation reported stable levels of sleep quality. The current results indicate that activity workstations could be implemented in university settings to encourage light physical activity without negatively affecting academic performance while providing possible long-term health and well-being benefits. Furthermore, the results suggests that activity workstations could be a means of combating sedentary behavior in environments where individuals are expected to sit either while waiting (e.g., doctor's waiting rooms, airports or when completing a necessary task (e.g., the workplace, educational settings.

  19. Microstructure and wear resistance of laser cladded composite coatings prepared from pre-alloyed WC-NiCrMo powder with different laser spots

    Science.gov (United States)

    Yao, Jianhua; Zhang, Jie; Wu, Guolong; Wang, Liang; Zhang, Qunli; Liu, Rong

    2018-05-01

    The distribution of WC particles in laser cladded composite coatings can significantly affect the wear resistance of the coatings under aggressive environments. In this study, pre-alloyed WC-NiCrMo powder is deposited on SS316L via laser cladding with circular spot and wide-band spot, respectively. The microstructure and WC distribution of the coatings are investigated with optical microscope (OM), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and X-ray diffraction (XRD). The wear behavior of the coatings is investigated under dry sliding-wear test. The experimental results show that the partially dissolved WC particles are uniformly distributed in both coatings produced with circular spot and wide-band spot, respectively, and the microstructures consist of WC and M23C6 carbides and γ-(Ni, Fe) solid solution matrix. However, due to Fe dilution, the two coatings have different microstructural characteristics, resulting in different hardness and wear resistance. The wide-band spot laser prepared coating shows better performance than the circular spot laser prepared coating.

  20. Physical activity and sedentary behavior measured objectively and subjectively in overweight and obese adults with schizophrenia or schizoaffective disorders.

    Science.gov (United States)

    Janney, Carol A; Ganguli, Rohan; Tang, Gong; Cauley, Jane A; Holleman, Robert G; Richardson, Caroline R; Kriska, Andrea M

    2015-10-01

    Describe objective and subjective physical activity levels and time spent being sedentary in adults with schizophrenia or schizoaffective disorders (SZO/SA). Baseline physical activity and sedentary behaviors were assessed among 46 overweight and obese community-dwelling adults (aged 18-70 years; BMI > 27 kg/m(2)) diagnosed with SZO/SA by DSM-IV-TR, with mild symptom severity (Positive and Negative Syndrome Scale score physical activity levels, measured using actigraphs, in WAIST were compared to a nationally representative sample of users (n = 46) and nonusers (n = 46) of mental health service (MHS) from the National Health and Nutrition Examination Survey (NHANES 2003-2004) matched by sex, BMI, and age. On average, adults with SZO/SA wore actigraphs more than 15 h/d for 7 days averaging 151,000 counts/d. The majority of monitoring time (81%) was classified as sedentary (approximately 13 h/d). Moderate/vigorous and light physical activity accounted for only 2% (19 min/d) and 17% (157 min/d) of monitoring time/d, respectively. Primary source of activity was household activities (409 ± 438 min/wk). Fifty-three percent reported walking for transportation or leisure. Adults with SZO/SA were significantly less active (176 min/d) and more sedentary (756 min/d) than NHANES users of MHS (293 and 640 min/d, respectively) and nonusers of MHS (338 and 552 min/d, respectively) (P physical activity; and significantly less active than NHANES users and nonusers of MHS. This sedentary lifestyle is significantly lower than those of other inactive US populations, is costly for the individual and community, and highlights the need for physical activity promotion and interventions in this high risk population. © Copyright 2015 Physicians Postgraduate Press, Inc.

  1. Sedentary behavior and prostate cancer risk in the NIH-AARP Diet and Health Study.

    Science.gov (United States)

    Lynch, Brigid M; Friedenreich, Christine M; Kopciuk, Karen A; Hollenbeck, Albert R; Moore, Steven C; Matthews, Charles E

    2014-05-01

    Sedentary behavior (sitting time) has been proposed as an independent risk factor for some cancers; however, its role in the development of prostate cancer has not been determined. We examined the prospective associations of self-reported daily sitting time and daily television/video viewing time with the risk of developing or dying from prostate cancer among 170,481 men in the NIH-AARP Diet and Health Study. We estimated HRs and 95% confidence intervals (CI) using Cox proportional hazards regression. Between 1996 and 2006, there were 13,751 incident (including 1,365 advanced) prostate cancer cases identified; prostate cancer mortality (through 2008) was 669. No strong or significant association with prostate cancer risk was seen in fully adjusted models for either daily sitting or television/video time. There were some suggestions of effect modification by body mass index (BMI; interaction for television/video time and BMI, P = 0.02). For total prostate cancer risk, television/video time was associated with a slightly elevated, but nonsignificant, increase amongst obese men (HR = 1.28; 95% CI, 0.98-1.69); a null association was observed amongst overweight men (HR = 1.04; 0.89-1.22); and, for men with a normal BMI, television/video time was associated with a nonsignificant risk decrease (HR = 0.82; 95% CI, 0.66-1.01). Similar patterns were observed for total daily sitting and television/video time in advanced prostate cancer and prostate cancer mortality. Sedentary behavior seems to play a limited role in the development of prostate cancer; however, we cannot rule out potential effect modification by BMI or the impact of measurement error on results. ©2014 AACR.

  2. Using the Intervention Mapping and Behavioral Intervention Technology Frameworks: Development of an mHealth Intervention for Physical Activity and Sedentary Behavior Change.

    Science.gov (United States)

    Direito, Artur; Walsh, Deirdre; Hinbarji, Moohamad; Albatal, Rami; Tooley, Mark; Whittaker, Robyn; Maddison, Ralph

    2018-06-01

    Few interventions to promote physical activity (PA) adapt dynamically to changes in individuals' behavior. Interventions targeting determinants of behavior are linked with increased effectiveness and should reflect changes in behavior over time. This article describes the application of two frameworks to assist the development of an adaptive evidence-based smartphone-delivered intervention aimed at influencing PA and sedentary behaviors (SB). Intervention mapping was used to identify the determinants influencing uptake of PA and optimal behavior change techniques (BCTs). Behavioral intervention technology was used to translate and operationalize the BCTs and its modes of delivery. The intervention was based on the integrated behavior change model, focused on nine determinants, consisted of 33 BCTs, and included three main components: (1) automated capture of daily PA and SB via an existing smartphone application, (2) classification of the individual into an activity profile according to their PA and SB, and (3) behavior change content delivery in a dynamic fashion via a proof-of-concept application. This article illustrates how two complementary frameworks can be used to guide the development of a mobile health behavior change program. This approach can guide the development of future mHealth programs.

  3. Which psychological, social and physical environmental characteristics predict changes in physical activity and sedentary behaviors during early retirement? A longitudinal study

    Directory of Open Access Journals (Sweden)

    Delfien Van Dyck

    2017-05-01

    Full Text Available Background In the context of healthy ageing, it is necessary to identify opportunities to implement health interventions in order to develop an active lifestyle with sufficient physical activity and limited sedentary time in middle-aged and older adults. The transition to retirement is such an opportunity, as individuals tend to establish new routines at the start of retirement. Before health interventions can be developed, the psychological, social and physical environmental determinants of physical activity and sedentary behaviors during early retirement should be identified, ideally with longitudinal studies. The aim of this paper was first to examine whether psychological, social and physical environmental factors at the start of retirement predict longitudinal changes in physical activity and sedentary behaviors during the first years of retirement. Second, moderating effects of gender and educational levels were examined. Methods This longitudinal study was conducted in Flanders, Belgium. In total, 180 recently retired (>1 month, <2 years at baseline adults completed a postal questionnaire twice (in 2012–2013 and two years later in 2014–2015. The validated questionnaire assessed socio-demographic information, physical activity, sedentary behaviors, and psychological, social and physical environmental characteristics. Multiple moderated hierarchic regression analyses were conducted in SPSS 22.0. Results Higher perceived residential density (p < 0.001 and lower aesthetics (p = 0.08 predicted an increase in active transportation (adjusted R2 = 0.18. Higher baseline self-efficacy was associated with an increase in leisure-time physical activity (p = 0.001, adjusted R2 = 0.13. A more positive perception of old age (p = 0.04 and perceiving less street connectivity (p = 0.001 were associated with an increase in screen time (adjusted R2 = 0.06. Finally, higher baseline levels of modeling from friends (p = 0.06 and lower

  4. Prospective associations between measures of gross and fine motor coordination in infants and objectively measured physical activity and sedentary behavior in childhood.

    Science.gov (United States)

    Sánchez, Guillermo F López; Williams, Genevieve; Aggio, Daniel; Vicinanza, Domenico; Stubbs, Brendon; Kerr, Catherine; Johnstone, James; Roberts, Justin; Smith, Lee

    2017-11-01

    One important determinant of childhood physical activity and sedentary behavior may be that of motor development in infancy. The present analyses aimed to investigate whether gross and fine motor delays in infants were associated with objective and self-reported activity in childhood. Data were from the UK Millennium Cohort Study, a prospective cohort study, involving UK children born on or around the millennium (September 2000 and January 2002). When children were 9 months old, parents reported children's fine and gross motor-coordination, and at 7 years, sports club attendance and daily TV viewing time. Children's physical activity was measured using accelerometers at 7 years. Adjusted regression models were used to examine associations between delayed motor development and accelerometry measured moderate-to-vigorous physical activity and sedentary behavior, and parent-reported sport club attendance and TV viewing time. In this sample (n = 13,021), gross motor delay in infancy was associated with less time in moderate-to-vigorous physical activity (B -5.0 95% confidence interval [CI] -6.8, -3.2) and more time sedentary (B 13.5 95% CI 9.3, 17.8) in childhood. Gross and fine motor delays during infancy were associated with a reduced risk of having high attendance at sports clubs in childhood (both relative risk [RR] 0.7, 95% CI 0.6, 0.9). Fine motor delays, but not gross delays, were also associated with an increased risk of having high TV viewing time (RR 1.3 95% CI 1.0, 1.6). Findings from the present study suggest that delays in motor development in infancy are associated with physical activity and sedentary time in childhood.

  5. Are physical activity, sedentary behaviors and sleep duration associated with body mass index-for-age and health-related quality of life among high school boys and girls?

    Science.gov (United States)

    Jalali-Farahani, Sara; Amiri, Parisa; Chin, Yit Siew

    2016-02-27

    Previous studies reported lower health-related quality of life (HRQOL) scores in overweight and obese adolescents compared to their normal weight counterparts; however, few studies investigated the association between obesity-related behaviors including physical activity and sedentary behaviors and HRQOL in adolescents. This study aimed at investigating the relationship between physical activity, sedentary behaviors, sleep duration and body mass index-for-age (BMI-for-age) and HRQOL among high school Tehranian students. A total of 465 high school students (48.8 % girls) were recruited from three different socio-economic zones in Tehran. The BMI-for-age was determined and physical activity and HRQOL were assessed using validated questionnaires including Quantification de l'Activite Physique en Altitude Chez les Enfants (QAPACE) and Pediatric Quality of Life Inventory (PedsQL) respectively. Over one third of students (38.5 %) were either overweight or obese. The means of all self- and parent-reported HRQOL scores were significantly lower in girls, compared to boys, except for the parent-reported social functioning subscale. Mean hours of daily sleeping were significantly higher in girls, compared to boys (8.16 ± 1.27 vs. 7.73 ± 1.22 respectively; p girls and boys spent more time on sedentary activities than engaging in sport activities. During school and vacation periods, boys had significantly higher daily energy expenditure (DEE) compared to girls (p boys but not girls (r = -0.14, p activities were significantly associated with their children HRQOL scores. In summary, time spent on physical and sedentary activities were not associated with BMI-for-age, although both of these were associated with the HRQOL of high school students. The potential role of sedentary activities and physical activity should be considered in future interventions aimed at improving HRQOL in adolescents.

  6. Comparison of summer and winter objectively measured physical activity and sedentary behavior in older adults

    DEFF Research Database (Denmark)

    Arnardottir, Nanna Yr; Oskarsdottir, Nina Dora; Brychta, Robert J.

    2017-01-01

    In Iceland, there is a large variation in daylight between summer and winter. The aim of the study was to identify how this large variation influences physical activity (PA) and sedentary behavior (SB). Free living PA was measured by a waist-worn accelerometer for one week during waking hours...... categories, except for the moderate-to-vigorous PA (MVPA), and SB was reduced. More lifestyle PA (LSPA) was accumulated in ≥5-min bouts during summer than winter, especially among highly active participants. This information could be important for policy makers and health professionals working with older...

  7. The Particle Shape of WC Governing the Fracture Mechanism of Particle Reinforced Iron Matrix Composites.

    Science.gov (United States)

    Li, Zulai; Wang, Pengfei; Shan, Quan; Jiang, Yehua; Wei, He; Tan, Jun

    2018-06-11

    In this work, tungsten carbide particles (WC p , spherical and irregular particles)-reinforced iron matrix composites were manufactured utilizing a liquid sintering technique. The mechanical properties and the fracture mechanism of WC p /iron matrix composites were investigated theoretically and experimentally. The crack schematic diagram and fracture simulation diagram of WC p /iron matrix composites were summarized, indicating that the micro-crack was initiated both from the interface for spherical and irregular WC p /iron matrix composites. However, irregular WC p had a tendency to form spherical WC p . The micro-cracks then expanded to a wide macro-crack at the interface, leading to a final failure of the composites. In comparison with the spherical WC p , the irregular WC p were prone to break due to the stress concentration resulting in being prone to generating brittle cracking. The study on the fracture mechanisms of WC p /iron matrix composites might provide a theoretical guidance for the design and engineering application of particle reinforced composites.

  8. Methods to estimate aspects of physical activity and sedentary behavior from high-frequency wrist accelerometer measurements.

    Science.gov (United States)

    Staudenmayer, John; He, Shai; Hickey, Amanda; Sasaki, Jeffer; Freedson, Patty

    2015-08-15

    This investigation developed models to estimate aspects of physical activity and sedentary behavior from three-axis high-frequency wrist-worn accelerometer data. The models were developed and tested on 20 participants (n = 10 males, n = 10 females, mean age = 24.1, mean body mass index = 23.9), who wore an ActiGraph GT3X+ accelerometer on their dominant wrist and an ActiGraph GT3X on the hip while performing a variety of scripted activities. Energy expenditure was concurrently measured by a portable indirect calorimetry system. Those calibration data were then used to develop and assess both machine-learning and simpler models with fewer unknown parameters (linear regression and decision trees) to estimate metabolic equivalent scores (METs) and to classify activity intensity, sedentary time, and locomotion time. The wrist models, applied to 15-s windows, estimated METs [random forest: root mean squared error (rSME) = 1.21 METs, hip: rMSE = 1.67 METs] and activity intensity (random forest: 75% correct, hip: 60% correct) better than a previously developed model that used counts per minute measured at the hip. In a separate set of comparisons, the simpler decision trees classified activity intensity (random forest: 75% correct, tree: 74% correct), sedentary time (random forest: 96% correct, decision tree: 97% correct), and locomotion time (random forest: 99% correct, decision tree: 96% correct) nearly as well or better than the machine-learning approaches. Preliminary investigation of the models' performance on two free-living people suggests that they may work well outside of controlled conditions. Copyright © 2015 the American Physiological Society.

  9. Sedentary bout durations and metabolic syndrome among working adults: a prospective cohort study.

    Science.gov (United States)

    Honda, Takanori; Chen, Sanmei; Yonemoto, Koji; Kishimoto, Hiro; Chen, Tao; Narazaki, Kenji; Haeuchi, Yuka; Kumagai, Shuzo

    2016-08-26

    This study aimed to examine the associations between time spent in prolonged and non-prolonged sedentary bouts and the development of metabolic syndrome. We used data from a prospective study of Japanese workers. Baseline examination was conducted between 2010 and 2011. A total of 430 office workers (58 women) aged 40-64 years without metabolic syndrome were followed up by annual health checkups until 2014. Metabolic syndrome was defined as having ≥ 3 out of 5 diagnostic criteria from the Joint Interim Statement 2009 definition. Sedentary time was assessed using a tri-axial accelerometer. Time spent in total, prolonged (accumulated ≥ 30 min) and non-prolonged sedentary bouts (accumulated metabolic syndrome. During a median follow-up of 3 years, 83 participants developed metabolic syndrome. After adjustment for age, sex, education, smoking, and family income, positive associations were observed between time spent in prolonged sedentary bouts and the development of metabolic syndrome. After additional adjustment for moderate-to-vigorous physical activity, those in the three highest quartiles of time spent in prolonged sedentary bouts showed higher risk of metabolic syndrome compared to the lowest quartile group, with adjusted hazard ratios (95 % confidence intervals) of 2.72 (1.30 - 5.73), 2.42 (1.11 - 5.50), and 2.85 (1.31 - 6.18), respectively. No associations were seen for time spent in total and non-prolonged sedentary bouts. Sedentary behavior accumulated in a prolonged manner was associated with an increased risk of metabolic syndrome. In devising public health recommendations for the prevention of metabolic disease, the avoidance of prolonged uninterrupted periods of sedentary behavior should be considered.

  10. Devices for Self-Monitoring Sedentary Time or Physical Activity: A Scoping Review.

    Science.gov (United States)

    Sanders, James P; Loveday, Adam; Pearson, Natalie; Edwardson, Charlotte; Yates, Thomas; Biddle, Stuart J H; Esliger, Dale W

    2016-05-04

    It is well documented that meeting the guideline levels (150 minutes per week) of moderate-to-vigorous physical activity (PA) is protective against chronic disease. Conversely, emerging evidence indicates the deleterious effects of prolonged sitting. Therefore, there is a need to change both behaviors. Self-monitoring of behavior is one of the most robust behavior-change techniques available. The growing number of technologies in the consumer electronics sector provides a unique opportunity for individuals to self-monitor their behavior. The aim of this study is to review the characteristics and measurement properties of currently available self-monitoring devices for sedentary time and/or PA. To identify technologies, four scientific databases were systematically searched using key terms related to behavior, measurement, and population. Articles published through October 2015 were identified. To identify technologies from the consumer electronic sector, systematic searches of three Internet search engines were also performed through to October 1, 2015. The initial database searches identified 46 devices and the Internet search engines identified 100 devices yielding a total of 146 technologies. Of these, 64 were further removed because they were currently unavailable for purchase or there was no evidence that they were designed for, had been used in, or could readily be modified for self-monitoring purposes. The remaining 82 technologies were included in this review (73 devices self-monitored PA, 9 devices self-monitored sedentary time). Of the 82 devices included, this review identified no published articles in which these devices were used for the purpose of self-monitoring PA and/or sedentary behavior; however, a number of technologies were found via Internet searches that matched the criteria for self-monitoring and provided immediate feedback on PA (ActiGraph Link, Microsoft Band, and Garmin Vivofit) and sedentary time (activPAL VT, the Lumo Back, and Darma

  11. Physical Fitness, Physical Activity, Sedentary Behavior, or Diet—What Are the Correlates of Obesity in Polish School Children?

    OpenAIRE

    Stanisław H. Czyż; Abel L. Toriola; Wojciech Starościak; Marek Lewandowski; Yvonne Paul; Adewale L. Oyeyemi

    2017-01-01

    There is substantial evidence of rising prevalence of overweight and obesity and its co-morbidities among children in western-high income developed countries. In the European Union, the prevalence of overweight and obesity is increasing fastest among Polish children. Yet, there is paucity of evidence on the relationship of behavioral factors with body weight status of children in Poland. This study examined the association of obesity with physical fitness, physical activity, sedentary behavio...

  12. Fundamental motor skill, physical activity, and sedentary behavior in socioeconomically disadvantaged kindergarteners.

    Science.gov (United States)

    Gu, Xiangli

    2016-10-01

    Guided by Stodden et al's conceptual model, the main purpose of the study was to examine the relation between fundamental motor skills (FMS; locomotor and objective control skills), different intensity levels of physical activity (light PA [LPA], moderate-to-vigorous PA [MVPA], and vigorous PA[VPA]), and sedentary behavior (SB) in socioeconomically disadvantaged kindergarteners. A prospective design was used in this study and the data were collected across the 2013-2014 academic school year. Participants were 256 (129 boys; 127 girls; Mage = 5.37, SD = 0.48) kindergarteners recruited from three public schools in the southern United States. Results found that FMS were significantly related to LPA, MVPA, VPA, and SB. Regression analyses indicate that locomotor skills explained significant variance for LPA (6.4%; p < .01), MVPA (7.9%; p < .001), and VPA (5.3%; p < .01) after controlling for weight status. Mediational analysis supports the significant indirect effect of MVPA on the relation between FMS and SB (95% CI: [-0.019, -0.006]). Adequate FMS development during early childhood may result in participating in more varied physical activities, thus leading to lower risk of obesity-related behaviors.

  13. An objective assessment of toddlers' physical activity and sedentary levels: a cross-sectional study.

    Science.gov (United States)

    Vanderloo, Leigh M; Tucker, Patricia

    2015-09-26

    Little evidence exists on the physical activity and sedentary time of Canadian toddlers; this study objectively measured such behaviors and compared participants' activity levels to national guidelines. Levels of screen-viewing among toddlers were also explored. Forty toddlers (mean age = 25.7 months) wore Actical accelerometers for seven consecutive days (15 s epoch). Parents/guardians completed a wear-time log and a demographic and screen-viewing questionnaire. Descriptive analyses were used to determine participants' levels of physical activity and sedentary time, to identify whether toddlers were meeting physical activity/sedentary guidelines, and to explore demographic variables. T-tests were used to assess whether toddlers' activity levels differed based on cut-points applied and various demographic and screen-related variables. Regression analyses were conducted to examine associations between toddlers' sedentary time and screen-viewing levels. Toddlers engaged in 37.27 (SD = 3.79) to 49.40 (SD = 3.29) mins/hr of sedentary time, 9.79 (SD = 2.90) to 18.78 (SD = 3.22) mins/hr of light-intensity physical activity (LPA), 0.82 (SD = 0.72) to 3.95 (SD = 1.93) mins/hr of moderate- to vigorous-intensity physical activity (MVPA), and 10.60 (SD =3.29) to 22.73 (SD = 3.97) mins/hr of total physical activity (TPA), based on the Trost et al. and the Canadian Health Measures Survey (CHMS) cut-points respectively; these rates were significantly different (p physical activity guidelines. No statistically significant differences in sedentary time or physical activity (all intensities) based on sex were reported (p sedentary behavior guidelines on weekdays and weekend days, respectively. The implications of this work suggest that a greater understanding of toddlers' activity patterns is needed; additional mechanisms of promoting active behaviors among this group should be explored.

  14. The influence of a consumer-wearable activity tracker on sedentary time and prolonged sedentary bouts: secondary analysis of a randomized controlled trial.

    Science.gov (United States)

    Sloan, Robert A; Kim, Youngdeok; Sahasranaman, Aarti; Müller-Riemenschneider, Falk; Biddle, Stuart J H; Finkelstein, Eric A

    2018-03-22

    A recent meta-analysis surmised pedometers were a useful panacea to independently reduce sedentary time (ST). To further test and expand on this deduction, we analyzed the ability of a consumer-wearable activity tracker to reduce ST and prolonged sedentary bouts (PSB). We originally conducted a 12-month randomized control trial where 800 employees from 13 organizations were assigned to control, activity tracker, or one of two activity tracker plus incentive groups designed to increase step count. The primary outcome was accelerometer measured moderate-to-vigorous physical activity. We conducted a secondary analysis on accelerometer measured daily ST and PSB bouts. A general linear mixed model was used to examine changes in ST and prolonged sedentary bouts, followed by between-group pairwise comparisons. Regression analyses were conducted to examine the association of changes in step counts with ST and PSB. The changes in ST and PSB were not statistically significant and not different between the groups (P consumer-wearable activity trackers as a means to reduce sedentary behavior. Trial registration NCT01855776 Registered: August 8, 2012.

  15. Psychometric Properties of a Scale to Assess Parental Self-Efficacy for Influencing Children's Dietary, Physical Activity, Sedentary, and Screen Time Behaviors in Disadvantaged Areas

    Science.gov (United States)

    Norman, Åsa; Bohman, Benjamin; Nyberg, Gisela; Schäfer Elinder, Liselotte

    2018-01-01

    Background: According to social cognitive theory, self-efficacy is central to behavior change. Consequently, parental self-efficacy (PSE) for influencing children's dietary, physical activity (PA), sedentary, and screen time behaviors is important for child obesity prevention. The aim of this study was to evaluate the psychometric properties of an…

  16. Project SHINE: effects of parent-adolescent communication on sedentary behavior in African American adolescents.

    Science.gov (United States)

    St George, Sara M; Wilson, Dawn K; Schneider, Elizabeth M; Alia, Kassandra A

    2013-10-01

    This study examined parenting variables (communication, monitoring) as moderators of a family-based intervention for reducing sedentary behavior (SB) in African American adolescents. As a secondary aim, a similar model was tested using adolescent weight status as the outcome. African American adolescents (n = 73; 12.45 ± 1.45 years; 60% girls; 63% overweight/obese) and caregivers were randomized to a 6-week interactive, parent-based intervention or general health condition. Parent-adolescent communication and monitoring of health behaviors were self-reported by parents. Adolescent SB was self-reported by youth. There was a significant intervention by communication interaction, such that intervention families with more positive communication showed lower adolescent SB than those with less positive communication or those in the comparison condition. No effects were found for monitoring on SB or for the model with weight status as the outcome. Parent-adolescent communication may be an effective component to integrate into health promotion programs for African American adolescents.

  17. Effect of physical activity and sedentary behavior on serum prostate-specific antigen concentrations: results from the National Health and Nutrition Examination Survey (NHANES), 2003-2006.

    Science.gov (United States)

    Loprinzi, Paul D; Kohli, Manish

    2013-01-01

    To examine the association between accelerometer-derived sedentary and physical activity and prostate-specific antigen (PSA) in a nationally representative sample of men in the United States. Data from the 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey cycles were used in the present study, with data from 1672 adult male participants used in the analyses. The manuscript was prepared between July 7, 2012, and September 26, 2012. Sedentary and physical activity was objectively measured using an accelerometer. Covariates included various demographic, dietary, biological, and immunologic variables including age, height, weight, body mass index, race/ethnicity, marital status, education, and poverty-income ratio; dietary fiber, fat, protein, and carbohydrate intake and total energy intake; vitamin C and vitamin E; alcohol intake; medication use; concentrations of cotinine, total cholesterol, and high-density lipoprotein cholesterol; blood pressure (elevated or not elevated); diabetes; C-reactive protein; and white blood cell count and number of basophils and eosinophils. Only after controlling for all covariates, for every 1-hour increase in sedentary behavior, participants were 16% more likely to have an elevated PSA concentration (odds ratio, 1.16 [95% CI, 1.06-1.27]; P=.001). For every 1-hour increase in light physical activity, participants were 18% less likely to have an elevated PSA concentration (odds ratio, 0.82 [95% CI, 0.68-1.00]; P=.05). Individuals who engage in more sedentary behavior and lower levels of light physical activity have higher PSA concentrations. Future studies are needed to better identify the potential underlying mechanisms delineating the association between sedentary and physical activity and PSA concentration. Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  18. Relative Contribution of Obesity, Sedentary Behaviors and Dietary Habits to Sleep Duration Among Kuwaiti Adolescents.

    Science.gov (United States)

    Al-Haifi, Ahmad A; AlMajed, Hana Th; Al-Hazzaa, Hazzaa M; Musaiger, Abdulrahman O; Arab, Mariam A; Hasan, Rasha A

    2015-05-17

    The aim of this study was to investigate whether body mass index (BMI), eating habits and sedentary behaviours were associated with sleep duration among Kuwaiti adolescents. The study is part of the Arab Teens Lifestyle Study (ATLS), which is a school-based cross-sectional multi-center collaborative study. A sample of 906 adolescents (boys and girls) aged 14-19 years was randomly selected from 6 Kuwaiti Governances using a multistage stratified cluster sampling technique. The findings revealed that the prevalence of overweight and obesity was 50.5% in boys and 46.5% in girls. The majority of boys (76%) and of girls (74%) fell into the short sleep duration category (6 hours/day or less). Sleep duration were found to be negatively associated with BMI (girls only). Watching television (boys and girls) and working on computers (boys only) were also negatively associated with sleep duration. While the consumption of breakfast (both genders) and milk (boys only) was positively associated with sleep duration (pgenders), sugar-sweetened drinks and sweets (boys only) potatoes (girls only) were negatively associated with sleep duration (peating habits and more sedentary behaviors. The findings also suggest gender differences in these associations. Therefore, adequate sleep is an important modifiable risk factor to prevent obesity and was positively associated with some unhealthy lifestyle habits.

  19. Lightning Tests on the WC-130 Research Aircraft.

    Science.gov (United States)

    1982-12-01

    in the WC-136 tests at various times.) E- Feild Fiber Optic Test Article Sensor Transmitter (Typ)WiePr Indtuced Voltag Sensor"" *Fiber I"=Current optic...well-characterized. 5.1 Skin Current Measurements Skin current vectors were measured at five fuselage locations on the left side of the WC-130 at a...MGL-S7) which were mounted so that they sampled two orthogonal components of the skin current vector . The measured responses were then inte- grated

  20. Sedentary bout durations and metabolic syndrome among working adults: a prospective cohort study

    Directory of Open Access Journals (Sweden)

    Takanori Honda

    2016-08-01

    Full Text Available Abstract Background This study aimed to examine the associations between time spent in prolonged and non-prolonged sedentary bouts and the development of metabolic syndrome. Methods We used data from a prospective study of Japanese workers. Baseline examination was conducted between 2010 and 2011. A total of 430 office workers (58 women aged 40-64 years without metabolic syndrome were followed up by annual health checkups until 2014. Metabolic syndrome was defined as having ≥ 3 out of 5 diagnostic criteria from the Joint Interim Statement 2009 definition. Sedentary time was assessed using a tri-axial accelerometer. Time spent in total, prolonged (accumulated ≥ 30 min and non-prolonged sedentary bouts (accumulated < 30 min was calculated. Cox proportional hazards models were used to estimate the risk of developing metabolic syndrome. Results During a median follow-up of 3 years, 83 participants developed metabolic syndrome. After adjustment for age, sex, education, smoking, and family income, positive associations were observed between time spent in prolonged sedentary bouts and the development of metabolic syndrome. After additional adjustment for moderate-to-vigorous physical activity, those in the three highest quartiles of time spent in prolonged sedentary bouts showed higher risk of metabolic syndrome compared to the lowest quartile group, with adjusted hazard ratios (95 % confidence intervals of 2.72 (1.30 – 5.73, 2.42 (1.11 – 5.50, and 2.85 (1.31 – 6.18, respectively. No associations were seen for time spent in total and non-prolonged sedentary bouts. Conclusions Sedentary behavior accumulated in a prolonged manner was associated with an increased risk of metabolic syndrome. In devising public health recommendations for the prevention of metabolic disease, the avoidance of prolonged uninterrupted periods of sedentary behavior should be considered.

  1. Elastic-Plastic Constitutive Equation of WC-Co Cemented Carbides with Anisotropic Damage

    International Nuclear Information System (INIS)

    Hayakawa, Kunio; Nakamura, Tamotsu; Tanaka, Shigekazu

    2007-01-01

    Elastic-plastic constitutive equation of WC-Co cemented carbides with anisotropic damage is proposed to predict a precise service life of cold forging tools. A 2nd rank symmetric tensor damage tensor is introduced in order to express the stress unilaterality; a salient difference in uniaxial behavior between tension and compression. The conventional framework of irreversible thermodynamics is used to derive the constitutive equation. The Gibbs potential is formulated as a function of stress, damage tensor, isotropic hardening variable and kinematic hardening variable. The elastic-damage constitutive equation, conjugate forces of damage, isotropic hardening and kinematic hardening variable is derived from the potential. For the kinematic hardening variable, the superposition of three kinematic hardening laws is employed in order to improve the cyclic behavior of the material. For the evolution equation of the damage tensor, the damage is assumed to progress by fracture of the Co matrix - WC particle interface and by the mechanism of fatigue, i.e. the accumulation of microscopic plastic strain in matrix and particles. By using the constitutive equations, calculation of uniaxial tensile and compressive test is performed and the results are compared with the experimental ones in the literature. Furthermore, finite element analysis on cold forward extrusion was carried out, in which the proposed constitutive equation was employed as die insert material

  2. Is Sedentary Lifestyle Associated With Testicular Function?

    DEFF Research Database (Denmark)

    Priskorn, Lærke; Jensen, Tina Kold; Bang, Anne Kirstine

    2016-01-01

    Based on cross-sectional data on 1,210 healthy young Danish men, we investigated whether sedentary lifestyle was associated with testicular function (semen quality and reproductive hormones) independent of physical activity. The men were invited to participate in the study between 2008 and 2012......, when they attended a compulsory medical examination to determine their fitness for military service. Information on sedentary behavior (television watching and computer time) and physical activity was obtained by questionnaire. The men had a physical examination, delivered a semen sample, and had...... ratio were detected in men watching many hours of television. Self-rated physical fitness, but not time spent on physical activity, was positively associated with sperm counts....

  3. Patterns of physical activity, sedentary behavior, and diet in U.S. adolescents.

    Science.gov (United States)

    Iannotti, Ronald J; Wang, Jing

    2013-08-01

    To identify patterns in adolescents' obesogenic behaviors and their relations to physical and psychological health. A nationally representative sample of 9,174 U.S. adolescents ages 11 to 16 years was surveyed on physical activity (PA), screen-based sedentary behavior (SB), frequency of consumption of healthy and unhealthy food items, weight status, weight control behavior, depression, physical symptoms, body dissatisfaction, overall health, and life satisfaction. Latent class analysis was used to identify patterns of PA, SB, and diet. A model with three latent classes best fit the data: Class 1 with high PA and high fruit and vegetable intake and low SB and intake of sweets, soft drinks, chips, and fries; Class 2 with high SB and high intake of sweets, soft drinks, chips, and fries; and Class 3 with low PA, low fruit and vegetable intake, and low intake of sweets, chips, and fries. Membership in the three classes was related to age, gender, race/ethnicity, and socioeconomic status. In addition, members of Class 1 (26.5%) were more likely to be of normal weight status and to fare well on most of the other health indices; of Class 2 (26.4%) were less likely to be trying to lose weight but scored poorly on the mental health indices; and of Class 3 (47.2%) were less likely to be underweight and reported greater body dissatisfaction. Three prevalent patterns of adolescent obesogenic behaviors were identified and these patterns related to weight status, depression, and other indicators of physical and psychological health. Published by Elsevier Inc.

  4. Physical Fitness, Physical Activity, Sedentary Behavior, or Diet-What Are the Correlates of Obesity in Polish School Children?

    Science.gov (United States)

    Czyż, Stanisław H; Toriola, Abel L; Starościak, Wojciech; Lewandowski, Marek; Paul, Yvonne; Oyeyemi, Adewale L

    2017-06-20

    There is substantial evidence of rising prevalence of overweight and obesity and its co-morbidities among children in western-high income developed countries. In the European Union, the prevalence of overweight and obesity is increasing fastest among Polish children. Yet, there is paucity of evidence on the relationship of behavioral factors with body weight status of children in Poland. This study examined the association of obesity with physical fitness, physical activity, sedentary behavior and diet among Polish children. A total of 641 children (10-15 years) recruited from the Lower Silesia region of Poland participated in this cross-sectional study. Participants' anthropometrics, physical fitness, physical activity, sedentary behavior and dietary intake were assessed. Outcome variables were weight categories (according to body mass index [BMI], waist-to-hip ratio [WHR], and percentage body fat [% BF]). The strongest negative correlation was found between VO₂max and %BF ( r = -0.39, p <0.05). Significant negative correlation was also found between VO₂max and weight categories ( r = -0.15). Results of the multinomial logit analysis showed that VO₂max increased in groups of overweight, normal weight and underweight children by 13%, 26% and 19%, respectively as compared to the group of obese children. VO₂max and weight and obesity indices were strongly correlated in both gender and age groups. Education and intervention programs to increase physical fitness (VO₂max) through aerobic training are recommended for Physical Education teachers, parents and children in order to reduce the rate of overweight and obesity among children in the Lower Silesia region of Poland.

  5. Stellar C III Emissions as a New Classification Parameter for (WC) Central Stars

    Science.gov (United States)

    Feibelman, W. A.

    1999-01-01

    We report detection of stellar C III lambda 1909 emission in International Ultraviolet Explorer (IUE) echelle spectra of early-type [WC] planetary nebula central stars (CSPNs). Additionally, stellar C III emission at lambda 2297 is observed in early- and late-type [WC) CSPNS. Inclusion of these C III features for abundance determinations may resolve a conflict of underabundance of C/O for early type [WC2] - [WC4] CSPNS. A linear dependence on stellar C III lambda 2297 equivalent widths can be used to indicate a new classification of type [WCUV] central stars.

  6. Age- and Sex-Specific Criterion Validity of the Health Survey for England Physical Activity and Sedentary Behavior Assessment Questionnaire as Compared With Accelerometry

    Science.gov (United States)

    Scholes, Shaun; Coombs, Ngaire; Pedisic, Zeljko; Mindell, Jennifer S.; Bauman, Adrian; Rowlands, Alex V.; Stamatakis, Emmanuel

    2014-01-01

    The criterion validity of the 2008 Physical Activity and Sedentary Behavior Assessment Questionnaire (PASBAQ) was examined in a nationally representative sample of 2,175 persons aged ≥16 years in England using accelerometry. Using accelerometer minutes/day greater than or equal to 200 counts as a criterion, Spearman's correlation coefficient (ρ) for PASBAQ-assessed total activity was 0.30 (95% confidence interval (CI): 0.25, 0.35) in women and 0.20 (95% CI: 0.15, 0.26) in men. Correlations between accelerometer counts/minute of wear time and questionnaire-assessed relative energy expenditure (metabolic equivalent-minutes/day) were higher in women (ρ = 0.41, 95% CI: 0.36, 0.46) than in men (ρ = 0.32, 95% CI: 0.26, 0.38). Similar correlations were observed for minutes/day spent in vigorous activity (women: ρ = 0.39, 95% CI: 0.33, 0.46; men: ρ = 0.31, 95% CI: 0.26, 0.36) and moderate-to-vigorous activity (women: ρ = 0.42, 95% CI: 0.36, 0.48; men: ρ = 0.38, 95% CI: 0.32, 0.45). Correlations for time spent being sedentary (physical activity was higher in older age groups, but validity was higher in younger persons for vigorous-intensity activity. The PASBAQ is a useful and valid instrument for ranking individuals according to levels of physical activity and sedentary behavior. PMID:24863551

  7. Sedentary Behavior and Sleep Duration Are Associated with Both Stress Symptoms and Suicidal Thoughts in Korean Adults.

    Science.gov (United States)

    An, Keun Ok; Jang, Jae Yong; Kim, Junghoon

    2015-12-01

    Prolonged sedentary time and sleep deprivation are associated with mental health problems such as depression and stress symptoms. Moreover, mental illness is linked with suicidal thoughts and suicide attempts. However, it is not clear whether sedentary time and sleep duration are associated with stress symptoms and suicidal thoughts independent of physical activity. Thus, our study aimed to identify if sedentary time and sleep duration were associated with both stress symptoms and suicidal thoughts. The participants in present cross-sectional study were 4,674 general Korean adults (1,938 male; 2,736 female), aged ≥ 20 years. Prolonged sedentary time (≥ 420 min/day) was significantly associated with the increased risk of stress symptoms (OR, 1.30; 95% CI, 1.04-1.62) compared with sedentary time of stress symptoms was significant for individuals who had ≤ 5 h/day of sleep time (OR, 1.88; 95% CI, 1.48-2.38) compared with sleep duration of ≥ 7 h/day. Moreover, prolonged sedentary time (OR, 1.55; 95% CI, 1.01-2.42 in ≥ 420 min/day vs. sleep duration (OR, 1.75; 95% CI, 1.17-2.62 in ≤ 5 h/day vs. ≥ 7 h/day) were significantly associated with an increased risk for suicidal thoughts after adjusting for confounding factors including physical activity. Thus, prolonged sedentary time and sleep deprivation are independently associated with both the risk of stress symptoms and suicidal thoughts. From a public health perspective, reducing sedentary time and improvement of sleep deprivation may serve as an effective strategy for preventing mental illness.

  8. Phase composition and microstructure of WC-Co alloys obtained by selective laser melting

    Science.gov (United States)

    Khmyrov, Roman S.; Shevchukov, Alexandr P.; Gusarov, Andrey V.; Tarasova, Tatyana V.

    2018-03-01

    Phase composition and microstructure of initial WC, BK8 (powder alloy 92 wt.% WC-8 wt.% Co), Co powders, ball-milled powders with four different compositions (1) 25 wt.% WC-75 wt.% Co, (2) 30 wt.% BK8-70 wt.% Co, (3) 50 wt.% WC-50 wt.% Co, (4) 94 wt.% WC-6 wt.% Co, and bulk alloys obtained by selective laser melting (SLM) from as-milled powders in as-melted state and after heat treatment were investigated by scanning electron microscopy and X-ray diffraction analysis. Initial and ball-milled powders consist of WC, hexagonal α-Co and face-centered cubic β-Co. The SLM leads to the formation of major new phases W3Co3C, W4Co2C and face-centered cubic β-Co-based solid solution. During the heat treatment, there occurs partial decomposition of the face-centered cubic β-Co-based solid solution with the formation of W2C and hexagonal α-Co solid solution. The microstructure of obtained bulk samples, in general, corresponds to the observed phase composition.

  9. Sedentary Behavior of White Collar Office Workers-Review

    OpenAIRE

    Hopkin, T. J.; Sarkar, Swarjit

    2016-01-01

    Aim The aim of this systematic review is to evaluate the physical activity time (PAT) of white collar office workers in order to assess the levels of sedentary activity in an office environment. Analysing the office workers PAT will not only allow an insight into how an office based job could impact a person’s overall health and wellness status, but will also allow for the development of future office based inter ventions aimed at increasing the overall physical activity among white collar of...

  10. Long-term sedentary work and the risk of subsite-specific colorectal cancer.

    Science.gov (United States)

    Boyle, Terry; Fritschi, Lin; Heyworth, Jane; Bull, Fiona

    2011-05-15

    Research suggests that sedentary behavior may increase the risk of some chronic diseases. The aims of the study were to examine whether sedentary work is associated with colorectal cancer and to determine whether the association differs by subsite. A total of 918 cases and 1,021 controls participated in a population-based case-control study of colorectal cancer in Western Australia in 2005-2007. Data were collected on lifestyle, physical activity, and lifetime job history. The estimated effects of sedentary work on the risk of cancers of the proximal colon, distal colon, and rectum were analyzed by using multinomial logistic regression. Compared with participants who did not spend any time in sedentary work, participants who spent 10 or more years in sedentary work had almost twice the risk of distal colon cancer (adjusted odds ratio = 1.94, 95% confidence interval: 1.28, 2.93) and a 44% increased risk of rectal cancer (adjusted odds ratio = 1.44, 95% confidence interval: 0.96, 2.18). This association was independent of recreational physical activity and was seen even among the most recreationally active participants. Sedentary work was not associated with the risk of proximal colon cancer. These results suggest that long-term sedentary work may increase the risk of distal colon cancer and rectal cancer.

  11. Dodecahedral W@WC Composite as Efficient Catalyst for Hydrogen Evolution and Nitrobenzene Reduction Reactions.

    Science.gov (United States)

    Chen, Zhao-Yang; Duan, Long-Fa; Sheng, Tian; Lin, Xiao; Chen, Ya-Feng; Chu, You-Qun; Sun, Shi-Gang; Lin, Wen-Feng

    2017-06-21

    Core-shell composites with strong phase-phase contact could provide an incentive for catalytic activity. A simple, yet efficient, H 2 O-mediated method has been developed to synthesize a mesoscopic core-shell W@WC architecture with a dodecahedral microstructure, via a one-pot reaction. The H 2 O plays an important role in the resistance of carbon diffusion, resulting in the formation of the W core and W-terminated WC shell. Density functional theory (DFT) calculations reveal that adding W as core reduced the oxygen adsorption energy and provided the W-terminated WC surface. The W@WC exhibits significant electrocatalytic activities toward hydrogen evolution and nitrobenzene electroreduction reactions, which are comparable to those found for commercial Pt/C, and substantially higher than those found for meso- and nano-WC materials. The experimental results were explained by DFT calculations based on the energy profiles in the hydrogen evolution reactions over WC, W@WC, and Pt model surfaces. The W@WC also shows a high thermal stability and thus may serve as a promising more economical alternative to Pt catalysts in these important energy conversion and environmental protection applications. The current approach can also be extended or adapted to various metals and carbides, allowing for the design and fabrication of a wide range of catalytic and other multifunctional composites.

  12. Physical activity and not sedentary time per se influences on clustered metabolic risk in elderly community-dwelling women.

    Directory of Open Access Journals (Sweden)

    Andreas Nilsson

    Full Text Available Whether amount of time spent in sedentary activities influences on clustered metabolic risk in elderly, and to what extent such an influence is independent of physical activity behavior, remain unclear. Therefore, the aim of the study was to examine cross-sectional associations of objectively assessed physical activity and sedentary behavior on metabolic risk outcomes in a sample of elderly community-dwelling women.Metabolic risk outcomes including waist circumference, systolic and diastolic blood pressures, fasting levels of plasma glucose, HDL-cholesterol and triglycerides were assessed in 120 community-dwelling older women (65-70 yrs. Accelerometers were used to retrieve daily sedentary time, breaks in sedentary time, daily time in light (LPA and moderate-to-vigorous physical activity (MVPA, and total amount of accelerometer counts. Multivariate regression models were used to examine influence of physical activity and sedentary behavior on metabolic risk outcomes including a clustered metabolic risk score.When based on isotemporal substitution modeling, replacement of a 10-min time block of MVPA with a corresponding time block of either LPA or sedentary activities was associated with an increase in clustered metabolic risk score (β = 0.06 to 0.08, p < 0.05, and an increase in waist circumference (β = 1.78 to 2.19 p < 0.01. All associations indicated between sedentary time and metabolic risk outcomes were lost once variation in total accelerometer counts was adjusted for.Detrimental influence of a sedentary lifestyle on metabolic health is likely explained by variations in amounts of physical activity rather than amount of sedentary time per se. Given our findings, increased amounts of physical activity with an emphasis on increased time in MVPA should be recommended in order to promote a favorable metabolic health profile in older women.

  13. Influence of WC addition on the microstructure and mechanical properties of NbC-Co cermets

    International Nuclear Information System (INIS)

    Huang, S.G.; Li, L.; Van der Biest, O.; Vleugels, J.

    2007-01-01

    NbC-24.5 wt.% Co cermets with up to 30 wt.% WC were obtained by solid state hot pressing at 1300 o C under a pressure of 45 MPa for 10 min and pressureless liquid phase sintering at 1360 o C for 60 min. The effect of WC addition on the microstructure and mechanical properties of NbC-Co based cermets was investigated. The hot pressed cermets exhibited interconnected and irregular niobium carbide (NbC) or (Nb,W)C grains, whereas the shape of the NbC grains changed from faceted with rounded corners to spherical, as the WC content increased in the pressureless sintered cermets. The undissolved WC increased with increasing WC addition. A clear core/rim structure was observed in the hot pressed cermets with 10-30 wt.% WC additions, whereas this structure was gradually eliminated when pressureless sintering. The hardness remains nearly constant whereas the fracture toughness slightly increases with increasing WC addition. The dissolution of WC in the Co binder and NbC grains, as well as the formation of a solid solution (Nb,W)C phase were supported by thermodynamic calculations

  14. Dietary behaviors, physical activity and sedentary lifestyle associated with overweight and obesity, and their socio-demographic correlates, among Pakistani primary school children.

    Science.gov (United States)

    Mushtaq, Muhammad Umair; Gull, Sibgha; Mushtaq, Komal; Shahid, Ubeera; Shad, Mushtaq Ahmad; Akram, Javed

    2011-11-25

    There is no data on diet- and activity-related behaviors associated with overweight and obesity among Pakistani school-aged children. The study aimed to explore dietary behaviors, physical activity and sedentary lifestyle associated with overweight and obesity, and their socio-demographic correlates, among Pakistani primary school children. A population-based cross-sectional study was conducted with a representative multistage random cluster sample of 1860 children aged five to twelve years in Lahore, Pakistan. Overweight (>+1 SD) and obesity (>+2 SD) were defined using the World Health Organization reference 2007. Chi-square test was used as the test of trend. Linear regression was used to examine the predictive power of independent variables in relation to body mass index (BMI). Logistic regression was used to quantify the independent predictors and adjusted odds ratios (aOR) with 95% confidence intervals (CI) were obtained. Statistical significance was considered at Psedentary lifestyle>one hour a day (49%) were significantly more likely to be overweight and obese while those participating in physical activity>twice a week (53%) were significantly less likely to be overweight and obese (all Psedentary lifestyle (Ptwice a week (aOR 0.49, 95% CI 0.34-0.70) and sedentary lifestyle>one hour a day (aOR 1.56, 95% CI 1.19-2.03) were independent predictors of being overweight. Skipping breakfast had independent inverse association with physical activity (aOR 0.63, 95% CI 0.45-0.89) and eating fast food and snacks had independent positive association with sedentary lifestyle (aOR 1.79, 95% CI 1.49-2.16). Female gender was independently associated with skipping breakfast (aOR 1.50, 95% CI 1.04-2.16). Male gender (aOR 1.64, 95% CI 1.33-2.02), urban area with high SES (aOR 5.09, 95% CI 3.02-8.60) and higher parental education (aOR 1.74, 95% CI 1.12-2.68) were significant independent predictors of eating fast food and snacks≥once a week. Living in the rural area was

  15. Advertisements for children's entertainment products in a popular parenting magazine: sedentary or active?

    Science.gov (United States)

    Basch, Corey H; Kecojevic, Aleksandar; Cadorett, Valerie; Basch, Charles E

    2017-01-01

    Background: The purpose of this study was to describe advertisements of children's entertainment products in a popular magazine, Parents, and to determine if they illustrated behavior that was physically active or sedentary. Methods: The sample was comprised of Parents magazines (January 2010 to December 2015). Coding involved determining if the advertisement was promoting sedentary or active behavior. Results: Nearly all of the 169 advertisements in the sample (n = 166; 97.6%) were for products that depicted sedentary behavior. The most common types of entertainment products advertised were DVDs (n = 72), plastic stacking products (n = 18), books (n=14), and electronic devices (n = 13). The most popular theme that appeared in the advertisements was the entertainment product would enhance intelligence (n = 85; 50.3%, 95% CI: 0.43-0.58). The overwhelming majority (n = 136; 80.5%. 95% CI: 0.76-0.87) of the advertisements involved the presence of a character. Conclusion: This type of advertising does not contribute to the nation's goals of increasing physical activity among youth.

  16. Obesity, sedentary lifestyle, and video games: The new thrombophilia cocktail in adolescents.

    Science.gov (United States)

    Kohorst, Mira A; Warad, Deepti M; Nageswara Rao, Amulya A; Rodriguez, Vilmarie

    2018-07-01

    Rates of venous thromboembolism have increased in the adolescent population over the last two decades, likely due to advanced diagnostics, increased use of central venous catheters, chronic medical conditions, obesity, and oral contraceptive use. Of these factors, a modifiable risk factor for adolescents is obesity. Sedentary lifestyle and prolonged immobilization are additional prothrombotic risk factors that are often associated with obesity. With ever-increasing screen time, sedentary behavior has risen accordingly, especially among gamers. We present four cases of adolescents who developed life-threatening venous thromboembolic events in the setting of obesity, sedentary lifestyle and/or immobilization, and prolonged video game use. © 2018 Wiley Periodicals, Inc.

  17. Pd enhanced WC catalyst to promote heterogeneous methane combustion

    International Nuclear Information System (INIS)

    Terracciano, Anthony Carmine; De Oliveira, Samuel; Siddhanti, Deepti; Blair, Richard; Vasu, Subith S.; Orlovskaya, Nina

    2017-01-01

    Highlights: • Pd enhanced WC catalyst particles were synthesized via mechanochemical alloying. • Catalyst was characterized by XRD, XRF, SEM, and EDS. • Catalyst was deposited on porous ZrO_2 and evaluated in heterogeneous combustion. • During combustion temperature profiles and spectral emissions were collected. - Abstract: The efficiency of combustion for low cost heat production could be greatly enhanced if an active and low cost catalyst would be used to facilitate the chemical reactions occurring during combustor operation. Within this work an experimental study of palladium (Pd) enhanced tungsten carbide (WC) catalyst, synthesized via high energy ball milling and deposited by dip coating onto a magnesia partially stabilized zirconia (MgO-ZrO_2) porous matrix of 10 ppin was evaluated in heterogeneous methane combustion. The synthesized powder was characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) coupled with Energy Dispersive Spectroscopy (EDS) analysis, as well as by X-ray Fluorescence (XRF); and the morphology of the deposited WC-Pd coating was also characterized using SEM and EDS. Performance evaluation of the heterogeneous combustor with WC-Pd coated MgO-ZrO_2 porous media was conducted at constant air flow rate and various equivalence ratios of methane/air gaseous mixtures, while monitoring axial temperature profiles within the combustion chamber using thermocouples, as well as thermal radiative and acoustic emissions from the combustor exhaust using an externally placed CCD camera and a microphone. It was found that there is a strong dependence of flame position and maximum temperature on equivalence ratio (φ) over the range of 0.47 ± 0.02 ⩽ φ ⩽ 0.75 ± 0.02. Additionally it was found that over the same equivalence ratio range, there is a characteristic 4 peak acoustic signature between 200 and 500 Hz. It was found that at higher equivalence ratios 0.51 ± 0.02 ⩽ φ ⩽ 0.75 ± 0.02 the performance of combustor

  18. Structure and hardness of a hard metal alloy prepared with a WC powder synthesized at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Costa, F.A. da [Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais, UFRN, Campus Universitario, 59072-970 Natal, RN (Brazil)], E-mail: francineac@yahoo.com; Medeiros, F.F.P. de [Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais, UFRN, Campus Universitario, 59072-970 Natal, RN (Brazil); Silva, A.G.P. da [Laboratorio de Materiais Avancados, UENF, 28015-620 Campos de Goytacazes, RJ (Brazil); Gomes, U.U. [Departamento de Fisica Teorica e Experimental, UFRN, Campus Universitario, 59072-970 Natal, RN (Brazil); Filgueira, M. [Laboratorio de Materiais Avancados, UENF, 28015-620 Campos de Goytacazes, RJ (Brazil); Souza, C.P. de [Laboratorio de Termodinamica e Reatores, UFRN, Campus Universitario, 59072-970 Natal, RN (Brazil)

    2008-06-25

    The structure and hardness of a WC-10 wt% Co alloy prepared with an experimental WC powder are compared with those of another alloy of the same composition produced under the same conditions and prepared with a commercial WC powder. The experimental WC powder was synthesized by a gas-solid reaction between APT and methane at low temperature and the commercial WC powder was conventionally produced by a solid-solid reaction between tungsten and carbon black. WC-10 wt% Co alloys with the two powders were prepared under the same conditions of milling and sintering. The structure of the sample prepared with the experimental WC powder is homogeneous and coarse grained. The structure of the sample prepared with the commercial powder is heterogeneous. Furthermore the size and shape of the WC grains are significantly different.

  19. The Impact of Family Rules on Children's Eating Habits, Sedentary Behaviors, and Weight Status.

    Science.gov (United States)

    Lederer, Alyssa M; King, Mindy H; Sovinski, Danielle; Kim, Nayoung

    2015-08-01

    Family rules may be influential in helping children to modify their dietary and sedentary behaviors, which are important modifiable risk factors for childhood obesity. However, data examining family rules in relation to children's health behaviors and weight status are limited. This cross-sectional study examined differences in family rules by demographic characteristics of students enrolled in the HEROES (Healthy, Energetic, Ready, Outstanding, Enthusiastic Schools) Initiative, a school-based childhood obesity prevention program. It also investigated the relationship between eating and screen time family rules and six eating and screen time behaviors: fast food consumption; soft drink consumption; fruit and vegetable intake; television viewing; computer use; and video game use, in addition to the association between family rules and children's weight status. Measures included self-reported behavioral data and anthropometric data from students in fourth to eighth grade at 16 schools (N=2819) in a tri-state area of the United States in spring 2012. Approximately one-third of students had each of the family rules examined. Whereas the profile of students who had specific rules varied, in general, younger, female, white, and low socioeconomic status students were more likely to have rules than their counterparts. Family rules were associated with healthier outcomes for each of the six behaviors examined (pchildren's weight status. This study demonstrates that family rules are an underutilized strategy to promote healthier eating habits and reduce children's screen time hours and may serve as an intermediary mechanism to curb childhood obesity.

  20. Physical Fitness, Physical Activity, Sedentary Behavior, or Diet—What Are the Correlates of Obesity in Polish School Children?

    Directory of Open Access Journals (Sweden)

    Stanisław H. Czyż

    2017-06-01

    Full Text Available There is substantial evidence of rising prevalence of overweight and obesity and its co-morbidities among children in western-high income developed countries. In the European Union, the prevalence of overweight and obesity is increasing fastest among Polish children. Yet, there is paucity of evidence on the relationship of behavioral factors with body weight status of children in Poland. This study examined the association of obesity with physical fitness, physical activity, sedentary behavior and diet among Polish children. A total of 641 children (10–15 years recruited from the Lower Silesia region of Poland participated in this cross-sectional study. Participants’ anthropometrics, physical fitness, physical activity, sedentary behavior and dietary intake were assessed. Outcome variables were weight categories (according to body mass index [BMI], waist-to-hip ratio [WHR], and percentage body fat [% BF]. The strongest negative correlation was found between VO2max and %BF (r = −0.39, p <0.05. Significant negative correlation was also found between VO2max and weight categories (r = −0.15. Results of the multinomial logit analysis showed that VO2max increased in groups of overweight, normal weight and underweight children by 13%, 26% and 19%, respectively as compared to the group of obese children. VO2max and weight and obesity indices were strongly correlated in both gender and age groups. Education and intervention programs to increase physical fitness (VO2max through aerobic training are recommended for Physical Education teachers, parents and children in order to reduce the rate of overweight and obesity among children in the Lower Silesia region of Poland.

  1. Project SHINE: Effects of Parent–Adolescent Communication on Sedentary Behavior in African American Adolescents

    Science.gov (United States)

    Wilson, Dawn K.; Schneider, Elizabeth M.; Alia, Kassandra A.

    2013-01-01

    Objective This study examined parenting variables (communication, monitoring) as moderators of a family-based intervention for reducing sedentary behavior (SB) in African American adolescents. As a secondary aim, a similar model was tested using adolescent weight status as the outcome. Methods African American adolescents (n = 73; 12.45 ± 1.45 years; 60% girls; 63% overweight/obese) and caregivers were randomized to a 6-week interactive, parent-based intervention or general health condition. Parent–adolescent communication and monitoring of health behaviors were self-reported by parents. Adolescent SB was self-reported by youth. Results There was a significant intervention by communication interaction, such that intervention families with more positive communication showed lower adolescent SB than those with less positive communication or those in the comparison condition. No effects were found for monitoring on SB or for the model with weight status as the outcome. Conclusions Parent–adolescent communication may be an effective component to integrate into health promotion programs for African American adolescents. PMID:23685450

  2. Replacing sedentary time with physical activity: a 15-year follow-up of mortality in a national cohort

    Directory of Open Access Journals (Sweden)

    Dohrn IM

    2018-01-01

    Full Text Available Ing-Mari Dohrn,1 Lydia Kwak,2 Pekka Oja,3 Michael Sjöström,4 Maria Hagströmer1,5 1Department of Neurobiology, Care Sciences and Society (NVS, 2Institute of Environmental Medicine (IMM, Karolinska Institutet, Stockholm, Sweden; 3UKK Institute, Tampere, Finland; 4Department of Biosciences and Nutrition (BioNut, Karolinska Institutet, 5Functional Area Occupational Therapy and Physiotherapy, Karolinska University Hospital, Stockholm, Sweden Background: Sedentary behavior is associated with health risks in adults. The potential benefits of reducing sedentary time may be dependent not only on decrease per se, but also on the type of activity it replaces. Few longitudinal studies have investigated the effects on mortality when replacing objectively assessed sedentary time with another physical activity (PA behavior. Objective: To investigate the effects of replacing objectively assessed sedentary time with time in light-intensity PA or moderate-vigorous PA (MVPA on all-cause mortality, cardiovascular disease (CVD mortality or cancer mortality in a cohort with 15 years follow-up time.Methods: In total, 851 women and men from the population-based Sweden Attitude Behaviour and Change study were included. Time spent sedentary, in light-intensity PA and in MVPA were assessed using an Actigraph 7164 accelerometer. Mortality data were obtained from Swedish registers. Cox proportional hazards models estimated hazard ratios (HR of mortality with 95% confidence intervals (CI and isotemporal substitution models were used to estimate the effect of replacing sedentary behavior with PA for the same amount of time.Results: Over a follow-up of 14.2 years (SD 1.9 with 12,117 person-years at risk, 79 deaths occurred, 24 deaths from CVD, 27 from cancer, and 28 from other causes. Replacing 30 minutes/day of sedentary time with light-intensity PA was associated with significant reduction in all-cause mortality risk (HR: 0.89, 95% CI: 0.81-0.98 and CVD mortality risk (HR

  3. Is there an association among actual motor competence, perceived motor competence, physical activity, and sedentary behavior in preschool children?

    OpenAIRE

    Lopes, Vítor P.; Barnett, L.M.; Rodrigues, Luis Paulo

    2016-01-01

    The purpose is to explore relationships among moderate to vigorous physical activity (MVPA), sedentary behavior (SB), and actual gross motor competence (MC) and perceived motor competence (PMC) in young children. Data were collected in 101 children (M age = 4.9 ± 0.93 years). MVPA was measured with accelerometry. Gross MC was assessed with the Portuguese version of the Movement Assessment Battery for Children. PMC was evaluated with the Pictorial Scale of Perceived Competence and Social Accep...

  4. Sedentary and active: self-reported sitting time among marathon and half-marathon participants.

    Science.gov (United States)

    Whitfield, Geoffrey; Pettee Gabriel, Kelley K; Kohl, Harold William

    2014-01-01

    Emerging evidence suggests that combined physical activity (PA) and inactivity may be more important for chronic disease risk than PA alone. A highly active yet highly sedentary population is needed to study this interaction. The present purpose is to describe the sitting habits of a group of recreational runners and determine if sitting varies with reported training duration or anticipated running velocity. Marathon and half-marathon participants completed the Multicontext Sitting Time Questionnaire and reported peak training duration, anticipated finishing time, and demographic information. Sitting time was described across 5 contexts for workdays and nonworkdays. Total sitting time was analyzed by tertiles of training duration and anticipated event running velocity. 218 participants took part in this study. Median reported training time was 6.5 hours per week. Median total sitting time was higher on workdays than nonworkdays (645 and 480 minutes, respectively, P training duration or anticipated event running velocity. These results suggest that recreational distance runners are simultaneously highly sedentary and highly active, supporting independence of sedentary behaviors and moderate- to vigorous-intensity PA. This population may provide the characteristics needed to study the joint effects of active and sedentary behaviors on health outcomes.

  5. Gene number determination and genetic polymorphism of the gamma delta T cell co-receptor WC1 genes

    Directory of Open Access Journals (Sweden)

    Chen Chuang

    2012-10-01

    Full Text Available Abstract Background WC1 co-receptors belong to the scavenger receptor cysteine-rich (SRCR superfamily and are encoded by a multi-gene family. Expression of particular WC1 genes defines functional subpopulations of WC1+ γδ T cells. We have previously identified partial or complete genomic sequences for thirteen different WC1 genes through annotation of the bovine genome Btau_3.1 build. We also identified two WC1 cDNA sequences from other cattle that did not correspond to sequences in the Btau_3.1 build. Their absence in the Btau_3.1 build may have reflected gaps in the genome assembly or polymorphisms among animals. Since the response of γδ T cells to bacterial challenge is determined by WC1 gene expression, it was critical to understand whether individual cattle or breeds differ in the number of WC1 genes or display polymorphisms. Results Real-time quantitative PCR using DNA from the animal whose genome was sequenced (“Dominette” and sixteen other animals representing ten breeds of cattle, showed that the number of genes coding for WC1 co-receptors is thirteen. The complete coding sequences of those thirteen WC1 genes is presented, including the correction of an error in the WC1-2 gene due to mis-assembly in the Btau_3.1 build. All other cDNA sequences were found to agree with the previous annotation of complete or partial WC1 genes. PCR amplification and sequencing of the most variable N-terminal SRCR domain (domain 1 which has the SRCR “a” pattern of each of the thirteen WC1 genes showed that the sequences are highly conserved among individuals and breeds. Of 160 sequences of domain 1 from three breeds of cattle, no additional sequences beyond the thirteen described WC1 genes were found. Analysis of the complete WC1 cDNA sequences indicated that the thirteen WC1 genes code for three distinct WC1 molecular forms. Conclusion The bovine WC1 multi-gene family is composed of thirteen genes coding for three structural forms whose

  6. Can sedentary behavior be made more active? A randomized pilot study of TV commercial stepping versus walking

    Directory of Open Access Journals (Sweden)

    Steeves Jeremy A

    2012-08-01

    Full Text Available Abstract Background There is a growing problem of physical inactivity in America, and approximately a quarter of the population report being completely sedentary during their leisure time. In the U.S., TV viewing is the most common leisure-time activity. Stepping in place during TV commercials (TV Commercial Stepping could increase physical activity. The purpose of this study was to examine the feasibility of incorporating physical activity (PA into a traditionally sedentary activity, by comparing TV Commercial Stepping during 90 min/d of TV programming to traditional exercise (Walking. Methods A randomized controlled pilot study of the impact of 6 months of TV Commercial Stepping versus Walking 30 min/day in adults was conducted. 58 sedentary, overweight (body mass index 33.5 ± 4.8 kg/m2 adults (age 52.0 ± 8.6 y were randomly assigned to one of two 6-mo behavioral PA programs: 1 TV Commercial Stepping; or 2 Walking 30 min/day. To help facilitate behavior changes participants received 6 monthly phone calls, attended monthly meetings for the first 3 months, and received monthly newsletters for the last 3 months. Using intent-to-treat analysis, changes in daily steps, TV viewing, diet, body weight, waist and hip circumference, and percent fat were compared at baseline, 3, and 6 mo. Data were collected in 2010–2011, and analyzed in 2011. Results Of the 58 subjects, 47 (81% were retained for follow-up at the completion of the 6-mo program. From baseline to 6-mo, both groups significantly increased their daily steps [4611 ± 1553 steps/d vs. 7605 ± 2471 steps/d (TV Commercial Stepping; 4909 ± 1335 steps/d vs. 7865 ± 1939 steps/d (Walking; P  Conclusions Participants in both the TV Commercial Stepping and Walking groups had favorable changes in daily steps, TV viewing, diet, and anthropometrics. PA can be performed while viewing TV commercials and this may be a feasible alternative to traditional approaches for

  7. A qualitative examination of the perceptions of parents on the Canadian Sedentary Behaviour Guidelines for the early years.

    Science.gov (United States)

    Carson, Valerie; Clark, Marianne; Berry, Tanya; Holt, Nicholas L; Latimer-Cheung, Amy E

    2014-05-17

    Minimizing sedentary behavior, in particular screen-based sedentary behavior, during the early years is important for healthy growth and development. Consequently, new Canadian Sedentary Behaviour Guidelines for the Early Years (aged 0-4 years) were recently released. Researchers are unclear what messages should supplement the guidelines when disseminating them to parents and when using the guidelines in behaviour-change interventions to increase adoption. The objective of this study was to qualitatively examine parents' perceptions of the new Canadian Sedentary Behaviour Guidelines for the Early Years. Parents with a child ≤4 years who attended a child care centre were purposefully recruited from child care centres. A total of 7 semi-structured focus groups with 2 to 5 parents were conducted from August to November, 2013 by a trained and experienced moderator. Participants were asked a series of open-ended questions pertaining to the Sedentary Behaviour Guidelines information sheet. Initial themes were identified followed by further review and analysis. For the most part parents thought the guidelines were clear and did not disagree with the recommendations per se. However, some confusion arose around the value of some sedentary activities, such as reading and coloring, for social and cognitive development. Many parents described feeling guilty after reading the guidelines and perceived several barriers in meeting the daily recommendations. Common barriers included the need to balance multiple demands of family life, the prevalence and accessibility of screen technology, and the weather and built environment where families live. Parents expressed the importance of communicating the guidelines early enough for good habits to be established and the need for realistic strategies and ideas to help them meet the recommendations. Overall the findings indicate that gain-framed messages around the role of screen-based and non-screen-based sedentary behavior for children

  8. [Food consumption in children and youth: effect of sedentary activities].

    Science.gov (United States)

    Thivel, D; Chaput, J P

    2013-08-01

    Sedentary behavior has progressed with modern society, generating very low levels of energy expenditure and subsequent body weight disorders (obesity). There is also evidence that the absence of physical activity associated with short sleep time and watching television or playing video games leads to poor eating habits and favors high-energy intake. These findings have generally been reported in adults, with a few studies including data on children and adolescents. This brief review summarizes the current literature regarding the impact of such activities on food consumption and eating behavior in children and adolescents. There appears to be an uncoupling effect dissociating these activities from the sensation of hunger and thus energy intake. Children and adolescents seem to increase their energy intake during and after such activities without any alteration of their subjective appetite. In addition to considering the impact of sedentary behavior and physical activity level, future public health recommendations should also focus on associated nutritional adaptations (energy balance). Copyright © 2013. Published by Elsevier Masson SAS.

  9. Reconsidering the sedentary behaviour paradigm.

    Directory of Open Access Journals (Sweden)

    Carol Maher

    Full Text Available AIMS: Recent literature has posed sedentary behaviour as an independent entity to physical inactivity. This study investigated whether associations between sedentary behaviour and cardio-metabolic biomarkers remain when analyses are adjusted for total physical activity. METHODS: Cross-sectional analyses were undertaken on 4,618 adults from the 2003/04 and 2005/06 U.S. National Health and Nutrition Examination Survey. Minutes of sedentary behaviour and moderate-to-vigorous physical activity (MVPA, and total physical activity (total daily accelerometer counts minus counts accrued during sedentary minutes were determined from accelerometry. Associations between sedentary behaviour and cardio-metabolic biomarkers were examined using linear regression. RESULTS: Results showed that sedentary behaviour was detrimentally associated with 8/11 cardio-metabolic biomarkers when adjusted for MVPA. However, when adjusted for total physical activity, the associations effectively disappeared, except for C-reactive protein, which showed a very small, favourable association (β = -0.06 and triglycerides, which showed a very small, detrimental association (β = 0.04. Standardised betas suggested that total physical activity was consistently, favourably associated with cardio-metabolic biomarkers (9/11 biomarkers, standardized β = 0.08-0.30 while sedentary behaviour was detrimentally associated with just 1 biomarker (standardized β = 0.12. CONCLUSION: There is virtually no association between sedentary behaviour and cardio-metabolic biomarkers once analyses are adjusted for total physical activity. This suggests that sedentary behaviour may not have health effects independent of physical activity.

  10. THE STRUCTURE AND PROPERTIES OF COMPOSITE LASER CLAD COATINGS WITH Ni BASED MATRIX WITH WC PARTICLES

    Directory of Open Access Journals (Sweden)

    Zita Iždinská

    2010-09-01

    Full Text Available In this work, the influence of the processing conditions on the microstructure and abrasive wear behavior of composite laser clad coatings with Ni based matrix reinforced with 50% WC particles is analyzed. Composite powder was applied in the form of coatings onto a mild steel substrate (Fe–0.17% C by different laser powers and cladding speeds. The microstructure of the coatings was analyzed by scanning electron microscopy (SEM. Tribological properties of coatings were evaluated by pin-on-disc wear test. It appeared that the hardness of the matrix of composite coatings decreases with increasing cladding speed. However, wear resistance of composite coatings with decreasing hardness of Ni based matrix increases. Significantly enhanced wear resistance of WC composite coatings in comparison with Ni based coatings is attributed to the hard phase structures in composite coatings.

  11. Improvement of Surface Properties of Inconel718 by HVOF Coating with WC-Metal Powder and by Laser Heat Treatment of the Coating

    Directory of Open Access Journals (Sweden)

    Hui Gon Chun

    2015-01-01

    Full Text Available High-velocity oxygen-fuel (HVOF thermal spray coating with WC-metal powder was carried out by using optimal coating process on an Inconel718 surface for improvement of the surface properties, friction, wear, and corrosion resistance. Binder metals such as Cr and Ni were completely melted and WC was decomposed partially to W2C and graphite during the high temperature (up to 3500°C thermal spraying. The melted metals were bonded with WC and other carbides and were formed as WC-metal coating. The graphite and excessively sprayed oxygen formed carbon oxide gases, and these gases formed porous coating by evolution of the gases. The surface properties were improved by HVOF coating and were improved further by CO2 laser heat treatment (LH. Wear resistance of In718 surface was improved by coating and LH at 25°C and an elevated temperature of 450°C, resulting in reduction of wear trace traces, and was further improved by LH of the coating in reducing wear depth. Corrosion resistance due to coating in sea water was improved by LH. HVOF coating of WC-metal powder on a metal surface and a LH of the coating were highly recommended for the improvement of In718 surface properties, the friction behavior, and wear resistance.

  12. WC1 is a hybrid γδ TCR coreceptor and pattern recognition receptor for pathogenic bacteria.

    Science.gov (United States)

    Hsu, Haoting; Chen, Chuang; Nenninger, Ariel; Holz, Lauren; Baldwin, Cynthia L; Telfer, Janice C

    2015-03-01

    WC1 proteins are uniquely expressed on γδ T cells and belong to the scavenger receptor cysteine-rich (SRCR) superfamily. While present in variable, and sometimes high, numbers in the genomes of mammals and birds, in cattle there are 13 distinct genes (WC1-1 to WC1-13). All bovine WC1 proteins can serve as coreceptors for the TCR in a tyrosine phosphorylation dependent manner, and some are required for the γδ T cell response to Leptospira. We hypothesized that individual WC1 receptors encode Ag specificity via coligation of bacteria with the γδ TCR. SRCR domain binding was directly correlated with γδ T cell response, as WC1-3 SRCR domains from Leptospira-responsive cells, but not WC1-4 SRCR domains from Leptospira-nonresponsive cells, bound to multiple serovars of two Leptospira species, L. borgpetersenii, and L. interrogans. Three to five of eleven WC1-3 SRCR domains, but none of the eleven WC1-4 SRCR domains, interacted with Leptospira spp. and Borrelia burgdorferi, but not with Escherichia coli or Staphylococcus aureus. Mutational analysis indicated that the active site for bacterial binding in one of the SRCR domains is composed of amino acids in three discontinuous regions. Recombinant WC1 SRCR domains with the ability to bind leptospires inhibited Leptospira growth. Our data suggest that WC1 gene arrays play a multifaceted role in the γδ T cell response to bacteria, including acting as hybrid pattern recognition receptors and TCR coreceptors, and they may function as antimicrobials. Copyright © 2015 by The American Association of Immunologists, Inc.

  13. Television Viewing and Its Association with Sedentary Behaviors, Self-Rated Health and Academic Performance among Secondary School Students in Peru

    OpenAIRE

    Bimala Sharma; Rosemary Cosme Chavez; Ae Suk Jeong; Eun Woo Nam

    2017-01-01

    The study assessed television viewing >2 h a day and its association with sedentary behaviors, self-rated health, and academic performance among secondary school adolescents. A cross-sectional survey was conducted among randomly selected students in Lima in 2015. We measured self-reported responses of students using a standard questionnaire, and conducted in-depth interviews with 10 parents and 10 teachers. Chi-square test, correlation and multivariate logistic regression analysis were per...

  14. Psychosocial and Environmental Correlates of Sedentary Behaviors in Spanish Children

    Directory of Open Access Journals (Sweden)

    S. Aznar

    2017-01-01

    Full Text Available Purpose. To evaluate children’s psychosocial and environmental factors associated with sedentary behavior (SB. Method. The study involved a total of 420 children (mean 9.2 years; 52.9% girls from the community of Madrid, Spain. SB and physical activity (PA were objectively measured using accelerometers. TV viewing and potential correlates were assessed by questionnaire. Mixed-model regression analysis, adjusted for clustering within school locations, evaluated the relation of each independent variable with SBs. Results. Girls showed higher levels of SB than boys, whereas boys reported more TV viewing (p<.001 in all cases. Regression analysis showed that MVPA levels were negatively related to objective SB measurement in both boys and girls (p<.001. Parent and friend support to PA were negatively associated with SB on weekdays in boys and girls, respectively (p<.05. In the boys’ group, parental professional level was a positive predictor of SB on weekend days (p=.011. Boys with more positive neighborhood perceptions spent less time watching TV (p<.001, whereas mother’s leisure-time PA level was a negative correlate of TV viewing in girls’ group (p<.01. Conclusion. Different psychosocial and environmental correlates of SB were identified. Present findings are promising targets for interventions to improve children’s health.

  15. Body Mass Index: Accounting for Full Time Sedentary Occupation and 24-Hr Self-Reported Time Use

    OpenAIRE

    Tudor-Locke, Catrine; Schuna, John M.; Katzmarzyk, Peter T.; Liu, Wei; Hamrick, Karen S.; Johnson, William D.

    2014-01-01

    Objectives We used linked existing data from the 2006–2008 American Time Use Survey (ATUS), the Current Population Survey (CPS, a federal survey that provides on-going U.S. vital statistics, including employment rates) and self-reported body mass index (BMI) to answer: How does BMI vary across full time occupations dichotomized as sedentary/non-sedentary, accounting for time spent in sleep, other sedentary behaviors, and light, moderate, and vigorous intensity activities? Methods We classifie...

  16. Small-sized and contacting Pt-WC nanostructures on graphene as highly efficient anode catalysts for direct methanol fuel cells.

    Science.gov (United States)

    Wang, Ruihong; Xie, Ying; Shi, Keying; Wang, Jianqiang; Tian, Chungui; Shen, Peikang; Fu, Honggang

    2012-06-11

    The synergistic effect between Pt and WC is beneficial for methanol electro-oxidation, and makes Pt-WC catalyst a promising anode candidate for the direct methanol fuel cell. This paper reports on the design and synthesis of small-sized and contacting Pt-WC nanostructures on graphene that bring the synergistic effect into full play. Firstly, DFT calculations show the existence of a strong covalent interaction between WC and graphene, which suggests great potential for anchoring WC on graphene with formation of small-sized, well-dispersed WC particles. The calculations also reveal that, when Pt attaches to the pre-existing WC/graphene hybrid, Pt particles preferentially grow on WC rather than graphene. Our experiments confirmed that highly disperse WC nanoparticles (ca. 5 nm) can indeed be anchored on graphene. Also, Pt particles 2-3 nm in size are well dispersed on WC/graphene hybrid and preferentially grow on WC grains, forming contacting Pt-WC nanostructures. These results are consistent with the theoretical findings. X-ray absorption fine structure spectroscopy further confirms the intimate contact between Pt and WC, and demonstrates that the presence of WC can facilitate the crystallinity of Pt particles. This new Pt-WC/graphene catalyst exhibits a high catalytic efficiency toward methanol oxidation, with a mass activity 1.98 and 4.52 times those of commercial PtRu/C and Pt/C catalysts, respectively. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Effects of physical activity and sedentary time on the risk of heart failure.

    Science.gov (United States)

    Young, Deborah Rohm; Reynolds, Kristi; Sidell, Margo; Brar, Somjot; Ghai, Nirupa R; Sternfeld, Barbara; Jacobsen, Steven J; Slezak, Jeffrey M; Caan, Bette; Quinn, Virginia P

    2014-01-01

    Although the benefits of physical activity for risk of coronary heart disease are well established, less is known about its effects on heart failure (HF). The risk of prolonged sedentary behavior on HF is unknown. The study cohort included 82 695 men aged≥45 years from the California Men's Health Study without prevalent HF who were followed up for 10 years. Physical activity, sedentary time, and behavioral covariates were obtained from questionnaires, and clinical covariates were determined from electronic medical records. Incident HF was identified through International Classification of Diseases, Ninth Revision codes recorded in electronic records. During a mean follow-up of 7.8 years (646 989 person-years), 3473 men were diagnosed with HF. Controlling for sedentary time, sociodemographics, hypertension, diabetes mellitus, unfavorable lipid levels, body mass index, smoking, and diet, the hazard ratio (95% confidence interval [CI]) of HF in the lowest physical activity category compared with those in the highest category was 1.52 (95% CI, 1.39-1.68). Those in the medium physical activity category were also at increased risk (hazard ratio, 1.17 [95% CI, 1.06-1.29]). Controlling for the same covariates and physical activity, the hazard ratio (95% CI) of HF in the highest sedentary category compared with the lowest was 1.34 (95% CI, 1.21-1.48). Medium sedentary time also conveyed risk (hazard ratio, 1.13 [95% CI, 1.04-1.24]). Results showed similar trends across white and Hispanic subgroups, body mass index categories, baseline hypertension status, and prevalent coronary heart disease. Both physical activity and sedentary time may be appropriate intervention targets for preventing HF.

  18. The relationship between cell phone use, physical and sedentary activity, and cardiorespiratory fitness in a sample of U.S. college students.

    Science.gov (United States)

    Lepp, Andrew; Barkley, Jacob E; Sanders, Gabriel J; Rebold, Michael; Gates, Peter

    2013-06-21

    Today's cell phones increase opportunities for activities traditionally defined as sedentary behaviors (e.g., surfing the internet, playing video games). People who participate in large amounts of sedentary behaviors, relative to those who do not, tend to be less physically active, less physically fit, and at greater risk for health problems. However, cell phone use does not have to be a sedentary behavior as these devices are portable. It can occur while standing or during mild-to-moderate intensity physical activity. Thus, the relationship between cell phone use, physical and sedentary activity, and physical fitness is unclear. The purpose of this study was to investigate these relationships among a sample of healthy college students. Participants were first interviewed about their physical activity behavior and cell phone use. Then body composition was assessed and the validated self-efficacy survey for exercise behaviors completed. This was followed by a progressive exercise test on a treadmill to exhaustion. Peak oxygen consumption (VO2 peak) during exercise was used to measure cardiorespiratory fitness. Hierarchical regression was used to assess the relationship between cell phone use and cardiorespiratory fitness after controlling for sex, self-efficacy, and percent body fat. Interview data was transcribed, coded, and Chi-square analysis was used to compare the responses of low and high frequency cell phone users. Cell phone use was significantly (p = 0.047) and negatively (β = -0.25) related to cardio respiratory fitness independent of sex, self-efficacy, and percent fat which were also significant predictors (p cell phone use indicated a broader pattern of sedentary behaviors apart from cell phone use, such as watching television. Cell phone use, like traditional sedentary behaviors, may disrupt physical activity and reduce cardiorespiratory fitness.

  19. Identifying developmental trajectories of body mass index in childhood using latent class growth (mixture) modelling : associations with dietary, sedentary and physical activity behaviors: a longitudinal study

    NARCIS (Netherlands)

    Koning, Maaike; Hoekstra, Trynke; de Jong, Elske; Visscher, Tommy L.S.; Seidell, Jacob C.; Renders, Carry M.

    2016-01-01

    BACKGROUND: To date, many epidemiologic studies examining associations between obesity and dietary and sedentary/physical activity behaviors have focused on assessing Body Mass Index (BMI) at one point in time. Recent developments in statistical techniques make it possible to study the potential

  20. Physical Activity and Sedentary Behavior in an Ethnically Diverse Group of South African School Children

    Directory of Open Access Journals (Sweden)

    Joanne McVeigh, Rebecca Meiring

    2014-06-01

    Full Text Available Few studies have examined physical activity and inactivity levels in an urban South African setting across 12 years of formal schooling. This information is important for implementing strategies to curb increasing trends of physical inactivity and related negative consequences, especially in low to middle income countries facing multiple challenges on overburdened health care systems. We examined levels of physical activity and sedentary behaviour cross-sectionally over 12 school years from childhood to adolescence in Black, White and Indian boys and girls. The aim of our study was to describe gender and race related patterns of physical and sedentary activity levels in a sample of South African children and to determine whether there were associations between these variables and body mass status. Physical activity questionnaires, previously validated in a South African setting, were used to gather information about activity and sedentary behaviours among 767 Black, White and Indian children (5-18 years of age across the 12 grades of formal schooling. Body mass and height were also measured. Time spent in moderate-vigorous physical activity declined over the school years for all race groups and was consistently lower for girls than boys (p = 0.03, while time spent in sedentary activity increased with increasing grade (p 0.05 whereas time spent in sedentary activities was significantly and positively correlated with body mass across all race groups: Indian (r = 0.25, p < 0.001, White (r = 0.22, p < 0.001 and Black (r = 0.37, p = 0.001. The strength of the associations was similar for boys and girls. Black and Indian children were less physically active than their white peers (p < 0.05, and Black children also spent more time in sedentary activity (p < 0.05. Additionally, Black children had the highest proportion of overweight participants (30%, and Indian children the most number of underweight children (13%. Regardless of ethnicity, children who

  1. Physical Activity and Sedentary Behavior Associated with Components of Metabolic Syndrome among People in Rural China.

    Science.gov (United States)

    Xiao, Jing; Shen, Chong; Chu, Min J; Gao, Yue X; Xu, Guang F; Huang, Jian P; Xu, Qiong Q; Cai, Hui

    2016-01-01

    Metabolic syndrome is prevalent worldwide and its prevalence is related to physical activity, race, and lifestyle. Little data is available for people living in rural areas of China. In this study we examined associations of physical activity and sedentary behaviors with metabolic syndrome components among people in rural China. The Nantong Metabolic Syndrome Study recruited 13,505 female and 6,997 male participants between 2007 and 2008. Data of socio-demographic characteristics and lifestyle were collected. The associations of physical activity and sedentary behaviors with metabolic syndrome components were analyzed. Prevalence of metabolic syndrome was 21.6%. It was significantly lower in men than in women. Low risks of metabolic syndrome were observed in those who did less sitting and engaged in more vigorous physical activity. The highest tertile of vigorous physical activity was associated with 15-40% decreased odds of metabolic syndrome and all of its components, except for low high-density lipoprotein cholesterol in men. Women with the highest tertile of moderate physical activity had 15-30% lower odds of central obesity, high glucose, and high triglycerides compared with those in the lowest tertile. Sitting time >42 hours per week had a 4%-12% attributable risk of metabolic syndrome, central obesity, and high triglycerides in both genders, and abnormal glucose and diastolic blood pressure in women. Sleeping for more than 8 hours per day was associated with risk of high serum glucose and lipids. Our data suggested that physical activity has a preventive effect against metabolic syndrome and all its abnormal components, and that longer sitting time and sleep duration are associated with an increased risk of metabolic syndrome components, including central obesity and high triglycerides, glucose, and diastolic blood pressure. This study could provide information for future investigation into these associations. Also, recommendations are developed to reduce

  2. Screen-based sedentary behaviors, mental health, and social relationships among adolescents

    Directory of Open Access Journals (Sweden)

    Danilo R Silva

    2018-01-01

    Full Text Available Abstract Aim: To analyze the association between screen-based sedentary behaviors, mental health, and social relationships in Brazilian adolescents. Methods: A representative sample of the adolescents from Londrina/PR was selected (n = 1,158; 10 to 17 y. Weekday and weekend screen time (TV-viewing and computer/video-game, mental health indicators (self-rated health, stress, feelings of sadness, and satisfaction with own body, and perceived social relationships (friends, family, and teachers were collected through questionnaires. Somatic maturation, body mass index, and physical activity were assessed as covariates. Results: Adolescents who reported higher TV-viewing presented higher odds (p < 0.05 for poor self-rated health (boys, higher stress (both sexes, and dissatisfaction with own body (boys, friendships (girls, and teachers (girls. In contrast, higher computer/video-game use was associated with lower odds (p < 0.05 for poor self-rated health (girls, higher stress (boys, feelings of sadness (both sexes, and dissatisfaction with friends (both sexes and family (both sexes. Conclusion: While higher TV-viewing is associated with negative outcomes, higher computer/video-game users demonstrate better mental health and lower satisfaction with their social relationships.

  3. Energy expenditure during common sitting and standing tasks: examining the 1.5 MET definition of sedentary behaviour.

    Science.gov (United States)

    Mansoubi, Maedeh; Pearson, Natalie; Clemes, Stacy A; Biddle, Stuart Jh; Bodicoat, Danielle H; Tolfrey, Keith; Edwardson, Charlotte L; Yates, Thomas

    2015-05-29

    Sedentary behavior is defined as any waking behavior characterized by an energy expenditure of 1.5 METS or less while in a sitting or reclining posture. This study examines this definition by assessing the energy cost (METs) of common sitting, standing and walking tasks. Fifty one adults spent 10 min during each activity in a variety of sitting tasks (watching TV, Playing on the Wii, Playing on the PlayStation Portable (PSP) and typing) and non-sedentary tasks (standing still, walking at 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, and 1.6 mph). Activities were completed on the same day in a random order following an assessment of resting metabolic rate (RMR). A portable gas analyzer was used to measure oxygen uptake, and data were converted to units of energy expenditure (METs). Average of standardized MET values for screen-based sitting tasks were: 1.33 (SD: 0.24) METS (TV), 1.41 (SD: 0.28) (PSP), and 1.45 (SD: 0.32) (Typing). The more active, yet still seated, games on the Wii yielded an average of 2.06 (SD: 0.5) METS. Standing still yielded an average of 1.59 (SD: 0.37) METs. Walking MET values increased incrementally with speed from 2.17 to 2.99 (SD: 0.5 - 0.69) METs. The suggested 1.5 MET threshold for sedentary behaviors seems reasonable however some sitting based activities may be classified as non-sedentary. The effect of this on the definition of sedentary behavior and associations with metabolic health needs further investigation.

  4. Children’s sedentary behaviour: descriptive epidemiology and associations with objectively-measured sedentary time

    OpenAIRE

    Klitsie, Tessa; Corder, Kirsten; Visscher, Tommy LS; Atkin, Andrew J; Jones, Andrew P; van Sluijs, Esther MF

    2013-01-01

    Background: Little is known regarding the patterning and socio-demographic distribution of multiple sedentary behaviours in children. The aims of this study were to: 1) describe the leisure-time sedentary behaviour of 9-10 year old British children, and 2) establish associations with objectively-measured sedentary time. Methods. Cross-sectional analysis in the SPEEDY study (Sport, Physical activity and Eating behaviour: Environmental Determinants in Young people) (N=1513, 44.3% boys). Twelve ...

  5. Pt catalysts on PANI coated WC/C nanocomposites for methanol electro-oxidation and oxygen electro-reduction in DMFC

    International Nuclear Information System (INIS)

    Yaldagard, Maryam; Jahanshahi, Mohsen; Seghatoleslami, Naser

    2014-01-01

    Highlights: • In this work nanosized WC/C were successfully coated by PANI. • Pt particles (10.56 nm) were uniformly dispersed on the surface of PANI/WC/C support. • The Pt/PANI/WC/C exhibited higher MOR activity and CO tolerance than Pt/C. • The Pt/PANI/WC/C exhibited higher activity for ORR than Pt/C in RDE experiments. • Pt/PANI/WC/C showed good stability than that of Pt/C in the presence of methanol. - Abstract: In the present study a Pt/PANI/WC/C electrocatalyst was developed to increase the methanol electro-oxidation and oxygen electro-reduction activity and stability of commercial Pt/C electrocatalyst. WC/C was coated with protonated polyaniline (PANI) in situ during the polymerization of aniline. Fourier transform infrared (FTIR) results illustrate the presence of PANI in the composite. The conductivity of PANI coated – WC/C has been compared with the conductivity of the corresponding mixtures of WC/C and Vulcan XC-72. X-ray diffraction results showed that Pt particles were dispersed on the support with mean particle size of about 10.56 nm. Transition electron microscopy images showed that the nanosized WC/C were successfully coated by PANI. Based on the electrochemical properties characterized by cyclic voltammetry, CO stripping and rotating disk electrode measurements it was found that the as prepared Pt/PANI/WC/C electrocatalyst exhibited a comparable activity for methanol oxidation reaction and oxygen reduction reaction with respect to the commercial one. A significant reduction in the potential of CO electro-oxidation peak from 0.75 V for Pt/C to 0.52 V for Pt/PANI/WC/C electrocatalyst indicates that an increase in the activity for CO electro-oxidation is achieved by replacing the carbon support by PANI coated WC/C. Chronoamerometry results also showed, in the presence of methanol the Pt/PANI/WC/C electrocatalyst still maintains a higher current density than Pt/WC/C and Pt/C

  6. Pt catalysts on PANI coated WC/C nanocomposites for methanol electro-oxidation and oxygen electro-reduction in DMFC

    Energy Technology Data Exchange (ETDEWEB)

    Yaldagard, Maryam, E-mail: m_yaldagard@yahoo.com [Department of Chemical Engineering, Ferdowsi University of Mashhad, P.O. Box 91775-1111 (Iran, Islamic Republic of); Nanotechnology Research Institute, School of Chemical Engineering, Babol University of Technology (Iran, Islamic Republic of); Jahanshahi, Mohsen, E-mail: mjahan@nit.um.ac.ir [Nanotechnology Research Institute, School of Chemical Engineering, Babol University of Technology (Iran, Islamic Republic of); Seghatoleslami, Naser, E-mail: Slami@um.ac.ir [Department of Chemical Engineering, Ferdowsi University of Mashhad, P.O. Box 91775-1111 (Iran, Islamic Republic of)

    2014-10-30

    Highlights: • In this work nanosized WC/C were successfully coated by PANI. • Pt particles (10.56 nm) were uniformly dispersed on the surface of PANI/WC/C support. • The Pt/PANI/WC/C exhibited higher MOR activity and CO tolerance than Pt/C. • The Pt/PANI/WC/C exhibited higher activity for ORR than Pt/C in RDE experiments. • Pt/PANI/WC/C showed good stability than that of Pt/C in the presence of methanol. - Abstract: In the present study a Pt/PANI/WC/C electrocatalyst was developed to increase the methanol electro-oxidation and oxygen electro-reduction activity and stability of commercial Pt/C electrocatalyst. WC/C was coated with protonated polyaniline (PANI) in situ during the polymerization of aniline. Fourier transform infrared (FTIR) results illustrate the presence of PANI in the composite. The conductivity of PANI coated – WC/C has been compared with the conductivity of the corresponding mixtures of WC/C and Vulcan XC-72. X-ray diffraction results showed that Pt particles were dispersed on the support with mean particle size of about 10.56 nm. Transition electron microscopy images showed that the nanosized WC/C were successfully coated by PANI. Based on the electrochemical properties characterized by cyclic voltammetry, CO stripping and rotating disk electrode measurements it was found that the as prepared Pt/PANI/WC/C electrocatalyst exhibited a comparable activity for methanol oxidation reaction and oxygen reduction reaction with respect to the commercial one. A significant reduction in the potential of CO electro-oxidation peak from 0.75 V for Pt/C to 0.52 V for Pt/PANI/WC/C electrocatalyst indicates that an increase in the activity for CO electro-oxidation is achieved by replacing the carbon support by PANI coated WC/C. Chronoamerometry results also showed, in the presence of methanol the Pt/PANI/WC/C electrocatalyst still maintains a higher current density than Pt/WC/C and Pt/C.

  7. Sedentary and Physical Activity Habits of Obese Adolescents

    Science.gov (United States)

    Starkoff, Brooke E.; Petosa, Rick L.; Balk, Elizabeth K.; Eneli, Ihuoma U.; Bonny, Andrea E.; Hoffman, Robert P.; Devor, Steven T.

    2014-01-01

    Background: The independent association between sedentary behavior (SB) and physical activity (PA) is such that, regardless of accumulated PA, high amounts of SB are detrimental to health, even in adolescents. Purpose: Our aim was to profile activity patterns in free-living environments and to measure levels of SB and light (LT) and moderate (MOD)…

  8. The relationship between cell phone use, physical and sedentary activity, and cardiorespiratory fitness in a sample of U.S. college students

    Science.gov (United States)

    2013-01-01

    Background Today’s cell phones increase opportunities for activities traditionally defined as sedentary behaviors (e.g., surfing the internet, playing video games). People who participate in large amounts of sedentary behaviors, relative to those who do not, tend to be less physically active, less physically fit, and at greater risk for health problems. However, cell phone use does not have to be a sedentary behavior as these devices are portable. It can occur while standing or during mild-to-moderate intensity physical activity. Thus, the relationship between cell phone use, physical and sedentary activity, and physical fitness is unclear. The purpose of this study was to investigate these relationships among a sample of healthy college students. Methods Participants were first interviewed about their physical activity behavior and cell phone use. Then body composition was assessed and the validated self-efficacy survey for exercise behaviors completed. This was followed by a progressive exercise test on a treadmill to exhaustion. Peak oxygen consumption (VO2 peak) during exercise was used to measure cardiorespiratory fitness. Hierarchical regression was used to assess the relationship between cell phone use and cardiorespiratory fitness after controlling for sex, self-efficacy, and percent body fat. Interview data was transcribed, coded, and Chi-square analysis was used to compare the responses of low and high frequency cell phone users. Results Cell phone use was significantly (p = 0.047) and negatively (β = −0.25) related to cardio respiratory fitness independent of sex, self-efficacy, and percent fat which were also significant predictors (p < 0.05). Interview data offered several possible explanations for this relationship. First, high frequency users were more likely than low frequency users to report forgoing opportunities for physical activity in order to use their cell phones for sedentary behaviors. Second, low frequency users were more

  9. High Temperature Dry Sliding Friction and Wear Performance of Laser Cladding WC/Ni Composite Coating

    Directory of Open Access Journals (Sweden)

    YANG Jiao-xi

    2016-06-01

    Full Text Available Two different types of agglomerate and angular WC/Ni matrix composite coatings were deposited by laser cladding. The high temperature wear resistance of these composite coatings was tested with a ring-on-disc MMG-10 apparatus. The morphologies of the worn surfaces were observed using a scanning electron microscopy (SEM equipped with an energy dispersive spectroscopy (EDS for elemental composition. The results show that the high temperature wear resistance of the laser clad WC/Ni-based composite coatings is improved significantly with WC mass fraction increasing. The 60% agglomerate WC/Ni composite coating has optimal high temperature wear resistance. High temperature wear mechanism of 60% WC/Ni composite coating is from abrasive wear of low temperature into composite function of the oxidation wear and abrasive wear.

  10. Microstructure and property of WC particles ceramic-metal composite coatings by laser surface cladding

    International Nuclear Information System (INIS)

    Zeng Xiaoyan; Zhu Beidi; Tao Zengyi; Yang Shuguo; Cui Kun

    1993-01-01

    Ceramic-metal is widely used as a kind of good hardfacing material. The coarse WC particles ceramic-metal composite coatings with WC density of 67% it weight and the thickness of 1.6-2.0 mm have been cladded on 20Ni 4 Mo steel surface by a 2kw CO 2 laser. The sintered WC particles with the size of 600-1,000 μm are chosen as the main strengthening phase, Ni-base self-flux alloy as the binder in the composite coatings. The microstructure and micro-hardness of both WC particles and binder are analyzed. The rigid ball indention with acoustic emission technique is used to evaluate the brittleness of the coating. Finally, the abrasive wear resistance of the coatings are tested, Besides, the coatings with the same ratio and size of WC particles within low carbon steel tube were cladded on 20Ni 4 Mo steel by atomic hydrogen welding technique and analyzed by the same ways their result are compared

  11. Microstructural examination by TEM of WC/Co composites prepared by conventional and Microwave processes

    International Nuclear Information System (INIS)

    Agrawal, D.; Cheng, J.; Papworth, A.J.; Jain, H.; Williams, D.B.

    2001-01-01

    Recently, significant developments and advances have taken place in the field of microwave processing of ceramics, composites and metals. Microwave sintering technology of WC/Co based hard metal parts has been now developed for commercial products. Microwave processed WC/Co parts reportedly have exhibited superior performance over standard parts. Additionally, the microwave process requires only one tenth of the total cycle time employed in a conventional process. Laboratory corrosion and impact resistance tests have proved that microwave processed WC/Co parts are several times more resistant than the conventional parts of the same composition. The scanning transmission electron microscopic (STEM) examination conducted an conventionally and microwave sintered WC/Co samples exhibited remarkable difference in the chemistry of cobalt binder phase. It is understood that the superior mechanical properties of microwave sintered part are due to the pure cobalt phase present at the grain boundary of WC grains, while the conventionally sintered part showed there was substantial inter-alloying of Co with tungsten. (author)

  12. Physical properties and microstructure of Ti(CN)-based cermets with different WC particle size

    International Nuclear Information System (INIS)

    Deng, Ying; Deng, Ling; Xiong, Xiang; Ye, J.W.; Li, P.P.

    2014-01-01

    Ti(CN)-based cermets with different WC particle sizes from 0.2 to 4 μm were prepared at 1450 °C with 2 MPa Air pressure. The microstructure of cermets was investigated by scanning electron microscope (SEM), X-ray diffraction (XRD), Transmission electron microscope (TEM). The results showed that all the cermets with different WC particle sizes have a typical “core–rim” structure. With the increase of WC powder sizes, the frequency and portion of Ti(C 0.7 N 0.3 ) cores and rim are somewhat decreased while the portion of white core is increased, due to the relative dissolution rate decreasing. In addition, the fracture mode of Ti(C,N) based cermets is a mixture of trans-granular (primary) and inter-granular (subordinate) fracture. The TRS (about 1850 MPa) of the cermets fluctuate slightly with the WC particle sizes from 0.2 to 1.0 μm, but decrease evidently with WC particle sizes up to 2 μm

  13. Sintering, microstructure and properties of WC-AISI304 powder composites

    International Nuclear Information System (INIS)

    Marques, B.J.; Fernandes, C.M.; Senos, A.M.R.

    2013-01-01

    Highlights: ► Total replacement of Co binder by stainless steel AISI 304 in WC based composites. ► Processing conditions for WC–stainless steel composites. ► Mechanical behavior and oxidation resistance of WC–stainless steel composites. -- Abstract: Tungsten carbide–stainless steel (AISI 304) based composites were successfully prepared by powder metallurgy routes using vacuum sintering at a maximum temperature of 1500 °C. The effects of the binder amount (between 6 and 15 wt.%) on the phase composition, microstructure and mechanical properties, namely hardness and fracture toughness, were investigated. Appreciable amount of (M,W) 6 C up to 12 wt.% was detected, especially for the higher SS contents. However, a good compromise between toughness and hardness was observed. Besides that, improved oxidation resistance was noticed in WC–SS based composites compared with WC–Co composites. The results are discussed having in mind the correlation between chemical composition, phase composition, microstructure and mechanical behavior

  14. Neighborhood built environment and socioeconomic status in relation to physical activity, sedentary behavior, and weight status of adolescents.

    Science.gov (United States)

    Sallis, James F; Conway, Terry L; Cain, Kelli L; Carlson, Jordan A; Frank, Lawrence D; Kerr, Jacqueline; Glanz, Karen; Chapman, James E; Saelens, Brian E

    2018-05-01

    The study examined the association of neighborhood walkability to multiple activity-related outcomes and BMI among adolescents and evaluated socioeconomic status as an effect modifier. Cross-sectional study, with adolescents recruited from neighborhoods that met criteria for a 2 × 2 matrix defined by high/low GIS-defined walkability and high/low median income. Adolescents aged 12-16 years (n = 928) were recruited from selected neighborhoods in Maryland and King County, Washington regions in 2009-2011. There were 50.4% girls, and 66.3% were non-Hispanic white, with no medical restrictions on physical activity (PA) or diets. Total PA and sedentary time was assessed by 7 days of accelerometer monitoring. Adolescents self-reported active transport, time spent on 6 sedentary behaviors, and height and weight, used to compute BMI percentiles. Mixed model linear and logistic regressions examined outcomes for association with walkability and income, adjusting for demographic covariates and clustering within block groups. Walkability was positively and significantly related to objectively-measured PA (p < .001) and more frequent walking for transportation (p < .001). Total self-reported sedentary time (p = .048) and TV time (p < .007) were negatively related to walkability. Time in vehicles was negatively related to walkability only among higher-income adolescents. Neighborhood walkability was strongly and consistently associated with adolescents' objectively-assessed total physical activity and reported active transportation. A novel finding was that adolescents living in walkable neighborhoods reported less television time and less time in vehicles. Most results were similar across income categories. Results strengthen the rationale for recommendations to improve walkability. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Patterns of sedentary behavior and compliance with public health recommendations in Spanish adolescents: the AFINOS study Patrones de sedentarismo y cumplimiento de las recomendaciones de salud pública en adolescentes españoles: estudio AFINOS

    Directory of Open Access Journals (Sweden)

    David Martínez Gómez

    2012-12-01

    Full Text Available The aims of the present study were: (i describe patterns of sedentary behavior in Spanish adolescents; and (ii determine the proportion of adolescents that do not meet the public health recommendations for sedentary behavior. This study comprised 1,724 Spanish adolescents (882 girls, aged 13 to 16 years. Patterns of sedentary behavior (TV viewing, use of computer games, console games and surfing the Internet were assessed using the HELENA sedentary behavior questionnaire. The total proportion of adolescents watching TV, using computer and console games, and surfing the internet for more than two hours daily was 24%, 9%, 7%, and 17%, respectively, on weekdays, and 50%, 22%, 16%, and 35%, respectively, on weekends. Over 63% of the adolescents from the study did not meet the recommendation for sedentary behavior (Los objetivos del estudio son: (i describir los patrones de comportamiento sedentario en adolescentes españoles y (ii establecer cuántos de ellos no cumplen las recomendaciones de salud pública sobre comportamiento sedentario. Participaron 1.724 adolescentes españoles (882 chicas entre 13 y 16 años. Los patrones de comportamiento sedentario (ver la televisión, juegos de ordenador, videojuegos y navegar en Internet fueron evaluados a través del cuestionario HELENA. La proporción total de adolescentes que ven la TV, usan juegos de ordenador o de consola y navegan en Internet durante > 2h los días de diario fue del 24%, 9%, 7% y 17%, respectivamente. Durante los fines de semana, la proporción fue del 50%, 22%, 16% y 35%. Más del 63% del total de la muestra no cumplen las recomendaciones de tiempo sedentario total < 2 horas durante los días de diario y el 87% no lo hace en días del fin de semana. Dado que las conductas sedentarias podrían ser relevantes en la salud de los adolescentes, las intervenciones de salud pública son necesarias en España.

  16. Automatic activation of exercise and sedentary stereotypes.

    Science.gov (United States)

    Berry, Tanya; Spence, John C

    2009-09-01

    We examined the automatic activation of "sedentary" and "exerciser" stereotypes using a social prime Stroop task. Results showed significantly slower response times between the exercise words and the exercise control words and between the sedentary words and the exercise control words when preceded by an attractive exerciser prime. Words preceded by a normal-weight exerciser prime showed significantly slower response times for sedentary words over sedentary control words and exercise words. An overweight sedentary prime resulted in significantly slower response times for sedentary words over exercise words and exercise control words. These results highlight the need for increased awareness of how active and sedentary lifestyles are portrayed in the media.

  17. Microstructure and mechanical properties of TiB2–TiC–WC composite ceramic tool materials

    International Nuclear Information System (INIS)

    Song, Jinpeng; Huang, Chuanzhen; Zou, Bin; Liu, Hanlian; Wang, Jun

    2012-01-01

    Highlights: ►Effect of sintering parameters on TiB 2 –TiC–WC composites has been investigated. ► Ni element was dispersed in the interface between WC and matrix grains. ► The fracture mode changed from intergranular fracture to transgranular fracture. ► The microstructure and mechanical properties of the composite were improved. -- Abstract: TiB 2 –TiC–WC composites with Ni as a sintering aid were fabricated by a hot-press technique at 1700 °C and 1650 °C for 1 h, respectively. The microstructure and mechanical properties were investigated. The composites were analyzed by means of scanning electron microscope (SEM), X-ray diffraction (XRD) and energy dispersive spectrometry (EDS). The matrix phases consisted of TiB 2 and TiC. No severe chemical reactions happened between the additive and matrix. The microstructure consisted of the fine WC grains and uniform matrix grains. When the proper WC content added to TiB 2 –TiC composites, the growth of matrix grains was inhibited and the mechanical properties of the composites were improved. The interface energy was strengthened by Ni that dispersed in the interfaces among WC grains and matrix grains, which made the fracture mode change from intergranular fracture to transgranular fracture. The transgranular fracture and the pulling out of WC grains played a predominant role in the propagating of cracks when WC content was 20 wt.% in TiB 2 –TiC–WC composites. The optimal mechanical properties of TiB 2 –TiC–20 wt.%WC composite were 955.71 MPa of flexural strength, 7.5 MPa m 1/2 of fracture toughness and 23.5 GPa of Vickers hardness.

  18. Classification Accuracy of a Wearable Activity Tracker for Assessing Sedentary Behavior and Physical Activity in 3–5-Year-Old Children

    Directory of Open Access Journals (Sweden)

    Wonwoo Byun

    2018-03-01

    Full Text Available This study examined the accuracy of the Fitbit activity tracker (FF for quantifying sedentary behavior (SB and varying intensities of physical activity (PA in 3–5-year-old children. Twenty-eight healthy preschool-aged children (Girls: 46%, Mean age: 4.8 ± 1.0 years wore the FF and were directly observed while performing a set of various unstructured and structured free-living activities from sedentary to vigorous intensity. The classification accuracy of the FF for measuring SB, light PA (LPA, moderate-to-vigorous PA (MVPA, and total PA (TPA was examined calculating Pearson correlation coefficients (r, mean absolute percent error (MAPE, Cohen’s kappa (k, sensitivity (Se, specificity (Sp, and area under the receiver operating curve (ROC-AUC. The classification accuracies of the FF (ROC-AUC were 0.92, 0.63, 0.77 and 0.92 for SB, LPA, MVPA and TPA, respectively. Similarly, values of kappa, Se, Sp and percentage of correct classification were consistently high for SB and TPA, but low for LPA and MVPA. The FF demonstrated excellent classification accuracy for assessing SB and TPA, but lower accuracy for classifying LPA and MVPA. Our findings suggest that the FF should be considered as a valid instrument for assessing time spent sedentary and overall physical activity in preschool-aged children.

  19. [Gender-specific manifestations of daily physical activity and sedentary behaviour in elderly people of Surgut].

    Science.gov (United States)

    Loginov, S I; Malkov, M N; Nikolayev, A Yu

    2017-01-01

    Objective of the study was to establish gender-specific characteristics of physical activity (PA) and sedentary behavior in elderly people living in Yugra North. 295 residents of Surgut (102 men aged 62,9±5,3 years, 35%; 193 women aged 61,9±3,8 years, 65%) were subject to a IPAQ-RU questionnaire. The study revealed the gender-specific differences in body length and mass, body mass and body fat indices. It was detected that more energy is spent on the housework and physical activity in the country (moderate-intensity physical activity for women and high-intensity one for men). The study data showed no statistically significant gender-specific differences in general physical activity. Sedentary behavior is more popular among men rather than women (2543 vs 2441 min/week). 47% of low-active men and 56% of women reported the sitting times of 6-9 hours per day, 42% - 9-12 hours per day. Actions need to be taken to increase physical activity which is low at the moment and decrease sedentary behavior which is currently on the high level.

  20. Are screen-based sedentary behaviors longitudinally associated with dietary behaviors and leisure-time physical activity in the transition into adolescence?

    Science.gov (United States)

    Gebremariam, Mekdes K; Bergh, Ingunn H; Andersen, Lene F; Ommundsen, Yngvar; Totland, Torunn H; Bjelland, Mona; Grydeland, May; Lien, Nanna

    2013-01-25

    There is a need for more longitudinal studies investigating the associations between screen-based sedentary behaviors (SB), dietary behaviors and leisure-time physical activity (PA). In the HEIA cohort study, 908 children were followed from age 11 to age 13 (September 2007-May 2009). The children self-reported their intake of fruits, vegetables, soft drinks with sugar and snacks. TV/DVD use, computer/game use and leisure-time PA were also self-reported. Multilevel generalized linear mixed model analysis was used to assess longitudinal associations between the screen-based SB and each of the two other behaviors. Twenty-month changes in TV/DVD use and computer/game use were positively associated with changes in the consumption of soft drinks with sugar and unhealthy snacks in the same period; and inversely associated with change in vegetable consumption. Change in computer/game use was also inversely related to change in fruit consumption. An inverse but non-substantive association was found between change in TV/DVD use and change in leisure-time PA. Change in computer/game use was not significantly associated with change in leisure-time PA. Changes in screen-based SB were associated with multiple unfavorable changes in dietary habits, although the associations were weak. These associations need to be further investigated in intervention/experimental studies, to assess whether changing screen-based SB will result in clinically relevant changes in dietary behaviors. However, the findings of this study suggest that screen-based SB and leisure-time PA are largely independent behaviors which should be addressed separately in health promotion activities.

  1. Association of Socioeconomic Factors and Sedentary Lifestyle in Belgrade's Suburb, Working Class Community.

    Science.gov (United States)

    Konevic, Slavica; Martinovic, Jelena; Djonovic, Nela

    2015-08-01

    Sedentary lifestyle represents a growing health problem and considering that there is already a range of unhealthy habits that are marked as health risk factors and the increasing prevalence of sedentary lifestyle worldwide, we aimed to investigate association of sedentary way of living in suburb, working class local community with socioeconomic determinants such as educational level, occupation and income status. In this community-based cross-sectional study, 1126 independently functioning adults were enrolled into the study. The study protocol included a complete clinical and biochemical investigation revealing age, gender, lipid status, height, weight and blood pressure. Trained interviewers (nurses) collected information from patients about current state of chronic diseases (diabetes mellitus, arterial hypertension) smoking, medication and other socioeconomic data. Descriptive analysis, Chi-square and logistic regression were performed as statistical calculations. Patients with elementary school were seven times more likely to be classified in category with sedentary lifestyle compared to patients with college or faculty degree. Being retired and reporting low income were significantly associated with higher odds of sedentary behavior when compared with students and patients with high-income status, respectively. The significance of this study lies in the fact that our results may help to easier identification of patients who may have a tendency towards a sedentary lifestyle.

  2. Can sedentary behavior be made more active? A randomized pilot study of TV commercial stepping versus walking.

    Science.gov (United States)

    Steeves, Jeremy A; Bassett, David R; Fitzhugh, Eugene C; Raynor, Hollie A; Thompson, Dixie L

    2012-08-06

    There is a growing problem of physical inactivity in America, and approximately a quarter of the population report being completely sedentary during their leisure time. In the U.S., TV viewing is the most common leisure-time activity. Stepping in place during TV commercials (TV Commercial Stepping) could increase physical activity. The purpose of this study was to examine the feasibility of incorporating physical activity (PA) into a traditionally sedentary activity, by comparing TV Commercial Stepping during 90 min/d of TV programming to traditional exercise (Walking). A randomized controlled pilot study of the impact of 6 months of TV Commercial Stepping versus Walking 30 min/day in adults was conducted. 58 sedentary, overweight (body mass index 33.5 ± 4.8 kg/m2) adults (age 52.0 ± 8.6 y) were randomly assigned to one of two 6-mo behavioral PA programs: 1) TV Commercial Stepping; or 2) Walking 30 min/day. To help facilitate behavior changes participants received 6 monthly phone calls, attended monthly meetings for the first 3 months, and received monthly newsletters for the last 3 months. Using intent-to-treat analysis, changes in daily steps, TV viewing, diet, body weight, waist and hip circumference, and percent fat were compared at baseline, 3, and 6 mo. Data were collected in 2010-2011, and analyzed in 2011. Of the 58 subjects, 47 (81%) were retained for follow-up at the completion of the 6-mo program. From baseline to 6-mo, both groups significantly increased their daily steps [4611 ± 1553 steps/d vs. 7605 ± 2471 steps/d (TV Commercial Stepping); 4909 ± 1335 steps/d vs. 7865 ± 1939 steps/d (Walking); P TV viewing and dietary intake decreased significantly in both groups. Body weight did not change, but both groups had significant decreases in percent body fat (3-mo to 6-mo), and waist and hip circumference (baseline to 6-mo) over time. Participants in both the TV Commercial Stepping and Walking groups had favorable changes in

  3. PREPARATION OF WC-Co POWDER BY DIRECT REDUCTION AND CARBONIZATION

    Institute of Scientific and Technical Information of China (English)

    Zhonglai Yi; Gangqin Shao; Xinglong Duan; Peng Sun; Xiaoliang Shi; Zhen Xiong; Jingkun Guo

    2005-01-01

    A new approach to produce superfine WC-Co powder by direct reduction and carbonization is proposed.Water-soluble salts containing W and Co were used as raw materials. Tungsten and cobalt oxide powder (CoWO4/WO3)was first formed by a spray-pyrolysis technique, which was then mixed with carbon black and converted to WC-Co composite powder at 950℃ for 4 h in N2 atmosphere. The resulting powder has a particle size of 100-300 nm.

  4. Sedentary Lifestyle and High-Carbohydrate Intake are Associated with Low-Grade Chronic Inflammation in Post-Menopause: A Cross-sectional Study.

    Science.gov (United States)

    Alves, Bruna Cherubini; Silva, Thaís Rasia da; Spritzer, Poli Mara

    2016-07-01

    Introduction Cardiovascular disease (CVD) is the leading cause of death in post menopausal women, and inflammation is involved in the atherosclerosis process. Purpose to assess whether dietary pattern, metabolic profile, body composition and physical activity are associated with low-grade chronic inflammation according to high-sensitivity C-reactive protein (hs-CRP) levels in postmenopausal women. Methods ninety-five postmenopausal participants, with no evidence of clinical disease, underwent anthropometric, metabolic and hormonal assessments. Usual dietary intake was assessed with a validated food frequency questionnaire, habitual physical activity was measured with a digital pedometer, and body composition was estimated by bioelectrical impedance analysis. Patients with hs-CRP ≥10 mg/L or using hormone therapy in the last three months before the study were excluded from the analysis. Participants were stratified according to hs-CRP lower or ≥3 mg/L. Sedentary lifestyle was defined as walking fewer than 6 thousand steps a day. Two-tailed Student's t-test, Wilcoxon-Mann-Whitney U or Chi-square (χ(2)) test were used to compare differences between groups. A logistic regression model was used to estimate the odds ratio of variables for high hs-CRP. Results participants with hs-CRP ≥3 mg/L had higher body mass index (BMI), body fat percentage, waist circumference (WC), triglycerides, glucose, and homeostasis model assessment of insulin resistance (HOMA-IR) (p = 0.01 for all variables) than women with hs-CRP sedentary lifestyle (p sedentary lifestyle (4.7, 95% confidence interval [95%CI] 1.4-15.5) and carbohydrate intake (2.9, 95%CI 1.1-7.7). Conclusions sedentary lifestyle and high-carbohydrate intake were associated with low-grade chronic inflammation and cardiovascular risk in postmenopause. Thieme Publicações Ltda Rio de Janeiro, Brazil.

  5. Leisure-Time Physical Activity and Sedentary Behavior and Their Cross-Sectional Associations with Excessive Daytime Sleepiness in the French SU.VI.MAX-2 Study.

    Science.gov (United States)

    Andrianasolo, Roland M; Menai, Mehdi; Galan, Pilar; Hercberg, Serge; Oppert, Jean-Michel; Kesse-Guyot, Emmanuelle; Andreeva, Valentina A

    2016-04-01

    The potential benefit of physical activity in terms of decreasing excessive daytime sleepiness (EDS) prevalence is unclear, especially in aging adults. We aimed to elucidate the associations among physical activity, sedentariness, and EDS in middle-aged and older adults. We conducted a cross-sectional analysis using data from a subsample of participants in the SU.VI.MAX-2 observational study (2007-2009; N = 4179; mean age = 61.9 years). EDS was defined as a score >10 on the Epworth Sleepiness Scale. Leisure-time physical activity and different types of sedentary behavior were assessed with the Modifiable Activity Questionnaire. The associations were examined with multivariable logistic regression models. In the adjusted multivariable model, total leisure-time physical activity (modeled in quartiles, Q) was significantly, inversely associated with EDS (odds ratios (OR)Q4 vs Q1 = 0.70, 95 % confidence interval (CI) = 0.54-0.89). The association persisted in analyses restricted to individuals not taking sleep medication (ORQ4 vs Q1 = 0.72, 95 % CI = 0.54-0.95). In turn, time spent watching television and time spent reading appeared protective against EDS (ORQ4 vs Q1 = 0.73, 95 % CI = 0.57-0.94; ORQ4 vs Q1 = 0.76, 95 % CI = 0.60-0.97, respectively), whereas time spent on a computer appeared to confer an increased risk for EDS (ORQ4 vs Q1 = 1.30, 95 % CI = 1.05-1.62). When physical activity and sedentariness were modeled jointly, using WHO recommendation-based cutoffs for high/low levels, no significant associations were observed in the fully adjusted models. The findings reinforce public health recommendations promoting behavior modification and specifically moderate-intensity exercise in middle-aged and older adults. The association of high physical activity/low sedentariness with EDS, which was not supported by the data, merits further investigation before firm conclusions could be drawn.

  6. Associations between physical activity, sedentary behavior, and glycemic control in a large cohort of adolescents with type 1 diabetes : the Hvidoere Study Group on Childhood Diabetes

    NARCIS (Netherlands)

    Aman, J.; Skinner, T. C.; de Beaufort, C. E.; Swift, P. G. F.; Aanstoot, H-J; Cameron, F.

    angstrom man J, Skinner TC, de Beaufort CE, Swift PGF, Aanstoot H-J, Cameron F, for and on behalf of the Hvidoere Study Group on Childhood Diabetes. Associations between physical activity, sedentary behavior, and glycemic control in a large cohort of adolescents with type 1 diabetes: the Hvidoere

  7. [Sport habits and sedentary lifestyle among elementary school children in Obuda, Hungary].

    Science.gov (United States)

    Kovács, Viktória Anna; Gábor, Anita; Fajcsák, Zsuzsanna; Martos, Eva

    2010-04-18

    Childhood obesity has become a worldwide epidemic. Declining physical activity is one of the major contributors. To obtain data on Hungarian primary school students' weight status, sport club participation and sedentary behaviors. A cross-sectional survey was distributed to all primary schools (n=18) in Obuda, Budapest. Children (1648 boys, 1654 girls; 11.3+/-2.3 years) completed questionnaires about sedentary behaviors and sport participation. Height, weight and waist circumference were measured. According to the IOTF criteria, 14.5% of the children were overweight and 4.6% were obese. The rate of those children who did not attend any extracurricular sport increased parallel with age in both gender. At the lower end of the range, 15.3% of the 9-year-old boys and 21% of the 10-year old girls did not sport. These numbers increased up to 31.0% in boys and 53.8% in girls by the age of 15 years. Screening time on weekdays and on weekends was 2.2+/-1.9 and 3.6+/-2.6 hours/day, respectively. One third of participants (32.2%) spent >2 h/day in front of a screen on weekdays, whereas 61.8% did on weekends. The frequency of sedentary behaviors was high among urban Hungarian school children. Health promotion strategies should start in early ages.

  8. Associations between physical activity, sedentary time, sleep duration and daytime sleepiness in US adults.

    Science.gov (United States)

    McClain, James J; Lewin, Daniel S; Laposky, Aaron D; Kahle, Lisa; Berrigan, David

    2014-09-01

    To examine the associations between objectively measured physical activity (PA) or sedentary behavior and self-reported sleep duration or daytime sleepiness in a nationally representative sample of healthy US adults (N=2128). We report analyses of four aspects of sedentary behavior and PA derived from accelerometry data (minutes of sedentary time, activity counts/minute, Minutes of Moderate and Vigorous PA [MVPA], and MVPA in 10-minute bouts) versus self-report of sleep duration and frequency of daytime sleepiness from the 2005-2006 National Health and Nutrition Examination Survey. Age and sex dependence of associations between PA and sleep were observed. Aspects of PA were significantly lower in adults reporting more frequent daytime sleepiness in younger (20-39) and older (≥ 60) age groups, but not in middle-aged (40-59), respondents. In younger respondents, PA increased with sleep duration, but in middle aged and older respondents PA was either unrelated to sleep duration or lower in those reporting ≥ 8 h of sleep. Objectively measured sedentary time showed limited evidence of associations with sleep duration. Further research delineating the relationships between sleep and PA is important because both activities have been implicated in diverse health outcomes as well as in the etiology of obesity. Published by Elsevier Inc.

  9. Surface analysis of WC--Co composite materials (2) Quantitative Auger electron spectrometry

    International Nuclear Information System (INIS)

    Tongson, L.L.; Biggers, J.V.; Dayton, G.O.; Bind, J.M.; Knox, B.E.

    1978-01-01

    The unique sensitivity of Auger electron spectrometry (AES) to combined carbon has been exploited in measuring the surface compositions of hot-pressed, conventionally sintered and mixed powders of WC--Co composite materials. AES sensitivity factors for tungsten and carbon (in WC) relative to cobalt were determined. The concentrations of the major elements in hot-pressed samples measured with AES using the relative sensitivity method were compared to those obtained independently by electron microprobe (EMP) and x-ray fluorescence (XRF) techniques. Corollary studies using ion scattering spectrometry (ISS) showed the absence of (1) matrix effects in the AES measurements, (2) preferential sputtering during ion bombardment, and (3) deposition of the easier-to-sputter component (cobalt) onto WC

  10. Exploring the potential role of tungsten carbide cobalt (WC-Co) nanoparticle internalization in observed toxicity toward lung epithelial cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Armstead, Andrea L. [Biomaterials, Bioengineering and Nanotechnology Laboratory, Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV 26506 (United States); Pharmaceutical and Pharmacological Sciences Graduate Program, School of Pharmacy, West Virginia University, Morgantown, WV 26506 (United States); Arena, Christopher B. [Biomaterials, Bioengineering and Nanotechnology Laboratory, Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV 26506 (United States); E.J. Van Liere Research Program, School of Medicine, West Virginia University, Morgantown, WV 26506 (United States); Li, Bingyun, E-mail: bili@hsc.wvu.edu [Biomaterials, Bioengineering and Nanotechnology Laboratory, Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV 26506 (United States); Pharmaceutical and Pharmacological Sciences Graduate Program, School of Pharmacy, West Virginia University, Morgantown, WV 26506 (United States); E.J. Van Liere Research Program, School of Medicine, West Virginia University, Morgantown, WV 26506 (United States); Mary Babb Randolph Cancer Center, Morgantown, WV 26506 (United States)

    2014-07-01

    Tungsten carbide cobalt (WC-Co) has been recognized as a workplace inhalation hazard in the manufacturing, mining and drilling industries by the National Institute of Occupational Safety and Health. Exposure to WC-Co is known to cause “hard metal lung disease” but the relationship between exposure, toxicity and development of disease remain poorly understood. To better understand this relationship, the present study examined the role of WC-Co particle size and internalization on toxicity using lung epithelial cells. We demonstrated that nano- and micro-WC-Co particles exerted toxicity in a dose- and time-dependent manner and that nano-WC-Co particles caused significantly greater toxicity at lower concentrations and shorter exposure times compared to micro-WC-Co particles. WC-Co particles in the nano-size range (not micron-sized) were internalized by lung epithelial cells, which suggested that internalization may play a key role in the enhanced toxicity of nano-WC-Co particles over micro-WC-Co particles. Further exploration of the internalization process indicated that there may be multiple mechanisms involved in WC-Co internalization such as actin and microtubule based cytoskeletal rearrangements. These findings support our hypothesis that WC-Co particle internalization contributes to cellular toxicity and suggest that therapeutic treatments inhibiting particle internalization may serve as prophylactic approaches for those at risk of WC-Co particle exposure. - Highlights: • Hard metal (WC-Co) particle toxicity was established in lung epithelial cells. • Nano-WC-Co particles caused greater toxicity than micro-WC-Co particles. • Nano- and micro-WC-Co particles were capable of inducing cellular apoptosis. • Nano-WC-Co particles were internalized by lung epithelial cells. • WC-Co particle internalization was mediated by actin dynamics.

  11. Exploring the potential role of tungsten carbide cobalt (WC-Co) nanoparticle internalization in observed toxicity toward lung epithelial cells in vitro

    International Nuclear Information System (INIS)

    Armstead, Andrea L.; Arena, Christopher B.; Li, Bingyun

    2014-01-01

    Tungsten carbide cobalt (WC-Co) has been recognized as a workplace inhalation hazard in the manufacturing, mining and drilling industries by the National Institute of Occupational Safety and Health. Exposure to WC-Co is known to cause “hard metal lung disease” but the relationship between exposure, toxicity and development of disease remain poorly understood. To better understand this relationship, the present study examined the role of WC-Co particle size and internalization on toxicity using lung epithelial cells. We demonstrated that nano- and micro-WC-Co particles exerted toxicity in a dose- and time-dependent manner and that nano-WC-Co particles caused significantly greater toxicity at lower concentrations and shorter exposure times compared to micro-WC-Co particles. WC-Co particles in the nano-size range (not micron-sized) were internalized by lung epithelial cells, which suggested that internalization may play a key role in the enhanced toxicity of nano-WC-Co particles over micro-WC-Co particles. Further exploration of the internalization process indicated that there may be multiple mechanisms involved in WC-Co internalization such as actin and microtubule based cytoskeletal rearrangements. These findings support our hypothesis that WC-Co particle internalization contributes to cellular toxicity and suggest that therapeutic treatments inhibiting particle internalization may serve as prophylactic approaches for those at risk of WC-Co particle exposure. - Highlights: • Hard metal (WC-Co) particle toxicity was established in lung epithelial cells. • Nano-WC-Co particles caused greater toxicity than micro-WC-Co particles. • Nano- and micro-WC-Co particles were capable of inducing cellular apoptosis. • Nano-WC-Co particles were internalized by lung epithelial cells. • WC-Co particle internalization was mediated by actin dynamics

  12. Benzotriazole (BTA), A Promising Corrosion Inhibitor for WC-Co Hardmetal

    Energy Technology Data Exchange (ETDEWEB)

    Schnyder, B.; Stoessel-Sittig, C.; Koetz, R.; Hochstrasser-Kurz, S. [ETH Zuerich (Switzerland); Virtanen, S. [ETH Zuerich (Switzerland); Jaeggi, Ch. [University of Bern (Switzerland); Eichenberger, N. [University of Bern (Switzerland); Szoecs, E. [University of Bern (Switzerland); Siegenthaler, H. [University of Bern (Switzerland); Ziegler, P. [AGIE SA (Switzerland); Beltrami, I. [AGIE SA (Switzerland)

    2004-03-01

    Wire Electro-Discharge Machining (W-EDM) of tungsten carbide with Co-binder may lead to corrosion and discolouration at the surface. The corrosion behaviour of WC-Co based hardmetal was investigated in different aqueous solutions (acidic, neutral, and alkaline solutions). At open-circuit potential WC-Co based hardmetals show rather high dissolution rates in all types of electrolyte. An efficient corrosion inhibitor (benzotriazole, C{sub 6}H{sub 5}N{sub 3}) could be found for a borate buffer solution, pH = 8.4. (author)

  13. Leisure sedentary time is differentially associated with hypertension, diabetes mellitus, and hyperlipidemia depending on occupation

    Directory of Open Access Journals (Sweden)

    Man Sup Lim

    2017-03-01

    Full Text Available Abstract Background Sedentary behavior is considered an independent cause of cardio-metabolic diseases, regardless of physical activity level and obesity. Few studies have reported the association between leisure sedentary time and cardio-vascular diseases in terms of occupation. Methods We performed a cross-sectional study using data from the Korean Community Health Survey (KCHS for 240,086 participants assessed in 2011 and 2013. Occupation was categorized into four groups: farmer or fisherman, laborer, and soldier (Group I; service worker, salesperson, technician, mechanic, production worker, and engineer (Group II; manager, expert, specialist, and clerk (Group III; and unemployed (Group IV. Leisure sedentary time was divided into five groups: 0 h, 1 h, 2 h, 3 h, and 4+ h. The association between leisure sedentary time on weekdays and hypertension/diabetes mellitus/hyperlipidemia for different occupations was analyzed using simple and multiple logistic regression analyses with complex sampling. Results In Groups I, II and III, no length of sedentary time was associated with hypertension, and only 3 h or 4+ h of sedentary time was associated with diabetes mellitus and hyperlipidemia. Group IV showed a significant association with hypertension and diabetes mellitus for the 2 h, 3 h, and 4+ h sedentary times. Conclusions The unemployed are more susceptible than other occupation groups to cardio-metabolic diseases when leisure time is sedentary.

  14. Leisure sedentary time is differentially associated with hypertension, diabetes mellitus, and hyperlipidemia depending on occupation.

    Science.gov (United States)

    Lim, Man Sup; Park, Bumjung; Kong, Il Gyu; Sim, Songyong; Kim, So Young; Kim, Jin-Hwan; Choi, Hyo Geun

    2017-03-23

    Sedentary behavior is considered an independent cause of cardio-metabolic diseases, regardless of physical activity level and obesity. Few studies have reported the association between leisure sedentary time and cardio-vascular diseases in terms of occupation. We performed a cross-sectional study using data from the Korean Community Health Survey (KCHS) for 240,086 participants assessed in 2011 and 2013. Occupation was categorized into four groups: farmer or fisherman, laborer, and soldier (Group I); service worker, salesperson, technician, mechanic, production worker, and engineer (Group II); manager, expert, specialist, and clerk (Group III); and unemployed (Group IV). Leisure sedentary time was divided into five groups: 0 h, 1 h, 2 h, 3 h, and 4+ h. The association between leisure sedentary time on weekdays and hypertension/diabetes mellitus/hyperlipidemia for different occupations was analyzed using simple and multiple logistic regression analyses with complex sampling. In Groups I, II and III, no length of sedentary time was associated with hypertension, and only 3 h or 4+ h of sedentary time was associated with diabetes mellitus and hyperlipidemia. Group IV showed a significant association with hypertension and diabetes mellitus for the 2 h, 3 h, and 4+ h sedentary times. The unemployed are more susceptible than other occupation groups to cardio-metabolic diseases when leisure time is sedentary.

  15. Let Me Relax: Toward Automated Sedentary State Recognition and Ubiquitous Mental Wellness Solutions

    Directory of Open Access Journals (Sweden)

    Vijay Rajanna

    2018-12-01

    Full Text Available Advances in ubiquitous computing technology improve workplace productivity, reduce physical exertion, but ultimately result in a sedentary work style. Sedentary behavior is associated with an increased risk of stress, obesity, and other health complications. Let Me Relax is a fully automated sedentary-state recognition framework using a smartwatch and smartphone, which encourages mental wellness through interventions in the form of simple relaxation techniques. The system was evaluated through a comparative user study of 22 participants split into a test and a control group. An analysis of NASA Task Load Index pre- and post- study survey revealed that test subjects who followed relaxation methods, showed a trend of both increased activity as well as reduced mental stress. Reduced mental stress was found even in those test subjects that had increased inactivity. These results suggest that repeated interventions, driven by an intelligent activity recognition system, is an effective strategy for promoting healthy habits, which reduce stress, anxiety, and other health risks associated with sedentary workplaces.

  16. The conceptualization of a Just-In-Time Adaptive Intervention (JITAI) for the reduction of sedentary behavior in older adults.

    Science.gov (United States)

    Müller, Andre Matthias; Blandford, Ann; Yardley, Lucy

    2017-01-01

    Low physical activity and high sedentary behavior in older adults can be addressed with interventions that are delivered through modern technology. Just-In-Time Adaptive Interventions (JITAIs) are an emerging technology-driven behavior-change intervention type and capitalize on data that is collected via mobile sensing technology (e.g., smartphones) to trigger appropriate support in real-life. In this paper we integrated behavior change and aging theory and research as well as knowledge around older adult's technology use to conceptualize a JITAI targeting the reduction of sedentary behavior in older adults. The JITAIs ultimate goal is to encourage older adults to take regular activity breaks from prolonged sitting. As a proximal outcome, we suggest the number of daily activity breaks from sitting. Support provided to interrupt sitting time can be based on tailoring variables: (I) the current accumulated sitting time; (II) the location of the individual; (III) the time of the day; (IV) the frequency of daily support prompts; and (V) the response to previous support prompts. Data on these variables can be collected using sensors that are commonly inbuilt into smartphones (e.g., accelerometer, GPS). Support prompts might be best delivered via traditional text messages as older adults are usually familiar and comfortable with this function. The content of the prompts should encourage breaks from prolonged sitting by highlighting immediate benefits of sitting time interruptions. Additionally, light physical activities that could be done during the breaks should also be presented (e.g., walking into the kitchen to prepare a cup of tea). Although the conceptualized JITAI can be developed and implemented to test its efficacy, more work is required to identify ways to collect, aggregate, organize and immediately use dense data on the proposed and other potentially important tailoring variables. Machine learning and other computational modelling techniques commonly used by

  17. Production and Characterization of WC-Reinforced Co-Based Superalloy Matrix Composites

    Science.gov (United States)

    Özgün, Özgür; Dinler, İlyas

    2018-05-01

    Cobalt-based superalloy matrix composite materials were produced through the powder metallurgy technique using element powders at high purity and nano-sized wolfram carbide (WC) reinforcement in this study. An alloy that had the same chemical composition as the Stellite 6 alloy but not containing carbon was selected as the matrix alloy. The powder mixtures obtained as a result of mixing WC reinforcing member and element powders at the determined ratio were shaped by applying 300 MPa of pressure. The green components were sintered under argon atmosphere at 1240 °C for 120 minutes. The densities of the sintered components were determined by the Archimedes' principle. Microstructural characterization was performed via X-ray diffraction analysis, scanning electron microscope examinations, and energy-dispersive spectrometry. Hardness measurements and tensile tests were performed for determining mechanical characteristics. The relative density values of the sintered components increased by increasing the WC reinforcement ratio and they could almost reach the theoretical density. It was determined from the microstructural examinations that the composite materials consisted of fine and equiaxed grains and coarse carbides demonstrating a homogeneous dispersion along the microstructure at the grain boundaries. As it was the case in the density values, the hardness and strength values of the composites increased by increasing the WC ratio.

  18. Fracture toughness measurements of WC-based hard metals

    International Nuclear Information System (INIS)

    Prakash, L.; Albert, B.

    1983-01-01

    The fracture toughness of WC-based cemented carbides was determined by different methods. The values obtained are dependent on the procedure of measurement. Each method thoughness of hard metals mutually. (orig.) [de

  19. Soft phonon modes driven huge difference on lattice thermal conductivity between topological semimetal WC and WN

    Science.gov (United States)

    Guo, San-Dong; Chen, Peng

    2018-04-01

    Topological semimetals are currently attracting increasing interest due to their potential applications in topological qubits and low-power electronics, which are closely related to their thermal transport properties. Recently, the triply degenerate nodal points near the Fermi level of WC are observed by using angle-resolved photoemission spectroscopy. In this work, by solving the Boltzmann transport equation based on first-principles calculations, we systematically investigate the phonon transport properties of topological semimetals WC and WN. The predicted room-temperature lattice thermal conductivities of WC (WN) along the a and c directions are 1140.64 (7.47) W m-1 K-1 and 1214.69 (5.39) W m-1 K-1. Considering the similar crystal structure of WC and WN, it is quite interesting to find that the thermal conductivity of WC is more than two orders of magnitude higher than that of WN. It is found that, different from WN, the large acoustic-optical (a-o) gap prohibits the acoustic+acoustic → optical (aao) scattering, which gives rise to very long phonon lifetimes, leading to ultrahigh lattice thermal conductivity in WC. For WN, the lack of an a-o gap is due to soft phonon modes in optical branches, which can provide more scattering channels for aao scattering, producing very short phonon lifetimes. Further deep insight can be attained from their different electronic structures. Distinctly different from that in WC, the density of states of WN at the Fermi level becomes very sharp, which leads to destabilization of WN, producing soft phonon modes. It is found that the small shear modulus G and C44 limit the stability of WN, compared with WC. Our studies provide valuable information for phonon transports in WC and WN, and motivate further experimental studies to study their lattice thermal conductivities.

  20. Sedentary behaviour profiling of office workers: a sensitivity analysis of sedentary cut-points

    NARCIS (Netherlands)

    Boerema, Simone Theresa; Essink, Gerard B.; Tönis, Thijs; van Velsen, Lex Stefan; Hermens, Hermanus J.

    2016-01-01

    Measuring sedentary behaviour and physical activity with wearable sensors provides detailed information on activity patterns and can serve health interventions. At the basis of activity analysis stands the ability to distinguish sedentary from active time. As there is no consensus regarding the

  1. Time spent in sedentary activities in a pediatric population in Pretoria Central, South Africa.

    Science.gov (United States)

    Goon, Daniel T; Nsibambi, Constance A; Chebet, Milton

    2016-12-01

    Scant information exist on screen time behavior of South Africa children and whether they do not meet the recommendation of American Association of Pediatrics (AAP) concerning screen time activity for children is only speculative. Therefore, the purpose of this study was to examine the time spent in sedentary activities, especially screen time of South African children with regard to gender. This cross-sectional study involved a random sample of 1136 school children (548 boys; 588 girls) aged 9-13 years attending public schools in Central Pretoria, South Africa. Questionnaire was used to collect data on the participants' sedentary behaviors. The prevalence estimates for sedentary time activity was based on the guidelines (i.e., <2 or ≥2 hours per day) of AAP. The mean age of the children was 11.1±1.4 years. Sedentary activity data were collected from 548 boys (48.2%) and 588 (51.8%) girls. The majority of children spent more than two hours per day (exceeding the AAP recommendation for sedentary activity) watching TV (3.0%), worked or played on the computer (25.4%), read (1.0%), played music (27.9%), played board games (14.7%), washing clothes (8.0%), floor sweeping (10.5%), art work (18.2%), and spent time on other unspecified activities (28.6%). Boys spent more time (2 hours, 3-4 hours) watching TV (38.3%; P=0.001), playing computer (31.8 %; P=0.024) and board games (17.4%; P=0.012) than girls. The corresponding figures for girls were 35.7%, 19.2% and 12.5% for TV, computer and board games, respectively. However, the proportion of those who spent more time playing music was higher among girls (32.7%) than boys (22.4%) (P=0.002). Overall, the time spent exceeding AAP recommendation (≥ 2 hours) was not statistically (P=0.427) different between boys and girls. The time spent in sedentary activities, particularly in screen time activity among urban primary school children in Pretoria Central is excessively higher than the recommendation (i.e., ≥2 hours per day

  2. The influence of aggregates type on W/C ratio on the strength and other properties of concrete

    Science.gov (United States)

    Malaiskiene, J.; Skripkiunas, G.; Vaiciene, M.; Karpova, E.

    2017-10-01

    The influence of different types of aggregates and W/C ratio on concrete properties is analysed. In order to achieve this aim, lightweight (with expanded clay aggregate) and normal concrete (with gravel aggregate) mixtures are prepared with different W/C ratios. Different W/C ratios are selected by reducing the amount of cement when the amount of water is constant. The following properties of concrete have been determined: density, compressive strength and water absorption. Additionally, the statistical data analysis is performed and influence of aggregate type and W/C ratio on concrete properties is determined. The empirical equations indicating dependence between concrete strength and W/C and strength of aggregate are obtained for normal concrete and light-weight concrete.

  3. Nanotoxicity: emerging concerns regarding nanomaterial safety and occupational hard metal (WC-Co) nanoparticle exposure.

    Science.gov (United States)

    Armstead, Andrea L; Li, Bingyun

    As the number of commercial and consumer products containing engineered nanomaterials (ENMs) continually rises, the increased use and production of these ENMs presents an important toxicological concern. Although ENMs offer a number of advantages over traditional materials, their extremely small size and associated characteristics may also greatly enhance their toxic potentials. ENM exposure can occur in various consumer and industrial settings through inhalation, ingestion, or dermal routes. Although the importance of accurate ENM characterization, effective dosage metrics, and selection of appropriate cell or animal-based models are universally agreed upon as important factors in ENM research, at present, there is no "standardized" approach used to assess ENM toxicity in the research community. Of particular interest is occupational exposure to tungsten carbide cobalt (WC-Co) "dusts," composed of nano- and micro-sized particles, in hard metal manufacturing facilities and mining and drilling industries. Inhalation of WC-Co dust is known to cause "hard metal lung disease" and an increased risk of lung cancer; however, the mechanisms underlying WC-Co toxicity, the inflammatory disease state and progression to cancer are poorly understood. Herein, a discussion of ENM toxicity is followed by a review of the known literature regarding the effects of WC-Co particle exposure. The risk of WC-Co exposure in occupational settings and the updates of in vitro and in vivo studies of both micro- and nano-WC-Co particles are discussed.

  4. A theoretical understanding on the CO-tolerance mechanism of the WC(0001) supported Pt monolayer: Some improvement strategies

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xilin [College of Physics and Materials Science, Henan Normal University, Xinxiang, 453007 (China); Lu, Zhansheng [College of Physics and Materials Science, Henan Normal University, Xinxiang, 453007 (China); Collaborative Innovation Center of Nano Functional Materials and Applications, Henan Province (China); Yang, Zongxian, E-mail: yzx@henannu.edu.cn [College of Physics and Materials Science, Henan Normal University, Xinxiang, 453007 (China); Collaborative Innovation Center of Nano Functional Materials and Applications, Henan Province (China)

    2016-12-15

    Highlights: • The mechanism of CO tolerance and oxidation on Pt{sub ML}/WC(0001) is clarified. • The high tolerance of Pt{sub ML}/WC(0001) to CO originate from the weak adsorption. • The minimum energy path and the rate-determining step are identified. • The activity of Pt{sub ML}/WC(0001) to CO oxidation is comparable to that of Pt(111). • Some probable strategies are proposed to improve the activity of Pt{sub ML}/WC(0001). - Abstract: The deposition of platinum on the tungsten carbide (Pt/WC) have been achieved and proved with high stability, activity and CO-tolerance toward some reactions in experiments. Although a lot of experimental efforts have been focused on understanding the activity, stability and CO-tolerance of Pt/WC, the relevant theoretical works related to the CO-tolerance mechanism are still scarce. In current study, the adsorption and oxidation of CO on the Pt monolayer supported on WC(0001) surface (Pt{sub ML}/WC(0001)) are investigated using density functional theory calculations. It is found that the oxidation of CO on Pt{sub ML}/WC(0001) proceeds preferably along the Langmuir-Hinshelwood mechanism. The energy barrier of 1.06 eV for the rate-determining step of OOCO formation is almost equal to that (1.05 eV) for CO oxidation by atomic O on Pt(111), while the adsorption energy of 1.59 eV for CO on Pt{sub ML}/WC(0001) is smaller than that on Pt(111) (1.85 eV), indicating that the high resistance to CO poisoning of Pt{sub ML}/WC(0001) may originate from the weak interaction between them. To further improve the CO tolerance, some probable strategies are proposed based on the relevant kinetics results. The current results are helpful to understanding the origin of the highly resistant to CO poisoning of Pt{sub ML}/WC(0001) and rationally designing catalysts to improve the CO oxidation activity.

  5. Mechanical properties of hot-pressed Al-4.5 wt. % Cu/WC composite

    Directory of Open Access Journals (Sweden)

    Samaneh Bernoosi

    2014-12-01

    Full Text Available In this study, the elemental powders of aluminum and copper were initially subjected to mechanical alloying using an attrition ball mill under argon atmosphere to produce an Al-4.5 wt% Cu powder alloy. The WC nanoparticles were then added to the powder alloy and milled in a planetary ball mill to explore the role of the WC nanoparticles on the mechanical properties of the fabricated composite powder. The experimental results revealed that a solid solution of Al-Cu could be formed after MA and a good dispersion of the WC nanoparticles in the aluminum matrix was obtained as characterized using X-ray diffraction and scanning electron microscopy, respectively. The results of hardness and compression tests of the hot pressed composites indicated that the MA followed by the hot-press processes was successful to fabricate an alloy and a metal matrix composite with considerable mechanical properties. However, a decreasing trend in the hardness and strength of the composites with the WC contents of more than 5wt% was observed. The maximum values of 260 HV and 575 MPa were obtained for a composite containing 5 wt% of nano ceramic particles.

  6. Objectively measured sedentary behavior and physical activity in a sample of Finnish adults: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Pauliina Husu

    2016-09-01

    Full Text Available Abstract Background Regular physical activity (PA confers many positive effects on health and well-being. Sedentary behavior (SB, in turn, is a risk factor for health, regardless of the level of moderate to vigorous PA. The present study describes the levels of objectively measured SB, breaks in SB, standing still and PA among Finnish adults. Methods This cross-sectional analysis is based on the sub-sample of the population-based Health 2011 Study of Finnish adults. The study population consisted of 18-to-85-year old men and women who wore a waist-worn triaxial accelerometer (Hookie AM 20 for at least 4 days, for at least 10 h per day (n = 1587 during a week. PA and SB were objectively assessed from the raw accelerometric data using novel processing and analysis algorithms with mean amplitude deviation as the processing method. The data was statistically analyzed using cross-tabulations, analysis of variance and analysis of covariance. Results The participants were on average 52 years old, 57 % being women. Participants were sedentary 59 % of their waking wear time, mainly sitting. They spent 17 % of the time standing still, 15 % in light intensity PA, 9 % in moderate PA and less than 1 % in vigorous PA. Participants aged 30–39 years had the highest number of breaks in SB per day. Younger participants (<30 years of age had more moderate and vigorous PA than older ones (≥60 years of age, and 30–60-year-olds had the greatest amount of light PA. Conclusions Participants spent nearly 60 % of their waking time sedentary, and the majority of their daily PA was light. From a public health perspective it is important to find effective ways to decrease SB as well as to increase the level of PA. Our analysis method of raw accelerometer data may allow more precise assessment of dose-response relationships between objectively measured PA and SB and various indicators of health and well-being.

  7. Physical Activity and Sedentary Behavior Associated with Components of Metabolic Syndrome among People in Rural China.

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    Jing Xiao

    Full Text Available Metabolic syndrome is prevalent worldwide and its prevalence is related to physical activity, race, and lifestyle. Little data is available for people living in rural areas of China. In this study we examined associations of physical activity and sedentary behaviors with metabolic syndrome components among people in rural China.The Nantong Metabolic Syndrome Study recruited 13,505 female and 6,997 male participants between 2007 and 2008. Data of socio-demographic characteristics and lifestyle were collected. The associations of physical activity and sedentary behaviors with metabolic syndrome components were analyzed.Prevalence of metabolic syndrome was 21.6%. It was significantly lower in men than in women. Low risks of metabolic syndrome were observed in those who did less sitting and engaged in more vigorous physical activity. The highest tertile of vigorous physical activity was associated with 15-40% decreased odds of metabolic syndrome and all of its components, except for low high-density lipoprotein cholesterol in men. Women with the highest tertile of moderate physical activity had 15-30% lower odds of central obesity, high glucose, and high triglycerides compared with those in the lowest tertile. Sitting time >42 hours per week had a 4%-12% attributable risk of metabolic syndrome, central obesity, and high triglycerides in both genders, and abnormal glucose and diastolic blood pressure in women. Sleeping for more than 8 hours per day was associated with risk of high serum glucose and lipids.Our data suggested that physical activity has a preventive effect against metabolic syndrome and all its abnormal components, and that longer sitting time and sleep duration are associated with an increased risk of metabolic syndrome components, including central obesity and high triglycerides, glucose, and diastolic blood pressure. This study could provide information for future investigation into these associations. Also, recommendations are

  8. Binder extrusion of sliding wear of WC-Co alloys

    International Nuclear Information System (INIS)

    Larsen-Basse, J.

    1985-01-01

    It has previously been proposed that preferential removal of the cobalt binder is an important mechanism in the abrasive wear of cemented carbides in the WC-Co family. It is here demonstrated that binder extrusion occurs also in metal-to-metal sliding wear contacts. The wear scar generated by sliding a hardened steel ball repeatedly over a polished WC-Co surface was studied by SEM. The extruded cobalt fragments accumulate by surface defects, such as cracks caused by the sliding loaded ball, and gradual microfragmentation of the carbide grains follows. The energy required to extrude the cobalt and cause the gradual change in surface layer microstructure is provided by the frictional forces

  9. Machinability and scratch wear resistance of carbon-coated WC inserts

    Energy Technology Data Exchange (ETDEWEB)

    Pazhanivel, B., E-mail: palcecri@yahoo.co.in; Kumar, T. Prem; Sozhan, G.

    2015-03-15

    Highlights: • Cemented WC inserts were coated with carbon by CVD. • The deposits were either loosely held MWCNTs or adherent carbides. • Co-efficient of friction (ramp load; 1–13 N); 0.2 and 0.1 μ, respectively, for the uncoated and carbide-coated inserts. • The carbide-coated insert exhibited better machinability and surface finish than a commercial TiCN-coated insert. - Abstract: In this work, cemented tungsten carbide (WC) inserts were coated with nanocarbons/carbides by chemical vapor deposition (CVD) and their machinability and scratch wear resistance were investigated. The hardness and surface conditions of the WC substrate were studied before and after coating. The CVD-generated nanocarbons on the insert surfaces were examined by SEM, FE-SEM and TEM. The electron microscopic images revealed that the carbons generated were multi-walled carbon nanotubes (MWCNTs) or carbides depending on the experimental conditions. In both the cases, the cutting edges of the inserts had dense deposits. Scratch wear test with the coated inserts showed that the co-efficient of friction was 0.1 μ as against 0.2 μ for the uncoated inserts under a ramp load of 1–13 N. The machinability characteristics of commercially available TiCN-coated inserts and the carbon-coated WC inserts were compared by using a CNC machine and a Rapid I vision inspection system. It was found that the carbide-coated inserts exhibited machinability with better surface finish comparable to that of the TiCN-coated inserts while the MWCNT-coated inserts showed inferior adhesion properties.

  10. Metallography and quality of dies made from WC-Co cemented carbides; Metallographie und Qualitaetskontrolle von WC-Co-Hartmetallmatrizen

    Energy Technology Data Exchange (ETDEWEB)

    Forejt, M. [Inst. of Technology, Faculty of Mechanical Engineering, Technical Univ., Brno (Czech Republic); Krejcova, J. [Inst. of Technology, Faculty of Mechanical Engineering, Technical Univ., Brno (Czech Republic); Smutna, J. [Inst. of Physics of Materials, ASCR, Brno (Czech Republic); Krejci, J. [Inst. of Physics of Materials, ASCR, Brno (Czech Republic)

    1995-05-01

    As opposite to cutting tools made from cemented carbides, forming tools (dies) seem to be on the periphery of the interest, although specific loading conditions (increased temperature, relatively high strain rate, high pressure and cyclic loading) impose different requirements on the material. The present paper contains results of light and SEM metallography of WC + Co cemented carbide dies used for screw nuts production. Two problems were pursued viz. final preparation of the surface of operative cavity after drilling and defects that appear when recycled cemented carbides are used for die production. (orig.) [Deutsch] Im Gegensatz zu Hartmetall-Schneidwerkzeugen scheinen Formwerkzeuge (Matrizen) nur am Rande des Interesses zu liegen, obwohl hier die spezifischen Beanspruchungsbedingungen (hoehere Temperaturen, relativ hohe Dehnrate, hoher Druck und zyklische Belastung) zu besonderen Anforderungen an den Werkstoff fuehren. Es werden die Ergebnisse der lichtmikroskopischen und REM-Untersuchungen an WC-Co-Hartmetallmatrizen fuer die Mutternherstellung beschrieben. Zwei Themen werden behandelt, und zwar die Endbearbeitung der Formhohlraum-Oberflaeche nach dem Bohren und die Fehler, die durch die Verwendung von Hartmetallschrott fuer die Matrizenherstellung auftreten koennen. (orig.)

  11. Auditing the socio-environmental determinants of motivation towards physical activity or sedentariness in work-aged adults: a qualitative study.

    Science.gov (United States)

    Keegan, Richard; Middleton, Geoff; Henderson, Hannah; Girling, Mica

    2016-05-26

    There is a lack of understanding of work aged adults' (30-60 years old) perspectives on the motivation of physical activity versus sedentariness. This study aims to: (1) identify which socio-environmental factors motivate physical activity and/or sedentary behavior, in adults aged 30-60 years; and (2) explore how these motivators interact and combine. Fifteen work-aged adults who, were able to engage in physical activity (Mean age = 43.9 years; SD 9.6, range 31-59), participated in semi-structured interviews. Inductive content analysis was used to generate an inventory of socio-environmental factors and their specific influences on motivation towards physical activity or sedentariness. Key socio-environmental agents found to influence motivation included: Spouse/partner, parents, children, siblings, whole family, grandchildren, friends, work-mates, neighbors, strangers, team-mates and class-mates, instructors, health care professionals, employers, gyms and health companies, governments, media and social media, cultural norms, and the physical environment. Mechanisms fell into five broad themes of socio-environmental motivation for both physical activity and sedentariness: (1) competence and progress; (2) informational influences, (3) emotional influences, (4) pragmatics and logistics, and (5) relationships. Similar socio-environmental factors were frequently reported as able to motivate both activity and sedentariness. Likewise, individual categories of influence could also motivate both behaviors, depending on context. The findings of this paper 'unpack' theoretical concepts into specific and targeted behavioral recommendations. The data suggested no simple solutions for promoting physical activity or reducing sedentariness, but rather complex and interacting systems surrounding work-aged adults. Findings also suggest that health professionals should be encouraged to support adults' health by examining the socio-environmental motivational influences, or

  12. Higher Household Income and the Availability of Electronic Devices and Transport at Home Are Associated with Higher Waist Circumference in Colombian Children: The ACFIES Study

    OpenAIRE

    Diego Gómez-Arbeláez; Paul A. Camacho; Daniel D. Cohen; Katherine Rincón-Romero; Laura Alvarado-Jurado; Sandra Pinzón; John Duperly; Patricio López-Jaramillo

    2014-01-01

    Background: The current “epidemic” of childhood obesity is described as being driven by modern lifestyles with associated socioeconomic and environmental changes that modify dietary habits, discourage physical activity and encourage sedentary behaviors. Objective: To evaluate the association between household income and the availability of electronic devices and transport at home, and the values of waist circumference (WC), as an indicator of abdominal obesity, in children and adolescents fro...

  13. Exploring the potential role of tungsten carbide cobalt (WC-Co) nanoparticle internalization in observed toxicity toward lung epithelial cells in vitro.

    Science.gov (United States)

    Armstead, Andrea L; Arena, Christopher B; Li, Bingyun

    2014-07-01

    Tungsten carbide cobalt (WC-Co) has been recognized as a workplace inhalation hazard in the manufacturing, mining and drilling industries by the National Institute of Occupational Safety and Health. Exposure to WC-Co is known to cause "hard metal lung disease" but the relationship between exposure, toxicity and development of disease remain poorly understood. To better understand this relationship, the present study examined the role of WC-Co particle size and internalization on toxicity using lung epithelial cells. We demonstrated that nano- and micro-WC-Co particles exerted toxicity in a dose- and time-dependent manner and that nano-WC-Co particles caused significantly greater toxicity at lower concentrations and shorter exposure times compared to micro-WC-Co particles. WC-Co particles in the nano-size range (not micron-sized) were internalized by lung epithelial cells, which suggested that internalization may play a key role in the enhanced toxicity of nano-WC-Co particles over micro-WC-Co particles. Further exploration of the internalization process indicated that there may be multiple mechanisms involved in WC-Co internalization such as actin and microtubule based cytoskeletal rearrangements. These findings support our hypothesis that WC-Co particle internalization contributes to cellular toxicity and suggest that therapeutic treatments inhibiting particle internalization may serve as prophylactic approaches for those at risk of WC-Co particle exposure. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Data linkage between the National Birth Defects Prevention Study and the Occupational Information Network (O*NET) to assess workplace physical activity, sedentary behaviors, and emotional stressors during pregnancy.

    Science.gov (United States)

    Lee, Laura J; Symanski, Elaine; Lupo, Philip J; Tinker, Sarah C; Razzaghi, Hilda; Pompeii, Lisa A; Hoyt, Adrienne T; Canfield, Mark A; Chan, Wenyaw

    2016-02-01

    Knowledge of the prevalence of work-related physical activities, sedentary behaviors, and emotional stressors among pregnant women is limited, and the extent to which these exposures vary by maternal characteristics remains unclear. Data on mothers of 6,817 infants without major birth defects, with estimated delivery during 1997 through 2009 who worked during pregnancy were obtained from the National Birth Defects Prevention Study. Information on multiple domains of occupational exposures was gathered by linking mother's primary job to the Occupational Information Network Version 9.0. The most frequent estimated physical activity associated with jobs during pregnancy was standing. Of 6,337 mothers, 31.0% reported jobs associated with standing for ≥75% of their time. There was significant variability in estimated occupational exposures by maternal age, race/ethnicity, and educational level. Our findings augment existing literature on occupational physical activities, sedentary behaviors, emotional stressors, and occupational health disparities during pregnancy. © 2015 Wiley Periodicals, Inc.

  15. A Hybrid Online Intervention for Reducing Sedentary Behavior in Obese Women

    Directory of Open Access Journals (Sweden)

    Melanie M Adams

    2013-10-01

    Full Text Available Sedentary behavior (SB has emerged as an independent risk factor for cardiovascular disease and type 2 diabetes. While exercise is known to reduce these risks, reducing SB through increases in non-structured PA and breaks from sitting may appeal to obese women who have lower self-efficacy for PA. This study examined effects of a combined face-to-face and online intervention to reduce SB in overweight and obese women. A two-group quasi-experimental study was used with measures taken pre and post. Female volunteers (M age=58.5, SD=12.5 yrs were enrolled in the intervention (n=40 or waitlisted (n=24. The intervention, based on the Social Cognitive Theory, combined group sessions with email messages over 6 weeks. Individualized feedback to support mastery and peer models of active behaviors were included in the emails. Participants self-monitored PA with a pedometer. Baseline and post measures of PA and SB were assessed by accelerometer and self-report. Standard measures of height, weight and waist circumference were conducted. Repeated measures ANOVA was used for analyses. Self-reported SB and light PA in the intervention group (I changed significantly over time [SB, F(1,2= 3.81, p=.03, light PA, F(1,2=3.39, p=.04]. Significant Group x Time interactions were found for light PA, F(1,63=5.22, p=.03, moderate PA, F(1, 63=3.90, p=.05, and for waist circumference, F(1,63=16.0, p=.001. The I group decreased significantly while the comparison group was unchanged. Hybrid computer interventions to reduce SB may provide a non-exercise alternative for increasing daily PA and potentially reduce waist circumference, a risk factor for type 2 diabetes. Consumer-grade accelerometers may aide improvements to PA and SB and should be tested as part of future interventions.

  16. Cross-Sectional Analysis of Levels and Patterns of Objectively Measured Sedentary Time in Adolescent Females

    LENUS (Irish Health Repository)

    Harrington, Deirdre M.

    2011-10-28

    .5 bouts; p < .001) while after school time consisted of shorter bouts < 20 minutes. Conclusions School is highlighted as a particularly sedentary setting for adolescent females. Interventions to decrease sedentary time at school and the use of wearable devices which distinguish posture should be encouraged when examining sedentary patterns and behaviors in this population.

  17. Demographic correlates of screen time and objectively measured sedentary time and physical activity among toddlers: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Valerie Carson

    2017-02-01

    Full Text Available Abstract Background Determining the most important demographic correlates of sedentary behavior and physical activity will help identify the groups of children that are most in need of intervention. Little is known in regards to the demographic correlates of sedentary behavior and physical activity in toddlers (aged 12–35 months, where long-term behavioral patterns may initially be formed. Therefore, the objective of this study was to examine the associations between demographic correlates and specific types of sedentary behavior and physical activity in this age group. Methods Findings are based on 149 toddlers (19.0 ± 1.9 months and their parents (33.7 ± 4.7 years recruited from immunization clinics in Edmonton, Canada as part of the Parents’ Role in Establishing healthy Physical activity and Sedentary behavior habits (PREPS project. Toddlers’ and parental demographic characteristics and toddlers’ television viewing, video/computer games, and overall screen time were measured via the PREPS parental questionnaire. Toddlers’ objectively measured sedentary time and physical activity (light, moderate to vigorous, and total were accelerometer-derived using Actigraph wGT3X-BT monitors. Simple and multiple linear regression models were conducted to examine associations. Results In the multiple linear regression models, toddlers’ age, toddlers’ sex (female versus male, toddlers’ race/ethnicity (other versus European-Canadian/Caucasian, and household income ($50,001 to $100,000 versus > $100,000 were significantly positively associated, and main type of child care (child care center versus parental care was significantly negatively associated with screen time. Similar findings were observed with television viewing, except null associations were observed for toddlers’ sex. Toddlers’ race/ethnicity (other versus European-Canadian/Caucasian was significantly positively associated and main type of child care (child care

  18. The Synthesis of Nanostructured WC-Based Hardmetals Using Mechanical Alloying and Their Direct Consolidation

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    N. Al-Aqeeli

    2014-01-01

    Full Text Available Tungsten carbide- (WC- based hardmetals or cemented carbides represent an important class of materials used in a wide range of industrial applications which primarily include cutting/drilling tools and wear resistant components. The introduction and processing of nanostructured WC-based cemented carbides and their subsequent consolidation to produce dense components have been the subject of several investigations. One of the attractive means of producing this class of materials is by mechanical alloying technique. However, one of the challenging issues in obtaining the right end-product is the possible loss of the nanocrystallite sizes due to the undesirable grain growth during powder sintering step. Many research groups have engaged in multiple projects aiming at exploring the right path of consolidating the nanostructured WC-based powders without substantially loosing the attained nanostructure. The present paper highlights some key issues related to powder synthesis and sintering of WC-based nanostructured materials using mechanical alloying. The path of directly consolidating the powders using nonconventional consolidation techniques will be addressed and some light will be shed on the advantageous use of such techniques. Cobalt-bonded hardmetals will be principally covered in this work along with an additional exposure of the use of other binders in the WC-based hardmetals.

  19. Genotoxicity of tungsten carbide-cobalt (WC-Co) nanoparticles in vitro: mechanisms-of-action studies.

    Science.gov (United States)

    Moche, Hélène; Chevalier, Dany; Vezin, Hervé; Claude, Nancy; Lorge, Elisabeth; Nesslany, Fabrice

    2015-02-01

    We showed previously that tungsten carbide-cobalt (WC-Co) nanoparticles (NP) can be used as a nanoparticulate positive control in some in vitro mammalian genotoxicity assays. Here, we investigate the mechanisms of action involved in WC-Co NP genotoxicity in L5178Y mouse lymphoma cells and primary human lymphocytes, in vitro. Data from the micronucleus assay coupled with centromere staining and from the chromosome-aberration assay show the involvement of both clastogenic and aneugenic events. Experiments with the formamidopyrimidine DNA glycosylase (FPG)-modified comet assay showed a slight (non-significant) increase in FPG-sensitive sites in the L5178Y mouse lymphoma cells but not in the human lymphocytes. Electron paramagnetic resonance spin-trapping results showed the presence of hydroxyl radicals (•OH) in WC-Co NP suspensions, with or without cells, but with time-dependent production in the presence of cells. However, a significant difference in •OH production was observed between human lymphocytes from two different donors. Using H2O2, we showed that WC-Co NP can participate in Fenton-like reactions. Thus, •OH might be produced either via intrinsic generation by WC-Co NP or through a Fenton-like reaction in the presence of cells. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Why older adults spend time sedentary and break their sedentary behaviour: a mixed methods approach using life-logging equipment

    Directory of Open Access Journals (Sweden)

    Manon L Dontje

    2015-10-01

    It can be concluded that a mixed methods approach, by combining objective data of an activity monitor with contextual information from time-lapse photos and subjective information from people regarding their own behaviour, is an useful method to provide indepth information about (breaking sedentary behaviour in older adults. The results of this study showed that there is a difference in what older adults believe that are reasons for them to remain sedentary or break their sedentary time and what their actual reasons are. A personal story board based on objective measurements of sedentary behaviour can be a useful method to raise awareness and find individual and tailored ways to reduce sedentary behaviour and to increase the number of breaks in sedentary behaviour without much interference in daily routine.