Aerobic exercise and cold pressor test induce hypoalgesia in active and inactive men and women

DEFF Research Database (Denmark)

Vægter, Henrik Bjarke; Handberg, Gitte; Jørgensen, Maria N.

2015-01-01

). Conditioned pain modulation (CPM) was assessed by cold pressor testing. Exercise-induced hypoalgesia (EIH) was assessed after 15 minutes bicycling at a heart rate corresponding to 75% VO2max. A control session of 15 minutes quiet rest was also included. Pressure pain thresholds (PPTs) were recorded...... and after exercise, PPTs increased to the same degree in active and inactive subjects, and the CPM and EIH responses were correlated (P CPM response immediately after cold pressor test was maintained in women but not in men. CONCLUSIONS: Cold pressor stimulation and aerobic exercise caused...... comparable multisegmental increases in PPT in active and inactive men and women. The CPM and EIH responses were correlated, but they have different temporal manifestation of hypoalgesia....

Optimal Test Characteristics for Maximal Anaerobic Work on the Bicycle Ergometer

Science.gov (United States)

Katch, Victor; And Others

1977-01-01

Data from two separate experiments conducted to ascertain the optimum protocol for a maximum anaerobic work output test on the bicycle ergometer indicated that the test duration needs to be approximately forty seconds and the optimal frictional resistance five to six kilograms. (MB)

Growth hormone, prolactin and cortisol response to exercise in patients with depression

DEFF Research Database (Denmark)

Krogh, Jesper; Nordentoft, Merete; Mohammad-Nezhad, Mahdi

2010-01-01

BACKGROUND: A blunted growth hormone and prolactin response to pharmacological stress test have previously been found in depressed patients, as well as an increased cortisol response to psychosocial stress. This study investigated these hormones in response to acute exercise using an incremental...... bicycle test. METHOD: A cross-sectional comparison of cortisol, growth hormone, and prolactin in depressed (n=137) and healthy (n=44) subjects during rest and in response to an incremental bicycle test. Secondly, we tested the depressed patients again after a 4-month randomized naturalistic exercise...... intervention. RESULTS: Resting plasma levels of growth hormone (GH), cortisol, or prolactin (PRL) did not differ between depressed and healthy subjects (all p-values>.12). In response to an incremental bicycle test the GH (p=.02) and cortisol (p=.05) response in depressed was different compared to healthy...

Comparison of the effect of different intensity exercise on a bicycle ergometer on postprandial lipidemia in type II diabetic patients

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Narges Argani

2014-05-01

Full Text Available BACKGROUND: Postprandial lipid clearance failure and lipoprotein disorders, which are independent risk factors for cardiovascular diseases are well-recognized in type II diabetes. Reduction of fats through exercise has been proved, though the mechanism is not well-defined, and the effects of different intensity exercise on postprandial lipidemia in diabetes type II is unknown. This study aims to find these effects using a cycle ergometer. METHODS: On three different days, 15 type II diabetics (10 women and 5 men, with a mean age 42.07 ± 6.05 years, weight 94.64 ± 4.37 kg, height 159.78 ± 9.09 cm, and body mass index 29.83 ± 3.93 kg/m2, consumed a full fat breakfast (750-800 kcal, 85% fat, and 150 min later, blood samples were taken from them to measure their lipid profile. The 1st day was the control day, without any exercises. Seven days later, 90 min after enriched breakfast, they did 30 min of exercise on the cycle ergometer with intensity of 55-70% of maximum heart rate (HRmax, and 14 days later, 90 min after enriched breakfast, they did 30 min of exercise with intensity of 70-85% of HRmax. RESULTS: According to Friedman non-parametric test, high-density lipoprotein (HDL cholesterol serum level significantly increased after 30 min of moderate intensity exercise (P > 0.05, from 39.4 ± 5.2 to 48.6 ± 9.3, while this increase was insignificant after a higher intensity exercise. Neither intensity levels had any significant effects on triglyceride or on low-density lipoprotein cholesterol. CONCLUSION: Results showed that moderate intensity exercise was more effective in increasing HDL cholesterol level in type II diabetics.   Keywords: Postprandial Lipidemia, Resistance Exercise, Bicycle Ergometer, Type II Diabetes 

Arm exercise-thallium imaging testing for the detection of coronary artery disease

International Nuclear Information System (INIS)

Balady, G.J.; Weiner, D.A.; Rothendler, J.A.; Ryan, T.J.

1987-01-01

Patients with lower limb impairment are often unable to undergo a standard bicycle or treadmill test for the evaluation of coronary artery disease. To establish an alternative method of testing, 50 subjects (aged 56 +/- 10 years) performed arm ergometry testing in conjunction with myocardial thallium scintigraphy. All underwent coronary angiography; significant coronary artery disease (greater than or equal to 70% stenosis) in at least one vessel was present in 41 (82%) of the 50 patients. Thallium scintigraphy was found to have an 83% sensitivity and 78% specificity for detecting coronary disease, compared with a sensitivity and specificity of 54% (p less than 0.01) and 67% (p = NS), respectively, for exercise electrocardiography. In the subgroup of 23 patients who had no prior myocardial infarction or left bundle branch block and were not taking digitalis, thallium scintigraphy had a sensitivity of 80% versus 50% for exercise electrocardiography. Scintigraphy yielded a sensitivity of 84, 74 and 90% for one, two and three vessel disease, respectively. Noninvasive arm ergometry exercise-thallium imaging testing appears to be reliable and useful and should be considered in the evaluation of coronary artery disease in patients with lower limb impairment

Gastroenteropancreatic hormonal changes during exercise

DEFF Research Database (Denmark)

Hilsted, J; Galbo, H; Sonne, B

1980-01-01

Peripheral plasma concentrations of gastroenteropancreatic peptides were measured during a 3-h period of bicycle exercise at 40% of maximal oxygen uptake in six normal men. Marked increases (P......Peripheral plasma concentrations of gastroenteropancreatic peptides were measured during a 3-h period of bicycle exercise at 40% of maximal oxygen uptake in six normal men. Marked increases (P...

Utilizing the Bicycle for Non-Traditional Activities

Science.gov (United States)

Maina, Michael P.; Maina, Julie Schlegel; Sebek, Ludek; Hoffmanova, Jana; Kane, Jennifer Jackson

2012-01-01

This article examines the bicycle as not simply a means of transportation or as an exercise device, but rather as a vehicle for teambuilding and problem solving activities within a physical education curriculum. The activities described in this article focus on bike-centered initiatives that foster creative problem solving. They have universal…

SENAM AEROBIC EXERCISER CHI MACHINE LEBIH EFEKTIF DARIPADA BERSEPEDA STATIS MENURUNKAN KADAR GULA DARAH PADA PASIEN DIABETES MELLITUS TIPE II DI PUSKESMAS MENGWI III

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I Wayan Surasta

2013-11-01

Full Text Available Diabetes mellitus is a metabolic syndrome with hyperglycemic in characteristic. Exercise is one of intervention hopefully curing diabetes mellitus. The objective of the study was to analyze effect of aerobic exerciser chi- machine  and static bicycle   reducing of blood glucose level type 2 diabetes mellitus. Design   of study quasi eksperiment, pre test and post test control group design. Group 1 (10 samples was provided   aerobic exercise chi-machine and group 2 (10 samples static bicycle   15 minutes three time a week the duration of six weeks. Study  locati was at Mengwi III  Public Health Center, of Badung Regency with 20 samples was selected by using simple random sampling from the patient of diabetes mellitus type 2. Result of study is showed  aerobic exerciser chi-machine reduced the mean of blood glucose level of 124 mg%. Static bicycle  reduced mean of blood glucose level of 70.4 mg%. Conclusion of study aerobic exercise chi-machine more effective 17% than static bicycle exercise (p: 0,028 for reducing of blood glucose level type 2 diabetes mellitus.  

Spontaneous baroreflex sensitivity estimates during graded bicycle exercise: a comparative study

International Nuclear Information System (INIS)

Vallais, Frederic; Baselli, Giuseppe; Lucini, Daniela; Pagani, Massimo; Porta, Alberto

2009-01-01

In the literature, several methods have been proposed for the assessment of the baroreflex sensitivity from spontaneous variability of heart period and systolic arterial pressure. The present study compares the most utilized approaches for the evaluation of the spontaneous baroreflex sensitivity (i.e. sequence-based, spectral, cross-spectral and model-based techniques) over a protocol capable of inducing a progressive decrease of the baroreflex sensitivity in the presence of a relevant respiratory drive (i.e. a stepwise dynamic bicycle exercise at 10%, 20% and 30% of the maximum nominal individual effort) in 16 healthy humans. Results demonstrated that the degree of correlation among the estimates is related to the structure of the model explicitly or implicitly assumed by the method and depends on the experimental condition (i.e. on the physiological mechanisms contemporaneously active with baroreflex, e.g. cardiopulmonary reflexes). However, even in the presence of a significant correlation, proportional and/or constant biases can be present, thus rendering spontaneous baroreflex estimates not interchangeable. We suggest that the comparison among different baroreflex sensitivity estimates might elucidate physiological mechanisms responsible for the relationship between heart period and systolic arterial pressure

Cardiopulmonary Exercise Testing in Patients with Idiopathic Scoliosis.

Science.gov (United States)

Shen, Jianxiong; Lin, Youxi; Luo, Jinmei; Xiao, Yi

2016-10-05

Scoliosis causes impairment of the respiratory and cardiovascular systems. Traditional pulmonary function tests only examine patients under static conditions. The aim of our study was to investigate the correlation between radiographic parameters and dynamic cardiopulmonary capacity in patients with idiopathic scoliosis. Forty patients with idiopathic scoliosis were included in this prospective study from January 2014 to February 2016. The patients underwent full radiographic assessment of deformity, pulmonary function testing, and cardiopulmonary bicycle ergometer testing. The impact of the severity of thoracic curvature and kyphosis on pulmonary function and physical capacity was investigated. Thirty-three female patients with a mean age of 15.5 years (range, 11 to 35 years) and coronal thoracic curvature of 49.4° (range, 24° to 76°) and 7 male subjects with a mean age of 15.9 years (range, 13 to 18 years) and coronal thoracic curvature of 47.1°(range, 22° to 80°) were included. No correlation was found between coronal thoracic curvature and pulmonary function test results in the female patients. Female patients with a thoracic curve of ≥60° had lower blood oxygen saturation at maximal exercise in the cardiopulmonary exercise test (p = 0.032). Female patients with a thoracic curve of ≥50° had a higher respiratory rate (p = 0.041) and ventilation volume per minute (p = 0.046) and lower breathing reserve at maximal exercise (p = 0.038). Thoracic kyphosis in female patients was positively correlated with pulmonary function, as shown by the forced expiratory volume in 1 second (r = 0.456, p = 0.01), forced vital capacity (r = 0.366, p = 0.043), vital capacity (r = 0.525, p = 0.006), and total lung capacity (r = 0.388, p = 0.031), as well as with tidal volume (r = 0.401, p = 0.025) in cardiopulmonary exercise testing. Female patients who engaged in regular exercise had better peak oxygen intake normalized by body weight (p rate (p = 0.020), and heart rate

Modeling of speed distribution for mixed bicycle traffic flow

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Cheng Xu

2015-11-01

Full Text Available Speed is a fundamental measure of traffic performance for highway systems. There were lots of results for the speed characteristics of motorized vehicles. In this article, we studied the speed distribution for mixed bicycle traffic which was ignored in the past. Field speed data were collected from Hangzhou, China, under different survey sites, traffic conditions, and percentages of electric bicycle. The statistics results of field data show that the total mean speed of electric bicycles is 17.09 km/h, 3.63 km/h faster and 27.0% higher than that of regular bicycles. Normal, log-normal, gamma, and Weibull distribution models were used for testing speed data. The results of goodness-of-fit hypothesis tests imply that the log-normal and Weibull model can fit the field data very well. Then, the relationships between mean speed and electric bicycle proportions were proposed using linear regression models, and the mean speed for purely electric bicycles or regular bicycles can be obtained. The findings of this article will provide effective help for the safety and traffic management of mixed bicycle traffic.

An Analyses of Bicycle Accidents in Ankara: Analyses of 5 Years

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Muhittin Yilmaz

2014-12-01

Full Text Available Aim: Bicycles are used for transportation, exercise and recreation. In this study we aimed to investigate the epidemiological, clinical and economic aspects of bicycle injuries. Material and Method: We included in the study who admitted to the Emergency Department with a bicycle accident between January 2008 and July 2012. Patient age and sex, accident pattern, presence of personal protective measures, injured body part, Glasgow Coma Scale (GCS score, Revised Trauma Score (RTS, radiological findings, requested consultations, duration of hospital stay, season of injury, and average cost rates were recorded. The study population was divided into 2 age groups as 0-14 years and over 14 years. Results: A patients were 238 (81.2% male and their mean age was 31.5±14.1 years. Fifty-five (18.8% patients were female and their mean age was 34.5±15.9 years. Males had significantly higher rate of bicycle injury (p

Vision-Based Bicycle Detection Using Multiscale Block Local Binary Pattern

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Hongyu Hu

2014-01-01

Full Text Available Bicycle traffic has heavy proportion among all travel modes in some developing countries, which is crucial for urban traffic control and management as well as facility design. This paper proposes a real-time multiple bicycle detection algorithm based on video. At first, an effective feature called multiscale block local binary pattern (MBLBP is extracted for representing the moving object, which is a well-classified feature to distinguish between bicycles and nonbicycles; then, a cascaded bicycle classifier trained by AdaBoost algorithm is proposed, which has a good computation efficiency. Finally, the method is tested with video sequence captured from the real-world traffic scenario. The bicycles in the test scenario are successfully detected.

The effects of three different type of exercises on aerobic and anaerobic power

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Gorucu Alpaslan

2017-08-01

Full Text Available Purpose: The study was conducted with the aim of investigating the effects of three different types of exercise: bicycling, plyometric and weight on aerobic and anaerobic power. Material: Sample size 30 students recreational athletes aged 23,19 years. The athletes were divided into 3 groups of 10 subjects (bicycle, plyometric, weight. The program for 6 weeks included: 3 different exercises planned for 30 minute/3 days/week. Body weight, vertical jump and 20-meter shuttle running tests were measured for each group. Statistical analysis was performed by SPSS21.0: arithmetic averages and standard deviations; the Kruskal-Wallis H test was used to determine the differences between the groups; the Mann-Whitney U test was used to determine the group which result in the difference among the groups; Wilcoxon 's t test was used to determine pretest posttest differences within the groups. Results: As a result of the research, it was determined that the increase in the aerobic power levels of the bicycle and plyometric groups was significant (p0.05. Conclusions: The different exercises practiced by all three groups significantly increased anaerobic power levels. When the aerobic and anaerobic power values of the three groups in each study were examined, it was found that only the increase of weight and plyometric groups was high level in favor of the weight group in terms of posttest aerobic power.

Comparison of hemodynamics during hyperthermal immersion and exercise testing in apparently healthy females aged 50-60 years.

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Lietava, Jan; Vohnout, Branislav; Valent, Denis; Celko, Juraj

2004-07-01

Owing to excessive worries regarding adverse cardiac events, hyperthermal balneotherapy for patients with coronary artery disease is underprescribed. However, very few cardiac events occur in similar heat stress during Finnish sauna bathing. Exercise testing has proven to be a safe diagnostic procedure even in survivors of myocardial infarction. We compared the effects of hyperthermal immersion and exercise testing on cardiac hemodynamics in 21 apparently healthy women aged 50-60 years. The maximal symptom-limited bicycle exercise test was performed according to the modified protocol of Wasserman. Hyperthermal immersion was carried out in 40 degrees C water and was completed by increasing the core temperature by about 2 degrees C. The left ventricular function was evaluated using continuous measurement of thoracic electric bioimpedance during both tests. The blood pressure, index of contractility and heart rate were measured directly, whereas the cardiac index, left cardiac work index and systemic vascular resistance index were calculated. The hemodynamic response, as assessed at continuous non-invasive monitoring, showed substantial differences between hyperthermal immersion and exercise testing. Overall, we found a significantly lower hemodynamic load during hyperthermal immersion in comparison with exercise testing. Entering the bath, there was a significant decrease in the left cardiac work, contractility and blood pressure. We recorded a slight increase in the heart rate towards peak hyperthermal immersion. However, other modulators such as the mean arterial pressure, index of contractility, cardiac index and left cardiac work index decreased even below resting values. Excessive hyperthermal immersion induced a lower hemodynamic load in apparently healthy women than standard maximal exercise testing.

No effect of glycogen level on glycogen metabolism during high intensity exercise

DEFF Research Database (Denmark)

Vandenberghe, Katleen; Hespel, P.; Eynde, Bart Vanden

1995-01-01

, either for 1 min 45 s (protocol 1; N = 18) or to exhaustion (protocol 2; N = 14). The exercise tests were preceded by either 5 d on a controlled normal (N) diet, or by 2 d of glycogen-depleting exercise accompanied by the normal diet followed by 3 d on a carbohydrate-rich (CHR) diet. In protocol 1......This study examined the effect of glycogen supercompensation on glycogen breakdown, muscle and blood lactate accumulation, blood-pH, and performance during short-term high-intensity exercise. Young healthy volunteers performed two supramaximal (125% of VO2max) exercise tests on a bicycle ergometer...

In-depth analysis of bicycle hydraulic disc brakes

Science.gov (United States)

Maier, Oliver; Györfi, Benedikt; Wrede, Jürgen; Arnold, Timo; Moia, Alessandro

2017-10-01

Hydraulic Disc Brakes (HDBs) represent the most recent and innovative bicycle braking system. Especially Electric Bicycles (EBs), which are becoming more and more popular, are equipped with this powerful, unaffected by environmental influences, and low-wear type of brakes. As a consequence of the high braking performance, typical bicycle braking errors lead to more serious accidents. This is the starting point for the development of a Braking Dynamics Assistance system (BDA) to prevent front wheel lockup and nose-over (falling over the handlebars). One of the essential prerequisites for the system design is a better understanding of bicycle HDBs' characteristics. A physical simulation model and a test bench have been built for this purpose. The results of the virtual and real experiments conducted show a high correlation and allow valuable insights into HDBs on bicycles, which have not been studied scientifically in any depth so far.

Favorable effect of aerobic exercise on arterial pressure and aortic pulse wave velocity during stress testing.

Science.gov (United States)

Milatz, Florian; Ketelhut, Sascha; Ketelhut, Sascha; Ketelhut, Reinhard G

2015-07-01

Increased central pulse wave velocity is a major risk factor for cardiovascular disease. The favorable influence of exercise on arterial stiffness (AS) and blood pressure (BP) has been reported exclusively at rest. The present study investigated the influence of a single bout of acute cycling on AS and BP during recovery and, moreover, during cold pressor stress testing. 32 healthy men (33.7 ± 8 years, BMI 24 ± 2.5 kg/m²) performed a 60 minute endurance exercise on a bicycle ergometer (45 % VO2max). Before and after exercise aortic pulse wave velocity (aPWV) as well as central and peripheral BP were measured non-invasively at rest and at the end of a 2 minute cold pressor test (CPT). Even after 60 minutes of recovery aPWV (- 0.22 ± 0.3 m / sec) was significantly reduced (p Exercise decreased peripheral (- 8 ± 7 mmHg) and central (- 7 ± 8 mmHg) systolic BP as well as peripheral (- 3 ± 5 mmHg) and central (- 4 ± 7 mmHg) diastolic BP (p exercise, there was a significant reduction in aPWV (- 0.19 ± 0.3 m / sec), peripheral (- 6 ± 10 mmHg) and central (- 5 ± 8 mmHg) systolic BP as well as peripheral (- 3 ± 6 mmHg) and central (- 3 ± 6 mmHg) diastolic BP during CPT after exercise (p exercise leads not only to decreased BP but even more reduces aPWV as a measure of AS even after 60 minutes of recovery. In particular, the investigation provides evidence that acute moderate-intensity exercise has a favorable effect on BP and aPWV during stress testing.

Bicycle: a bioinformatics pipeline to analyze bisulfite sequencing data.

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Graña, Osvaldo; López-Fernández, Hugo; Fdez-Riverola, Florentino; González Pisano, David; Glez-Peña, Daniel

2018-04-15

High-throughput sequencing of bisulfite-converted DNA is a technique used to measure DNA methylation levels. Although a considerable number of computational pipelines have been developed to analyze such data, none of them tackles all the peculiarities of the analysis together, revealing limitations that can force the user to manually perform additional steps needed for a complete processing of the data. This article presents bicycle, an integrated, flexible analysis pipeline for bisulfite sequencing data. Bicycle analyzes whole genome bisulfite sequencing data, targeted bisulfite sequencing data and hydroxymethylation data. To show how bicycle overtakes other available pipelines, we compared them on a defined number of features that are summarized in a table. We also tested bicycle with both simulated and real datasets, to show its level of performance, and compared it to different state-of-the-art methylation analysis pipelines. Bicycle is publicly available under GNU LGPL v3.0 license at http://www.sing-group.org/bicycle. Users can also download a customized Ubuntu LiveCD including bicycle and other bisulfite sequencing data pipelines compared here. In addition, a docker image with bicycle and its dependencies, which allows a straightforward use of bicycle in any platform (e.g. Linux, OS X or Windows), is also available. ograna@cnio.es or dgpena@uvigo.es. Supplementary data are available at Bioinformatics online.

Validity of a device designed to measure braking power in bicycle disc brakes.

Science.gov (United States)

Miller, Matthew C; Fink, Philip W; Macdermid, Paul William; Perry, Blake G; Stannard, Stephen R

2017-07-21

Real-world cycling performance depends not only on exercise capacities, but also on efficiently traversing the bicycle through the terrain. The aim of this study was to determine if it was possible to quantify the braking done by a cyclist in the field. One cyclist performed 408 braking trials (348 on a flat road; 60 on a flat dirt path) over 5 days on a bicycle fitted with brake torque and angular velocity sensors to measure brake power. Based on Newtonian physics, the sum of brake work, aerodynamic drag and rolling resistance was compared with the change in kinetic energy in each braking event. Strong linear relationships between the total energy removed from the bicycle-rider system through braking and the change in kinetic energy were observed on the tar-sealed road (r 2  = 0.989; p brake torque and angular velocity sensors are valid for calculating brake power on the disc brakes of a bicycle in field conditions. Such a device may be useful for investigating cyclists' ability to traverse through various terrains.

Fat utilization during exercise

DEFF Research Database (Denmark)

Helge, Jørn Wulff; Watt, Peter W.; Richter, Erik

2001-01-01

1. This study was carried out to test the hypothesis that the greater fat oxidation observed during exercise after adaptation to a high-fat diet is due to an increased uptake of fat originating from the bloodstream. 2. Of 13 male untrained subjects, seven consumed a fat-rich diet (62 % fat, 21...... % carbohydrate) and six consumed a carbohydrate-rich diet (20 % fat, 65 % carbohydrate). After 7 weeks of training and diet, 60 min of bicycle exercise was performed at 68 +/- 1 % of maximum oxygen uptake. During exercise [1-(13)C]palmitate was infused, arterial and venous femoral blood samples were collected......, and blood flow was determined by the thermodilution technique. Muscle biopsy samples were taken from the vastus lateralis muscle before and after exercise. 3. During exercise, the respiratory exchange ratio was significantly lower in subjects consuming the fat-rich diet (0.86 +/- 0.01, mean +/- S.E.M.) than...

The role of cardiopulmonary exercise test for individualized exercise training recommendation in young obese subjects

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Lucian Hoble

2010-06-01

Full Text Available Obesity is affecting a growing segment of the population and should be considered a serious health problem which will lead to medical complications and decreased life span. Lifestyle changes by adopting healthy food and increase energy consumption through physical activity is the most important treatment for obesity. Cardiopulmonary exercise test (CPET is considered the gold standard for exercise capacity assessment. Purpose: This study is aiming to demonstrate that individualized exercise training programs, designed using CPET results, leads to increase of physical fitness, aerobic capacity, ventilatory and cardiac exercise performance in young obese subjects.Material and method:We performed a prospective research study of 6 months. 43 sedentary subjects without contraindications to exercise, 21.3±3.1 years old, 93% female were included in the study. Assessments were made at baseline and after six months of intervention and consists of cardiopulmonary exercise test on bicycle ergometer. After we recorded oxygen uptake at aerobic threshold (AT, anaerobic threshold (in the range of respiratory compensation point – RCP and maximal oxygen uptake (VO2max we designed the training program according to these parameters and individualized heart rate training zones of each subject. Exercise training (60 minutes/session, 3 sessions/week was performed taking in consideration the training zones and using a circuit on cardio devices. Each subject was supervised by a physiotherapist and using heart rate monitors. The number of subjects evaluated at the end of the study was 27 (dropout rate 37%.Results:After six months of intervention we noticed an improvement of maximum oxygen uptake (VO2max (from 22.7±3.69 to 27.44±5.55, aerobic threshold (VO2_AT (from 15.48±2.66 to 20.07±4.64 ml/min/kg, p<0.0001 and anaerobic threshold (VO2_RCP (from 20.3±3.66 to 25.11±5.84 ml/min/kg, p<0.0001, cardiac performance during exercise evaluated trough maximal oxygen

Depression and Anxiety: Exercise Eases Symptoms

Science.gov (United States)

... make a difference. It may take less time exercising to improve your mood when you do more-vigorous activities, such as running or bicycling. The mental health benefits of exercise and physical activity may last only ...

Relationship between the Pedaling Biomechanics and Strain of Bicycle Frame during Submaximal Tests

OpenAIRE

Manolova, Aneliya; Crequy, Samuel; Lestriez, Philippe; Debraux, Pierre; Bertucci, William

2015-01-01

The aim of this study was to analyse the effect of forces applied to pedals and cranks on the strain imposed to an instrumented bicycle motocross (BMX) frame. Using results from a finite element analysis to determine the localisation of highest stress, eight strain gauges were located on the down tube, the seat tube and the right chain stay. Before the pedaling tests, static loads were applied to the frame during bench tests. Two pedaling conditions have been analysed. In the first, the rider...

Teaching children about bicycle safety: an evaluation of the New Jersey Bike School program.

Science.gov (United States)

Lachapelle, Ugo; Noland, Robert B; Von Hagen, Leigh Ann

2013-03-01

There are multiple health and environmental benefits associated with increasing bicycling among children. However, the use of bicycles is also associated with severe injuries and fatalities. In order to reduce bicycle crashes, a bicycling education program was implemented in selected New Jersey schools and summer camps as part of the New Jersey Safe Routes to School Program. Using a convenience sample of participants to the program, an opportunistic study was designed to evaluate the effectiveness of two bicycle education programs, the first a more-structured program delivered in a school setting, with no on-road component, and the other a less structured program delivered in a summer camp setting that included an on-road component. Tests administered before and after training were designed to assess knowledge acquired during the training. Questions assessed children's existing knowledge of helmet use and other equipment, bicycle safety, as well as their ability to discriminate hazards and understand rules of the road. Participating children (n=699) also completed a travel survey that assessed their bicycling behavior and their perception of safety issues. Response to individual questions, overall pre- and post-training test scores, and changes in test scores were compared using comparison of proportion, t-tests, and ordinary least-squares (OLS) regression. Improvements between the pre-training and post-training test are apparent from the frequency distribution of test results and from t-tests. Both summer camps and school-based programs recorded similar improvements in test results. Children who bicycled with their parents scored higher on the pre-training test but did not improve as much on the post-training test. Without evaluating long-term changes in behavior, it is difficult to ascertain how successful the program is on eventual behavioral and safety outcomes. Copyright © 2012 Elsevier Ltd. All rights reserved.

Several submaximal exercise tests are reliable, valid and acceptable in people with chronic pain, fibromyalgia or chronic fatigue: a systematic review.

Science.gov (United States)

Ratter, Julia; Radlinger, Lorenz; Lucas, Cees

2014-09-01

Are submaximal and maximal exercise tests reliable, valid and acceptable in people with chronic pain, fibromyalgia and fatigue disorders? Systematic review of studies of the psychometric properties of exercise tests. People older than 18 years with chronic pain, fibromyalgia and chronic fatigue disorders. Studies of the measurement properties of tests of physical capacity in people with chronic pain, fibromyalgia or chronic fatigue disorders were included. Studies were required to report: reliability coefficients (intraclass correlation coefficient, alpha reliability coefficient, limits of agreements and Bland-Altman plots); validity coefficients (intraclass correlation coefficient, Spearman's correlation, Kendal T coefficient, Pearson's correlation); or dropout rates. Fourteen studies were eligible: none had low risk of bias, 10 had unclear risk of bias and four had high risk of bias. The included studies evaluated: Åstrand test; modified Åstrand test; Lean body mass-based Åstrand test; submaximal bicycle ergometer test following another protocol other than Åstrand test; 2-km walk test; 5-minute, 6-minute and 10-minute walk tests; shuttle walk test; and modified symptom-limited Bruce treadmill test. None of the studies assessed maximal exercise tests. Where they had been tested, reliability and validity were generally high. Dropout rates were generally acceptable. The 2-km walk test was not recommended in fibromyalgia. Moderate evidence was found for reliability, validity and acceptability of submaximal exercise tests in patients with chronic pain, fibromyalgia or chronic fatigue. There is no evidence about maximal exercise tests in patients with chronic pain, fibromyalgia and chronic fatigue. Copyright © 2014. Published by Elsevier B.V.

Cardiopulmonary exercise testing – effective method for evaluation and recommendation of individualized exercise training in patients with metabolic syndrome

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Claudiu Avram

2011-12-01

Full Text Available The present study aims to emphasize the role of cardiopulmonary exercise training (CPET in evaluation and recommendation of individualized exercise training in patients with a metabolic syndrome. Methods: We performed a prospective longitudinal study of 9 months. The study group consisted of 28 young patients (21.3±3.1 years old without contraindications to exercise, previously diagnosed with metabolic syndrome according to NCEP-ATPIII criteria. All patients were evaluating at baseline and after 3 months of intervention and at the end of the study (after 9 months. The evaluation consists in performing a CPET on bicycle ergometer in which subjects were monitored in terms of cardiac and respiratory parameters. The CPET results allow us to establish the range of effort intensity in which the patient should exercise in order to burn calories and achieve the maximum fat oxidation rate. All patients benefit from an intensive interval exercise training programme, supervised and guided by a physical therapist. Exercise training consisted in 50 minutes sessions, 3 times per week, at intensive endurance training zone (in the range of anaerobic threshold, completed by 1 minute interval in the range between anaerobic threshold (AT and respiratory compensation point (RCP, for every 5 minutes of training. Results: After 9 months of intervention we noticed an improvement of abdominal obesity (waist circumference decreased from 98.98±10.14 cm to 89.54±12.32 cm, p<0.001, physical fitness (V’O2peak increased from 1.83±0.33 l/min to 2.13±0.4 l/min, p<0.001 and endurance (Oxygen uptake in the range of anaerobic treshold increase from 1.27±0.27 l/min to 1.55±0.31 l/min, p<0.001. Conclusions: Cardiopulmonary exercise testing together with training zones determinations is a useful tool for assessing the exercise capacity and drawing up individual workouts. Active and closely monitored intervention by individualized exercise training programmes leads to

The Bicycle Drawing Test: What Does It Measure in Developmentally Typical Children?

Science.gov (United States)

Cannoni, Eleonora; Di Norcia, Anna; Bombi, Anna Silvia; Di Giunta, Laura

2015-10-01

To verify the dimensionality of Bicycle Drawing Test (BDT), we applied the coding system of Greenberg, Rodriguez, and Sesta to bicycle drawings made by 295 boys and 320 girls (6-10 years old) with typical development, and submitted the data to item analysis, exploratory factor analysis, and confirmatory factor analysis. These analyses confirmed only two of the original four dimensions of the BDT: spatial reasoning and visual-motor control. The scores in these two factors were correlated with the Colored Progressive Matrices, the Rey Complex Figure (Copy and Memory) and with the teachers' ratings in mathematics, language, and drawing. The correlations, albeit moderate in magnitude, were consistent with the hypothesized convergent and discriminant validity. After checking for measurement invariance across gender and age, we conducted two analyses of variance, the first of which showed a significant difference between younger children (6-8 years old) and older children (9-10 years old); the analysis of variance by gender did not yield significant differences. These data enhance the usefulness of the BDT as a measure of separate cognitive components, but do not support its use as a measure of mechanical reasoning. © The Author(s) 2014.

Effects of different modes of exercise on appetite and appetite-regulating hormones.

Science.gov (United States)

Kawano, Hiroshi; Mineta, Mayuko; Asaka, Meiko; Miyashita, Masashi; Numao, Shigeharu; Gando, Yuko; Ando, Takafumi; Sakamoto, Shizuo; Higuchi, Mitsuru

2013-07-01

The present study determined the changes in appetite and appetite-regulating gut hormones during and following bouts of both rope skipping exercise (weight-bearing) and bicycle ergometer exercise (non-weight-bearing). After a 12-h fast, 15 young men (mean ± SD, age 24.4 ± 1.7 yrs, maximal oxygen uptake 47.0 ± 6.5 mL/kg/min) participated in three 160 min trials: (1) rope skipping exercise (295 ± 40 kcal, 3 sets × 10 min with 5-min interval, then rested for 120 min); (2) bicycle ergometer exercise (288 ± 36 kcal, 3 sets × 10 min with 5-min interval, then rested for 120 min); (3) control (rested for 160 min). Ratings of perceived hunger and acylated ghrelin were suppressed and total peptide YY (PYY) were increased during and immediately after exercise in both exercise trials, but glucagon liked peptide-1 was not changed. Furthermore, suppressed hunger during rope skipping exercise was greater than that during bicycle ergometer exercise, but there were no differences in acylated ghrelin and total PYY. These results indicate that weight-bearing exercise has a greater exercise-induced appetite suppressive effect compared with non-weight-bearing exercise, and both forms of exercise lowered acylated ghrelin and increased total PYY, but the changes did not differ significantly between exercise modes. Copyright © 2013 Elsevier Ltd. All rights reserved.

The false positive exercise test

International Nuclear Information System (INIS)

Moritani, Kohshiro; Matsuda, Yasuo; Ozaki, Masaharu; Ogawa, Hiroshi; Ichiyama, Masaji; Matsuda, Masako; Kusukawa, Reizo

1986-01-01

Exercise tests with sublingual nitroglycerin were performed on 7 patients with true positive and 8 patients with false positive exercise test results. Four of 7 patients with true positive changes and 8 patients with false positive changes underwent exercise cardiac scintigraphy. Scintigrams showed perfusion defects in 4 patients with true positive outcomes, and no perfusion defect in 8 patients with false positive outcomes. Exercise tests with sublingual nitroglycerin were performed with the same load as that without nitroglycerin. In all 7 patients with true positive exercise test results, ST segment depression observed in the control exercise test was not observed in the nitroglycerin exercise test. In the false positive patients, ST segment depression observed in the control exercise test remained unchanged in 7 of 8 patients receiving nitroglycerin. Exercise tests with sublingual nitroglycerin as well as exercise cardiac scintigraphy are valuable tods in differentiating false positive from true positive patients. Furthermore, these data suggest that ST segment depression in the false positive patients may not be related to myocardial ischemia. (author)

Detection of cardiovascular autonomic neuropathy using exercise testing in patients with type 2 diabetes mellitus.

Science.gov (United States)

Banthia, Smriti; Bergner, Daniel W; Chicos, Alexandru B; Ng, Jason; Pelchovitz, Daniel J; Subacius, Haris; Kadish, Alan H; Goldberger, Jeffrey J

2013-01-01

This study investigated autonomic nervous system function in subjects with diabetes during exercise and recovery. Eighteen type 2 diabetics (age 55±2 years) and twenty healthy controls (age 51±1 years) underwent two 16-min bicycle submaximal ECG stress tests followed by 45 min of recovery. During session #2, atropine (0.04 mg/kg) was administered at peak exercise, and the final two minutes of exercise and entire recovery occurred under parasympathetic blockade. Plasma catecholamines were measured throughout. Parasympathetic effect was defined as the difference between a measured parameter at baseline and after parasympathetic blockade. The parasympathetic effect on the RR interval was blunted (P=.004) in diabetic subjects during recovery. Parasympathetic effect on QT-RR slope during early recovery was diminished in the diabetes group (diabetes 0.13±0.02, control 0.21±0.02, P=.03). Subjects with diabetes had a lower heart rate recovery at 1 min (diabetes 18.5±1.9 bpm, control 27.6±1.5 bpm, Pdiabetes, even with minimal evidence of CAN using current methodology, altered cardiac autonomic balance is present and can be detected through an exercise-based assessment for CAN. The early post-exercise recovery period in diabetes was characterized by enhanced sympathoexcitation, diminished parasympathetic reactivation and delay in heart rate recovery. Copyright © 2013 Elsevier Inc. All rights reserved.

Exercise left ventricular performance in patients with chest pain, ischemic-appearing exercise electrocardiograms, and angiographically normal coronary arteries

International Nuclear Information System (INIS)

Berger, H.J.; Sands, M.J.; Davies, R.A.; Wackers, F.J.; Alexander, J.; Lachman, A.S.; Williams, B.W.; Zaret, B.L.

1981-01-01

Left ventricular performance was evaluated using first-pass radionuclide angiocardiography in 31 patients with chest pain, an ischemic-appearing exercise electrocardiogram, and angiographically normal coronary arteries at rest and during maximal upright bicycle exercise. 201 Tl imaging was done in all patients after treadmill exercise and in selected patients after ergonovine provocation. Resting left ventricular performance was normal in all patients. An abnormal ejection fraction response to exercise was detected in 12 of 31 patients. Regional dysfunction was present during exercise in four patients, all of whom also had abnormal global responses. Three of these 12 patients and two additional patients had exercise-induced 201 Tl perfusion defects. In all nine patients who underwent ergonovine testing, there was no suggestion of coronary arterial spasm. Thus, left ventricular dysfunction during exercise, in the presence of normal resting performance, was found in a substantial number of patients with chest pain, an ischemic-appearing exercise electrocardiogram, and normal coronary arteries

Pilocarpine iontophoresis test

DEFF Research Database (Denmark)

Hjortskov, N; Jepsen, Leif; Nielsen, B

1995-01-01

The pilocarpine iontophoresis test (P-test) is used as a predictor of the capacity to produce sweat. Therefore, we studied the reproducibility of this test in 12 normal subjects on 10 consecutive days. Furthermore, we determined whether the P-test reflects whole-body and regional sweat secretion...... during exercise in the heat. Finally, we determined whether the P-test stimulates the eccrine sweat glands to maximal sweat secretion. Six growth hormone-deficient (GHD) patients who are known to have decreased sweating, and 11 healthy control subjects were studied. To induce maximal sweat secretion......, the patients exercised on a bicycle ergometer at a workload corresponding to 40% of their maximal aerobic power (VO2max). The 11 healthy subjects exercised at a workload of 150 W. All subjects exercised for 60 min in ambient air at 35 degrees C, with 50% relative humidity. The P-test showed a mean day...

Long-term bicycle riding ameliorates the depression of the patients undergoing hemodialysis by affecting the levels of interleukin-6 and interleukin-18

Directory of Open Access Journals (Sweden)

Zhao C

2016-12-01

Full Text Available Chunhui Zhao, Hui Ma, Lei Yang, Yong Xiao Blood Purification Center, The First Affiliated Hospital of Dalian Medical University, Dalian, People’s Republic of China Purpose: Hemodialysis patients with depression have a higher risk of death and hospitalization. Although there is pharmacological management for the depression of hemodialysis patients, the adverse effect of the drug limits the use. The nonpharmacological way, bicycle riding, may be an effective way for the therapy of the depression in hemodialysis patients. However, the underlying mechanism of this relationship is still not fully explained, while interleukin-6 (IL-6 and interleukin-18 (IL-18 are associated with depression and exercise. Thus, the effects of bicycle riding on the levels of the interleukin were explored. Participants and methods: One hundred and eighty-nine patients with chronic hemodialysis were selected and randomly assigned to three groups of medicine (MG, received 20-mg escitalopram daily, medicine and aerobic exercise (MAG, received 20-mg escitalopram daily and bicycle riding six times weekly, and only aerobic exercise (AG, received 20-mg placebo daily and bicycle riding six times weekly. The whole experiment lasted for 18 weeks. The quality of life (36-Item Short Form Health Survey and depression severity according to criteria in the Diagnostic and Statistical Manual of Mental Disorders, fourth edition [DSM-IV] were measured before and at the end of this study. The serum levels of IL-6 and IL-18 were measured by an enzyme-linked immunosorbent assay kit. Results: The quality of life was improved and depression severity was reduced significantly in the MAG and AG groups when compared with the MG group (P<0.05. Serum levels of IL-6 and IL-18 were the highest in the MG group, moderate in the MAG group and the lowest in AG group. On the other hand, the serum levels of IL-6 and IL-18 were closely associated with depression scores (P<0.05. Conclusion: Aerobic exercise

Head-to-head comparison of peak supine bicycle exercise echocardiography and treadmill exercise echocardiography at peak and at post-exercise for the detection of coronary artery disease.

Science.gov (United States)

Peteiro, Jesús; Bouzas-Mosquera, Alberto; Estevez, Rodrigo; Pazos, Pablo; Piñeiro, Miriam; Castro-Beiras, Alfonso

2012-03-01

Supine bicycle exercise (SBE) echocardiography and treadmill exercise (TME) echocardiography have been used for evaluation of coronary artery disease (CAD). Although peak imaging acquisition has been considered unfeasible with TME, higher sensitivity for the detection of CAD has been recently found with this method compared with post-TME echocardiography. However, peak TME echocardiography has not been previously compared with the more standardized peak SBE echocardiography. The aim of this study was to compare peak TME echocardiography, peak SBE echocardiography, and post-TME echocardiography for the detection of CAD. A series of 116 patients (mean age, 61 ± 10 years) referred for evaluation of CAD underwent SBE (starting at 25 W, with 25-W increments every 2-3 min) and TME with peak and postexercise imaging acquisition, in a random sequence. Digitized images at baseline, at peak TME, after TME, and at peak SBE were interpreted in a random and blinded fashion. All patients underwent coronary angiography. Maximal heart rate was higher during TME, whereas systolic blood pressure was higher during SBE, resulting in similar rate-pressure products. On quantitative angiography, 75 patients had coronary stenosis (≥50%). In these patients, wall motion score indexes at maximal exercise were higher at peak TME (median, 1.45; interquartile range [IQR], 1.13-1.75) than at peak SBE (median, 1.25; IQR, 1.0-1.56) or after TME (median, 1.13; IQR, 1.0-1.38) (P = .002 between peak TME and peak SBE imaging, P peak TME (median, 5; IQR, 2-12) compared with peak SBE (median, 3; IQR, 0-8) or after TME (median, 2; IQR, 0-4) (P peak TME and peak SBE imaging, P peak TME, peak SBE, and post-TME echocardiography for CAD was 84%, 75%, and 60% (P = .001 between post-TME and peak TME echocardiography, P = .055 between post-TME and peak SBE echocardiography), with specificity of 63%, 80%, and 78%, respectively (P = NS) and accuracy of 77%, 77%, and 66%, respectively (P = NS). Peak TME

Bicycle-Related Shoulder Injuries: Etiology and the Need for Protective Gear.

Science.gov (United States)

Goldstein, Yariv; Dolkart, Oleg; Kaufman, Ehud; Amar, Eyal; Sharfman, Zachary T; Rath, Ehud; Mozes, Gavriel; Maman, Eran

2016-01-01

The popularity of bicycle riding for recreation, exercise and transportation has grown enormously in recent years, which has led to an increased incidence of bicycle-related injuries. While these injuries involve mainly the musculoskeletal system, data on shoulder-specific injuries incurred while bike riding are lacking. Classifying these shoulder injuries may provide insight and assistance in the creation and implementation of effective protective gear and measures. To investigate the types and mechanisms of shoulder injuries among cyclists. This study retrospectively examined all cyclists who incurred shoulder injuries while riding and were admitted to the emergency department and shoulder clinic between January 2008 and November 2013. The study included 157 subjects with various bicycle-related shoulder injuries treated with either conservative or surgical measures. Eighty-four percent of injuries were caused by a direct blow to the shoulder, 7% by falling on an outstretched hand, 6% were traction injuries, and 3% were due to hyperabduction. Nine different clinical types of injury were observed; the most common injuries were clavicle fractures (32%), followed by acromioclavicular joint dislocations (22%), rotator cuff tears (22%), and humeral fractures (8%). Fifty-one percent of subjects were managed with conservative care and the remaining patients required surgical interventions. Shoulder injuries incurred while riding a bicycle span the entire spectrum of shoulder injuries and often result in debilitating conditions. Although the use of helmets is increasing, there is currently no effective protective gear or measures to prevent riders from suffering shoulder injuries.

SPORT AND EXERCISE PHYSIOLOGY TESTING Volume one: Sport Testing Volume two: Exercise and Clinical Testing

Directory of Open Access Journals (Sweden)

Edward M. Winter

2007-03-01

Full Text Available DESCRIPTION The objective of the book is to discuss the theoretical and practical aspects of physiological testing in exercise and sports which is essential to evaluate and monitor developing exercise performance for athletes and public health, and improving quality of life for patients.A board of leading sport and exercise physiologists and scientists are gathered to discuss physiological assessments that have proven validity and reliability, both in sport and health relevant issues. Incidentally, it updates the reader about the current subjects of physiological exertion testing in both research and clinical procedures. Both volumes individually cover the increasing number of available research and review publications, and theoretical explanations are supported by practical examples. A step-by-step and/or checklist method is used in appropriate sections which make the guides more user-friendly than most. PURPOSE The first volume is designed to help readers develop an understanding of the essential concepts of sport specific testing whereas the second volume aims at making the exercise and clinical specific testing comprehensible, dealing with both technical terms and the theories underlying the importance of these tests. AUDIENCE As Guidelines books of the British Association of Sport and Exercise Sciences, it will be of interest to a wide range of students, researchers and practitioners in the sport and exercise disciplines whether they work in the laboratory or in the field. FEATURES The first volume features immediate practical requirements particularly in sport testing. It is composed of five parts with detailed sub-sections in all of them. The topics of the parts are: i general principles, ii methodological issues, iii general procedures, iv sport specific procedures, v special populations.The second volume is also presented in five parts, again with sub-sections in all of them, but considering the requirements in clinical and exercise

"Graded Cycling Test with Talk Test" Is a Reliable Test to Monitor Cardiovascular Fitness in Patients with Minor Stroke

DEFF Research Database (Denmark)

Steen Krawcyk, Rikke; Vinther, Anders; Caesar Petersen, Nicolas

2017-01-01

variability may challenge currently used cardiovascular monitoring. The Graded Cycling Test with Talk Test is a submaximal exercise test independent of heart rate variability, shown reliable for patients with cardiac disease. METHODS: Patients diagnosed with lacunar stroke according to TOAST (Trial of Org...... a minor measurement error: 12.9 W for groups of patients (standard error of measurement, SEM95) and 18.3 W for individual patients (smallest real difference). CONCLUSION: The "Graded Cycling Test with Talk Test" is feasible and reliable for monitoring exercise effects in patients with lacunar stroke...... 10172 in Acute Stroke Treatment) criteria performed an incremental exercise test on a stationary bicycle with a 15 W (watt) increase in workload every minute. Toward the end of each incremental step, the patients recited a standardized text passage and subsequently were asked: "Are you still able...

Improvement of exercise capacity and left ventricular diastolic function with metoprolol XL after acute myocardial infarction

DEFF Research Database (Denmark)

Poulsen, S H; Jensen, S E; Egstrup, K

2000-01-01

dysfunction after acute myocardial infarction were given metoprolol XL (n = 29) or placebo (n = 30). The effects of metoprolol XL on exercise capacity in relation to effects on LV diastolic filling were studied. Two-dimensional Doppler echocardiography and maximal symptom limited bicycle test were performed...

Interrelation of ST-segment depression during bicycle ergometry and extent of myocardial ischaemia by myocardial perfusion SPECT

International Nuclear Information System (INIS)

Muzzarelli, Stefano; Pfisterer, Matthias Emil; Zellweger, Michael Johannes; Mueller-Brand, Jan

2009-01-01

The aim of this study was to compare ST-segment depression (STD) during bicycle ergometry and extent of myocardial ischaemia assessed by myocardial perfusion SPECT (MPS) in a large patient cohort. Consecutive patients (n = 955) referred for MPS with bicycle ergometry and interpretable stress ECG were evaluated with respect to ECG and MPS findings of ischaemia. The maximal STD was recorded and exercise ECG was considered ischaemic if STD was horizontal or downsloping (≥1 mm). MPS was interpreted using a 20-segment model with a scale of 0 to 4. A summed stress (SSS), summed rest (SRS) and summed difference score (SDS = SSS-SRS, e.g. extent of ischaemia) were derived. Ischaemia was defined as an SDS ≥ 2. An exercise-induced STD was present in 215 patients (22%) and myocardial ischaemia on MPS was present in 366 patients (38%). The extent of ST-segment depression and the number of ECG leads with significant STD were each strongly and significantly associated with increasing severity of ischaemia and the number of coronary territories involved (p < 0.01 for all correlations). These data demonstrate a strong correlation between the extent of STD, number of ischaemic leads and severity of myocardial ischaemia as assessed by MPS during bicycle ergometry. (orig.)

Interrelation of ST-segment depression during bicycle ergometry and extent of myocardial ischaemia by myocardial perfusion SPECT

Energy Technology Data Exchange (ETDEWEB)

Muzzarelli, Stefano; Pfisterer, Matthias Emil; Zellweger, Michael Johannes [University Hospital Basel, Cardiology Department, Basel (Switzerland); Mueller-Brand, Jan [University Hospital Basel, Nuclear Medicine Department, Basel (Switzerland)

2009-11-15

The aim of this study was to compare ST-segment depression (STD) during bicycle ergometry and extent of myocardial ischaemia assessed by myocardial perfusion SPECT (MPS) in a large patient cohort. Consecutive patients (n = 955) referred for MPS with bicycle ergometry and interpretable stress ECG were evaluated with respect to ECG and MPS findings of ischaemia. The maximal STD was recorded and exercise ECG was considered ischaemic if STD was horizontal or downsloping ({>=}1 mm). MPS was interpreted using a 20-segment model with a scale of 0 to 4. A summed stress (SSS), summed rest (SRS) and summed difference score (SDS = SSS-SRS, e.g. extent of ischaemia) were derived. Ischaemia was defined as an SDS {>=} 2. An exercise-induced STD was present in 215 patients (22%) and myocardial ischaemia on MPS was present in 366 patients (38%). The extent of ST-segment depression and the number of ECG leads with significant STD were each strongly and significantly associated with increasing severity of ischaemia and the number of coronary territories involved (p < 0.01 for all correlations). These data demonstrate a strong correlation between the extent of STD, number of ischaemic leads and severity of myocardial ischaemia as assessed by MPS during bicycle ergometry. (orig.)

Aerobic Exercise Training Improves Orthostatic Tolerance in Aging Humans.

Science.gov (United States)

Xu, Diqun; Wang, Hong; Chen, Shande; Ross, Sarah; Liu, Howe; Olivencia-Yurvati, Albert; Raven, Peter B; Shi, Xiangrong

2017-04-01

This study was designed to test the hypothesis that aerobic exercise training of the elderly will increase aerobic fitness without compromising orthostatic tolerance (OT). Eight healthy sedentary volunteers (67.0 ± 1.7 yr old, four women) participated in 1 yr of endurance exercise training (stationary bicycle and/or treadmill) program at the individuals' 65%-75% of HRpeak. Peak O2 uptake (V˙O2peak) and HRpeak were determined by a maximal exercise stress test using a bicycle ergometer. Carotid baroreceptor reflex (CBR) control of HR and mean arterial pressure (MAP) were assessed by a neck pressure-neck suction protocol. Each subject's maximal gain (Gmax), or sensitivity, of the CBR function curves were derived from fitting their reflex HR and MAP responses to the corresponding neck pressure-neck suction stimuli using a logistic function curve. The subjects' OT was assessed using lower-body negative pressure (LBNP) graded to -50 mm Hg; the sum of the product of LBNP intensity and time (mm Hg·min) was calculated as the cumulative stress index. Training increased V˙O2peak (before vs after: 22.8 ± 0.92 vs 27.9 ± 1.33 mL·min·kg, P stress index was increased from 767 ± 68 mm Hg·min pretraining to 946 ± 44 mm Hg·min posttraining (P Aerobic exercise training improved the aerobic fitness and OT in elderly subjects. An improved OT is likely associated with an enhanced CBR function that has been reset to better maintain cerebral perfusion and cerebral tissue oxygenation during LBNP.

An integrated approach to bicycle safety.

NARCIS (Netherlands)

Wittink, R.D.

1997-01-01

The advantages of cycling are outlined, as well as the conditions under which use of the bicycle and the safety of cycling can he promoted. Bicycles are an attractive product. The potential to use a bicycle for trips shorter than 5 km is high and it's use can also be substantial for longer

Bilateral tension pneumothorax resulting from a bicycle-to-bicycle collision.

Science.gov (United States)

Edwin, Frank; Sereboe, Lawrence; Tettey, Mark Mawutor; Aniteye, Ernest; Bankah, Patrick; Frimpong-Boateng, Kwabena

2009-01-01

Bilateral tension pneumothorax occurring as a result of recreational activity is exceedingly rare. A 10-year-old boy with no previous respiratory symptoms was involved in a bicycle-to-bicycle collision during play. He was the only one hurt. A few hours later, he was rushed to the general casualty unit of the emergency department of our institution with respiratory distress, diminished bilateral chest excursions and diminished breath sounds. The correct diagnosis was made after a chest radiograph was obtained in the course of resuscitation at the casualty unit. Pleural space needle decompression was suggestive of tension only on the right. Bilateral tube thoracostomies provided effective relief. He was discharged from hospital after a week in excellent health. This case illustrates the need for children to have safety instruction to reduce the risks of recreational bicycling. Chest radiography may be needed to establish the diagnosis of bilateral tension pneumothorax. Needle thoracostomy decompression is not always effective.

Automated and connected vehicle (AV/CV) test bed to improve transit, bicycle, and pedestrian safety : concept of operations plan.

Science.gov (United States)

2017-02-01

This document presents the Concept of Operations (ConOps) Plan for the Automated and Connected Vehicle (AV/CV) Test Bed to Improve Transit, Bicycle, and Pedestrian Safety. As illustrated in Figure 1, the plan presents the overarching vision and goals...

Double product response and diastolic blood pressure in treadmill, stationary bicycle and muscular circuit exercises

Directory of Open Access Journals (Sweden)

Elmiro Santos Resende

2006-06-01

Full Text Available Among the various causes for cardiovascular problems affecting the world population nowadays, the most relevant risk factors is sedentary lifestyle. Many studies have been carried out to analyse and elucidate main adaptations on the cardiovascular system stimulated by different sorts of exercises.In this way, this study had aimed at comparing the acute response of double product (DP and diastolic blood pressure (DBP after treadmill (TRM, stationary bicycle (BIC or muscle circuit training (MCT exercises. Nine individuals (6 women and 3 men exercised at 60% of heart rate reserve (HRR on the TRM and BIC and at 60% of one repetition maximum (1RM in MCT. The results showed that pre- and post-effort DP were significantly difference in all three exercises. However, DP did not differ among exercise types. The hypotensive DBP pos-effort response was greater in MCT. According to the results, it was concluded that there is no difference on the heart work demand rate estimated by DP among the three exercises and MCT at 60% 1RM provokes a greater hypotensive DBP post-effort response. RESUMO Entre as diversas causas de problemas cardiovasculares que afetam a população mundial, na atualidade, o sedentarismo é apontado como um dos fatores de risco mais relevantes. Vários estudos têm se preocupado em analisar e esclarecer as principais adaptações provocadas pelos diferentes tipos de exercícios sobre o sistema cardiovascular. Seguindo esta linha o presente trabalho teve como objetivo analisar e comparar a resposta aguda do duplo produto (DP e a pressão arterial diastólica (PAD em exercício de esteira, bicicleta estacionária e circuito na musculação. Foram avaliados nove indivíduos sendo seis mulheres e três homens, na esteira, a 60% da freqüência cardíaca de reserva (FCR, na bicicleta estacionária, a 60% FCR e circuito de musculação a 60% de 1 repetição máxima (1RM. Os resultados encontrados apresentaram diferença significativa do DP pr

Double product response and diastolic blood pressure in treadmill, stationary bicycle and muscular circuit exercises

Directory of Open Access Journals (Sweden)

Leandro Teixeira Paranhos Lopes

2006-08-01

Full Text Available Among the various causes for cardiovascular problems affecting the world population nowadays, the most relevant risk factors is sedentary lifestyle. Many studies have been carried out to analyse and elucidate main adaptations on the cardiovascular system stimulated by different sorts of exercises.In this way, this study had aimed at comparing the acute response of double product (DP and diastolic blood pressure (DBP after treadmill (TRM, stationary bicycle (BIC or muscle circuit training (MCT exercises. Nine individuals (6 women and 3 men exercised at 60% of heart rate reserve (HRR on the TRM and BIC and at 60% of one repetition maximum (1RM in MCT. The results showed that pre- and post-effort DP were significantly difference in all three exercises. However, DP did not differ among exercise types. The hypotensive DBP pos-effort response was greater in MCT. According to the results, it was concluded that there is no difference on the heart work demand rate estimated by DP among the three exercises and MCT at 60% 1RM provokes a greater hypotensive DBP post-effort response. . Resumo Entre as diversas causas de problemas cardiovasculares que afetam a população mundial, na atualidade, o sedentarismo é apontado como um dos fatores de risco mais relevantes. Vários estudos têm se preocupado em analisar e esclarecer as principais adaptações provocadas pelos diferentes tipos de exercícios sobre o sistema cardiovascular. Seguindo esta linha o presente trabalho teve como objetivo analisar e comparar a resposta aguda do duplo produto (DP e a pressão arterial diastólica (PAD em exercício de esteira, bicicleta estacionária e circuito na musculação. Foram avaliados nove indivíduos sendo seis mulheres e três homens, na esteira, a 60% da freqüência cardíaca de reserva (FCR, na bicicleta estacionária, a 60% FCR e circuito de musculação a 60% de 1 repetição máxima (1RM. Os resultados encontrados apresentaram diferença significativa do DP

Exercise tolerance in asymptomatic patients with moderate-severe valvular heart disease and preserved ejection fraction.

Science.gov (United States)

Olaf, Schulz; Debora, Brala; Ricarda, Bensch; Gunnar, Berghöfer; Jochen, Krämer; Schimke, Ingolf; Halle, Martin; Jaffe, Allan

2012-12-20

For asymptomatic patients with moderate-severe valvular heart disease, in whom symptoms may be obscured, objective exercise tolerance measures are warranted for decisions concerning physical activities and surgical treatment. We compared 61 patients (39 with aortic stenosis, 22 with aortic or mitral regurgitation) to 23 controls without valvular heart disease but with indications for stress testing. All participants underwent cardiopulmonary function testing and dobutamine stress echocardiography. Blood was drawn before as well as after bicycle stress to assess high-sensitivity cardiac troponin T (hscTnT). Patients who underwent surgery were re-evaluated 1.5 ±0.9 years after the operation. Conventional bicycle test following guideline criteria revealed a pathologic result in 26% of the patients, whereas spiroergometry showed an objectively reduced exercise tolerance in 59%, reaching a prognostically relevant feature in 39%. Stress echocardiography detected a reduced systolic reserve in 33% and elevated filling pressures in 62%. These abnormalities were significantly less present in the control group (4, 17, 9, 9, 4% respectively, p valvular heart disease beyond stress-test criteria recommended in recent guidelines. High-sensitivity cardiac troponin I may be of additional value. Results of these tests presage post-operative function.

Bicycle Purchaser Training Workshop.

Science.gov (United States)

Schwarz, William

A course was developed to provide data to buyers of new bicycles so they could make an informed decision about their purchases. The instructional systems design process (analysis, design, development, implementation, and evaluation) was used to analyze the need for a training course on buying and fitting a bicycle. Information was collected…

Bicycle Safety in Action.

Science.gov (United States)

National Commission on Safety Education, Washington, DC.

This material was designed to assist schools in teaching bicycle safety. As the population grows and competition for road space increases, it is more imperative than ever that we concentrate attention on the need for caution among pupil cyclists. The pamphlet: (1) discusses the role of bicycle safety in classroom instruction and in student…

Bicycle urbanism as competitive advantage in the neoliberal age

DEFF Research Database (Denmark)

Ibsen, Mikkel Elkær; Olesen, Kristian

2018-01-01

In the light of the emergent ‘bicycle renaissance’ in the US, this paper analyses the rationale basis of bicycle role model, Portland’s promotion of bicycling. By conceptualizing bicycle promotion as a ‘travelling idea’, the paper discusses the key rationales and discourses structuring how bicycl...

Does pedalling on a recumbent bicycle influence the cyclist’s steering behaviour?

NARCIS (Netherlands)

Boon, K.M.; Klap, P.; Van Lanen, J.A.; Letsoin, G.J.; Jansen, A.J.

2014-01-01

The paper presents the answer to the question how pedalling on a specific recumbent bicycle, such as the VeloX3, influences a cyclist’s ability to steer the bicycle. The research aims to find the correlation between pedalling and the undesired steering movements it creates. To test this assumption a

Lipolysis in human adipose tissue during exercise

DEFF Research Database (Denmark)

Lange, Kai Henrik Wiborg; Lorentsen, Jeanne; Isaksson, Fredrik

2002-01-01

exercise), as well as during non-steady-state (onset of exercise and early exercise) experimental settings. Fourteen healthy women [age: 74 +/- 1 (SE) yr] were studied at rest and during 60-min continuous bicycling at 60% of peak O(2) uptake. Calculated and measured subcutaneous abdominal adipose tissue...... venous glycerol concentrations increased substantially from rest to exercise but were similar both at rest and during later stages of exercise. In contrast, during the initial approximately 40 min of exercise, calculated glycerol concentration was significantly lower (approximately 40%) than measured...... and continuous prolonged exercise. However, during shorter periods of exercise (

Effects of rehydration and food consumption on salivary flow, pH and buffering capacity in young adult volunteers during ergometer exercise.

Science.gov (United States)

Tanabe, Mai; Takahashi, Toshiyuki; Shimoyama, Kazuhiro; Toyoshima, Yukako; Ueno, Toshiaki

2013-10-28

The aim of this study was to investigate the influences of rehydration and food consumption on salivary flow, pH, and buffering capacity during bicycle ergometer exercise in participants. Ten healthy volunteers exercised on a bicycle ergometer at 80% of their maximal heart rate. These sessions lasted for two periods of 20 min separated by 5-min rest intervals. Volunteers were subjected to one of the following conditions: (1) no water (mineral water) or food consumption, (2) only water for rehydration, (3) water and food consumption, (4) a sports drink only for rehydration, and (5) rehydration with a sports drink and food. Statistical significance was assessed using one-way analysis of variance and Dunnett's test (p salivary pH decreased significantly during and after exercise in conditions 4 and 5. The salivary buffering capacity decreased significantly during exercise and/or after the exercise in conditions 1, 3, 4, and 5. The results showed that salivary pH and buffering capacity decreased greatly depending on the combination of a sports drink and food.

Cardiovascular health benefits of some locally adoptable exercise ...

African Journals Online (AJOL)

... access the much evidence based benefit of exercise on cardiovascular health because they hold the believe that effective exercise can only be done in the organized gymnasium. We compared the cardiovascular effect of riding bicycle ergometer, a commonly used gymnasium equipment with that of jogging and walking ...

Road accidents involving bicycles: configurations and injuries.

Science.gov (United States)

Orsi, Chiara; Montomoli, Cristina; Otte, Dietmar; Morandi, Anna

2017-12-01

This study analyzed the most common types of accident involving bicycles and compared the frequency of injuries. The data source was the database of German In-Depth Accident Study (GIDAS). Cases consist of bicycles and their riders involved in accidents between 2000 and 2010. In most collisions, the bicycle impacted with a car. The percentage of injured bicyclists was higher in collisions with a heavy vehicle and decreased when the bicycle impacted with lighter vehicles. A high percentage of injured bicyclists in single accidents was observed; the most severe injury was more frequently to head and extremities. Accidents involving a car and a bicycle with the right of way in a bicycle path represented about 20% of involved and injured bicyclists. The ten most frequent configurations represented about 60% of involved and injured bicyclists. These results contribute to understand the dangerous scenarios for bicyclists and to suggest preventive actions.

Design and analysis of sustainable paper bicycle

Science.gov (United States)

Roni Sahroni, Taufik; Nasution, Januar

2017-12-01

This paper presents the design of sustainable paper bicycle which describes the stage by stage in the production of paper bicycle. The objective of this project is to design a sustainable paper bicycles to be used for children under five years old. The design analysis emphasizes in screening method to ensure the design fulfil the safety purposes. The evaluation concept is presented in designing a sustainable paper bicycle to determine highest rating. Project methodology is proposed for developing a sustainable paper bicycle. Design analysis of pedal, front and rear wheel, seat, and handle were presented using AutoCAD software. The design optimization was performed to fulfil the safety factors by modifying the material size and dimension. Based on the design analysis results, it is found that the optimization results met the factor safety. As a result, a sustainable paper bicycle was proposed for children under five years old.

[Exercise laryngoscopy: a new method for the differential diagnosis of dyspnea on exertion].

Science.gov (United States)

Tervonen, Hanna; Iljukov, Sergei; Niskanen, Minna-Liisa; Vilkman, Erkki; Sovijärvi, Anssi; Aaltonen, Leena-Maija

2011-01-01

Exertional dyspnea originating from the laryngeal level can be established with certainty only if the paradoxical vocal cord adduction is observed during dyspnea. We have developed a novel diagnostic method, exercise laryngoscopy, which involves observation of the larynx with a flexible endoscope applied via the nose during a bicycle ergometry test. It has been our aim to improve the differential diagnosis of dyspnea on exertion and thus also reduce unnecessary antiasthmatic medication. Exercise laryngoscopy allows examination in the out-patient clinics because the method is well tolerated.

Comparative life cycle assessment of ghana-made bamboo-frame bicycle and conventional bicycles assembled and used in the Netherlands

NARCIS (Netherlands)

Agyekum, E.O.; Fortuin, K.P.J.; Harst, van der E.J.M.

2014-01-01

In order to assess the sustainability of bamboo-framed bicycles produced in Ghana, an environmental and social life cycle assessments (LCA) were performed. For the environmental LCA, a bamboo-frame bicycle was compared with aluminium- and steel-frame bicycles, focussing on processes related to the

Exercise-Stress Echocardiography Reveals Systolic Anterior Motion of the Mitral Valve as a Cause of Syncopes in a Cardiac Amyloidosis Patient

DEFF Research Database (Denmark)

Clemmensen, Tor Skibsted; Mølgaard, Henning; Andersen, Niels Frost

2016-01-01

increased left ventricular outflow track (LVOT) velocity. However, bicycle exercise-stress test with simultaneous echocardiography revealed a stepwise decrease in blood pressure, a substantial increase in the LVOT velocity, and severe systolic anterior motion of the mitral valve. The patients' symptoms were...

Carbohydrate- and protein-rich diets in McArdle disease: Effects on exercise capacity

DEFF Research Database (Denmark)

Andersen, S.T.; Vissing, J.

2008-01-01

metabolism during exercise, which questions the effect of protein in McArdle disease. METHODS: In a crossover, open design, we studied 7 patients with McArdle disease, who were randomised to follow either a carbohydrate- or protein-rich diet for three days before testing. Caloric intake on each diet...... was identical, and was adjusted to the subject's weight, age and sex. After each diet, exercise tolerance and maximal work capacity were tested on a bicycle ergometer, using a constant workload for 15 minutes followed by an incremental workload to exhaustion. RESULTS: During the constant workload, heart rate...... capacity and exercise tolerance to submaximal workloads by maintaining a diet high in carbohydrate instead of protein. The carbohydrate diet not only improves tolerance to every-day activities, but will likely also help to prevent exercise-induced episodes of muscle injury in McArdle disease Udgivelsesdato...

Bicycle traffic in urban areas

Directory of Open Access Journals (Sweden)

Anđelković Zorica

2015-01-01

Full Text Available Cycling is a term describing the use of bicycles, but also any mean of transport driven solely by human power. Development of bicycle traffic in urban areas involves construction of cycling infrastructure, adapting streets and other traffic infrastructure to a form suitable for cycling and other means of transport (individual motorized traffic, public transport, walking, ensuring the adequate budget and systematic planning and development of sustainable transport in cities. The paper presents basic settings and conditions as input elements to plan bicycle traffic in urban areas, as well as program- design conditions which lead the activities of planners and designers of urban roads in connection with cyclists.

More pronounced effect of acute exercise-induced increase in circulating inflammatory markers in obese compared to lean subjects

DEFF Research Database (Denmark)

Christiansen, Tore; Paulsen, Søren Kildeberg; Bruun, Jens Meldgaard

2010-01-01

in circulation, and on gene expression on these infammatory marker in skeletal muscle (SM) and adipose tissue (AT) biopsies. Material and Methods: 15 lean males and females (BMI 22.4±2 kg/m2) and 16 obese males and females (BMI 31.6±3 kg/m2) exercised for 120 minutes by ergometer bicycling at moderate intensity......Objective: Exercise modulates the immune system and in young males acute exercise has been found associated with increased systemic level of infam-matory markers such as IL-6 and IL-8. In this study we investigated the impact of obesity on the exercise induced release of infammatory markers...... (55-60% of maximal heart rate). Blood samples were obtained at baseline (T0), after 60 minutes of bicycling (T=60), after 120 minutes of bicycling (T=120), whereas biopsies from AT and SM were obtained at T0 and T120. Results: Divided into weight-status, plasma levels of IL-8 and TNFα were at T=120...

Study of the health effects of bicycling in an urban atmosphere. Final report

Energy Technology Data Exchange (ETDEWEB)

Waldman, M.; Weiss, S.; Articola, W.

1977-10-14

This report analyzes data on the health effects of bicycling in an urban environment through intensive study of ten healthy male subjects bicycling or driving in systematically varied conditions in the streets of Washington, D.C. Evaluation criteria for available technology and instrumentation are included and a methodology is developed for route selection. Specific air pollutants (carbon monoxide, ozone, sulfates, nitrates, and particulates) are measured concurrently with exposure and subsequent changes in health status identified through pulmonary function testing, cardiovascular testing, and blood and symptoms analysis. The report concludes that no major adverse short-term health effects were noted for ten healthy male subjects while bicycling or driving in levels of pollution and thermal stress encountered during the study period. Recommendations for further research are also presented.

Acute growth hormone administration causes exaggerated increases in plasma lactate and glycerol during moderate to high intensity bicycling in trained young men

DEFF Research Database (Denmark)

Lange, K.H.; Larsson, B.; Flyvbjerg, A.

2002-01-01

). In the placebo trial, all subjects completed the exercise protocol without any difficulties. In contrast, two subjects were not able to complete the exercise protocol in the GH trial, and one subject barely managed to complete the protocol. In addition, GH administration resulted in exaggerated increases...... in increased whole body fat oxidation (indirect calorimetry). Plasma glucose was, on average, 9% higher during exercise after GH administration compared with placebo (P ... during 90 min of subsequent bicycling at moderate to high intensity. The exaggerated increase in plasma lactate may be associated with substantially decreased exercise performance....

Test-retest reliabilty of exercise-induced hypoalgesia after aerobic exercise

DEFF Research Database (Denmark)

Vaegter, Henrik Bjarke; Dørge, Daniel Bandholtz; Schmidt, Kristian Sonne

2018-01-01

Objective: Exercise increases pressure pain thresholds (PPTs) in exercising and nonexercising muscles, known as exercise-induced hypoalgesia (EIH). No studies have investigated the test-retest reliability of change in PPTs after aerobic exercise. Primary objectives were to compare the effect...

Myocardial performance and perfusion during exercise in patients with coronary artery disease caused by Kawasaki disease

International Nuclear Information System (INIS)

Paridon, S.M.; Ross, R.D.; Kuhns, L.R.; Pinsky, W.W.

1990-01-01

For a study of the natural history of coronary artery lesions after Kawasaki disease and their effect on myocardial blood flow reserve with exercise, five such patients underwent exercise testing on a bicycle. Oxygen consumption, carbon dioxide production, minute ventilation, and electrocardiograms were monitored continuously. Thallium-201 scintigraphy was performed for all patients. One patient stopped exercise before exhaustion of cardiovascular reserve but had no evidence of myocardial perfusion abnormalities. Four patients terminated exercise because of exhaustion of cardiovascular reserve; one had normal cardiovascular reserve and thallium scintiscans, but the remaining patients had diminished cardiovascular reserve. Thallium scintigrams showed myocardial ischemia in two and infarction in one. No patient had exercise-induced electrocardiographic changes. These results indicate that patients with residual coronary artery lesions after Kawasaki disease frequently have reduced cardiovascular reserve during exercise. The addition of thallium scintigraphy and metabolic measurements to exercise testing improved the detection of exercise-induced abnormalities of myocardial perfusion

Bicycle Crashes

Data.gov (United States)

Town of Chapel Hill, North Carolina — This data set maps the locations of crashes involving bicyclists in the Chapel Hill Region of North Carolina.The data comes from police-reported bicycle-motor...

EFFECT 0F ISOTONIC AND ISOMETRIC EXERCISES ON INTRA OCULAR PRESSURE

Directory of Open Access Journals (Sweden)

Rajendra

2015-10-01

Full Text Available BACKGROUND: Intra O cular Pressure (IOP changes following dynamic (Isotonic or Isokinetic and static (Isometric exercise. AIM: To study the effect of dynamic and static exercises on IOP and blood pressure in the same subject following each type of exercise and to correlate the changes in BP to the changes in the IOP. MATERIALS AND METHODS: The study group consisted of 55 volunteers, visually normal as subjects, 30 boys and 25 girls in the age group of 18 to 20 years. Independent measurements of the IOP of each eye were obtained and BP was also measured in the resting state. Keelar Pulsair air i mpulse tonometer was used in all the subjects for IOP measurement. IOP was measured in the department of Ophthalmology, Teaching Hospital between 08AM to 10 AM on two consecutive mornings in a randomized manner. The subject undertook static exercise using the hand grip dynamometer and towards the end of the test, IOP and BP were measured. The next morning, resting IOP and the BP were measured and the subject undertook the dynamic exercise using the bicycle ergometer and the IOP’s and the BP were measured at the end of the test. STATISTICAL ANALYSIS : were done using Paired ‘t’ test. RESULTS: IOP decreased by 2.58±0.16 mmHg(R eye & 2.64±0.09 mmHg (L eye during exercise using Hand grip dynamometer and the systolic and diastolic blood pressures increased by 14 .73±0.87 & 12.98±1.01 mmHg respectively. The changes were statistically significant (P<0.001. IOP decreased by 2.55±0.07 mmHg(R eye & 2.49±0.1 mmHg(Leye following exercise using bicycle ergometer and the systolic increased by 15.73±1.71 mmHg and the dia stolic decreased by 10.83±2.46 mmHg. The changes were statistically significant (P<0.001. There was no correlation between the changes in BP to the changes in IOP. CONCLUSION: IOP decreased in both static and dynamic exercises. There was no correlation between the changes in BP to the changes in IOP

Effects of an outdoor bicycle-based intervention in healthy rural Indian men with normal and low birth weight

DEFF Research Database (Denmark)

Madsen, C; Mogensen, P; Thomas, N

2015-01-01

Physical inactivity and low birth weight (LBW) may lead to an increased risk for developing type 2 diabetes. The extent to which LBW individuals may benefit from physical exercise training when compared with those with normal birth weight (NBW) controls is uncertain. We assessed the impact...... of an outdoor exercise intervention on body composition, insulin secretion and action in young men born with LBW and NBW in rural India. A total of 61 LBW and 56 NBW healthy young men were recruited into the study. The individuals were instructed to perform outdoor bicycle exercise training for 45 min every day...... with LBW in rural India benefit metabolically from exercise training to an extent comparable with NBW controls....

Children-Adult Comparisons of VO2 and HR Kinetics during Submaximum Exercise.

Science.gov (United States)

Sady, Stanley P.; And Others

1983-01-01

Oxygen uptake and heart rate kinetics for submaximum exercise (bicycle riding) were compared in prepubescent boys and adult men. Resulting data suggest that children and adults do not differ significantly in cardiorespiratory adjustments during low-intensity exercise. (Authors/PP)

Continuous variable transmission and regenerative braking devices in bicycles utilizing magnetorheological fluids

Science.gov (United States)

Cheung, Wai Ming; Liao, Wei-Hsin

2013-04-01

The use of magnetorheological (MR) fluids in vehicles has been gaining popular recently due to its controllable nature, which gives automotive designers more dimensions of freedom in functional designs. However, not much attention has been paid to apply it to bicycles. This paper is aimed to study the feasibility of applying MR fluids in different dynamic parts of a bicycle such as the transmission and braking systems. MR continuous variable transmission (CVT) and power generator assisted in braking systems were designed and analyzed. Both prototypes were fabricated and tested to evaluate their performances. Experimental results showed that the proposed designs are promising to be used in bicycles.

Low-stress bicycling and network connectivity : [research brief].

Science.gov (United States)

2012-05-01

In one sense, a citys or regions bicycling network includes all of its roads and paths on which bicycling is permitted. However, some streets provide such a poor level of safety and comfort for bicycling that the majority of the population cons...

Safety impacts of bicycle infrastructure: A critical review.

Science.gov (United States)

DiGioia, Jonathan; Watkins, Kari Edison; Xu, Yanzhi; Rodgers, Michael; Guensler, Randall

2017-06-01

This paper takes a critical look at the present state of bicycle infrastructure treatment safety research, highlighting data needs. Safety literature relating to 22 bicycle treatments is examined, including findings, study methodologies, and data sources used in the studies. Some preliminary conclusions related to research efficacy are drawn from the available data and findings in the research. While the current body of bicycle safety literature points toward some defensible conclusions regarding the safety and effectiveness of certain bicycle treatments, such as bike lanes and removal of on-street parking, the vast majority treatments are still in need of rigorous research. Fundamental questions arise regarding appropriate exposure measures, crash measures, and crash data sources. This research will aid transportation departments with regard to decisions about bicycle infrastructure and guide future research efforts toward understanding safety impacts of bicycle infrastructure. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.

The Effect of Sharrows, Painted Bicycle Lanes and Physically Protected Paths on the Severity of Bicycle Injuries Caused by Motor Vehicles.

Science.gov (United States)

Wall, Stephen P; Lee, David C; Frangos, Spiros G; Sethi, Monica; Heyer, Jessica H; Ayoung-Chee, Patricia; DiMaggio, Charles J

2016-01-01

We conducted individual and ecologic analyses of prospectively collected data from 839 injured bicyclists who collided with motorized vehicles and presented to Bellevue Hospital, an urban Level-1 trauma center in New York City, from December 2008 to August 2014. Variables included demographics, scene information, rider behaviors, bicycle route availability, and whether the collision occurred before the road segment was converted to a bicycle route. We used negative binomial modeling to assess the risk of injury occurrence following bicycle path or lane implementation. We dichotomized U.S. National Trauma Data Bank Injury Severity Scores (ISS) into none/mild (0-8) versus moderate, severe, or critical (>8) and used adjusted multivariable logistic regression to model the association of ISS with collision proximity to sharrows (i.e., bicycle lanes designated for sharing with cars), painted bicycle lanes, or physically protected paths. Negative binomial modeling of monthly counts, while adjusting for pedestrian activity, revealed that physically protected paths were associated with 23% fewer injuries. Painted bicycle lanes reduced injury risk by nearly 90% (IDR 0.09, 95% CI 0.02-0.33). Holding all else equal, compared to no bicycle route, a bicycle injury nearby sharrows was nearly twice as likely to be moderate, severe, or critical (adjusted odds ratio 1.94; 95% confidence interval (CI) 0.91-4.15). Painted bicycle lanes and physically protected paths were 1.52 (95% CI 0.85-2.71) and 1.66 (95% CI 0.85-3.22) times as likely to be associated with more than mild injury respectively.

The Effect of Sharrows, Painted Bicycle Lanes and Physically Protected Paths on the Severity of Bicycle Injuries Caused by Motor Vehicles

Directory of Open Access Journals (Sweden)

Stephen P. Wall

2016-12-01

Full Text Available We conducted individual and ecologic analyses of prospectively collected data from 839 injured bicyclists who collided with motorized vehicles and presented to Bellevue Hospital, an urban Level-1 trauma center in New York City, from December 2008 to August 2014. Variables included demographics, scene information, rider behaviors, bicycle route availability, and whether the collision occurred before the road segment was converted to a bicycle route. We used negative binomial modeling to assess the risk of injury occurrence following bicycle path or lane implementation. We dichotomized U.S. National Trauma Data Bank Injury Severity Scores (ISS into none/mild (0–8 versus moderate, severe, or critical (>8 and used adjusted multivariable logistic regression to model the association of ISS with collision proximity to sharrows (i.e., bicycle lanes designated for sharing with cars, painted bicycle lanes, or physically protected paths. Negative binomial modeling of monthly counts, while adjusting for pedestrian activity, revealed that physically protected paths were associated with 23% fewer injuries. Painted bicycle lanes reduced injury risk by nearly 90% (IDR 0.09, 95% CI 0.02–0.33. Holding all else equal, compared to no bicycle route, a bicycle injury nearby sharrows was nearly twice as likely to be moderate, severe, or critical (adjusted odds ratio 1.94; 95% confidence interval (CI 0.91–4.15. Painted bicycle lanes and physically protected paths were 1.52 (95% CI 0.85–2.71 and 1.66 (95% CI 0.85–3.22 times as likely to be associated with more than mild injury respectively.

Cardiopulmonary Exercise Testing in Pediatrics

NARCIS (Netherlands)

Takken, Tim; Bongers, Bart C; van Brussel, Marco; Haapala, Eero A; Hulzebos, Erik Hj

2017-01-01

Aerobic fitness is an important determinant of overall health. Higher aerobic fitness has been associated with many health benefits. Because myocardial ischemia is rare in children, indications for exercise testing differ in children compared to adults. Pediatric exercise testing is imperative to

Examining physiotherapist use of structured aerobic exercise testing to decrease barriers to aerobic exercise.

Science.gov (United States)

Foster B Sc, Evan; Fraser, Julia E; Inness PhD, Elizabeth L; Munce, Sarah; Biasin, Louis; Poon, Vivien; Bayley, Mark

2018-04-03

To determine the frequency of physiotherapist-administered aerobic exercise testing/training, the proportion of physiotherapists who administer this testing/training, and the barriers that currently exist across different practice environments. A secondary objective is to identify the learning needs of physiotherapists for the development of an education curriculum in aerobic exercise testing and training with electrocardiograph (ECG) administration and interpretation. National, cross-sectional survey. Registered physiotherapists practicing in Canada. Out of 137 participants, most (75%) physiotherapists prescribed aerobic exercise on a regular basis (weekly); however, 65% had never conducted an aerobic exercise test. There were no significant differences in frequency of aerobic exercise testing across different practice environments or across years of physiotherapy experience. Physiotherapists perceived the main barriers to aerobic exercise testing as being a lack of equipment/space (78%), time (65%), and knowledge (56%). Although most (82%) were uncomfortable administering 12-lead ECG-monitored aerobic exercise tests, 60% stated they would be interested in learning more about ECG interpretation. This study found that physiotherapists are regularly implementing aerobic exercise. This exercise was infrequently guided by formal aerobic exercise testing, which could increase access to safe and effective exercise within the optimal aerobic training zone. As well, this could facilitate training in patients with cardiovascular diagnoses that require additional testing for medical clearance. Increased ECG training and access to equipment for physiotherapists may augment pre-screening aerobic exercise testing. This training should include learning the key arrhythmias for aerobic exercise test termination as defined by the American College of Sports Medicine.

Biking for Health: Results of a Pilot Randomized Controlled Trial Examining the Impact of a Bicycling Intervention on Lower-Income Adults.

Science.gov (United States)

Bernstein, Rebecca; Schneider, Robert; Welch, Whitney; Dressel, Anne; DeNomie, Melissa; Kusch, Jennifer; Sosa, Mirtha

2017-08-01

This pilot study tested the efficacy of a bicycling intervention targeting inactive, low-income, overweight adults on reducing perceived barriers to bicycling, increasing physical activity, and improving health. A nonblinded 2-site randomized controlled trial was conducted in Milwaukee, Wisconsin, in summer 2015. Participants included members from 1 largely Latino community and a second primarily African American neighborhood. A certified bicycling instructor led a 12-week bicycling intervention. Outcome measures including biking-related attitudes, self-reported physical activity, fitness as measured by the 6-minute step test, and biometric data were collected at baseline, 12 weeks, and 20 weeks. Thirty-eight participants completed the study. Barriers to bicycling declined significantly among intervention group participants at 12 weeks with some declines persisting to 20 weeks. Bicycling for leisure or non work transportation increased significantly more in the intervention than control group from baseline to 12 weeks but this difference attenuated by 20 weeks. Both groups increased their fitness between baseline and 12 weeks, with a trend towards greater gains in the bicycling intervention group. No significant change in biometric measurements was seen at either 12 weeks or 20 weeks. Despite the small study size, this bicycling intervention decreased perceived barriers to bicycling and increased bicycling activity in low-income minority participants. These findings support a larger-scale study to measure fitness and health changes from bicycling interventions.

Predicting Free Flow Speed and Crash Risk of Bicycle Traffic Flow Using Artificial Neural Network Models

Directory of Open Access Journals (Sweden)

Cheng Xu

2015-01-01

Full Text Available Free flow speed is a fundamental measure of traffic performance and has been found to affect the severity of crash risk. However, the previous studies lack analysis and modelling of impact factors on bicycles’ free flow speed. The main focus of this study is to develop multilayer back propagation artificial neural network (BPANN models for the prediction of free flow speed and crash risk on the separated bicycle path. Four different models with considering different combinations of input variables (e.g., path width, traffic condition, bicycle type, and cyclists’ characteristics were developed. 459 field data samples were collected from eleven bicycle paths in Hangzhou, China, and 70% of total samples were used for training, 15% for validation, and 15% for testing. The results show that considering the input variables of bicycle types and characteristics of cyclists will effectively improve the accuracy of the prediction models. Meanwhile, the parameters of bicycle types have more significant effect on predicting free flow speed of bicycle compared to those of cyclists’ characteristics. The findings could contribute for evaluation, planning, and management of bicycle safety.

Testing for Exercise-Induced Bronchoconstriction

DEFF Research Database (Denmark)

Brannan, John D; Porsbjerg, Celeste

2018-01-01

of an individual who may be at risk during a recreational sporting activity or when exercising as an occupational duty. EIB can be identified with laboratory exercise testing or surrogate tests for EIB. These include eucapnic voluntary hyperpnea and osmotic stimuli (eg, inhaled mannitol) and offer improved...

Electric bicycles in The Netherlands: Current developments and future possibilities

NARCIS (Netherlands)

Rooijen, T. van

2010-01-01

Developments with electric bicycles in the Netherlands are progressing rapidly. The number of electric bicycles sold is rises every year. Cycling is a very popular mode of transport in The Netherlands. In 2008 more than one million bicycles were sold. At the moment one out of ten bicycles sold is

Walking, bicycling, and sports in postmenopausal breast cancer survivors--results from a German patient cohort study.

Science.gov (United States)

Bock, Christina; Schmidt, Martina E; Vrieling, Alina; Chang-Claude, Jenny; Steindorf, Karen

2013-06-01

Physical activity (PA) is increasingly discussed as a means to achieve both physical and psychological benefits for breast cancer patients and survivors. However, little is known about activity-specific PA behavior following diagnosis. Our objectives were to describe sports and active transportation in the course of breast cancer and to identify factors associated with these activities. We used data from a German cohort study including 1067 postmenopausal breast cancer survivors aged 50-75 years. Data were collected about walking and bicycling for transportation purposes and sports before diagnosis, during therapy, and 1 year after surgery. Associations between these activities and clinical, behavioral, and social characteristics were analyzed with logistic regression. The proportions of physically active women decreased significantly during therapy compared with before diagnosis (walking: 75.1% vs. 89.7%; bicycling: 19.3% vs. 56.5%; sports: 14.8% vs. 64.5%; all p sport. Chemotherapy/radiotherapy was negatively associated with sports (odds ratio [OR]: 0.35 [0.17-0.73]) but positively associated with walking during therapy (OR: 2.08 [1.04-4.15]). Although sociodemographic factors showed weak associations with PA, participation in rehabilitation increased the likelihood for bicycling (OR: 1.48 [1.06-2.09]) and sports (OR: 1.88 [1.38-2.58]) 1 year after surgery. The majority of women stopped exercising and bicycling during breast cancer therapy. Interventions promoting in particular moderate activities after breast cancer diagnosis are required for this population. Increasing participation in rehabilitation might help to increase the proportion of women who bicycle and engage in sports after breast cancer diagnosis. Copyright © 2012 John Wiley & Sons, Ltd.

Safety effects of permanent running lights for bicycles

DEFF Research Database (Denmark)

Madsen, Jens Chr. Overgaard; Andersen, T.; Lahrmann, Harry

2013-01-01

, including all recorded bicycle accidents with personal injury to the participating cyclist, is 19% lower for cyclists with permanent running lights mounted; indicating that the permanent bicycle running light significantly improves traffic safety for cyclists. The study shows that use of permanent bicycle......Making the use of daytime running lights mandatory for motor vehicles is generally documented to have had a positive impact upon traffic safety. Improving traffic safety for bicyclists is a focal point in the road traffic safety work in Denmark. In 2004 and 2005 a controlled experiment including...... 3845 cyclists was carried out in Odense, Denmark in order to examine, if permanent running lights mounted to bicycles would improve traffic safety for cyclists. The permanent running lights were mounted to 1845 bicycles and the accident rate was recorded through 12 months for this treatment group...

[Associations of the work duration, sleep duration and number of holidays with an exaggerated blood pressure response during an exercise stress test among workers].

Science.gov (United States)

Michishita, Ryoma; Ohta, Masanori; Ikeda, Masaharu; Jiang, Ying; Yamato, Hiroshi

2016-01-01

It has been reported that an exaggerated systolic blood pressure (ESBP) response during exercise, even if resting blood pressure is normal, is associated with an increased risk of future hypertension and cardiovascular disease (CVD). This study was designed to investigate the relationships of work duration, sleep duration and number of holidays with blood pressure response during an exercise stress test among normotensive workers. The subjects were 362 normotensive workers (79 males and 283 females; age, 49.1 years). A multi-stage graded submaximal exercise stress test was performed on each subject using an electric bicycle ergometer. The workload was increased every 3 minutes, and blood pressure was measured at rest and during the last 1 minute of each stage. In this study, an ESBP response during exercise was defined according to the criteria of the Framingham Study (peak systolic blood pressure ≥210 mmHg in males, or ≥190 mmHg in females). Working environments, work duration, sleep duration, number of holidays, and physical activity during commuting and work, and leisure time exercise duration were evaluated using a questionnaire. An ESBP response during exercise was observed in 94 (26.0%) workers. The adjusted odds ratio for the prevalence of an ESBP response during exercise was found to be significantly higher with an increase in work duration, decreases in sleep duration and number of holidays (pwork duration with lowest sleep duration and number of holidays groups had significantly higher adjusted odds ratio for the prevalence of an ESBP response during exercise than the lowest work duration with highest sleep duration and number of holidays groups (pwork duration, short sleep duration and small number of holidays.

The effect of a yellow bicycle jacket on cyclist accidents

DEFF Research Database (Denmark)

Lahrmann, Harry; Madsen, Tanja Kidholm Osmann; Olesen, Anne Vingaard

2018-01-01

Highlights •A randomised controlled trial with 6793 cyclists shows a reduced accident risk due to a yellow bicycle jacket. •The test group had 47% fewer multiparty accidents with personal injury. •The test group had 55% fewer multiparty accidents against motorised vehicles....

Diagnostic value of ST-segment deviations during cardiac exercise stress testing: Systematic comparison of different ECG leads and time-points.

Science.gov (United States)

Puelacher, Christian; Wagener, Max; Abächerli, Roger; Honegger, Ursina; Lhasam, Nundsin; Schaerli, Nicolas; Prêtre, Gil; Strebel, Ivo; Twerenbold, Raphael; Boeddinghaus, Jasper; Nestelberger, Thomas; Rubini Giménez, Maria; Hillinger, Petra; Wildi, Karin; Sabti, Zaid; Badertscher, Patrick; Cupa, Janosch; Kozhuharov, Nikola; du Fay de Lavallaz, Jeanne; Freese, Michael; Roux, Isabelle; Lohrmann, Jens; Leber, Remo; Osswald, Stefan; Wild, Damian; Zellweger, Michael J; Mueller, Christian; Reichlin, Tobias

2017-07-01

Exercise ECG stress testing is the most widely available method for evaluation of patients with suspected myocardial ischemia. Its major limitation is the relatively poor accuracy of ST-segment changes regarding ischemia detection. Little is known about the optimal method to assess ST-deviations. A total of 1558 consecutive patients undergoing bicycle exercise stress myocardial perfusion imaging (MPI) were enrolled. Presence of inducible myocardial ischemia was adjudicated using MPI results. The diagnostic value of ST-deviations for detection of exercise-induced myocardial ischemia was systematically analyzed 1) for each individual lead, 2) at three different intervals after the J-point (J+40ms, J+60ms, J+80ms), and 3) at different time points during the test (baseline, maximal workload, 2min into recovery). Exercise-induced ischemia was detected in 481 (31%) patients. The diagnostic accuracy of ST-deviations was highest at +80ms after the J-point, and at 2min into recovery. At this point, ST-amplitude showed an AUC of 0.63 (95% CI 0.59-0.66) for the best-performing lead I. The combination of ST-amplitude and ST-slope in lead I did not increase the AUC. Lead I reached a sensitivity of 37% and a specificity of 83%, with similar sensitivity to manual ECG analysis (34%, p=0.31) but lower specificity (90%, pST-deviations is highest when evaluated at +80ms after the J-point, and at 2min into recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

Anaerobic Degradation of Bicyclic Monoterpenes in Castellaniella defragrans

Directory of Open Access Journals (Sweden)

Edinson Puentes-Cala

2018-02-01

Full Text Available The microbial degradation pathways of bicyclic monoterpenes contain unknown enzymes for carbon–carbon cleavages. Such enzymes may also be present in the betaproteobacterium Castellaniella defragrans, a model organism to study the anaerobic monoterpene degradation. In this study, a deletion mutant strain missing the first enzyme of the monocyclic monoterpene pathway transformed cometabolically the bicyclics sabinene, 3-carene and α-pinene into several monocyclic monoterpenes and traces of cyclic monoterpene alcohols. Proteomes of cells grown on bicyclic monoterpenes resembled the proteomes of cells grown on monocyclic monoterpenes. Many transposon mutants unable to grow on bicyclic monoterpenes contained inactivated genes of the monocyclic monoterpene pathway. These observations suggest that the monocyclic degradation pathway is used to metabolize bicyclic monoterpenes. The initial step in the degradation is a decyclization (ring-opening reaction yielding monocyclic monoterpenes, which can be considered as a reverse reaction of the olefin cyclization of polyenes.

An international review of the frequency of single-bicycle crashes (SBCs) and their relation to bicycle modal share

DEFF Research Database (Denmark)

Schepers, Paul; Agerholm, Niels; Amoros, Emmanuelle

2015-01-01

of SBC casualties among the total number of road crash casualties increases proportionally less than the increase in bicycle modal share. Conclusions While most fatal injuries among cyclists are due to motor vehicle–bicycle crashes, most hospital admissions and emergency department attendances result...

Fatal Cervical Spine Injury Following a Bicycle Crash

Directory of Open Access Journals (Sweden)

Uhrenholt Lars

2017-06-01

Full Text Available Spinal injury following direct loading of the head and neck is a rare sequel of bicycle crashes. Fatal head injuries following bicycle crashes have been described in great detail and safety measures such as bicycle helmets have been developed accordingly. Less frequently, however, potentially severe cervical spine injuries have been described. We present the case of a middle-aged female who sustained an ultimately fatal cervical spine injury following a collision with a car whilst biking wearing a helmet. We discuss the literature regarding the protective effects of bicycle helmets, the relevance to cervical spine injury and legislation on mandatory use of helmets for injury prevention.

Statewide analysis of bicycle crashes : [project summary].

Science.gov (United States)

2017-06-01

An extensive literature review was conducted to locate existing studies in four areas: (1) risk factors that affect the frequency and severity of bicycle crashes; (2) bicycle crash causes, patterns, and contributing factors; (3) network screening met...

Likelihood of myocardial infarction during stroke rehabilitation preceded by cardiovascular screening and an exercise tolerance test: the Locomotor Experience Applied Post-Stroke (LEAPS) trial.

Science.gov (United States)

Nadeau, Stephen E; Rose, Dorian Kay; Dobkin, Bruce; Wu, Samuel S; Dai, Yufeng E; Schofield, Richard; Duncan, Pamela W

2014-12-01

Coronary artery disease is highly prevalent in patients with stroke, but because revascularization does not improve major clinical outcomes in patients with stable coronary artery disease relative to intensive medical therapy, routine evaluation for this disease is not warranted in stroke patients. However, it might be warranted in patients destined to undergo vigorous physical therapy. The Locomotor Experience Applied Post-Stroke study, a randomized controlled trial of 408 participants that tested the relative efficacy of two rehabilitation techniques on functional walking level, provided the opportunity to address this question. The study aims to test the efficacy of screening for cardiovascular disease and an exercise tolerance test in assuring safety among patients undergoing vigorous rehabilitation for gait impairment. All participants were screened for serious cardiovascular and pulmonary conditions. At six-weeks poststroke, they also completed a cardiovascular screening inventory and underwent an exercise tolerance test involving bicycle ergometry. Participants received 36, 90-min sessions of a prescribed physical therapy (three per week), initiated at either two-months or six-months poststroke. Twenty-nine participants were excluded on the basis of the cardiac screening questionnaire, and 15 failed the exercise tolerance test for cardiovascular reasons. No participant experienced a cardiac event during a treatment session. Two participants experienced myocardial infarctions, but continued in the trial. In three additional participants, myocardial infarctions caused or contributed to death. The combination of a negative cardiac screen and the absence of exercise tolerance test failure appeared to have a high negative predictive value for cardiac events during treatment, despite the likelihood of a high prevalence of coronary artery disease in our population. © 2014 World Stroke Organization.

The environmental benefits of bicycling and walking.

Science.gov (United States)

1993-01-01

Bicycling and walking are the two major non-fuel-consuming, non-polluting : forms of transportation in the United States. Millions of Americans ride : bicycles and/or walk for a wide variety of purposes --- commuting to work, as : part of their job, ...

Effect of exercise intensity on lipid profile in sedentary obese adults.

Science.gov (United States)

Kannan, Umamaheswari; Vasudevan, Kavita; Balasubramaniam, Kavita; Yerrabelli, Dhanalakshmi; Shanmugavel, Karthik; John, Nitin Ashok

2014-07-01

Exercise is a lifestyle change that has been recommended for lowering atherogenic index in adults. The intensity and duration of exercise to bring about a change in the lipid parameters are yet to be determined. Previous studies examining the effects of exercise intensity on lipid and lipoprotein levels have reported conflicting findings. Thus we aimed at determining the changes in lipid profile in sedentary obese adults influenced by different intensity of exercise. Study included 51 obese adults with sedentary lifestyle. Participants performed exercise of moderate intensity (n=22) and high intermittent intensity (n=29) for a duration of 40min/day for 5 days/week and 20 min/day for 3 days/week respectively on bicycle ergometer for a period of 15 weeks. Pretesting and post testing included measurement of height, weight, blood pressure and lipid profile. RESULTS were analysed using the Paired and Unpaired samples t-test. Postexercise revealed significant reduction in the LDL-C and diastolic blood pressure (plife. High intermittent intensity can be considered for individuals who have time constraints and lead a sedentary life style and moderate intensity exercise advised for individuals who are willing to create time for their health benefits. A programmed protocol of exercise will help in reduction of lipid parameters.

Revitalization of Cycling in a Former Bicycle Kingdom: Beijing

DEFF Research Database (Denmark)

Zhao, Chunli; Carstensen, Trine Agervig; Olafsson, Anton Stahl

This paper scrutinizes and analyses the relevant historical policy documents chronologically - from the 1960s to the present - in order to figure out the potentials of revitalizing the bicycle mode share in Beijing. Firstly, we targeted two top-drawer conflicts of the bicycle use, which are travel......- or commuting distance and motorised vehicle-oriented urban development. Secondly, we analysed how the various related policies resulted in the changing landscape of the bicycle mode share, including increasing in the bicycle mode share, created the conflicts and declined the bicycle mode share. The results...... are revealed by collection and analysis of historical material and interviews with key stakeholders. The historical material is obtained from libraries, online resources, and reports from professionals including urban designers, transportation engineers, research centres and politicians of the Beijing...

Evaluation electric bicycles; Evaluation velos electriques

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-10-01

Leovelo service is the first measure in favor of the bicycle to control the air pollution and to conserve energy. It provides in the city of Clermont-Ferrand (France) a service of bicycle hiring. This document evaluates the project after two years of operating. It provides a technical evaluation (maintenance, equipment, financing) and also the socio-economic impacts. (A.L.B.)

Mountain bicycle frame testing as an example of practical implementation of hybrid simulation using RTFEM

Science.gov (United States)

Mucha, Waldemar; Kuś, Wacław

2018-01-01

The paper presents a practical implementation of hybrid simulation using Real Time Finite Element Method (RTFEM). Hybrid simulation is a technique for investigating dynamic material and structural properties of mechanical systems by performing numerical analysis and experiment at the same time. It applies to mechanical systems with elements too difficult or impossible to model numerically. These elements are tested experimentally, while the rest of the system is simulated numerically. Data between the experiment and numerical simulation are exchanged in real time. Authors use Finite Element Method to perform the numerical simulation. The following paper presents the general algorithm for hybrid simulation using RTFEM and possible improvements of the algorithm for computation time reduction developed by the authors. The paper focuses on practical implementation of presented methods, which involves testing of a mountain bicycle frame, where the shock absorber is tested experimentally while the rest of the frame is simulated numerically.

Finding the Speed of a Bicycle in Circular Motion by Measuring the Lean Angle of the Bicycle

Science.gov (United States)

Ben-Abu, Yuval; Wolfson, Ira; Yizhaq, Hezi

2018-01-01

We suggest an activity for measuring the speed of a bicycle going in circular motion by measuring the bicycle's lean angle. In this activity students will be able to feel the strength that is being activated on their bodies while they are moving in circular motion. They will also understand that it is impossible to ride in a circle without the…

The effect of cannabis on regular cannabis consumers' ability to ride a bicycle.

Science.gov (United States)

Hartung, Benno; Schwender, Holger; Roth, Eckhard H; Hellen, Florence; Mindiashvili, Nona; Rickert, Annette; Ritz-Timme, Stefanie; Grieser, Almut; Monticelli, Fabio; Daldrup, Thomas

2016-05-01

To assess the effects of cannabis on the ability required to ride a bicycle, repetitive practical cycling tests and medical examinations were carried out before and after inhalative consumption of cannabis. A maximum of three joints with body weight-adapted THC content (300 μg THC per kg body weight) could be consumed by each test subject. Fourteen regular cannabis-consuming test subjects were studied (12 males, 2 females). In summary, only a few driving faults were observed even under the influence of very high THC concentrations. A defined THC concentration that leads to an inability to ride a bicycle cannot be presented. The test subjects showed only slight distinctive features that can be documented using a medical test routinely run for persons under suspicion of driving under the influence of alcohol or drugs.

Cyclists' attitudes toward policies encouraging bicycle travel: findings from the Taupo Bicycle Study in New Zealand.

Science.gov (United States)

Tin Tin, Sandar; Woodward, Alistair; Thornley, Simon; Langley, John; Rodgers, Anthony; Ameratunga, Shanthi

2010-03-01

Utility cycling provides substantial health, environmental and economic benefits. Despite a favourable trend in leisure-time cycling, cycling is infrequently used for everyday travel needs in New Zealand. This study investigated cyclists' attitudes toward environmental and policy measures that would encourage them to cycle more, particularly for a trip to work. A cross-sectional analysis was undertaken using baseline data obtained from the Taupo Bicycle Study, a web-based longitudinal study. The study population comprised 2469 cyclists, aged 16 years or over, who had enrolled in the 2006 Wattyl Lake Taupo Cycle Challenge. The majority (88%) reported the provision of bicycle lanes as an important factor that would encourage them to cycle more often, followed by bicycle paths (76%), better bicycle security (64%), reduced motor vehicle speed (55%) and bike friendly public transport (38%). Of those who reported travelling to work at least once a week (N = 2223), varying proportions reported shower facilities at work (61%), fewer difficult intersections (43%), rising fuel costs (41%), fewer car parks (27%), bike designed to commute (26%) and rising cost of car parking (25%) as important factors that would encourage them to cycle to work more often. There were important differences in these perceived influences defined by the participants' socio-demographic characteristics and current cycling habits.

BICYCLE HELMET DESIGN AND THE VIRTUAL VALIDATION OF THE IMPACT, AERODYNAMICS AND PRODUCTION PROCESS

Directory of Open Access Journals (Sweden)

Bojan Boshevski

2017-12-01

Full Text Available This paper presents the development process of a bicycle helmet through individual research, creation, presentation and analysis of the results of the most important product development stages. The quality of the development and manufacturing process of the protective equipment for extreme sports is an imperative for a successful product and its flawless function. The design of the bicycle helmet is made following the rules of the design in order to create a well-founded and functional product. After creating design sketches, a virtual prototype was developed in "SolidWorks" using the required ergonomic dimensions. 3D printed model of the human head with adapted ergonomic dimensions and the designed bicycle helmet was developed in order to verify the applied ergonomic measures. The virtual model will be used as an input in the finite element analysis of the helmet impact test based on the EN1078 standard and the aerodynamic simulations executed in "SolidWorks Simulation and Flow Simulation", for verification of the impact and aerodynamic properties. Virtual testing of aerodynamic features and the ability of the bicycle helmet to allow ventilation of the user's head indicate that the helmet performs its function in the desired way. Also, the virtual prototype will be used for the production process simulation in "SolidWorks Plastics" in order to analyze the production of the bicycle helmet. The polycarbonate helmet outer shell is subject to a number of simulations for the sake of analyzing the production process in order to obtain the desired characteristics of the polycarbonate outer shell and to avoid the disadvantages that occur in the manufacturing process. The main goal of this paper is to develop a safety bicycle helmet with improved ergonomic, validation of impact, aerodynamic characteristics and production process in order to produce a high quality product for mass use.

Injury rates from walking, gardening, weightlifting, outdoor bicycling, and aerobics.

Science.gov (United States)

Powell, K E; Heath, G W; Kresnow, M J; Sacks, J J; Branche, C M

1998-08-01

The objective of this survey was to estimate the frequency of injuries associated with five commonly performed moderately intense activities: walking for exercise, gardening and yard work, weightlifting, aerobic dance, and outdoor bicycling. National estimates were derived from weighted responses of over 5,000 individuals contacted between April 28 and September 18, 1994, via random-digit dialing of U.S. residential telephone numbers. Self-reported participation in these five activities in the late spring and summer of 1994 was common, ranging from an estimated 14.5 +/- 1.2% of the population for aerobics (nearly 30 million people) to 73.0 +/- 1.5% for walking (about 138 million people). Among participants, the activity-specific 30-d prevalence of injury ranged from 0.9 +- 0.5% for outdoor bicycle riding to 2.4 +- 1.3% for weightlifting. The estimated number in the 30 d of people injured in the 30 d before their interview ranged from 330,000 for outdoor bicycle riding to 2.1 million for gardening or yard work. Incidence rates for injury causing reduced participation in activity were 1.1 +/- 0.5x100 participantsx30 d for walking, 1.1 +/- 0.4 for gardening, and 3.3 +/- 1.9 for weightlifting. During walking and gardening, men and women were equally likely to be injured, but younger people (18-44 yr) were more likely to be injured than older people (45 + yr). Injury rates were low, yet large numbers of people were injured because participation rates were high. Most injuries were minor, but injuries may reduce participation in these otherwise beneficial activities. Additional studies to confirm the magnitude of the problem, to identify modifiable risk factors, and to recommend methods to reduce the frequency of such injuries are needed.

Do Online Bicycle Routing Portals Adequately Address Prevalent Safety Concerns?

Directory of Open Access Journals (Sweden)

Martin Loidl

2018-03-01

Full Text Available Safety concerns are among the most prevalent deterrents for bicycling. The provision of adequate bicycling infrastructure is considered as one of the most efficient means to increase cycling safety. However, limited public funding does not always allow agencies to implement cycling infrastructure improvements at the desirable level. Thus, bicycle trip planners can at least partly alleviate the lack of adequate infrastructure by recommending optimal routes in terms of safety. The presented study provides a systematic review of 35 bicycle routing applications and analyses to which degree they promote safe bicycling. The results show that most trip planners lack corresponding routing options and therefore do not sufficiently address safety concerns of bicyclists. Based on these findings, we developed recommendations on how to better address bicycling safety in routing portals. We suggest employing current communication technology and analysis to consider safety concerns more explicitly.

Influence of the cognitive workload on bicycle safety at four-legged intersections

DEFF Research Database (Denmark)

Kveladze, Irma; Agerholm, Niels

2018-01-01

is the influence of workload capacity on bicyclists spatial behaviour in a natural environment of four-legged intersections. Method: Due to the traffic safety of test participants, the study is divided in two phases. In the first phase, the actual physical environment of the four-legged intersection and bicyclists......-legged intersection. The eye tracking glasses will be used to make video and audio recording of visible field of where or how long bicyclists are allocating their visual attention while riding a bicycle and facing obstacles when crossing the four-legged intersection. On the second phase, a bicycle riding simulator...... riding task. This will allow to understand the allocation of bicyclists attention between primary and secondary tasks, to reveal the limit of the information processing capacity during biking. Results expected: Two experimental results will be incorporated to gain in-depth knowledge on bicycle accidents...

SOFIE, a bicycle that supports older cyclists?

NARCIS (Netherlands)

Dubbeldam, R.; Baten, C.; Buurke, J. H.; Rietman, J. S.

2017-01-01

Older cyclists remain at high risk of sustaining an injury after a fall with their bicycle. A growing awareness for the need and possibilities to support safety of older cyclists has been leading to bicycle design ideas. However, the effectiveness and acceptance of such designs has not been studied

Exercise performance, red blood cell deformability, and lipid peroxidation: effects of fish oil and vitamin E

NARCIS (Netherlands)

Oostenbrug, G. S.; Mensink, R. P.; Hardeman, M. R.; de Vries, T.; Brouns, F.; Hornstra, G.

1997-01-01

Previous studies have indicated that fish oil supplementation increases red blood cell (RBC) deformability, which may improve exercise performance. Exercise alone, or in combination with an increase in fatty acid unsaturation, however, may enhance lipid peroxidation. Effects of a bicycle time trial

Malonyl-CoA and carnitine in regulation of fat oxidation in human skeletal muscle during exercise

DEFF Research Database (Denmark)

Roepstorff, Carsten; Halberg, Nils; Hillig, Thore

2005-01-01

Intracellular mechanisms regulating fat oxidation were investigated in human skeletal muscle during exercise. Eight young, healthy, moderately trained men performed bicycle exercise (60 min, 65% peak O2 consumption) on two occasions, where they ingested either 1) a high-carbohydrate diet (H-CHO) ...

Incremental value of clinical assessment, supine exercise electrocardiography, and biplane exercise radionuclide ventriculography in the prediction of coronary artery disease in men with chest pain

International Nuclear Information System (INIS)

Currie, P.J.; Kelly, M.J.; Harper, R.W.; Federman, J.; Kalff, V.; Anderson, S.T.; Pitt, A.

1983-01-01

The incremental value of clinical assessment, exercise electrocardiography (ECG) and biplane radionuclide ventriculography (RVG) in the prediction of coronary artery disease (CAD) was assessed in 105 men without myocardial infarction who were undergoing coronary angiography for investigation of chest pain. Independent clinical assessment of chest pain was made prospectively by 2 physicians. Graded supine bicycle exercise testing was symptom-limited. Right anterior oblique ECG-gated first-pass RVG and left anterior oblique ECG-gated equilibrium RVG were performed at rest and exercise. Regional wall motion abnormalities were defined by agreement of 2 of 3 blinded observers. A combined strongly positive exercise ECG response was defined as greater than or equal to 2 mm ST depression or 1.0 to 1.9 mm ST depression with exercise-induced chest pain. A multivariate logistic regression model for the preexercise prediction of CAD was derived from the clinical data and selected 2 variables: chest pain class and cholesterol level. A second model assessed the incremental value of the exercise test in prediction of CAD and found 2 exercise variables that improved prediction: RVG wall motion abnormalities, and a combined strongly positive ECG response. Applying the derived predictive models, 37 of the 58 patients (64%) with preexercise probabilities of 10 to 90% crossed either below the 10% probability threshold or above the 90% threshold and 28 (48%) also moved across the 5 and 95% thresholds. Supine exercise testing with ECG and biplane RVG together, but neither test alone, effectively adds to clinical prediction of CAD. It is most useful in men with atypical chest pain and when the ECG and RVG results are concordant

Bicyclic peptide inhibitor of urokinase-type plasminogen activator

DEFF Research Database (Denmark)

Roodbeen, Renée; Jensen, Berit Paaske; Jiang, Longguang

2013-01-01

The development of protease inhibitors for pharmacological intervention has taken a new turn with the use of peptide-based inhibitors. Here, we report the rational design of bicyclic peptide inhibitors of the serine protease urokinase-type plasminogen activator (uPA), based on the established...... investigated the solution structures of the bicyclic peptide by NMR spectroscopy to map possible conformations. An X-ray structure of the bicyclic-peptide-uPA complex confirmed an interaction similar to that for the previous upain-1/upain-2-uPA complexes. These physical studies of the peptide...

The relationship between bicycle commuting and perceived stress: a cross-sectional study.

Science.gov (United States)

Avila-Palencia, Ione; de Nazelle, Audrey; Cole-Hunter, Tom; Donaire-Gonzalez, David; Jerrett, Michael; Rodriguez, Daniel A; Nieuwenhuijsen, Mark J

2017-06-23

Active commuting - walking and bicycling for travel to and/or from work or educational addresses - may facilitate daily, routine physical activity. Several studies have investigated the relationship between active commuting and commuting stress; however, there are no studies examining the relationship between solely bicycle commuting and perceived stress, or studies that account for environmental determinants of bicycle commuting and stress. The current study evaluated the relationship between bicycle commuting, among working or studying adults in a dense urban setting, and perceived stress. A cross-sectional study was performed with 788 adults who regularly travelled to work or study locations (excluding those who only commuted on foot) in Barcelona, Spain. Participants responded to a comprehensive telephone survey concerning their travel behaviour from June 2011 through to May 2012. Participants were categorised as either bicycle commuters or non-bicycle commuters, and (based on the Perceived Stress Scale, PSS-4) as either stressed or non-stressed. Multivariate Poisson regression with robust variance models of stress status based on exposures with bicycle commuting were estimated and adjusted for potential confounders. Bicycle commuters had significantly lower risk of being stressed than non-bicycle commuters (Relative Risk; RR (95% CI)=0.73 (0.60 to 0.89), p=0.001). Bicycle commuters who bicycled 4 days per week (RR (95% CI)=0.42 (0.24 to 0.73), p=0.002) and those who bicycled 5 or more days per week (RR (95% CI)=0.57 (0.42 to 0.77), pstressed than those who bicycled less than 4 days. This relationship remained statistically significant after adjusting for individual and environmental confounders and when using different cut-offs of perceived stress. Stress reduction may be an important consequence of routine bicycle use and should be considered by decision makers as another potential benefit of its promotion. © Article author(s) (or their employer

Synthesis and anticonvulsant activity of novel bicyclic acidic amino acids

DEFF Research Database (Denmark)

Conti, Paola; De Amici, Marco; Joppolo Di Ventimiglia, Samuele

2003-01-01

Bicyclic acidic amino acids (+/-)-6 and (+/-)-7, which are conformationally constrained homologues of glutamic acid, were prepared via a strategy based on a 1,3-dipolar cycloaddition. The new amino acids were tested toward ionotropic and metabotropic glutamate receptor subtypes; both of them...

Effects of a Static Bicycling Programme on the Functional Ability of Young People with Cerebral Palsy Who Are Non-Ambulant

Science.gov (United States)

Williams, Heather; Pountney, Teresa

2007-01-01

This study investigated the effects of exercise on the motor function of 11 young people (10 females, one male; age range 11-15y; mean age 12y 7mo [SD 1y 4mo]) with cerebral palsy (CP) who were non-ambulant (Gross Motor Function Classification System Levels IV or V), using an adapted static bicycle. Three participants had dyskinetic quadriplegia,…

Butchers and Bicycles

DEFF Research Database (Denmark)

Kahle, Lynn; Eriksen, Steen Mandsfelt

2016-01-01

Morten Wagener is a Danish design, and innovator who founded the cargo and personal transportation bicycle company, ”Butchers and Bicycles,”. He identified a business opportunity to improve the future of urban transport. His idea was that most of the trikes) on the market lacked good design......, maneuverability and styling. With his engineering and design background, Wagener set out to design a new trike; which would meet the needs of the target market, which his research identified as well- educated individuals who were very interested in aesthetics. Furthermore, Wagener was convinced that trikes were...... between order and delivery. From a marketing perspective, one of the differentiating factors of Morten’s product is the quality of the ride (compared to competing products) and so his marketing team coined the slogan “Built-to-Tilt” because even though it’s a trike it feels like riding a two...

Exercise-Induced Secretion of FGF21 and Follistatin Are Blocked by Pancreatic Clamp and Impaired in Type 2 Diabetes

DEFF Research Database (Denmark)

Hansen, Jakob Schiøler; Pedersen, Bente Klarlund; Xu, Guowang

2016-01-01

blocking the increase in the glucagon to insulin ratio. In addition, we evaluated exercise-induced plasma FGF21 and follistatin in patients with T2D compared with healthy controls in response to 1 hour of bicycle exercise followed by a 3-hour recovery period. RESULTS: In healthy individuals, we observed......CONTEXT: Hepatokines have emerged as liver-derived hormone-like factors. Plasma fibroblast growth factor (FGF)-21 and follistatin increase with a high glucagon to insulin ratio and exercise, and resting levels are elevated in patients with type 2 diabetes (T2D). OBJECTIVE: The objective...... of the study was to investigate the regulatory roles of glucagon to insulin ratio and T2D on exercise-induced FGF21 and follistatin secretion. Design /Interventions: Young healthy males performed a 2-hour bicycle exercise bout followed by 5 hours of rest in supine position with and without a pancreatic clamp...

A study on electric bicycle energy efficiency

Directory of Open Access Journals (Sweden)

Ivan EVTIMOV

2015-09-01

Full Text Available The paper presents a construction of an experimental electric bicycle for evaluation of the energy efficiency. The bicycle is equipped with onboard computer which can store the information about motion and energy consumption. The result concerning power, energy consumption, recharging during brake process, etc. are given. Energy consumption for 3 typical city routes is studied.

The spatio-temporal Development of Copenhagen's bicycle infrastructure 1912-2013

DEFF Research Database (Denmark)

Carstensen, Trine Agervig; Olafsson, Anton Stahl; Bech, Nynne Marie

2015-01-01

Cycling plays an important role in low-carbon transitions. Around the globe, cities are constructing bicycle infrastructure. The city of Copenhagen has a bicycle-friendly infrastructure celebrated for its fine-meshed network. This study documents the spatio-temporal development of Copenhagen......’s bicycle infrastructure and explores how the development corresponds to other processes of urban transformation. The study builds on historical maps of bicycle infrastructure that are digitised into geographical information, which allows for a comprehensive analysis of the formation of the network....... In search for identifying drivers, the study analyses the city’s spatial growth pattern, migration pattern, development of road network and changes in the transport culture. Analyses reveal that the bicycle infrastructure expanded at a relatively constant pace during distinct periods of urban transformation...

Finding the speed of a bicycle in circular motion by measuring the lean angle of the bicycle

Science.gov (United States)

Ben-Abu, Yuval; Wolfson, Ira; Yizhaq, Hezi

2018-05-01

We suggest an activity for measuring the speed of a bicycle going in circular motion by measuring the bicycle’s lean angle. In this activity students will be able to feel the strength that is being activated on their bodies while they are moving in circular motion. They will also understand that it is impossible to ride in a circle without the bicycle leaning at an angle, an action that is performed intuitively.

Bicycle safety education for children from a developmental and learning perspective.

Science.gov (United States)

2014-01-01

When children ride bicycles in and near traffic, they engage in a complicated task of combining motor skills and cognitive skills. In addition to developing bicycle-handling skills, bicycle safety education programs teach children how to ride safely ...

Synthetic strategy for bicyclic tetrapeptides HDAC inhibitors using ...

Indian Academy of Sciences (India)

Cyclic peptides show diverse biological activities and are considered as good therapeutic agents due to structural rigidity, receptor selectivity and biochemical stability. We have developed bicyclic tetrapeptide HDAC inhibitors based on different cyclic tetrapeptide scaffolds. For the synthesis of these bicyclic tetrapeptides, ...

40 CFR 52.1162 - Regulation for bicycle use.

Science.gov (United States)

2010-07-01

... safety education for bicyclists, motorists, children, students, street maintenance personnel and... as for a program of bicycle safety education including the motor vehicle operators license... bicycles share road space with motorized vehicles. (5) Bikeway means bike paths, bike lanes and bike routes...

Safety effects of permanent running lights for bicycles

DEFF Research Database (Denmark)

Madsen, Jens Chr. Overgaard; Andersen, T.; Lahrmann, Harry

2013-01-01

Making the use of daytime running lights mandatory for motor vehicles is generally documented to have had a positive impact upon traffic safety. Improving traffic safety for bicyclists is a focal point in the road traffic safety work in Denmark. In 2004 and 2005 a controlled experiment including...... 3845 cyclists was carried out in Odense, Denmark in order to examine, if permanent running lights mounted to bicycles would improve traffic safety for cyclists. The permanent running lights were mounted to 1845 bicycles and the accident rate was recorded through 12 months for this treatment group...... and 2000 other bicyclists, the latter serving as a control group without bicycle running lights. The safety effect of the running lights is analysed by comparing incidence rates – number of bicycle accidents recorded per man-month – for the treatment group and the control group. The incidence rate...

EFFECT OF EXERCISE ON CYCLE LENGTH IN ATRIAL-FLUTTER

NARCIS (Netherlands)

VANDENBERG, MP; CRIJNS, HJGM; SZABO, BM; BROUWER, J; LIE, KI

Objective-To examine the effect of exercise on cycle length in atrial flutter. Patients-15 patients with chronic atrial flutter. Seven patients were taking digoxin and six verapamil; two were not taking medication. Methods-All patients underwent bicycle ergometry. Flutter cycle length was measured

Reduced Dynamics of the Non-holonomic Whipple Bicycle

Science.gov (United States)

Boyer, Frédéric; Porez, Mathieu; Mauny, Johan

2018-06-01

Though the bicycle is a familiar object of everyday life, modeling its full nonlinear three-dimensional dynamics in a closed symbolic form is a difficult issue for classical mechanics. In this article, we address this issue without resorting to the usual simplifications on the bicycle kinematics nor its dynamics. To derive this model, we use a general reduction-based approach in the principal fiber bundle of configurations of the three-dimensional bicycle. This includes a geometrically exact model of the contacts between the wheels and the ground, the explicit calculation of the kernel of constraints, along with the dynamics of the system free of any external forces, and its projection onto the kernel of admissible velocities. The approach takes benefits of the intrinsic formulation of geometric mechanics. Along the path toward the final equations, we show that the exact model of the bicycle dynamics requires to cope with a set of non-symmetric constraints with respect to the structural group of its configuration fiber bundle. The final reduced dynamics are simulated on several examples representative of the bicycle. As expected the constraints imposed by the ground contacts, as well as the energy conservation, are satisfied, while the dynamics can be numerically integrated in real time.

Exercise testing in Warmblood sport horses under field conditions.

Science.gov (United States)

Munsters, Carolien C B M; van Iwaarden, Alexandra; van Weeren, René; Sloet van Oldruitenborgh-Oosterbaan, Marianne M

2014-10-01

Regular exercise testing in Warmblood sport horses may, as in racing, potentially help to characterise fitness indices in different disciplines and at various competition levels and assist in understanding when a horse is 'fit to compete'. In this review an overview is given of the current state of the art of exercise testing in the Olympic disciplines of eventing, show jumping and dressage, and areas for further development are defined. In event horses, a simple four-step incremental exercise test measuring heart rate (HR), lactate concentration (LA) and velocity (V) is most often used. In dressage and riding horses, a wide variety of exercise tests have been developed, including incremental exercise tests, indoor riding tests and lunging tests. In show jumping, the use of a five-step incremental exercise test and exercise tests evaluating technical skills and fatigue of the horse has been reported. The velocity at a plasma LA of 4 mmol/L (VLA4) and HR recovery during submaximal exercise intensity have been shown to be the best parameters in event horses for predicting performance and impending injuries. In riding horses, the fitness level of horses is also an important determinant of injuries. Implementation of regular exercise testing and monitoring of training sessions may have important added value in the assessment of performance ability and potential future injuries in Warmblood sport horses. However, there is an urgent need to standardise methodologies and outcome parameters in order to make results comparable. Copyright © 2014 Elsevier Ltd. All rights reserved.

Bicycling to school improves the cardiometabolic risk factor profile

DEFF Research Database (Denmark)

Ostergaard, Lars; Børrestad, Line A B; Tarp, Jakob

2012-01-01

To investigate whether bicycling to school improves cardiometabolic risk factor profile and cardiorespiratory fitness among children.......To investigate whether bicycling to school improves cardiometabolic risk factor profile and cardiorespiratory fitness among children....

Using crowdsourcing to prioritize bicycle network improvements : final report.

Science.gov (United States)

2016-04-01

Effort to improve the bicycle route network using crowdsourced data is a powerful means : of incorporating citizens in infrastructure improvement decisions, which will improve : livability by maximizing the benefit of the bicycle infrastructure fundi...

Exercise intensity levels in children with cerebral palsy while playing with an active video game console.

Science.gov (United States)

Robert, Maxime; Ballaz, Laurent; Hart, Raphael; Lemay, Martin

2013-08-01

Children with cerebral palsy (CP) are prone to secondary complications related to physical inactivity and poor cardiorespiratory capacity. This problem could be greatly attenuated through the use of video games that incorporate physical activity for 2 reasons: Video games already represent an important component of leisure time in younger people, and such games can lead to a high level of exercise intensity in people who are healthy. The study objective was to evaluate exercise intensity in children with spastic diplegic CP and children who were typically developing while playing with an active video game console. This was a cross-sectional study. Ten children (7-12 years old) with spastic diplegic CP (Gross Motor Function Classification System level I or II) and 10 children who were age matched and typically developing were evaluated in a movement analysis laboratory. Four games were played with the active video game console (jogging, bicycling, snowboarding, and skiing) for 40 minutes. Heart rate was recorded during the entire playing period with a heart rate belt monitor. Exercise intensity was defined as the percentage of heart rate reserve (HRR). In addition, lower extremity motion analysis was carried out during the final minute of the playing period for the jogging and bicycling games. No difference between groups was observed for any variables. A main effect of games was observed for the amount of time spent at an intensity greater than 40% of HRR. Specifically, more than 50% of the playing time for the jogging game and more than 30% of the playing time for the bicycling game were spent at an intensity greater than 40% of HRR. In addition, the jogging game produced a larger range of motion than the bicycling game. A limitation of this study was the relatively small and heterogeneous sample. For all 4 games, similar exercise intensity levels were observed for children who were typically developing and children with CP, suggesting that children with CP could

An Operator's Guide to Safe and Enjoyable Bicycling.

Science.gov (United States)

San Jose Dept. of Public Works, CA.

Addressed to young persons and adults, this booklet delineates the duties and rights applicable to bicyclists as drivers of vehicles. The following topics are discussed: Rules of the road, defensive bicycling techniques, the bicycle as a machine, registration and theft prevention, walking the bike, bike routes, and recreational and group rides.…

Characterizing the speed and paths of shared bicycles in Lyon

OpenAIRE

Jensen , Pablo; Rouquier , Jean-Baptiste; Ovtracht , Nicolas; Robardet , Céline

2010-01-01

Thanks to numerical data gathered by Lyon's shared bicycling system V\\'elo'v, we are able to analyze 11.6 millions bicycle trips, leading to the first robust characterization of urban bikers' behaviors. We show that bicycles outstrip cars in downtown Lyon, by combining high speed and short paths.These data also allows us to calculate V\\'elo'v fluxes on all streets, pointing to interesting locations for bike paths.

Fluid Mechanics of a High Performance Racing Bicycle Wheel

Science.gov (United States)

Mercat, Jean-Pierre; Cretoux, Brieuc; Huat, Francois-Xavier; Nordey, Benoit; Renaud, Maxime; Noca, Flavio

2013-11-01

In 2012, MAVIC released the most aerodynamic bicycle wheel on the market, the CXR 80. The french company MAVIC has been a world leader for many decades in the manufacturing of bicycle wheels for competitive events such as the Olympic Games and the Tour de France. Since 2010, MAVIC has been in a research partnership with the University of Applied Sciences in Geneva, Switzerland, for the aerodynamic development of bicycle wheels. While most of the development up to date has been performed in a classical wind tunnel, recent work has been conducted in an unusual setting, a hydrodynamic towing tank, in order to achieve low levels of turbulence and facilitate quantitative flow visualization (PIV). After a short introduction on the aerodynamics of bicycle wheels, preliminary fluid mechanics results based on this novel setup will be presented.

Benefits of HIV testing during military exercises.

Science.gov (United States)

Gross, M L; Rendin, R W; Childress, C W; Kerstein, M D

1989-12-01

During U.S. Marine Corps Reserve summer 2-week active duty for training periods, 6,482 people were tested for human immunodeficiency virus (HIV). Testing at an initial exercise, Solar Flare, trained a cadre of contact teams to, in turn, train other personnel in phlebotomy and the HIV protocol at three other exercises (141 Navy Reserve and Inspector-Instructor hospital corpsmen were trained). Corpsmen could be trained with an indoctrination of 120 minutes and a mean of 15 phlebotomies. After 50 phlebotomies, the administration, identification, and labeling process plus phlebotomy could be completed in 90 seconds. HIV testing during military exercises is both good for training and cost-effective.

Use and activity levels on newly built bicycle playgrounds

DEFF Research Database (Denmark)

Schipperijn, Jasper; Hansen, Christine Kier; Rask, Simon

2015-01-01

Increasing the use of urban green space (UGS) as well as increasing cycling could potentially help address the growing inactivity problem. Three bicycle playgrounds were designed based on a participatory process and afterwards constructed in the UGS along a cycle-route on the historic outer defence...... close to one of the sites. A future study involving objective before and after measures when a new bicycle playground is build will be needed to reveal if bicycle playgrounds can provide additional activity to its users, or ‘just’ a different type of activity, in a different location....

An improved multi-value cellular automata model for heterogeneous bicycle traffic flow

Energy Technology Data Exchange (ETDEWEB)

Jin, Sheng [College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310058 China (China); Qu, Xiaobo [Griffith School of Engineering, Griffith University, Gold Coast, 4222 Australia (Australia); Xu, Cheng [Department of Transportation Management Engineering, Zhejiang Police College, Hangzhou, 310053 China (China); College of Transportation, Jilin University, Changchun, 130022 China (China); Ma, Dongfang, E-mail: mdf2004@zju.edu.cn [Ocean College, Zhejiang University, Hangzhou, 310058 China (China); Wang, Dianhai [College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, 310058 China (China)

2015-10-16

This letter develops an improved multi-value cellular automata model for heterogeneous bicycle traffic flow taking the higher maximum speed of electric bicycles into consideration. The update rules of both regular and electric bicycles are improved, with maximum speeds of two and three cells per second respectively. Numerical simulation results for deterministic and stochastic cases are obtained. The fundamental diagrams and multiple states effects under different model parameters are analyzed and discussed. Field observations were made to calibrate the slowdown probabilities. The results imply that the improved extended Burgers cellular automata (IEBCA) model is more consistent with the field observations than previous models and greatly enhances the realism of the bicycle traffic model. - Highlights: • We proposed an improved multi-value CA model with higher maximum speed. • Update rules are introduced for heterogeneous bicycle traffic with maximum speed 2 and 3 cells/s. • Simulation results of the proposed model are consistent with field bicycle data. • Slowdown probabilities of both regular and electric bicycles are calibrated.

An improved multi-value cellular automata model for heterogeneous bicycle traffic flow

International Nuclear Information System (INIS)

Jin, Sheng; Qu, Xiaobo; Xu, Cheng; Ma, Dongfang; Wang, Dianhai

2015-01-01

This letter develops an improved multi-value cellular automata model for heterogeneous bicycle traffic flow taking the higher maximum speed of electric bicycles into consideration. The update rules of both regular and electric bicycles are improved, with maximum speeds of two and three cells per second respectively. Numerical simulation results for deterministic and stochastic cases are obtained. The fundamental diagrams and multiple states effects under different model parameters are analyzed and discussed. Field observations were made to calibrate the slowdown probabilities. The results imply that the improved extended Burgers cellular automata (IEBCA) model is more consistent with the field observations than previous models and greatly enhances the realism of the bicycle traffic model. - Highlights: • We proposed an improved multi-value CA model with higher maximum speed. • Update rules are introduced for heterogeneous bicycle traffic with maximum speed 2 and 3 cells/s. • Simulation results of the proposed model are consistent with field bicycle data. • Slowdown probabilities of both regular and electric bicycles are calibrated

Sociodemographic Factors, Population Density, and Bicycling for Transportation in the United States.

Science.gov (United States)

Nehme, Eileen K; Pérez, Adriana; Ranjit, Nalini; Amick, Benjamin C; Kohl, Harold W

2016-01-01

Transportation bicycling is a behavior with demonstrated health benefits. Population-representative studies of transportation bicycling in United States are lacking. This study examined associations between sociodemographic factors, population density, and transportation bicycling and described transportation bicyclists by trip purposes, using a US-representative sample. This cross-sectional study used 2009 National Household Travel Survey datasets. Associations among study variables were assessed using weighted multivariable logistic regression. On a typical day in 2009, 1% of Americans older than 5 years of age reported a transportation bicycling trip. Transportation cycling was inversely associated with age and directly with being male, with being white, and with population density (≥ 10,000 vs transportation. Twenty-one percent of transportation bicyclists reported trips to work, whereas 67% reported trips to social or other activities. Transportation bicycling in the United States is associated with sociodemographic characteristics and population density. Bicycles are used for a variety of trip purposes, which has implications for transportation bicycling research based on commuter data and for developing interventions to promote this behavior.

Successful Swiss solar bicycles in Australia

International Nuclear Information System (INIS)

Hansen, K.

2000-01-01

The article takes a look at the Swiss 'Spirit of Bike' team's success in the 'Power Challenge' race across Australia using solar-bicycles based on commercially available models. Apart from the sporting aspects of race, technical details on the cycles and their supply of solar power are given. Also, the history behind the success of the team is presented and the monitoring of man (and woman) and machine during the race is described. The article also discusses the electric bicycles that are commercially available and the potential of these energy-efficient vehicles in Switzerland

Development of a solar-powered electric bicycle in bike sharing transportation system

Science.gov (United States)

Adhisuwignjo, S.; Siradjuddin, I.; Rifa'i, M.; Putri, R. I.

2017-06-01

The increasing mobility has directly led to deteriorating traffic conditions, extra fuel consumption, increasing automobile exhaust emissions, air pollution and lowering quality of life. Apart from being clean, cheap and equitable mode of transport for short-distance journeys, cycling can potentially offer solutions to the problem of urban mobility. Many cities have tried promoting cycling particularly through the implementation of bike-sharing. Apparently the fourth generation bikesharing system has been promoted utilizing electric bicycles which considered as a clean technology implementation. Utilization of solar power is probably the development keys in the fourth generation bikesharing system and will become the standard in bikesharing system in the future. Electric bikes use batteries as a source of energy, thus they require a battery charger system which powered from the solar cells energy. This research aims to design and implement electric bicycle battery charging system with solar energy sources using fuzzy logic algorithm. It is necessary to develop an electric bicycle battery charging system with solar energy sources using fuzzy logic algorithm. The study was conducted by means of experimental method which includes the design, manufacture and testing controller systems. The designed fuzzy algorithm have been planted in EEPROM microcontroller ATmega8535. The charging current was set at 1.2 Amperes and the full charged battery voltage was observed to be 40 Volts. The results showed a fuzzy logic controller was able to maintain the charging current of 1.2 Ampere with an error rate of less than 5% around the set point. The process of charging electric bike lead acid batteries from empty to fully charged was 5 hours. In conclusion, the development of solar-powered electric bicycle controlled using fuzzy logic controller can keep the battery charging current in solar-powered electric bicycle to remain stable. This shows that the fuzzy algorithm can be used as

On the influence of tyre and structural properties on the stability of bicycles

Science.gov (United States)

Doria, Alberto; Roa Melo, Sergio Daniel

2018-06-01

In recent years the Whipple Carvallo Bicycle Model has been extended to analyse high speed stability of bicycles. Various researchers have developed models taking into account the effects of front frame compliance and tyre properties, nonetheless, a systematic analysis has not been yet carried out. This paper aims at analysing parametrically the influence of front frame compliance and tyre properties on the open loop stability of bicycles. Some indexes based on the eigenvalues of the dynamic system are defined to evaluate quantitatively bicycle stability. The parametric analysis is carried out with a factorial design approach to determine the most influential parameters. A commuting and a racing bicycle are considered and numerical results show different effects of the various parameters on each bicycle. In the commuting bicycle, the tyre properties have greater influence than front frame compliance, and the weave mode has the main effect on stability. Conversely, in the racing bicycle, the front frame compliance parameters have greater influence than tyre properties, and the wobble mode has the main effect on stability.

Association between exercise intensity and renal blood flow evaluated using ultrasound echo.

Science.gov (United States)

Kawakami, Shotaro; Yasuno, Tetsuhiko; Matsuda, Takuro; Fujimi, Kanta; Ito, Ai; Yoshimura, Saki; Uehara, Yoshinari; Tanaka, Hiroaki; Saito, Takao; Higaki, Yasuki

2018-03-10

High-intensity exercise reduces renal blood flow (RBF) and may transiently exacerbate renal dysfunction. RBF has previously been measured invasively by administration of an indicator material; however, non-invasive measurement is now possible with technological innovations. This study examined variations in RBF at different exercise intensities using ultrasound echo. Eight healthy men with normal renal function (eGFR cys 114 ± 19 mL/min/1.73 m 2 ) participated in this study. Using a bicycle ergometer, participants underwent an incremental exercise test using a ramp protocol (20 W/min) until exhaustion in Study 1 and the lactate acid breaking point (LaBP) was calculated. Participants underwent a multi-stage test at exercise intensities of 60, 80, 100, 120, and 140% LaBP in Study 2. RBF was measured by ultrasound echo at rest and 5 min after exercise in Study 1 and at rest and immediately after each exercise in Study 2. To determine the mechanisms behind RBF decline, a catheter was placed into the antecubital vein to study vasoconstriction dynamics. RBF after maximum exercise decreased by 51% in Study 1. In Study 2, RBF showed no significant decrease until 80% LaBP, and showed a significant decrease (31%) at 100% LaBP compared with at rest (p blood lactate. Reduction in RBF with exercise above the intensity at LaBP was due to decreased cross-sectional area rather than time-averaged flow velocity.

Predictive Accuracy of Exercise Stress Testing the Healthy Adult.

Science.gov (United States)

Lamont, Linda S.

1981-01-01

Exercise stress testing provides information on the aerobic capacity, heart rate, and blood pressure responses to graded exercises of a healthy adult. The reliability of exercise tests as a diagnostic procedure is discussed in relation to sensitivity and specificity and predictive accuracy. (JN)

Associations between bicycling and carotid arterial stiffness in adolescents

DEFF Research Database (Denmark)

Ried-Larsen, M; Grøntved, A; Østergaard, Lars

2015-01-01

Youth Heart Study. Total frequency of bicycle usage was assessed by self-report, and carotid arterial stiffness was assessed using B-mode ultrasound. After adjusting for pubertal status, body height, and objectively measured physical activity and other personal lifestyle and demographic factors, boys......The aim of the study was to investigate the associations between bicycling and carotid arterial stiffness, independent of objectively measured moderate-and-vigorous physical activity. This cross-sectional study included 375 adolescents (age 15.7 ± 0.4 years) from the Danish site of the European...... using their bicycle every day of the week displayed a higher carotid arterial compliance {standard beta 0.47 [95% confidence interval (CI) 0.07-0.87]} and distension [standard beta 0.38 (95% CI -0.04 to 0.81)]. Boys using their bicycle every day of the week furthermore displayed a lower Young's elastic...

N-terminal pro-atrial natriuretic peptide response to acute exercise in depressed patients and healthy controls

DEFF Research Database (Denmark)

Krogh, Jesper; Ströhle, Andreas; Westrin, Asa

2011-01-01

that patients with depression would have an attenuated N-terminal proANP (NT-proANP) response to acute exercise compared to healthy controls. Secondly, we aimed to assess the effect of antidepressants on NT-proANP response to acute exercise. METHODS: We examined 132 outpatients with mild to moderate depression......BACKGROUND: The dysfunction of hypothalamic-pituitary-adrenal (HPA) axis in major depression includes hyperactivity and reduced feedback inhibition. Atrial natriuretic peptide (ANP) is able to reduce the HPA-axis response to stress and has an anxiolytic effect in rodents and humans. We hypothesized...... (ICD-10) and 44 healthy controls, group matched for age, sex, and BMI. We used an incremental bicycle ergometer test as a physical stressor. Blood samples were drawn at rest, at exhaustion, and 15, 30, and 60min post-exercise. RESULTS: The NT-proANP response to physical exercise differed between...

N-terminal pro-atrial natriuretic peptide response to acute exercise in depressed patients and healthy controls

DEFF Research Database (Denmark)

Krogh, Jesper; Ströhle, Andreas; Westrin, Asa

2011-01-01

BACKGROUND: The dysfunction of hypothalamic-pituitary-adrenal (HPA) axis in major depression includes hyperactivity and reduced feedback inhibition. Atrial natriuretic peptide (ANP) is able to reduce the HPA-axis response to stress and has an anxiolytic effect in rodents and humans. We hypothesized...... that patients with depression would have an attenuated N-terminal proANP (NT-proANP) response to acute exercise compared to healthy controls. Secondly, we aimed to assess the effect of antidepressants on NT-proANP response to acute exercise. METHODS: We examined 132 outpatients with mild to moderate depression...... (ICD-10) and 44 healthy controls, group matched for age, sex, and BMI. We used an incremental bicycle ergometer test as a physical stressor. Blood samples were drawn at rest, at exhaustion, and 15, 30, and 60min post-exercise. RESULTS: The NT-proANP response to physical exercise differed between...

Johnson Space Center's Free Range Bicycle Program.- Fall 2015 Intern Report

Science.gov (United States)

Lee-Stockton, Willem

2015-01-01

NASA's Johnson Space Center is a big place, encompassing 1,620 acres and more than a hundred buildings. Furthermore, there are reportedly 15 thousand employees, all of which have somewhere to be. To facilitate the movement of all these people JSC has historically relied on human power. Pedaling their way towards deep space, bicycles have been the go to method. Currently there are about 200 Free Range Bicycles at JSC. Free Range Bicycles belong to nobody, except NASA, and are available for anybody to use. They are not to be locked or hidden (although frequently are) and the intention is that there will always be a bike to hop on to get where you're going (although it may not be the bike you rode in on). Although not without its own shortcomings, the Free Range Bicycle Program has continued to provide low cost, simple transportation for NASA's JSC. In addition to the approximately 200 Free Range Bicycles, various larger divisions (like engineering) will often buy a few dozen bikes for their team members to use or individuals will bring their own personal bike to either commute or use on site. When these bicycles fall into disrepair or are abandoned (from retirees etc) they become a problem at JSC. They are an eye sore, create a safety hazard and make it harder to find a working bike in a time of need. The Free Range Program hopes to address this first problem by "tagging out" abandoned or out of service bicycles. A bright orange "DO NOT OPERATE" tag is placed on the bike and given a serial number for tracking purposes. See picture to the right. If the bike has an active owner with intentions to repair the bike the bottom of the tag has instructions for how to claim the abandoned bicycle. After being tagged the owner of the bicycle has 30 days to claim the bicycle and either haul it off site or get it repaired (and labeled) in accordance with Johnson's Bicycle Policy. If the abandoned bicycle is not claimed within 30 days it becomes the property of the Government. The

How similar are two-unit bicycle and motorcycle crashes?

Science.gov (United States)

Haworth, Narelle; Debnath, Ashim Kumar

2013-09-01

This paper explores the similarities and differences between bicycle and motorcycle crashes with other motor vehicles. If similar treatments can be effective for both bicycle and motorcycle crashes, then greater benefits in terms of crash costs saved may be possible for the same investment in treatments. To reduce the biases associated with under-reporting of these crashes to police, property damage and minor injury crashes were excluded. The most common crash type for both bicycles (31.1%) and motorcycles (24.5%) was intersection from adjacent approaches. Drivers of other vehicles were coded most at fault in the majority of two-unit bicycle (57.0%) and motorcycle crashes (62.7%). The crash types, patterns of fault and factors affecting fault were generally similar for bicycle and motorcycle crashes. This confirms the need to combat the factors contributing to failure of other drivers to yield right of way to two-wheelers, and suggest that some of these actions should prove beneficial to the safety of both motorized and non-motorized two-wheelers. In contrast, child bicyclists were more often at fault, particularly in crashes involving a vehicle leaving the driveway or footpath. The greater reporting of violations by riders and drivers in motorcycle crashes also deserves further investigation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Investigating the Views of Male Students on Using Bicycles Based on the Theory of Planned Behavior in Yazd University of Medical Sciences, 2012

Directory of Open Access Journals (Sweden)

MH Baghianimoghadam

2014-11-01

Full Text Available Introduction: Today, it is somewhat possible for general Population to use bicycle as a means of transportation or sport. Physical activity is considered as an important strategy for the prevention and treatment of obesity and other critical metabolic diseases in the different ages of life. Since the Theory of Planned Behavior assesses perceived control beliefs about behaviors, it seems appropriate to study exercise. In the study, the views of male students - as a group which are affective on community norms- about bicycle use were investigated. Method: In this cross-sectional study 250 male students in Yazd University of Medical Sciences responded to a researcher made questionnaire which was designed for assessing their views about bicycle use, based on the Theory of Planned Behavior. The data were analyzed using SPSS v16. Results: The mean age of participants was 23. 01± 3. 83. Findings revealed that the scale means of the theory constructs were as follows: behavioral intention: 8. 54 ±3. 9, Attitude: 2. 97 ± 15. 2, subjective norm: 12. 1± 2. 9 and perceived behavioral control: 17. 5 ±4. 6. Regression analysis indicated that attitude and subjective norm explained 29. 7% of behavioral intention variations (P<0. 001. Conclusion: According to results which indicated that Attitude and subjective norm had more powerful relationship with and predictive power of behavioral intention about using bicycle it is recommended that cultural activities and interventions may be effective to promote using bicycle among students.

A Novel Electric Bicycle Battery Monitoring System Based on Android Client

Directory of Open Access Journals (Sweden)

Chuanxue Song

2017-01-01

Full Text Available The battery monitoring system (BMS plays a crucial role in maintaining the safe operation of the lithium battery electric bicycle and prolonging the life of the battery pack. This paper designed a set of new battery monitoring systems based on the Android system and ARM single-chip microcomputer to enable direct management of the lithium battery pack and convenient monitoring of the state of the battery pack. The BMS realizes the goal of monitoring the voltage, current, and ambient temperature of lithium batteries, estimating the state of charge (SOC and state of health (SOH, protecting the battery from abuse during charging or discharging, and ensuring the consistency of the batteries by integrating the passive equalization circuit. The BMS was proven effective and feasible through several tests, including charging/discharging, estimation accuracy, and communication tests. The results indicated that the BMS could be used in the design and application of the electric bicycle.

Acute physical exercise affected processing efficiency in an auditory attention task more than processing effectiveness.

Science.gov (United States)

Dutke, Stephan; Jaitner, Thomas; Berse, Timo; Barenberg, Jonathan

2014-02-01

Research on effects of acute physical exercise on performance in a concurrent cognitive task has generated equivocal evidence. Processing efficiency theory predicts that concurrent physical exercise can increase resource requirements for sustaining cognitive performance even when the level of performance is unaffected. This hypothesis was tested in a dual-task experiment. Sixty young adults worked on a primary auditory attention task and a secondary interval production task while cycling on a bicycle ergometer. Physical load (cycling) and cognitive load of the primary task were manipulated. Neither physical nor cognitive load affected primary task performance, but both factors interacted on secondary task performance. Sustaining primary task performance under increased physical and/or cognitive load increased resource consumption as indicated by decreased secondary task performance. Results demonstrated that physical exercise effects on cognition might be underestimated when only single task performance is the focus.

A Modified Cellular Automaton Approach for Mixed Bicycle Traffic Flow Modeling

Directory of Open Access Journals (Sweden)

Xiaonian Shan

2015-01-01

Full Text Available Several previous studies have used the Cellular Automaton (CA for the modeling of bicycle traffic flow. However, previous CA models have several limitations, resulting in differences between the simulated and the observed traffic flow features. The primary objective of this study is to propose a modified CA model for simulating the characteristics of mixed bicycle traffic flow. Field data were collected on physically separated bicycle path in Shanghai, China, and were used to calibrate the CA model using the genetic algorithm. Traffic flow features between simulations of several CA models and field observations were compared. The results showed that our modified CA model produced more accurate simulation for the fundamental diagram and the passing events in mixed bicycle traffic flow. Based on our model, the bicycle traffic flow features, including the fundamental diagram, the number of passing events, and the number of lane changes, were analyzed. We also analyzed the traffic flow features with different traffic densities, traffic components on different travel lanes. Results of the study can provide important information for understanding and simulating the operations of mixed bicycle traffic flow.

Cardiorespiratory benefits of group exercise among adults with serious mental illness.

Science.gov (United States)

Jerome, Gerald J; Young, Deborah Rohm; Dalcin, Arlene T; Wang, Nae-Yuh; Gennusa, Joseph; Goldsholl, Stacy; Appel, Lawrence J; Daumit, Gail L

2017-10-01

This study examined cardiorespiratory fitness (CRF) among adults with serious mental illness (SMI) participating in group exercise classes. Overweight and obese adults with SMI were randomized to either a control condition or a weight management condition with group exercise classes (n = 222). Submaximal bicycle ergometry was used to assess CRF at baseline, 6 and 18 months. Those with ≥ 66% participation in the exercise classes had a lower heart rate response at 6 and 18 month follow-up. Participation in group exercise classes was associated with improved short and long term cardiovascular fitness among adults with SMI. Copyright © 2017 Elsevier B.V. All rights reserved.

Associations between a walkability index and bicycle use in Denmark

DEFF Research Database (Denmark)

Madsen, T.; Christiansen, L.; Nielsen, Thomas Alexander Sick

2012-01-01

/day, and important health benefits can accrue from regular commuting cycling. Studies have shown a positive correlation between walkability attributes of neighborhood environments (street connectivity, and use mix, residential density, retail floor area ratio) and cycling. Results from Australia/Belgium show...... associations between measures of walkability and bicycle use for transport and the present study focuses on exploring whether these findings can be applied to a Danish setting where cycling culture differs and bicycle share is much higher (17% of all trips are by bicycle)...

Exercise-induced rhabdomyolysis from stationary biking: a case report.

Science.gov (United States)

Inklebarger, J; Galanis, N; Kirkos, J; Kapetanos, G

2010-10-01

There are several reports concerning exercise and rabdomyolysis. There has been no report in the English literature of exercise induced rabdomyolisis from a stationary bike.A 63-year-old female recreational athlete presented to our hospital seeking treatment for lower back, leg pain and stiffness after exercising on a stationary bicycle one day prior. Blood work showed a raised CK of 38,120 U/L, a myoglobin of 5330 and an AST 495 U/L with normal urea and electrolytes. Urinalysis remained negative. She was admitted for oral and intravenous hydration and fluid balance monitoringThis is a very rare case of rhabdomyolysis due to exercise. This study highlights the difficulties faced by accident and emergency teams in distinguishing delayed onset muscle soreness (DOMS) from exercise-induced rhabdomyolysis, and reinforces the concept that rhabdomyolysis can occur at any level of exercise intensity.

Normal values for cardiopulmonary exercise testing in children

NARCIS (Netherlands)

ten Harkel, A.D.J.; Takken, T.; van Osch-Gevers, M.; Helbing, W.A.

BACKGROUND: A reference set of data of normal values of newly developed cardiopulmonary parameters of exercise testing in an 8-18-year-old population is lacking. PATIENTS AND METHODS: Cardiopulmonary exercise testing was performed in 175 healthy school children (8-18 years old). Continuous

Reviving a ghost in the history of technology: the social construction of the recumbent bicycle.

Science.gov (United States)

Ahmed, Hassaan; Qureshi, Omer Masood; Khan, Abid Ali

2015-02-01

Recumbent bicycles have never truly been associated with international cycling. Conventional safety (upright) bicycles have long been at the center of the cycling world, for both sport and transportation. This is despite the fact that recumbent bicycles are faster, more comfortable, and more efficient than the upright bicycles. The aim of this article is to explain the historical and social perspectives that led to the rejection of the recumbent bicycle by utilizing the theory of Social Construction of Technology (SCOT) and Bijker's two power theory, providing a contrast with the adoption of the safety bicycle.

Methods to assess the stability of a bicycle rider system

NARCIS (Netherlands)

Cooke, A.G.; Bulsink, Vera Elisabeth; Beusenberg, Mark; Dubbeldam, Rosemary; Bonnema, Gerrit Maarten; Poelman, Wim; Koopman, Hubertus F.J.M.

2012-01-01

The SOFIE (Intelligent Assisted Bicycles) project wishes to create performance and design guidelines for mechatronic appliances which improve the stability of electric bicycles, so-called intelligent stability assist devices (IAD). To achieve this goal, a stability hypothesis, an advanced

Effect of test exercises and mask donning on measured respirator fit.

Science.gov (United States)

Crutchfield, C D; Fairbank, E O; Greenstein, S L

1999-12-01

Quantitative respirator fit test protocols are typically defined by a series of fit test exercises. A rationale for the protocols that have been developed is generally not available. There also is little information available that describes the effect or effectiveness of the fit test exercises currently specified in respiratory protection standards. This study was designed to assess the relative impact of fit test exercises and mask donning on respirator fit as measured by a controlled negative pressure and an ambient aerosol fit test system. Multiple donnings of two different sizes of identical respirator models by each of 14 test subjects showed that donning affects respirator fit to a greater degree than fit test exercises. Currently specified fit test protocols emphasize test exercises, and the determination of fit is based on a single mask donning. A rationale for a modified fit test protocol based on fewer, more targeted test exercises and multiple mask donnings is presented. The modified protocol identified inadequately fitting respirators as effectively as the currently specified Occupational Safety and Health Administration (OSHA) quantitative fit test protocol. The controlled negative pressure system measured significantly (p < 0.0001) more respirator leakage than the ambient aerosol fit test system. The bend over fit test exercise was found to be predictive of poor respirator fit by both fit test systems. For the better fitting respirators, only the talking exercise generated aerosol fit factors that were significantly lower (p < 0.0001) than corresponding donning fit factors.

36 CFR 1004.30 - Bicycles.

Science.gov (United States)

2010-07-01

... parking area to bicycle use pursuant to the criteria and procedures of §§ 1001.5 and 1001.7 of this... consistent with the protection of natural, scenic and aesthetic values, safety considerations and management...

Using magnetorheological fluids in an innovative hybrid bicycle damper

International Nuclear Information System (INIS)

Shiao, Y J; Nguyen, T S

2015-01-01

Magnetorheological fluids are capable of changing their viscosity quickly. This can provide good controllability and fast dynamic response. A conventional passive suspension system with air spring or hydraulic damper has simple design and financial benefit for bicycles, but its operation is uncontrollable and non-adaptive. This paper presented a semi-active hybrid bicycle suspension system which combines conventional air spring and a new magnetorheological damping brake together to reduce vibration of a bicycle. A multi-layer magnetorheological brake and linkage mechanism are connected to bike fork to form the adaptive damping part of the innovative hybrid suspension system. The simulation results proved that the semi-active suspension system can reduce bike vibration effectively. (paper)

Relationship between the Pedaling Biomechanics and Strain of Bicycle Frame during Submaximal Tests

Directory of Open Access Journals (Sweden)

Aneliya V. Manolova

2015-06-01

Full Text Available The aim of this study was to analyse the effect of forces applied to pedals and cranks on the strain imposed to an instrumented bicycle motocross (BMX frame. Using results from a finite element analysis to determine the localisation of highest stress, eight strain gauges were located on the down tube, the seat tube and the right chain stay. Before the pedaling tests, static loads were applied to the frame during bench tests. Two pedaling conditions have been analysed. In the first, the rider was in static standing position on the pedals and applied maximal muscular isometric force to the right pedal. The second pedaling condition corresponds to three pedaling sprint tests at submaximal intensities at 150, 300 and 550 W on a cycle-trainer. The results showed that smaller strain was observed in the pedaling condition than in the rider static standing position condition. The highest strains were located in the seat tube and the right chain stay near the bottom bracket area. The maximum stress observed through all conditions was 41 MPa on the right chain stay. This stress was 11 times lower than the yield stress of the frame material (460 MPa. This protocol could help to adapt the frame design to the riders as a function of their force and mechanical power output. These results could also help design BMX frames for specific populations (females and rider morphology.

On-road Bicycle Pavement Markings

Data.gov (United States)

Allegheny County / City of Pittsburgh / Western PA Regional Data Center — A mile by mile breakdown of the on-street bicycle pavement markings installed within the City of Pittsburgh. These include bike lanes, shared lane markings...

A prognostic scoring system for arm exercise stress testing.

Science.gov (United States)

Xie, Yan; Xian, Hong; Chandiramani, Pooja; Bainter, Emily; Wan, Leping; Martin, Wade H

2016-01-01

Arm exercise stress testing may be an equivalent or better predictor of mortality outcome than pharmacological stress imaging for the ≥50% for patients unable to perform leg exercise. Thus, our objective was to develop an arm exercise ECG stress test scoring system, analogous to the Duke Treadmill Score, for predicting outcome in these individuals. In this retrospective observational cohort study, arm exercise ECG stress tests were performed in 443 consecutive veterans aged 64.1 (11.1) years. (mean (SD)) between 1997 and 2002. From multivariate Cox models, arm exercise scores were developed for prediction of 5-year and 12-year all-cause and cardiovascular mortality and 5-year cardiovascular mortality or myocardial infarction (MI). Arm exercise capacity in resting metabolic equivalents (METs), 1 min heart rate recovery (HRR) and ST segment depression ≥1 mm were the stress test variables independently associated with all-cause and cardiovascular mortality by step-wise Cox analysis (all pstatistic of 0.81 before and 0.88 after adjustment for significant demographic and clinical covariates. Arm exercise scores for the other outcome end points yielded C-statistic values of 0.77-0.79 before and 0.82-0.86 after adjustment for significant covariates versus 0.64-0.72 for best fit pharmacological myocardial perfusion imaging models in a cohort of 1730 veterans who were evaluated over the same time period. Arm exercise scores, analogous to the Duke Treadmill Score, have good power for prediction of mortality or MI in patients who cannot perform leg exercise.

The Comprehensive Benefit Evaluation of Take Shared Bicycles as Connecting to Public Transit

Science.gov (United States)

Zhang, J. Y.; Sun, H.; Li, P. F.; Li, C. C.

2017-10-01

Shared bicycles as an important way of connecting public transport, have few literature to evaluate its effectiveness.This paper taking Beijing city as an example, make anevaluationfor the six types of travel combinations which are commonly used by the citizens. The author selects four quantitative indicators: fuel consumption, economic cost, total time spent, and CO2 emission. And two qualitative indicators: degree of comfort and convenience. The relative efficiency of quantitative indicators is obtained by data envelopment analysis (DEA) and fuzzification and then take fuzzy synthetic evaluation with qualitative indicators.It was found that the choice of shared bicycles +subway+ shared bicycles and shared bicycles has good comprehensive benefits in medium distance travel. The findings also suggest that shared bicycles +subway+ shared bicycles is the best choice in the utilitarian trips. The conclusions not only provide suggestions for the travellers to select travel modes, but also can adjust the relevant factors to increase the proportion of green travel.

Bamboo Bicycle – Past or Future?

Directory of Open Access Journals (Sweden)

Suzana Jakovljević

2016-01-01

Full Text Available In this article the experiment was carried out to establish tensile strength values of two different bamboo species, which are obtained by the static tensile test. The tensile strength results of two tested species Tonkin Cane and Ku Zhu bamboo are presented and compared with traditional materials used for bicycle frame to determine their suitability for designing a frame. Physiology and other properties of bamboo were elaborated as well. The purpose of this study was to gain more knowledge on bamboo and prove his suitability in use as an alternative for ecologically unacceptable materials. Therefore, application of the natural materials is essential for the sustainable development. The fact that they have unlimited resources the use of bamboo has great potential and this article explains why.

The study of alteration in left ventricular volume and pressure to volume ratio during exercise in patients with coronary heart disease

International Nuclear Information System (INIS)

Liu Zhonglin; Pei Zhuguo; Zang Bin

1994-01-01

The alterations induced by exercise in left ventricular end diastolic volume index (EDVI), end systolic volume index (ESVI) and systolic blood pressure to end systolic volume ratio (P/ESV) were studied in 15 normal subjects and 42 patients with coronary heart disease using a non-geometric count-based method and supine bicycle exercise test. Normal subjects had an increase in EDVI and a decrease in ESVI, but coronary heart disease patients had an increase in both EDVI and ESVI. The extent of increase induced by exercise in EDVI was greater in angina patients than that in normal and old myocardial infarction subjects. The P/ESV can be used to evaluate left ventricular systolic pressure-volume relationship. For the P/ESV exercise response, the sensitivity, specificity and accuracy for coronary heart disease were 95%, 93% and 95%, respectively

Pediatric exercise testing. In health and disease

NARCIS (Netherlands)

Bongers, B.C.

2013-01-01

Measuring peak oxygen uptake (VO2peak) during progressive cardiopulmonary exercise testing (CPET) up to maximal exertion is widely recognized as the best single measure of aerobic exercise capacity. It is an important determinant of health, even in childhood and adolescence. Measuring VO2peak

Exercise-induced metallothionein expression in human skeletal muscle fibres

DEFF Research Database (Denmark)

Penkowa, Milena; Keller, Pernille; Keller, Charlotte

2005-01-01

in both type I and II muscle fibres. This is the first report demonstrating that MT-I + II are significantly induced in human skeletal muscle fibres following exercise. As MT-I + II are antioxidant factors that protect various tissues during pathological conditions, the MT-I + II increases post exercise......Exercise induces free oxygen radicals that cause oxidative stress, and metallothioneins (MTs) are increased in states of oxidative stress and possess anti-apoptotic effects. We therefore studied expression of the antioxidant factors metallothionein I and II (MT-I + II) in muscle biopsies obtained...... in response to 3 h of bicycle exercise performed by healthy men and in resting controls. Both MT-I + II proteins and MT-II mRNA expression increased significantly in both type I and II muscle fibres after exercise. Moreover, 24 h after exercise the levels of MT-II mRNA and MT-I + II proteins were still highly...

36 CFR 4.30 - Bicycles.

Science.gov (United States)

2010-07-01

... road or parking area to bicycle use pursuant to the criteria and procedures of §§ 1.5 and 1.7 of this... consistent with the protection of a park area's natural, scenic and aesthetic values, safety considerations...

Exercise and IL-6 infusion inhibit endotoxin-induced TNF-alpha production in humans

DEFF Research Database (Denmark)

Starkie, Rebecca; Ostrowski, Sisse Rye; Jauffred, Sune

2003-01-01

and atherosclerosis. To test this hypothesis, we performed three experiments in which eight healthy males either rested (CON), rode a bicycle for 3 h (EX), or were infused with recombinant human IL-6 (rhIL-6) for 3 h while they rested. After 2.5 h, the volunteers received a bolus of Escherichia coli...... exercise and rhIL-6 infusion at physiological concentrations inhibit endotoxin-induced TNF-alpha production in humans. Hence, these data provide the first experimental evidence that physical activity mediates antiinflammatory activity and suggest that the mechanism include IL-6, which is produced...

Structural design of a composite bicycle fork

International Nuclear Information System (INIS)

Baldissera, Paolo; Delprete, Cristiana

2014-01-01

Highlights: • Case study about composite bicycle fork design. • Special requirements for a Student Team project. • FE model to evaluate stiffness, strength and potential failure modes. • Comparison of two manufacturing approaches. • FE model stiffness validation on the manufactured fork. - Abstract: Despite the wide literature on the mechanical behaviour of carbon/epoxy composites, it is rare to find practical methodological approaches in finite element design of structural components made by laminate layup. Through the case study of a special bicycle fork needed in a Student Team prototype, this paper proposes a simplified methodology as starting point for educational and manufacturing purposes. In order to compare two manufacturing solutions in terms of stiffness, strength and failure mode, a numerical model was implemented. Since the project requirements imposed to avoid standard destructive testing, the model validation was based on a posteriori linear stiffness comparison with the manufactured component. The slight discrepancies between experimental and numerical results were discussed in order to check their origin and to assess the reliability of the model. The overall methodology, even if complain with only a part of the safety standard requirements, shows to be reliable enough and can be the basis for further extension and refinement

Getting Bicycles on Trains - Inter-modal Transport Developments in Denmark

DEFF Research Database (Denmark)

Jørgensen, Ulrik; Pedersen, Bjørn Brix

2001-01-01

The combined use of bicycles and trains has been favored in contemporary public transport policies in Denmark. Although bicycling has played a major role in Danish personal transportation in more than hundred years, the attitude from public transport authorities towards supporting bicyclists has ...... varied quite a lot....

Free Use of Bicycles at CERN

CERN Multimedia

2000-01-01

Imagine you have just arrived at CERN. You are from Russia or Japan and have no car but you do need to get around and do not like depending on public transport. What do you do? You go to the EP Service Point (Building 124) and meet Boris Cabaud to get a CERN bicycle. Use of the bicycle is free but you have to fill in an application form which needs to be signed by your Group or Division Secretary. Then the application is filled in, you are put on the waiting list and it might take you from one to four weeks to get your bike depending on the season. “Normally the bikes are only for Users in the EP division as they are paid for by the EP budget,” says Boris, “but some other divisions have made arrangements to cover the costs.” Boris takes care of 350 bicycles at present. Each bike can be lent for maximum one year. During the winter the bikes can be stored in building 301 as it is difficult to ride them in the snow. If a bike is broken or lost all costs will be billed to the group or team account of the bo...

Bicycle-bus conflict area study.

Science.gov (United States)

2009-11-01

Increasing bicycle use and bus ridership are both desirable policy goals : from a sustainability standpoint, but on city streets these two modes of : transport are often in conflict. While occupying opposite ends of the size : and weight spectrum, th...

FeNO and Exercise Testing in Children at Risk of Asthma

DEFF Research Database (Denmark)

Schoos, Ann-Marie Malby; Christiansen, Christina Figgé; Stokholm, Jakob

2017-01-01

completed in 224 seven-year-old children from the at-risk Copenhagen Prospective Studies on Asthma in Childhood2000 birth cohort. The associations between FeNO, exercise test results, and reported respiratory symptoms during exercise were analyzed adjusting for gender, respiratory infections, and inhaled....... OBJECTIVE: The objective of this study was to investigate the relationship between FeNO, exercise test results, and a history of respiratory symptoms during exercise in children at risk of asthma. METHODS: FeNO measurement, exercise testing, and interview about respiratory symptoms during exercise were...... corticosteroid treatment. The associations were also analyzed stratified by asthma and atopic status. RESULTS: Of the 224 children, 28 (13%) had an established asthma diagnosis and 58 (26%) had a positive exercise test (≥15% drop in forced expiratory volume in 1 second [FEV1] from baseline). FeNO and bronchial...

The Bicycle Compatibility Index : a level of service concept, implementation manual

Science.gov (United States)

1998-11-01

Currently, no methodology is widely accepted by engineers, planners, or bicycle coordinators that will allow them to determine how compatible a roadway is for allowing efficient operation of both bicycles and motor vehicles. Determining how existing ...

Environmental Risk Factors influencing Bicycle Theft: A Spatial Analysis in London, UK.

Directory of Open Access Journals (Sweden)

Lucy Waruguru Mburu

Full Text Available Urban authorities are continuously drawing up policies to promote cycling among commuters. However, these initiatives are counterproductive for the targeted objectives because they increase opportunities for bicycle theft. This paper explores Inner London as a case study to address place-specific risk factors for bicycle theft at the street-segment level while controlling for seasonal variation. The presence of certain public amenities (e.g., bicycle stands, railway stations, pawnshops was evaluated against locations of bicycle theft between 2013 and 2016 and risk effects were estimated using negative binomial regression models. Results showed that a greater level of risk stemmed from land-use facilities than from area-based socioeconomic status. The presence of facilities such as train stations, vacant houses, pawnbrokers and payday lenders increased bicycle theft, but no evidence was found that linked police stations with crime levels. The findings have significant implications for urban crime prevention with respect to non-residential land use.

Environmental Risk Factors influencing Bicycle Theft: A Spatial Analysis in London, UK.

Science.gov (United States)

Mburu, Lucy Waruguru; Helbich, Marco

2016-01-01

Urban authorities are continuously drawing up policies to promote cycling among commuters. However, these initiatives are counterproductive for the targeted objectives because they increase opportunities for bicycle theft. This paper explores Inner London as a case study to address place-specific risk factors for bicycle theft at the street-segment level while controlling for seasonal variation. The presence of certain public amenities (e.g., bicycle stands, railway stations, pawnshops) was evaluated against locations of bicycle theft between 2013 and 2016 and risk effects were estimated using negative binomial regression models. Results showed that a greater level of risk stemmed from land-use facilities than from area-based socioeconomic status. The presence of facilities such as train stations, vacant houses, pawnbrokers and payday lenders increased bicycle theft, but no evidence was found that linked police stations with crime levels. The findings have significant implications for urban crime prevention with respect to non-residential land use.

Costs and benefits of bicycling investments in Portland, Oregon.

Science.gov (United States)

Gotschi, Thomas

2011-01-01

Promoting bicycling has great potential to increase overall physical activity; however, significant uncertainty exists with regard to the amount and effectiveness of investment needed for infrastructure. The objective of this study is to assess how costs of Portland's past and planned investments in bicycling relate to health and other benefits. Costs of investment plans are compared with 2 types of monetized health benefits, health care cost savings and value of statistical life savings. Levels of bicycling are estimated using past trends, future mode share goals, and a traffic demand model. By 2040, investments in the range of $138 to $605 million will result in health care cost savings of $388 to $594 million, fuel savings of $143 to $218 million, and savings in value of statistical lives of $7 to $12 billion. The benefit-cost ratios for health care and fuel savings are between 3.8 and 1.2 to 1, and an order of magnitude larger when value of statistical lives is used. This first of its kind cost-benefit analysis of investments in bicycling in a US city shows that such efforts are cost-effective, even when only a limited selection of benefits is considered.

Altered gas-exchange at peak exercise in obese adolescents: implications for verification of effort during cardiopulmonary exercise testing.

Science.gov (United States)

Marinus, Nastasia; Bervoets, Liene; Massa, Guy; Verboven, Kenneth; Stevens, An; Takken, Tim; Hansen, Dominique

2017-12-01

Cardiopulmonary exercise testing is advised ahead of exercise intervention in obese adolescents to assess medical safety of exercise and physical fitness. Optimal validity and reliability of test results are required to identify maximal exercise effort. As fat oxidation during exercise is disturbed in obese individuals, it remains an unresolved methodological issue whether the respiratory gas exchange ratio (RER) is a valid marker for maximal effort during exercise testing in this population. RER during maximal exercise testing (RERpeak), and RER trajectories, was compared between obese and lean adolescents and relationships between RERpeak, RER slope and subject characteristics (age, gender, Body Mass Index [BMI], Tanner stage, physical activity level) were explored. Thirty-four obese (BMI: 35.1±5.1 kg/m²) and 18 lean (BMI: 18.8±1.9 kg/m²) adolescents (aged 12-18 years) performed a maximal cardiopulmonary exercise test on bike, with comparison of oxygen uptake (VO2), heart rate (HR), expiratory volume (VE), carbon dioxide output (VCO2), and cycling power output (W). RERpeak (1.09±0.06 vs. 1.14±0.06 in obese vs. lean adolescents, respectively) and RER slope (0.03±0.01 vs. 0.05±0.01 per 10% increase in VO2, in obese vs. lean adolescents, respectively) was significantly lower in obese adolescents, and independently related to BMI (Pexercise testing in this population.

Bicycling-related accidents and factors contributing to injury

Energy Technology Data Exchange (ETDEWEB)

Gonzalez Perez, L.M.; Wideberg, J.; Gonzalez Perez-Somarriba, B.

2016-07-01

Objective: This study was conducted to find the epidemiological characteristics of bicycling-related maxillofacial fractures in a defined population, and identify factors contributing to injury. Methodology: A prospective study was carried out involving patients presenting with maxillofacial fractures sustained in bicycling-related accidents. Results: Between 908 of all cycling accidents attending for medical treatment, 122 patients (13% of all cycling accidents) were admitted with facial fractures between 2007 and 2014. Male and female ratio was 2.6:1, and the mean age was 29.4 years (standard deviation: 12.8, range: 12-79 years). Causes of injury included collisions (63%) and accidental falls (37%). The fracture patterns seen were mandibular (49%), zygomatic (32%), orbital (13%), nasal (7%), maxillary (2%), and frontal (2%). Condylar fractures were the most common of the mandibular fractures (63%). The most frequently observed concomitant lesions were orthopedic injuries. Conclusions: Bicycling-related maxillofacial injuries are common and therefore important to identify in order to design a sustainable transport system and for units that provide assistance to traffic accident victims. Missed diagnosis or delayed treatment can lead to facial deformities and functional problems. Wearing protective helmets and the improvement of the helmets design is one aspect that would be of interest for the prevention of injuries. Keywords: Cycling; bicycle-related trauma; maxillofacial fractures; risk factors; helmets. (Author)

Effects of a meal on the hemorheologic responses to exercise in young males.

Science.gov (United States)

Bilski, Jan; Teległów, Aneta; Pokorski, Janusz; Nitecki, Jacek; Pokorska, Joanna; Nitecka, Ewa; Marchewka, Anna; Dąbrowski, Zbigniew; Marchewka, Jakub

2014-01-01

This study investigates the changes in hemorheologic parameters resulting from exercise followed by a standard meal. In twelve moderately active men a period of exercise on a bicycle ergometer for 30 min at 60% VO2max was followed by a test meal or by 30 min rest. Venous blood was sampled for further analysis at baseline, after exercise, and after the meal/rest period. The elongation index (EI) was reduced and a marked rise in plasma viscosity was observed after exercise. A significant decrease in half time of total aggregation (T 1/2) and a rise in aggregation index (AI) after exercise were observed; however, after the postexercise period these changes were reversed. The present study demonstrates that physical exercise causes several changes in blood rheology parameters, such as an increase of blood viscosity, a decrease in EI and an increase in AI, and a fall in the T 1/2 values. The meal eaten in the postexercise period caused a further reduction in EI values indicating higher red cell rigidity, but not in plasma viscosity or aggregations indices. Such alterations in hemorheologic parameters should not impair the function of the cardiovascular system in fit and healthy people but it could constitute a serious risk under various pathophysiological conditions.

Computer-assisted upper extremity training using interactive biking exercise (iBikE) platform.

Science.gov (United States)

Jeong, In Cheol; Finkelstein, Joseph

2012-01-01

Upper extremity exercise training has been shown to improve clinical outcomes in different chronic health conditions. Arm-operated bicycles are frequently used to facilitate upper extremity training however effective use of these devices at patient homes is hampered by lack of remote connectivity with clinical rehabilitation team, inability to monitor exercise progress in real time using simple graphical representation, and absence of an alert system which would prevent exertion levels exceeding those approved by the clinical rehabilitation team. We developed an interactive biking exercise (iBikE) platform aimed at addressing these limitations. The platform uses a miniature wireless 3-axis accelerometer mounted on a patient wrist that transmits the cycling acceleration data to a laptop. The laptop screen presents an exercise dashboard to the patient in real time allowing easy graphical visualization of exercise progress and presentation of exercise parameters in relation to prescribed targets. The iBikE platform is programmed to alert the patient when exercise intensity exceeds the levels recommended by the patient care provider. The iBikE platform has been tested in 7 healthy volunteers (age range: 26-50 years) and shown to reliably reflect exercise progress and to generate alerts at pre-setup levels. Implementation of remote connectivity with patient rehabilitation team is warranted for future extension and evaluation efforts.

Daily Bicycling in Older Adults May Be Effective to Reduce Fall Risks - A Case Control Study.

Science.gov (United States)

Batcir, Shani; Melzer, Itshak

2018-01-18

Older adults gain many health benefits from riding bicycles regularly. We aimed to explore whether older persons who ride bicycles regularly have better balance than controls. Balance control and voluntary stepping were assessed in 20 older adults aged 65 to 85 who live in an agricultural community village who regularly ride bicycles (BR), and 30 age- and gender-matched non-bicycle riders (NBR). Self-reported function and fear of fall were also assessed. Bicycle riders showed significantly better balance, faster voluntary stepping, and better self-reported advanced lower extremity function compared with NBR. The results might suggest that bicycling regularly preserves balance control and speed of voluntary stepping in older adults because bicycling might maintain specific balance coordination patterns. The results should be treated with caution since BR were older adults who selected an active life style (i.e., bicycling as well as living in an agricultural village) that may bias the results.

Evaluating the Interference of Bicycle Traffic on Vehicle Operation on Urban Streets with Bike Lanes

Directory of Open Access Journals (Sweden)

Ziyuan Pu

2017-01-01

Full Text Available Many urban streets are designed with on-street bike lanes to provide right-of-way for bicycle traffic. However, when bicycle flow is large, extensive passing maneuvers could occupy vehicle lanes and thus cause interferences to vehicle traffic. The primary objective of this study is to evaluate how bicycle traffic affects vehicle operation on urban streets with bike lanes. Data were collected on six street segments in Nanjing, China. The cumulative curves were constructed to extract traffic flow information including individual bicycle and vehicle speeds and aggregated traffic parameters such as flow and density. The results showed that as bicycle density on bike lanes continuously increases faster bicycles may run into vehicle lanes causing considerable reductions in vehicle speeds. A generalized linear model was estimated to predict the vehicle delay. Results showed that vehicle delay increases as bicycle flow and vehicle flow increase. Number of vehicle lanes and width of bike lane also have significant impact on vehicle delay. Findings of the study are helpful to regions around the world in bike infrastructure design in order to improve operations of both bicycles and vehicles.

Dynamic water exercise in individuals with late poliomyelitis.

Science.gov (United States)

Willén, C; Sunnerhagen, K S; Grimby, G

2001-01-01

To evaluate the specific effects of general dynamic water exercise in individuals with late effects of poliomyelitis. Before-after tests. A university hospital department. Twenty-eight individuals with late effects of polio, 15 assigned to the training group (TG) and 13 to the control group (CG). The TG completed a 40-minute general fitness training session in warm water twice weekly. Assessment instruments included the bicycle ergometer test, isokinetic muscle strength, a 30-meter walk indoors, Berg balance scale, a pain drawing, a visual analog scale, the Physical Activity Scale for the Elderly, and the Nottingham Health Profile (NHP). Peak load, peak work load, peak oxygen uptake, peak heart rate (HR), muscle function in knee extensors and flexors, and pain dimension of the NHP. The average training period was 5 months; compliance was 75% (range, 55-98). No negative effects were seen. The exercise did not influence the peak work load, peak oxygen uptake, or muscle function in knee extensors compared with the controls. However, a decreased HR at the same individual work load was seen, as well as a significantly lower distress in the dimension pain of the NHP. Qualitative aspects such as increased well-being, pain relief, and increased physical fitness were reported. A program of nonswimming dynamic exercises in heated water has a positive impact on individuals with late effects of polio, with a decreased HR at exercise, less pain, and a subjective positive experience. The program was well tolerated (no adverse effects were reported) and can be recommended for this group of individuals.

Physical exercise decreases the number of fetal cells in maternal blood

DEFF Research Database (Denmark)

Schlütter, Jacob Mørup; Kirkegaard, Ida; Christensen, Connie Britta

a bicycle for transport to the hospital as compared to transport by car (median 2 vs. 3 fcmb; P = 0.07). Even training of the pelvic floor within the preceding 3 hours seemed to slightly decrease fcmb (median 2 vs. 3 fcmb; P = 0.13). Conclusions Exercise within 24 hours reduces the number of fcmb...

Glucose clearance in aged trained skeletal muscle during maximal insulin with superimposed exercise

DEFF Research Database (Denmark)

Dela, Flemming; Mikines, K J; Larsen, J J

1999-01-01

Insulin and muscle contractions are major stimuli for glucose uptake in skeletal muscle and have in young healthy people been shown to be additive. We studied the effect of superimposed exercise during a maximal insulin stimulus on glucose uptake and clearance in trained (T) (1-legged bicycle tra...

Segmental wall-motion analysis in the right anterior oblique projection: comparison of exercise equilibrium radionuclide ventriculography and exercise contrast ventriculography

International Nuclear Information System (INIS)

Brady, T.J.; Thrall, J.H.; Keyes, J.W. Jr.; Brymer, J.F.; Walton, J.A.; Pitt, B.

1980-01-01

Thirty-nine patients with known or suspected coronary artery disease were studied at rest and during supine bicycle exercise with radionuclide and contrast left ventriculography. Analysis of regional wall motion was made by visual evaluation of the five standard 30 0 right anterior oblique (RAO) wall segments in the contrast images and the corresponding 10 0 RAO radionuclide segments. The radionuclide studies were evaluated independently by three observers using a five-point grading system. The interobserver wall-motion grading agreed completely in more than 80% of segments at rest and exercise, and agreed within one wall-motion grade in more than 95% of segments. The comparison of wall-motion grades between radionuclide and contrast ventriculograms showed complete agreement in 86% of segments at rest and in 78% during exercise, and agreement within one wall-motion grade in 97% of rest and 96% of exercise segments. Visual evaluation of 10 0 RAO rest and exercise radionuclide ventriculograms compares favorably with rest and exercise 30 0 RAO contrast ventriculograms and demonstrates satisfactory interobserver agreement

Physical exercise during encoding improves vocabulary learning in young female adults: a neuroendocrinological study.

Science.gov (United States)

Schmidt-Kassow, Maren; Deusser, Marie; Thiel, Christian; Otterbein, Sascha; Montag, Christian; Reuter, Martin; Banzer, Winfried; Kaiser, Jochen

2013-01-01

Acute physical activity has been repeatedly shown to improve various cognitive functions. However, there have been no investigations comparing the effects of exercise during verbal encoding versus exercise prior to encoding on long-term memory performance. In this current psychoneuroendocrinological study we aim to test whether light to moderate ergometric bicycling during vocabulary encoding enhances subsequent recall compared to encoding during physical rest and encoding after being physically active. Furthermore, we examined the kinetics of brain-derived neurotrophic factor (BDNF) in serum which has been previously shown to correlate with learning performance. We also controlled for the BDNF val66met polymorphism. We found better vocabulary test performance for subjects that were physically active during the encoding phase compared to sedentary subjects. Post-hoc tests revealed that this effect was particularly present in initially low performers. BDNF in serum and BDNF genotype failed to account for the current result. Our data indicates that light to moderate simultaneous physical activity during encoding, but not prior to encoding, is beneficial for subsequent recall of new items.

Chest Traumas due to Bicycle accident in Childhood

Directory of Open Access Journals (Sweden)

Ufuk Cobanoglu

2011-09-01

Full Text Available Aim:Childhood injuries are the leading cause of death in children and result in significant healthcare utilization. Trauma is the second most common cause of mortality in children aged 1-4 years and leading cause of death in children older than 4 years. Thoracic injury is the second most leading cause of death in traumatized children. Multisystemic injury is found in more than 50% of children with thoracic injuries most of which are secondary to blunt traumas. We planned this study to evaluate thorax trauma cases secondary to bicycle driving in childhood and to draw attention to the importance of the regulation of traffic rules, the education of bicycle drivers.Material and Methods:  A retrospective evaluation was performed in 17 pediatric patients admitted to the Department of Thoracic Surgery during 2006-2010 with a diagnosis of chest trauma due to bicycle driving. For every patient, a pediatric trauma score (PTS was calculated. Descriptive statistics were performed for PTS. Results; Eleven (64.70% cases were injured due to the tricycle accidents and six cases 6 (35.29% were injured due to the two-wheeled bicycle accidents. The most frequent thoracic pathologies included pulmonary contusion (41.2% and chest wall contusion (29.41%. Extrathoracic injuries were seen in 35.29%, the extremities (17.64% and abdomino pelvic (11.76% being the most commonly involved. Treatment consisted of symptomatic treatment in 12 patients (70.58%, tube thoracostomy in 2 patients (11.76%, and thoracotomy in 1 patient (5.9%. The morbidity was seen in 3 patients (17.64%. The mortality rate was 5.9% (n:1. The mean PTS of the cases who had additional system injuries were significantly worse than the cases who had isolated chest traumas Conclusions: The pediatric thorax has a greater cartilage content and incomplete ossification of the ribs. Due to the pliability of the pediatric rib cage and mediastinal mobility, significant intrathoracic injury may exist in the

Effect of sex differences on human MEF2 regulation during endurance exercise

DEFF Research Database (Denmark)

Vissing, Kristian; McGee, Sean L; Roepstorff, Carsten

2008-01-01

. The primary purpose of this study, therefore, was to investigate the protein signaling of MEF2 regulatory pathway components at rest and during 90 min of bicycling exercise at 60% Vo(2peak) in healthy, moderately trained men (n = 8) and women (n = 9) to elucidate the potential role of these proteins...

Predicting Public Bicycle Adoption Using the Technology Acceptance Model

Directory of Open Access Journals (Sweden)

Benjamin T. Hazen

2015-10-01

Full Text Available Bicycle sharing programs provide a sustainable mode of urban transportation. Although cities across the globe have developed these systems for their citizens and visitors, usage rates are not as high as anticipated. This research uses the technology acceptance model as the basis to understand one’s intention to adopt bicycle sharing programs. Using survey data derived from 421 participants in Beijing, China, the proposed covariance-based structural equation model consisting of perceived quality, perceived convenience, and perceived value is found to predict 50.5% of the variance in adoption intention. The findings of this research contribute to theory and practice in the burgeoning literature on public bicycle systems and sustainable urban transportation by offering a theoretical lens through which to consider system adoption, and providing information to practitioners as to what factors might contribute most to adoption.

The use of bicycle workstations to increase physical activity in secondary classrooms

Directory of Open Access Journals (Sweden)

Alicia Fedewa

2017-11-01

Full Text Available Background To date, the majority of interventions have implemented classroom-based physical activity (PA at the elementary level; however, there is both the potential and need to explore student outcomes at high-school level as well, given that very few studies have incorporated classroom-based PA interventions for adolescents. One exception has been the use of bicycle workstations within secondary classrooms. Using bicycle workstations in lieu of traditional chairs in a high school setting shows promise for enhancing adolescents’ physical activity during the school day. Participants and procedure The present study explored the effects of integrating bicycle workstations into a secondary classroom setting for four months in a sample of 115 adolescents using an A-B-A-B withdrawal design. The study took place in one Advanced Placement English classroom across five groups of students. Physical activity outcomes included average heart rate, and caloric expenditure. Behavioural outcomes included percentage of on-task/off-task behaviour and number of teacher prompts in redirecting off-task behaviour. Feasibility and acceptability data of using the bicycle workstations were also collected. Results Findings showed significant improvements in physical activity as measured by heart rate and caloric expenditure, although heart rate percentage remained in the low intensity range when students were on the bicycle workstations. No effects were found on students’ on-task behaviour when using the bicycle workstations. Overall, students found the bikes acceptable to use but noted disadvantages of them as well. Conclusions Using bicycle workstations in high-school settings appears promising for enhancing low-intensity physical activity among adolescents. The limitations of the present study and implications for physical activity interventions in secondary schools are discussed.

Circulatory response evoked by a 3 s bout of dynamic leg exercise in humans

NARCIS (Netherlands)

Wieling, W.; Harms, M. P.; ten Harkel, A. D.; van Lieshout, J. J.; Sprangers, R. L.

1996-01-01

1. The mechanisms underlying the pronounced transient fall in arterial blood pressure evoked by a 3 s bout of bicycle exercise were investigated in twenty healthy young adults and four patients with hypoadrenergic orthostatic hypotension. 2. In healthy subjects a 3 s bout of upright cycling induced

Validity of the Eating Attitude Test among Exercisers.

Science.gov (United States)

Lane, Helen J; Lane, Andrew M; Matheson, Hilary

2004-12-01

Theory testing and construct measurement are inextricably linked. To date, no published research has looked at the factorial validity of an existing eating attitude inventory for use with exercisers. The Eating Attitude Test (EAT) is a 26-item measure that yields a single index of disordered eating attitudes. The original factor analysis showed three interrelated factors: Dieting behavior (13-items), oral control (7-items), and bulimia nervosa-food preoccupation (6-items). The primary purpose of the study was to examine the factorial validity of the EAT among a sample of exercisers. The second purpose was to investigate relationships between eating attitudes scores and selected psychological constructs. In stage one, 598 regular exercisers completed the EAT. Confirmatory factor analysis (CFA) was used to test the single-factor, a three-factor model, and a four-factor model, which distinguished bulimia from food pre-occupation. CFA of the single-factor model (RCFI = 0.66, RMSEA = 0.10), the three-factor-model (RCFI = 0.74; RMSEA = 0.09) showed poor model fit. There was marginal fit for the 4-factor model (RCFI = 0.91, RMSEA = 0.06). Results indicated five-items showed poor factor loadings. After these 5-items were discarded, the three models were re-analyzed. CFA results indicated that the single-factor model (RCFI = 0.76, RMSEA = 0.10) and three-factor model (RCFI = 0.82, RMSEA = 0.08) showed poor fit. CFA results for the four-factor model showed acceptable fit indices (RCFI = 0.98, RMSEA = 0.06). Stage two explored relationships between EAT scores, mood, self-esteem, and motivational indices toward exercise in terms of self-determination, enjoyment and competence. Correlation results indicated that depressed mood scores positively correlated with bulimia and dieting scores. Further, dieting was inversely related with self-determination toward exercising. Collectively, findings suggest that a 21-item four-factor model shows promising validity coefficients among

The Effect of Pretest Exercise on Baseline Computerized Neurocognitive Test Scores.

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Pawlukiewicz, Alec; Yengo-Kahn, Aaron M; Solomon, Gary

2017-10-01

Baseline neurocognitive assessment plays a critical role in return-to-play decision making following sport-related concussions. Prior studies have assessed the effect of a variety of modifying factors on neurocognitive baseline test scores. However, relatively little investigation has been conducted regarding the effect of pretest exercise on baseline testing. The aim of our investigation was to determine the effect of pretest exercise on baseline Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores in adolescent and young adult athletes. We hypothesized that athletes undergoing self-reported strenuous exercise within 3 hours of baseline testing would perform more poorly on neurocognitive metrics and would report a greater number of symptoms than those who had not completed such exercise. Cross-sectional study; Level of evidence, 3. The ImPACT records of 18,245 adolescent and young adult athletes were retrospectively analyzed. After application of inclusion and exclusion criteria, participants were dichotomized into groups based on a positive (n = 664) or negative (n = 6609) self-reported history of strenuous exercise within 3 hours of the baseline test. Participants with a positive history of exercise were then randomly matched, based on age, sex, education level, concussion history, and hours of sleep prior to testing, on a 1:2 basis with individuals who had reported no pretest exercise. The baseline ImPACT composite scores of the 2 groups were then compared. Significant differences were observed for the ImPACT composite scores of verbal memory, visual memory, reaction time, and impulse control as well as for the total symptom score. No significant between-group difference was detected for the visual motor composite score. Furthermore, pretest exercise was associated with a significant increase in the overall frequency of invalid test results. Our results suggest a statistically significant difference in ImPACT composite scores between

Neuropsychological benefits of stationary bike exercise and a cybercycle exergame for older adults with diabetes: an exploratory analysis.

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Anderson-Hanley, Cay; Arciero, Paul J; Westen, Sarah C; Nimon, Joseph; Zimmerman, Earl

2012-07-01

This quasi-experimental exploratory study investigated neuropsychological effects of exercise among older adults with diabetes mellitus (DM) compared with adults without diabetes (non-DM), and it examined the feasibility of using a stationary bike exergame as a form of exercise for older adults with and without diabetes. It is a secondary analysis that uses a small dataset from a larger randomized clinical trial (RCT) called the Cybercycle Study, which compared cognitive and physiological effects of traditional stationary cycling versus cybercycling. In the RCT and the secondary analysis, older adults living in eight independent living retirement facilities in the state of New York were enrolled in the study and assigned to exercise five times per week for 45 min per session (two times per week was considered acceptable for retention in the study) by using a stationary bicycle over the course of 3 months. They were randomly assigned to use either a standard stationary bicycle or a "cybercycle" with a video screen that displayed virtual terrains, virtual tours, and racing games with virtual competitors. For this secondary analysis, participants in the RCT who had type 2 DM (n = 10) were compared with age-matched non-DM exercisers (n = 10). The relationship between exercise and executive function (i.e., Color Trials 2, Digit Span Backwards, and Stroop C tests) was examined for DM and non-DM patients. Older adults with and without diabetes were able to use cybercycles successfully and complete the study, so the feasibility of this form of exercise for this population was supported. However, in contrast with the larger RCT, this small subset did not demonstrate statistically significant differences in executive function between the participants who used cybercycles and those who used stationary bikes with no games or virtual content on a video screen. Therefore, the study combined the two groups and called them "exercisers" and compared cognitive outcomes for DM versus

Revealed Preference Methods for Studying Bicycle Route Choice—A Systematic Review

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Ray Pritchard

2018-03-01

Full Text Available One fundamental aspect of promoting utilitarian bicycle use involves making modifications to the built environment to improve the safety, efficiency and enjoyability of cycling. Revealed preference data on bicycle route choice can assist greatly in understanding the actual behaviour of a highly heterogeneous group of users, which in turn assists the prioritisation of infrastructure or other built environment initiatives. This systematic review seeks to compare the relative strengths and weaknesses of the empirical approaches for evaluating whole journey route choices of bicyclists. Two electronic databases were systematically searched for a selection of keywords pertaining to bicycle and route choice. In total seven families of methods are identified: GPS devices, smartphone applications, crowdsourcing, participant-recalled routes, accompanied journeys, egocentric cameras and virtual reality. The study illustrates a trade-off in the quality of data obtainable and the average number of participants. Future additional methods could include dockless bikeshare, multiple camera solutions using computer vision and immersive bicycle simulator environments.

EFFECT OF HIGH & LOW INTENSITIES OF AEROBIC EXERCISE ON PHYSICAL FITNESS INDEX

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Madhusudhan

2015-06-01

Full Text Available BACKGROUND: Aerobic exercise reduces body fat and improves weight control, increases HDL&Vo2 max. Also improves PFI (physical fitness index which is defined as ability to carry out daily tasks with vigour and alertness without undue fatigue. Though aerobic exercise is found to improve physical fitness, the relative merits of different intensities of aerobi c exercise in improving physical fitness is still uncertain. AIM: The present study was conducted to know the Effect of High & low intensity aerobic training on physical fitness index. MATERIALS & METHODS : 80 sedentary men (18 - 40 years were randomized in to 2 equal groups (High Intensity & low intensity group . The High [80% HR max] & Low intensity [50 % HR max] groups underwent aerobic exercise training using Bicycle ergo meter (COSCO at 900kpm & 540kpm, for 15mins/day & 30mins/day respectively, 5days a week, for a period of 14weeks. Physical fitness index of each subject was recorded by Modified Harvard step test before & after intervention. RESULTS : After 14 weeks of aerobic training both the exercise groups had improvement in PFI, but high intensity gr oup had a significant (p<0.05 improvement in PFI (97.18 - 101.14 than low intensity group (98.12 - 100.6. CONCLUSION : High intensity aerobic exercise is effective in improving physical fitness.

Investigation of Bicycle Travel Time Estimation Using Bluetooth Sensors for Low Sampling Rates

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Zhenyu Mei

2014-10-01

Full Text Available Filtering the data for bicycle travel time using Bluetooth sensors is crucial to the estimation of link travel times on a corridor. The current paper describes an adaptive filtering algorithm for estimating bicycle travel times using Bluetooth data, with consideration of low sampling rates. The data for bicycle travel time using Bluetooth sensors has two characteristics. First, the bicycle flow contains stable and unstable conditions. Second, the collected data have low sampling rates (less than 1%. To avoid erroneous inference, filters are introduced to “purify” multiple time series. The valid data are identified within a dynamically varying validity window with the use of a robust data-filtering procedure. The size of the validity window varies based on the number of preceding sampling intervals without a Bluetooth record. Applications of the proposed algorithm to the dataset from Genshan East Road and Moganshan Road in Hangzhou demonstrate its ability to track typical variations in bicycle travel time efficiently, while suppressing high frequency noise signals.

Interventions in Bicycle Infrastructure, Lessons from Dutch and Danish Cases

DEFF Research Database (Denmark)

van Goeverden, K.; Nielsen, Thomas Alexander Sick; Harder, Henrik

2015-01-01

of interventions in bicycle infrastructure on travel choices, safety, design appreciation, and other factors. These clarify under which conditions certain measures are effective or not and inform about the effectiveness of improving a single route versus upgrading a whole network. The information from the studies...... to be still generally valid. In addition to studies that traditionally focus on dedicated bicycle infrastructure, two cases of shared space are discussed, a rather new type of intervention that assumes mixed use of infrastructure. One case is from Denmark, the other from the Netherlands. The paper will so...... uncover the valuable results of the possibly largest evaluations of interventions in bicycle infrastructure ever made, verify these by examining more recent studies, and contribute to the discussion of shared space....

The role of exercise testing in heart failure.

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Swedberg, K; Gundersen, T

1993-01-01

The objectives of exercise testing in congestive heart failure (CHF) may be summarized as follows: (a) detect impaired cardiac performance, (b) grade severity of cardiac failure and classify functional capability, and (c) assess effects of interventions. Several different methods are available to make these assessments, and we have to ask ourselves how well exercise testing achieves these objectives. It has to be kept in mind that the power generated by the exercising muscles is dependent on the oxygen delivery to the skeletal muscles. Oxygen uptake is the result of an integrated performance of the lungs, heart, and peripheral circulation. In patients, as well as in normal subjects, oxygen uptake is related to hemodynamic indices such as cardiac output, stroke volume, or exercise duration when a stepwise regulated maximal exercise protocol is used. However, there are major differences in the concept of a true maximum in normal subjects versus heart failure patients. Fit-normal subjects will achieve a real maximal oxygen uptake, whereas patients may stop testing before a maximum is reached because of symptoms such as dyspnea or leg fatigue. Therefore, it is better if the actual oxygen uptake can be measured. "Peak" rather than true maximal oxygen uptake has been suggested for the classification of the severity of heart failure. Peripheral factors modify the cardiac output through such factors as vascular resistance, organ function, and hormonal release. Maximal exercise will stress the cardiovascular system to a point where the weakest chain will impose a limiting effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Transient left ventricular apical ballooning and exercise induced hypertension during treadmill exercise testing: is there a common hypersympathetic mechanism?

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Oh Jae K

2008-07-01

Full Text Available Abstract Objective To describe two cases of Takotsubo like myocardial contractile pattern during exercise stress test secondary to hypertensive response. Background Treadmill exercise testing is known to cause sympathetic stimulation, leading to increased levels of catecholamine, resulting in alteration in vascular tone. Hypertensive response during exercise testing can cause abnormal consequences, resulting in false positive results. Cases We present the cases of two patients experiencing apical and basal akinesis during exercise stress echocardiography, in whom normal wall motion response was observed on subsequent pharmacologic stress testing. The first patient developed transient left ventricular (LV apical akinesis during exercise stress echocardiography. Due to high suspicion that this abnormality might be secondary to hypertensive response, pharmacologic stress testing was performed after three days, which was completely normal and showed no such wall motion abnormality. Qualitative assessment of myocardial perfusion using contrast was also performed, which showed good myocardial blood flow, indicating low probability for significant obstructive coronary artery disease. The second patient developed LV basal akinesis as a result of hypertensive response during exercise testing. Coronary angiogram was not performed in either patient due to low suspicion for coronary artery disease, and subsequently negative stress studies. Results Transient stress induced cardiomyopathy can develop secondary to hypertensive response during exercise stress testing. Conclusion These cases provide supporting evidence to the hyper-sympathetic theory of left ventricular ballooning syndrome.

Pediatric Exercise Testing: Value and Implications of Peak Oxygen Uptake

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Paolo T. Pianosi

2017-01-01

Full Text Available Peak oxygen uptake (peak V ˙ O 2 measured by clinical exercise testing is the benchmark for aerobic fitness. Aerobic fitness, estimated from maximal treadmill exercise, is a predictor of mortality in adults. Peak V ˙ O 2 was shown to predict longevity in patients aged 7–35 years with cystic fibrosis over 25 years ago. A surge of exercise studies in young adults with congenital heart disease over the past decade has revealed significant prognostic information. Three years ago, the first clinical trial in children with pulmonary arterial hypertension used peak V ˙ O 2 as an endpoint that likewise delivered clinically relevant data. Cardiopulmonary exercise testing provides clinicians with biomarkers and clinical outcomes, and researchers with novel insights into fundamental biological mechanisms reflecting an integrated physiological response hidden at rest. Momentum from these pioneering observations in multiple disease states should impel clinicians to employ similar methods in other patient populations; e.g., sickle cell disease. Advances in pediatric exercise science will elucidate new pathways that may identify novel biomarkers. Our initial aim of this essay is to highlight the clinical relevance of exercise testing to determine peak V ˙ O 2 , and thereby convince clinicians of its merit, stimulating future clinical investigators to broaden the application of exercise testing in pediatrics.

Low-stress bicycling and network connectivity.

Science.gov (United States)

2012-05-01

For a bicycling network to attract the widest possible segment of the population, its most fundamental attribute should be low-stress connectivity, that is, providing routes between peoples origins and destinations that do not require cyclists to ...

The unexpected stable market share of the bicycle in The Netherlands

NARCIS (Netherlands)

Van Goeverden, C.D.; Van Arem, B.; Godefrooij, T.

2013-01-01

In the Netherlands, the share of the bicycle as the main mode in all person trips has been highly constant in the past three decades (about 27%). A constant share is remarkable because a number of developments in this period were unfavourable for bicycle use, like ageing of the population, growing

Bicycle Trains, Cycling, and Physical Activity: A Pilot Cluster RCT.

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Mendoza, Jason A; Haaland, Wren; Jacobs, Maya; Abbey-Lambertz, Mark; Miller, Josh; Salls, Deb; Todd, Winifred; Madding, Rachel; Ellis, Katherine; Kerr, Jacqueline

2017-10-01

Increasing children's cycling to school and physical activity are national health goals. The objective was to conduct an RCT of a bicycle train program to assess impact on students' school travel mode and moderate-to-vigorous physical activity (MVPA). Pilot cluster RCT with randomization at the school level and N=54 participants. Fourth-fifth graders from four public schools serving low-income families in Seattle, WA in 2014 with analyses in 2015-2016. All participants were provided and fitted with bicycles, safety equipment (helmets, locks, and lights), and a 2- to 3-hour bicycle safety course. The intervention was a bicycle train offered daily (i.e., students volunteered to cycle with study staff to and from school). Time 1 assessments occurred prior to randomization. Time 2 assessments occurred after 3-5 weeks of the intervention (i.e., during Weeks 4-6 of the intervention period). The primary outcome was the percentage of daily commutes to school by cycling measured by validated survey. MVPA, measured by accelerometry and GPS units and processed by machine learning algorithms, was a secondary outcome. For two separate adjusted repeated measures linear mixed effects models in which students (N=54) were nested within schools (N=4), intervention participants had: (1) an absolute increase in mean percentage of daily commutes by cycling of 44.9%, (95% CI=26.8, 63.0) and (2) an increase in mean MVPA of 21.6 minutes/day, (95% CI=8.7, 34.6) from Time 1 to Time 2 compared with controls. A pilot bicycle train intervention increased cycling to school and daily MVPA in the short term among diverse, inner-city elementary school students. The bicycle train intervention appears promising and warrants further experimental trials among large, diverse samples with longer follow-up. This study is registered at www.clinicaltrials.gov NCT02006186. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Altered Energetics of Exercise Explain Risk of Rhabdomyolysis in Very Long-Chain Acyl-CoA Dehydrogenase Deficiency

NARCIS (Netherlands)

Diekman, E. F.; Visser, G.; Schmitz, J. P. J.; Nievelstein, R. A. J.; de Sain-van der Velden, M.; Wardrop, M.; van der Pol, W. L.; Houten, S. M.; van Riel, N. A. W.; Takken, T.; Jeneson, J. A. L.

2016-01-01

Rhabdomyolysis is common in very long-chain acyl-CoA dehydrogenase deficiency (VLCADD) and other metabolic myopathies, but its pathogenic basis is poorly understood. Here, we show that prolonged bicycling exercise against a standardized moderate workload in VLCADD patients is associated with

Effects of a Meal on the Hemorheologic Responses to Exercise in Young Males

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Jan Bilski

2014-01-01

Full Text Available Aim. This study investigates the changes in hemorheologic parameters resulting from exercise followed by a standard meal. Methods. In twelve moderately active men a period of exercise on a bicycle ergometer for 30 min at 60% VO2max was followed by a test meal or by 30 min rest. Venous blood was sampled for further analysis at baseline, after exercise, and after the meal/rest period. Results. The elongation index (EI was reduced and a marked rise in plasma viscosity was observed after exercise. A significant decrease in half time of total aggregation (T1/2 and a rise in aggregation index (AI after exercise were observed; however, after the postexercise period these changes were reversed. Conclusion. The present study demonstrates that physical exercise causes several changes in blood rheology parameters, such as an increase of blood viscosity, a decrease in EI and an increase in AI, and a fall in the T1/2 values. The meal eaten in the postexercise period caused a further reduction in EI values indicating higher red cell rigidity, but not in plasma viscosity or aggregations indices. Such alterations in hemorheologic parameters should not impair the function of the cardiovascular system in fit and healthy people but it could constitute a serious risk under various pathophysiological conditions.

Variable Accuracy of Wearable Heart Rate Monitors during Aerobic Exercise.

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Gillinov, Stephen; Etiwy, Muhammad; Wang, Robert; Blackburn, Gordon; Phelan, Dermot; Gillinov, A Marc; Houghtaling, Penny; Javadikasgari, Hoda; Desai, Milind Y

2017-08-01

Athletes and members of the public increasingly rely on wearable HR monitors to guide physical activity and training. The accuracy of newer, optically based monitors is unconfirmed. We sought to assess the accuracy of five optically based HR monitors during various types of aerobic exercise. Fifty healthy adult volunteers (mean ± SD age = 38 ± 12 yr, 54% female) completed exercise protocols on a treadmill, a stationary bicycle, and an elliptical trainer (±arm movement). Each participant underwent HR monitoring with an electrocardiogaphic chest strap monitor (Polar H7), forearm monitor (Scosche Rhythm+), and two randomly assigned wrist-worn HR monitors (Apple Watch, Fitbit Blaze, Garmin Forerunner 235, and TomTom Spark Cardio), one on each wrist. For each exercise type, HR was recorded at rest, light, moderate, and vigorous intensity. Agreement between HR measurements was assessed using Lin's concordance correlation coefficient (rc). Across all exercise conditions, the chest strap monitor (Polar H7) had the best agreement with ECG (rc = 0.996) followed by the Apple Watch (rc = 0.92), the TomTom Spark (rc = 0.83), and the Garmin Forerunner (rc = 0.81). Scosche Rhythm+ and Fitbit Blaze were less accurate (rc = 0.75 and rc = 0.67, respectively). On treadmill, all devices performed well (rc = 0.88-0.93) except the Fitbit Blaze (rc = 0.76). While bicycling, only the Garmin, Apple Watch, and Scosche Rhythm+ had acceptable agreement (rc > 0.80). On the elliptical trainer without arm levers, only the Apple Watch was accurate (rc = 0.94). None of the devices was accurate during elliptical trainer use with arm levers (all rc < 0.80). The accuracy of wearable, optically based HR monitors varies with exercise type and is greatest on the treadmill and lowest on elliptical trainer. Electrode-containing chest monitors should be used when accurate HR measurement is imperative.

Repeatability and responsiveness of exercise tests in pulmonary arterial hypertension.

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Mainguy, Vincent; Malenfant, Simon; Neyron, Anne-Sophie; Bonnet, Sébastien; Maltais, François; Saey, Didier; Provencher, Steeve

2013-08-01

Exercise tolerance in pulmonary arterial hypertension (PAH) is most commonly assessed by the 6-min walk test (6MWT). Whether endurance exercise tests are more responsive than the 6MWT remains unknown. 20 stable PAH patients (mean±sd age 53±15 years and mean pulmonary arterial pressure 44±16 mmHg) already on PAH monotherapy completed the 6MWT, the endurance shuttle walk test (ESWT) and the cycle endurance test (CET) before and after the addition of sildenafil citrate 20 mg three times daily or placebo for 28 days in a randomised double-blind crossover setting. Pre- or post-placebo tests were used to assess repeatability of each exercise test, whereas pre- or post-sildenafil citrate tests were used to assess their responsiveness. Sildenafil citrate led to placebo-corrected changes in exercise capacity of 18±25 m (p = 0.02), 58±235 s (p = 0.58) and 29±77 s (p = 0.09) for the 6MWT, the ESWT and the CET, respectively. The 6MWT was associated with a lower coefficient of variation between repeated measures (3% versus 18% versus 13%), resulting in a higher standardised response mean compared with endurance tests (0.72, 0.25 and 0.38 for the 6MWT, the ESWT and the CET, respectively). The 6MWT had the best ability to capture changes in exercise capacity when sildenafil citrate was combined with patients' baseline monotherapy, supporting its use as an outcome measure in PAH.

Driver braking behavior analysis to improve autonomous emergency braking systems in typical Chinese vehicle-bicycle conflicts.

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Duan, Jingliang; Li, Renjie; Hou, Lian; Wang, Wenjun; Li, Guofa; Li, Shengbo Eben; Cheng, Bo; Gao, Hongbo

2017-11-01

Bicycling is one of the fundamental modes of transportation especially in developing countries. Because of the lack of effective protection for bicyclists, vehicle-bicycle (V-B) accident has become a primary contributor to traffic fatalities. Although AEB (Autonomous Emergency Braking) systems have been developed to avoid or mitigate collisions, they need to be further adapted in various conflict situations. This paper analyzes the driver's braking behavior in typical V-B conflicts of China to improve the performance of Bicyclist-AEB systems. Naturalistic driving data were collected, from which the top three scenarios of V-B accidents in China were extracted, including SCR (a bicycle crossing the road from right while a car is driving straight), SCL (a bicycle crossing the road from left while a car is driving straight) and SSR (a bicycle swerving in front of the car from right while a car is driving straight). For safety and data reliability, a driving simulator was employed to reconstruct these three scenarios and some 25 licensed drivers were recruited for braking behavior analysis. Results revealed that driver's braking behavior was significantly influenced by V-B conflict types. Pre-decelerating behaviors were found in SCL and SSR conflicts, whereas in SCR the subjects were less vigilant. The brake reaction time and brake severity in lateral V-B conflicts (SCR and SCL) was shorter and higher than that in longitudinal conflicts (SSR). The findings improve their applications in the Bicyclist-AEB and test protocol enactment to enhance the performance of Bicyclist-AEB systems in mixed traffic situations especially for developing countries. Copyright © 2017 Elsevier Ltd. All rights reserved.

DEVELOPMENT OF AN ELECTRIC BICYCLE FOR A SHARING SYSTEM IN PRAGUE

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William Deleenheer

2017-12-01

Full Text Available By means of a development of an e-bike sharing system the Electromobility Project wants to provide an alternative way of comfortable transportation for students and staff of the CTU, primarily to commute between different campuses. The research for this project contains at least three different fields of study, namely electric vehicle and docking station development, intelligent transport systems and management and economics of transportation and telecommunication. After briefly stating general requirements for the sharing system, this paper focuses on the development of the electric bicycle. First an ideal bike design is defined. Then necessary motor power and battery capacity are calculated by estimating characteristics of cycling in Prague. A prototype was developed by converting a normal bicycle to an electric bicycle. Being equipped with devices for e-bike monitoring, controlling and data recording for a post trip analysis, this prototype is also intended to have an educational value for future students in the project. Results consist of an electrical bicycle configuration that matches the requirements and a sketch of an ideal e-bike for this project.

Utility of the exercise electrocardiogram testing in sudden cardiac death risk stratification.

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Refaat, Marwan M; Hotait, Mostafa; Tseng, Zian H

2014-07-01

Sudden cardiac death (SCD) remains a major public health problem. Current established criteria identifying those at risk of sudden arrhythmic death, and likely to benefit from implantable cardioverter defibrillators (ICDs), are neither sensitive nor specific. Exercise electrocardiogram (ECG) testing was traditionally used for information concerning patients' symptoms, exercise capacity, cardiovascular function, myocardial ischemia detection, and hemodynamic responses during activity in patients with hypertrophic cardiomyopathy. We conducted a systematic review of MEDLINE on the utility of exercise ECG testing in SCD risk stratification. Exercise testing can unmask suspected primary electrical diseases in certain patients (catecholaminergic polymorphic ventricular tachycardia or concealed long QT syndrome) and can be effectively utilized to risk stratify patients at an increased (such as early repolarization syndrome and Brugada syndrome) or decreased risk of SCD, such as the loss of preexcitation on exercise testing in asymptomatic Wolff-Parkinson-White syndrome. Exercise ECG testing helps in SCD risk stratification in patients with and without arrhythmogenic hereditary syndromes. © 2014 Wiley Periodicals, Inc.

Bicycle Safety: Sport Education Style

Science.gov (United States)

Sinelnikov, Oleg A.; Hastie, Peter A.; Cole, Amy; Schneulle, Deanna

2005-01-01

Although the benefits of regular physical activity are well-documented and very well known, Americans are still becoming more sedentary and obese. As some experts envision the potential of nonmotorized transport in the future, especially in urban settings, it is not surprising that diverse groups view walking and bicycling as a solution to an…

Skeletal muscle substrate metabolism during exercise: methodological considerations

DEFF Research Database (Denmark)

Van Hall, Gerrit; González-Alonso, J; Sacchetti, M

1999-01-01

and the respiratory exchange ratio. However, if the aim is to quantify limb or muscle metabolism, invasive measurements have to be carried out, such as the determination of blood flow, arterio-venous (a-v) difference measurements for O2 and relevant substrates, and biopsies of the active muscle. As many substrates...... substrates. There are several methodological concerns to be aware of when studying the metabolic response to exercise in human subjects. These concerns include: (1) the muscle mass involved in the exercise is largely unknown (bicycle or treadmill). Moreover, whether the muscle sample obtained from a limb......; (3) the use of net limb glycerol release to estimate lipolysis is probably not valid (triacylglycerol utilization by muscle), since glycerol can be metabolized in skeletal muscle; (4) the precision of blood-borne substrate concentrations during exercise measured by a-v difference is hampered since...

Improvement of Freezing of Gait in Patients with Parkinson's Disease by Imagining Bicycling

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Akio Kikuchi

2014-03-01

Full Text Available Freezing of gait (FOG is one of the factors that reduce the quality of life in patients with Parkinson's disease (PD. Imagining bicycling before gait start provided improvement in FOG in 2 PD patients. Imagining and mimicking bicycling after the initiation of gait allowed the rhythmic gait to continue without interruption. We suggest that imagining and mimicking bicycling, which are nonexternal cues, could serve as a helpful therapeutic approach for the intractable freezing and interruption of gait of PD patients.

Effects of Acute Endurance Exercise on Plasma Protein Profiles of Endurance-Trained and Untrained Individuals over Time

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Marius Schild

2016-01-01

Full Text Available Acute physical exercise and repeated exercise stimuli affect whole-body metabolic and immunologic homeostasis. The aim of this study was to determine plasma protein profiles of trained (EET, n=19 and untrained (SED, n=17 individuals at rest and in response to an acute bout of endurance exercise. Participants completed a bicycle exercise test at an intensity corresponding to 80% of their VO2max. Plasma samples were taken before, directly after, and three hours after exercise and analyzed using multiplex immunoassays. Seventy-eight plasma variables were included in the final analysis. Twenty-nine variables displayed significant acute exercise effects in both groups. Seven proteins differed between groups, without being affected by acute exercise. Among these A2Macro and IL-5 were higher in EET individuals while leptin showed elevated levels in SED individuals. Fifteen variables revealed group and time differences with elevated levels for IL-3, IL-7, IL-10, and TNFR2 in EET individuals. An interaction effect could be observed for nine variables including IL-6, MMP-2, MMP-3, and muscle damage markers. The proteins that differ between groups indicate a long-term exercise effect on plasma protein concentrations. These findings might be of importance in the development of exercise-based strategies in the prevention and therapy of chronic metabolic and inflammatory diseases and for training monitoring.

Determining the Optimal Layout Design for Public Bicycle System within the Attractive Scope of a Metro Station

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Jingxu Chen

2015-01-01

Full Text Available Public bicycle acts as a seamless feeder mode in combination with the citywide public transit, as well as a competitor for the inner-city short trips. The primary objective of this study is to address the layout planning of public bicycle system within the attracted scope of a metro station. Based on the land use function, population, and bicycle mode share, bicycle rental stations are divided into three types, namely, the metro station, district station, and resident station, and later the quantity of bicycle facilities in each rental station is estimated. Then, the service stations are selected from these bicycle rental stations to provide the service of periodical bicycle redistribution. An improved immune algorithm is proposed to determine the number and locations of service stations and the optimal route options for the implement of redistributing strategy. Finally, a case study of Nanjing Tianyin Road metro station is conducted to illustrate the proposed model and clarify some of its implementation details.

Energy metabolism of medium-chain triglycerides versus carbohydrates during exercise.

Science.gov (United States)

Décombaz, J; Arnaud, M J; Milon, H; Moesch, H; Philippossian, G; Thélin, A L; Howald, H

1983-01-01

Medium-chain triglycerides (MCT) are known to be rapidly digested and oxidized. Their potential value as a source of dietary energy during exercise was compared with that of maltodextrins (MD). Twelve subjects exercised for 1 h on a bicycle ergometer (60% VO2 max), 1 h after the test meal (1MJ). The metabolism of MCT was followed using 1-13C-octanoate (Oc) as tracer and U-13C-glucose (G) was added to the 13C-naturally enriched MD. After MCT ingestion no insulin peak was observed with some accumulation of ketone bodies (KB), blood levels not exceeding 1 mM. Total losses of KB during exercise in urine, sweat and as breath acetone were small (less than 0.2 mmol X h-1). Hence, the influence of KB loss and storage on gas exchange data was negligible. The partition of fat and carbohydrate utilization during exercise as obtained by indirect calorimetry was practically the same after the MCT and the CHO meals. Oxidation over the 2-h period was 30% of dose for Oc and 45% for G. Glycogen decrements in the Vastus lateralis muscle were equal. It appears that with normal carbohydrate stores, a single meal of MCT or CHO did not alter the contribution of carbohydrates during 1 h of high submaximal exercise. The moderate ketonemia after MCT, despite substantial oxidation of this fat, led to no difference in muscle glycogen sparing between the diets.

Effects of Pressure Support Ventilation May Be Lost at High Exercise Intensities in People with COPD.

Science.gov (United States)

Anekwe, David; de Marchie, Michel; Spahija, Jadranka

2017-06-01

Pressure support ventilation (PSV) may be used for exercise training in chronic obstructive pulmonary disease (COPD), but its acute effect on maximum exercise capacity is not fully known. The objective of this study was to evaluate the effect of 10 cm H 2 O PSV and a fixed PSV level titrated to patient comfort at rest on maximum exercise workload (WLmax), breathing pattern and metabolic parameters during a symptom-limited incremental bicycle test in individuals with COPD. Eleven individuals with COPD (forced expiratory volume in one second: 49 ± 16%; age: 64 ± 7 years) performed three exercise tests: without a ventilator, with 10 cm H 2 O of PSV and with a fixed level titrated to comfort at rest, using a SERVO-i ventilator. Tests were performed in randomized order and at least 48 hours apart. The WLmax, breathing pattern, metabolic parameters, and mouth pressure (Pmo) were compared using repeated measures analysis of variance. Mean PSV during titration was 8.2 ± 4.5 cm H 2 O. There was no difference in the WLmax achieved during the three tests. At rest, PSV increased the tidal volume, minute ventilation, and mean inspiratory flow with a lower end-tidal CO 2 ; this was not sustained at peak exercise. Pmo decreased progressively (decreased unloading) with PSV at workloads close to peak, suggesting the ventilator was unable to keep up with the increased ventilatory demand at high workloads. In conclusion, with a Servo-i ventilator, 10 cm H 2 O of PSV and a fixed level of PSV established by titration to comfort at rest, is ineffective for the purpose of achieving higher exercise workloads as the acute physiological effects may not be sustained at peak exercise.

Exercise Testing Reveals Everyday Physical Challenges of Bariatric Surgery Candidates.

Science.gov (United States)

Creel, David B; Schuh, Leslie M; Newton, Robert L; Stote, Joseph J; Cacucci, Brenda M

2017-12-01

Few studies have quantified cardiorespiratory fitness among individuals seeking bariatric surgery. Treadmill testing allows researchers to determine exercise capacity through metabolic equivalents. These findings can assist clinicians in understanding patients' capabilities to carry out various activities of daily living. The purpose of this study was to determine exercise tolerance and the variables associated with fitness, among individuals seeking bariatric surgery. Bariatric surgery candidates completed submaximal treadmill testing and provided ratings of perceived exertion. Each participant also completed questionnaires related to history of exercise, mood, and perceived barriers/benefits of exercise. Over half of participants reported that exercise was "hard to very hard" before reaching 70% of heart rate reserve, and one-third of participants reported that exercise was "moderately hard" at less than 3 metabolic equivalents (light activity). Body mass index and age accounted for the majority of the variance in exercise tolerance, but athletic history, employment status, and perceived health benefits also contributed. Perceived benefit scores were higher than barrier scores. Categories commonly used to describe moderate-intensity exercise (3-6 metabolic equivalents) do not coincide with perceptions of intensity among many bariatric surgery candidates, especially those with a body mass index of 50 or more.

EP BICYCLE POOL - VIGNETTES 2002

CERN Multimedia

EP-SMI Help Desk

2002-01-01

The vignettes (insurance certificates) for 2002 become obligatory from 1 June. If you have a bicycle from the EP Pool, please bring it to the EP-SMI Help Desk (Building 124) on any working day up to 31 May between 8h.30 - 12h.00 or 13h.30 - 17h.30. EP-SMI Help Desk

VALIDITY OF THE EATING ATTITUDE TEST AMONG EXERCISERS

Directory of Open Access Journals (Sweden)

Hilary Matheson

2004-12-01

Full Text Available Theory testing and construct measurement are inextricably linked. To date, no published research has looked at the factorial validity of an existing eating attitude inventory for use with exercisers. The Eating Attitude Test (EAT is a 26-item measure that yields a single index of disordered eating attitudes. The original factor analysis showed three interrelated factors: Dieting behavior (13-items, oral control (7-items, and bulimia nervosa-food preoccupation (6-items. The primary purpose of the study was to examine the factorial validity of the EAT among a sample of exercisers. The second purpose was to investigate relationships between eating attitudes scores and selected psychological constructs. In stage one, 598 regular exercisers completed the EAT. Confirmatory factor analysis (CFA was used to test the single-factor, a three-factor model, and a four-factor model, which distinguished bulimia from food pre-occupation. CFA of the single-factor model (RCFI = 0.66, RMSEA = 0.10, the three-factor-model (RCFI = 0.74; RMSEA = 0.09 showed poor model fit. There was marginal fit for the 4-factor model (RCFI = 0.91, RMSEA = 0.06. Results indicated five-items showed poor factor loadings. After these 5-items were discarded, the three models were re-analyzed. CFA results indicated that the single-factor model (RCFI = 0.76, RMSEA = 0.10 and three-factor model (RCFI = 0.82, RMSEA = 0.08 showed poor fit. CFA results for the four-factor model showed acceptable fit indices (RCFI = 0.98, RMSEA = 0.06. Stage two explored relationships between EAT scores, mood, self-esteem, and motivational indices toward exercise in terms of self-determination, enjoyment and competence. Correlation results indicated that depressed mood scores positively correlated with bulimia and dieting scores. Further, dieting was inversely related with self-determination toward exercising. Collectively, findings suggest that a 21-item four-factor model shows promising validity coefficients

Exercise electrocardiogram testing in two brothers with different outcome – a case study exercise testing in master cyclists

Directory of Open Access Journals (Sweden)

Rüst CA

2013-06-01

Full Text Available Christoph Alexander Rüst,1 Beat Knechtle,1,2 Thomas Rosemann11Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland; 2Gesundheitszentrum St Gallen, St Gallen, SwitzerlandAbstract: The cases of two brothers training and competing as master cyclists and both preparing for a cycling tour are presented. The older brother aged 66 years went first to the primary care physician and presented with an asymptomatic depression in the exercise stress test of the ST segment in V5 and V6 during recovery after complete exhaustion. Coronary angiography revealed a multi vessel coronary artery disease and he underwent bypass surgery. One year later, he successfully completed his planned cycling tour of ~600 km in seven stages and covering ~12,000 m of total ascent. The younger brother aged 59 years went a few months later to the primary care physician and also performed asymptomatic exercise stress testing without changes in the ST segments. Unfortunately, 2 months later he suffered a cardiac arrest during his cycling tour and survived following immediate successful cardiopulmonary resuscitation on the road by his cycling colleagues. Immediate invasive coronary arteriography showed a complete stenosis of the trunk of arteria coronaria sinistra (left coronary artery, a 40%–50% stenosis of ramus circumflexus, and a 20% stenosis of arteria coronaria dextra (right coronary artery. The left coronary artery was dilated and he continued cycling 2 months later. In both brothers, familial hypercholesterolemia was the main cardiovascular risk factor for the multi vessel coronary artery disease. A negative exercise electrocardiogram in siblings with an increased risk for coronary artery disease seemed not to exclude an advanced multi vessel coronary artery disease. In master athletes with asymptomatic exercise electrocardiogram but a positive family history, further examinations should be performed in order to detect

Biomechanical Evaluation of an Electric Power-Assisted Bicycle by a Musculoskeletal Model

Science.gov (United States)

Takehara, Shoichiro; Murakami, Musashi; Hase, Kazunori

In this study, we construct an evaluation system for the muscular activity of the lower limbs when a human pedals an electric power-assisted bicycle. The evaluation system is composed of an electric power-assisted bicycle, a numerical simulator and a motion capture system. The electric power-assisted bicycle in this study has a pedal with an attached force sensor. The numerical simulator for pedaling motion is a musculoskeletal model of a human. The motion capture system measures the joint angles of the lower limb. We examine the influence of the electric power-assisted force on each muscle of the human trunk and legs. First, an experiment of pedaling motion is performed. Then, the musculoskeletal model is calculated by using the experimental data. We discuss the influence on each muscle by electric power-assist. It is found that the muscular activity is decreased by the electric power-assist bicycle, and the reduction of the muscular force required for pedaling motion was quantitatively shown for every muscle.

A Remote Power Management Strategy for the Solar Energy Powered Bicycle

Directory of Open Access Journals (Sweden)

Chung-Hsing Chao

2011-12-01

Full Text Available In this paper, a solar energy powered bicycle by a wireless sensor network (WSN far-end network monitoring solar energy to transfer the electrical energy storage and the effectiveness analysis is proposed. In order to achieve this goal, an embarked ZigBee by a solar-powered bicycle the far-end wireless network supervisory system is setup. Experimental results prove that our prototype, the solar energy powered bicycle, can manage the solar energy for charging two Lead-Acid batteries pack. As a result, the user by the wireless network in parking period knows the data on the amount of immediate solar radiation, the degree of illumination, the ambient temperature, and electrical energy storage capacity information by the internet interface.

Incremental exercise test performance with and without a respiratory ...

African Journals Online (AJOL)

Incremental exercise test performance with and without a respiratory gas collection system. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... Industrial- type mask wear is thought to impair exercise performance through increased respiratory dead space, flow ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Decreases in left atrial compliance during early-stage exercise are related to exercise intolerance in asymptomatic significant mitral stenosis.

Science.gov (United States)

Jung, Mi-Hyang; Jung, Hae Ok; Lee, Jung-Won; Youn, Ho-Joong

2017-11-01

Doppler-driven net atrioventricular compliance (C n ), which represents left atrial (LA) compliance, is an important determinant of pulmonary hypertension in mitral stenosis (MS). We hypothesized that decreases in C n during early-stage exercise underlie exercise intolerance in patients with MS. Thirty-three asymptomatic patients with significant MS (valve area 1.24 ± 0.16 cm 2 ) underwent resting and bicycle exercise echocardiography. LA compliance and conventional parameters were assessed at each workload. The patients were classified into two groups based on whether they developed dyspnea during exercise: an exercise-intolerance group (n = 22) and an exercise-tolerance group (n = 11). Moreover, "50 W" was defined as an early exercise stage. Although the groups had similar resting characteristics, there were striking differences in their echocardiographic parameters from the early stages of exercise. The relative C n decrease at 50 W (expressed as a percentage of the resting C n ) was significantly greater in the exercise-intolerance group (70.3 ± 15.4% vs 49.7 ± 9.7%, P intolerance group (P = .0005). Furthermore, differences in the trends in this parameter were observed between the two groups (P intolerance (adjusted OR 1.105, 95% CI 1.030-1.184) after adjustment for other conventional parameters. Decreases in C n during early-stage exercise are an important mechanism underlying exercise intolerance in MS. © 2017, Wiley Periodicals, Inc.

A multi-modal network approach to model public transport accessibility impacts of bicycle-train integration policies

NARCIS (Netherlands)

Geurs, Karst Teunis; La Paix Puello, Lissy Cesarina; van Weperen, Sander

2016-01-01

In the Netherlands, the bicycle plays an important in station access and, to a lesser extent, in station egress. There is however fairly little knowledge in the potential effects of bicycle-train integration policies. The aim of this paper is to examine the impacts of bicycle-train integration

Unilateral Arm Crank Exercise Test for Assessing Cardiorespiratory Fitness in Individuals with Hemiparetic Stroke

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Kazuaki Oyake

2017-01-01

Full Text Available Cardiorespiratory fitness assessment with leg cycle exercise testing may be influenced by motor impairments in the paretic lower extremity. Hence, this study examined the usefulness of a unilateral arm crank exercise test to assess cardiorespiratory fitness in individuals with stroke, including sixteen individuals with hemiparetic stroke (mean ± SD age, 56.4±7.5 years and 12 age- and sex-matched healthy controls. Participants performed the unilateral arm crank and leg cycle exercise tests to measure oxygen consumption (V˙O2 and heart rate at peak exercise. The V˙O2 at peak exercise during the unilateral arm crank exercise test was significantly lower in the stroke group than in the control group (p<0.001. In the stroke group, the heart rate at peak exercise during the unilateral arm crank exercise test did not significantly correlate with the Brunnstrom recovery stages of the lower extremity (p=0.137, whereas there was a significant correlation during the leg cycle exercise test (rho = 0.775, p<0.001. The unilateral arm crank exercise test can detect the deterioration of cardiorespiratory fitness independently of lower extremity motor impairment severity in individuals with hemiparetic stroke. This study is registered with UMIN000014733.

Wolff-Parkinson-White syndrome: a single exercise stress test might be misleading.

Science.gov (United States)

Salavitabar, Arash; Silver, Eric S; Liberman, Leonardo

2017-05-01

Risk stratification of patients with Wolff-Parkinson-White syndrome for sudden death is a complex process, particularly in understanding the utility of the repeat exercise stress test. We report a case of an 18-year-old patient who was found to have a high-risk pathway by both invasive and exercise stress testing after an initial exercise stress test showing beat-to-beat loss of pre-excitation.

An Association Rule Based Method to Integrate Metro-Public Bicycle Smart Card Data for Trip Chain Analysis

Directory of Open Access Journals (Sweden)

De Zhao

2018-01-01

Full Text Available Smart card data provide valuable insights and massive samples for enhancing the understanding of transfer behavior between metro and public bicycle. However, smart cards for metro and public bicycle are often issued and managed by independent companies and this results in the same commuter having different identity tags in the metro and public bicycle smart card systems. The primary objective of this study is to develop a data fusion methodology for matching metro and public bicycle smart cards for the same commuter using historical smart card data. A novel method with association rules to match the data derived from the two systems is proposed and validation was performed. The results showed that our proposed method successfully matched 573 pairs of smart cards with an accuracy of 100%. We also validated the association rules method through visualization of individual metro and public bicycle trips. Based on the matched cards, interesting findings of metro-bicycle transfer have been derived, including the spatial pattern of the public bicycle as first/last mile solution as well as the duration of a metro trip chain.

A summary of design, policies and operational characteristics for shared bicycle/bus lanes.

Science.gov (United States)

2012-07-01

This report contains the results of an investigation of the design and operation of shared bicycle/bus lanes in municipalities in the United States and other countries. These lanes are designated for use by public transit buses, bicycles, and usually...

Effects of exercise on insulin binding to human muscle

International Nuclear Information System (INIS)

Bonen, A.; Tan, M.H.; Clune, P.; Kirby, R.L.

1985-01-01

A procedure was developed to measure insulin binding to human skeletal muscle obtained via the percutaneous muscle biopsy technique. With this method the effects of exercise on insulin binding were investigated. Subjects (n = 9) exercised for 60 min on a bicycle ergometer at intensities ranging from 20-86% maximum O 2 consumption (VO 2 max). Blood samples were obtained before, during, and after exercise and analyzed for glucose and insulin. Muscle samples (250 mg) for the vastus lateralis were obtained 30 min before exercise, at the end of exercise, and 60 min after exercise. Two subjects rested during the experimental period. There was no linear relationship between exercise intensities and the changes in insulin binding to human muscle. At rest (n = 2) and at exercise intensities below 60% VO 2 max (n = 5) no change in insulin binding occurred (P greater than 0.05). However, when exercise occurred at greater than or equal to 69% VO 2 max (n = 4), a pronounced decrement in insulin binding (30-50%) was observed (P less than 0.05). This persisted for 60 min after exercise. These results indicate that insulin binding in human muscle is not altered by 60 min of exercise at less than or equal to 60% VO 2 max but that a marked decrement occurs when exercise is greater than or equal to 69% VO 2 max

MIT-Skywalker: Evaluating comfort of bicycle/saddle seat.

Science.gov (United States)

Goncalves, Rogerio S; Hamilton, Taya; Daher, Ali R; Hirai, Hiroaki; Krebs, Hermano I

2017-07-01

The MIT-Skywalker is a robotic device developed for the rehabilitation of gait and balance after a neurological injury. This device has been designed based on the concept of a passive walker and provides three distinct training modes: discrete movement, rhythmic movement, and balance training. In this paper, we present our efforts to evaluate the comfort of a bicycle/saddle seat design for the system's novel actuated body weight support device. We employed different bicycle and saddle seats and evaluated comfort using objective and subjective measures. Here we will summarize the results obtained from a study of fifteen healthy subjects and one stroke patient that led to the selection of a saddle seat design for the MIT-Skywalker.

Effects of aerobic exercise training on maternal and neonatal outcome: a randomized controlled trial on pregnant women in Iran

International Nuclear Information System (INIS)

Ghodsi, Z.; Asltoghiri, M.

2014-01-01

Objective: To assess the effect of aerobic exercise training on maternal and neonatal outcome. Methods: The case-control study was conducted between January and July, 2011. It was approved by the Research Ethics Committee of Toyserkan Azad University, and data was collected at prenatal clinics and delivery centres located in Hamedan, Iran. It comprised 80 pregnant women between 20-26 weeks of gestation randomly assigned to two equal and matching groups of cases and controls. The intervention group did exercise continuously on a bicycle ergometre for 15 minutes, three times a week; the intensity being 50-60% of maximal heart rate. The control group did not do any exercise training. All information was obtained from the clinics, delivery centres, and from the reports of delivery room midwives. Results: No statistically significant difference was found between the two groups in gestational weight gain, pregnancy length, mode of delivery, first and second stage of labour, perineal tear, and 1st and 5th min Apgar score. Mean neonatal weight was significantly less in the intervention group than the control group (p<0.001). Conclusion: Exercising on a bicycle ergometer during pregnancy seems to be safe for the mother and the neonate. (author)

New Exercise-Dipyridamole Combined Test for Nuclear Cardiology in Insufficient Effort: Appropriate Diagnostic Sensitivity Keeping Exercise Prognosis

Energy Technology Data Exchange (ETDEWEB)

Cortinas, Inés Vidal, E-mail: invi@montevideo.com.uy; Beretta, Mario; Alonso, Omar; Mut, Fernando [Departamento de Medicina Nuclear do Hospital ‘Asociación Española’, Br. Artigas 1515, Montevideo (Uruguay)

2015-08-15

Myocardial perfusion scintigraphy (MPS) in patients not reaching 85% of the maximum predicted heart rate (MPHR) has reduced sensitivity. In an attempt to maintain diagnostic sensitivity without losing functional exercise data, a new exercise and dipyridamole combined protocol (EDCP) was developed. Our aim was to evaluate the feasibility and safety of this protocol and to compare its diagnostic sensitivity against standard exercise and dipyridamole protocols. In patients not reaching a sufficient exercise (SE) test and with no contraindications, 0.56 mg/kg of dipyridamole were IV administered over 1 minute simultaneously with exercise, followed by 99mTc-MIBI injection. Of 155 patients, 41 had MPS with EDCP, 47 had a SE test (≥ 85% MPHR) and 67 underwent the dipyridamole alone test (DIP). They all underwent coronary angiography within 3 months. The three stress methods for diagnosis of coronary lesions had their sensitivity compared. For stenosis ≥ 70%, EDCP yielded 97% sensitivity, SE 90% and DIP 95% (p = 0.43). For lesions ≥ 50%, the sensitivities were 94%, 88% and 95%, respectively (p = 0.35). Side effects of EDCP were present in only 12% of the patients, significantly less than with DIP (p < 0.001). The proposed combined protocol is a valid and safe method that yields adequate diagnostic sensitivity, keeping exercise prognostic information in patients unable to reach target heart rate, with fewer side effects than the DIP.

Bicycling to Work and Primordial Prevention of Cardiovascular Risk

DEFF Research Database (Denmark)

Grøntved, Anders; Koivula, Robert W; Johansson, Ingegerd

2016-01-01

of incident obesity, hypertension, hypertriglyceridemia, and impaired glucose tolerance, comparing individuals who commuted to work by bicycle with those who used passive modes of transportation. We also examined the relationship of change in commuting mode with incidence of these clinical risk factors......% CI 0.74-0.91) compared with participants not cycling to work at both times points or who switched from cycling to other modes of transport during follow-up. CONCLUSIONS: These data suggest that commuting by bicycle to work is an important strategy for primordial prevention of clinical cardiovascular...... risk factors among middle-aged men and women....

Evaluation of the dispersion effect in through movement bicycles at signalized intersection via cellular automata simulation

Science.gov (United States)

Jiang, Hang; Ma, Yongjian; Jiang, Lin; Chen, Guozhou; Wang, Dongwei

2018-05-01

At signalized intersection areas, bicycle traffic presents a dispersion feature which may influence the movements of vehicles during peak period. The primary objective of this study is to simulate the dispersion effect in through-movement bicycle traffic at intersection areas and evaluate its influence on through-movement traffic. A cellular automata (CA) model is developed and validated to simulate the operations of through-movement bicycle traffic departing from two types of intersection approaches. Simulation results show that bicycles benefit from the dispersion effect when they depart from the approach with an exclusive right-turn vehicle lane. But when bicycles travel from the approach with a shared right-turn and through vehicle lane, the dispersion effect will result in friction interference and block interference on through-movement vehicles. Bicycle interferences reduce the vehicle speed and increase the delay of through-movement vehicles. The policy implications in regard to the dispersion effect from two types of approaches are discussed to improve the performance of through-movement traffic operations at signalized intersections.

Comparison of five bicycle facility designs in signalized intersections using traffic conflict studies

DEFF Research Database (Denmark)

Madsen, Tanja Kidholm Osmann; Lahrmann, Harry Spaabæk

2017-01-01

Highlights •Traffic conflict study comparing cyclists’ relative risk for five bicycle layouts. •Watchdog video analysis software applied to reduce video data. •Video analysis software necessary to conduct larger conflict studies. •Recessed bicycle track seems to provide the highest safety level...

Six-minute stepper test: a valid clinical exercise tolerance test for COPD patients

Directory of Open Access Journals (Sweden)

Grosbois JM

2016-03-01

Full Text Available JM Grosbois,1,2 C Riquier,3 B Chehere,4 J Coquart,5 H Béhal,6 F Bart,2 B Wallaert,2,3 C Chenivesse3 1FormAction Santé, Pérenchies, France; 2Department of Respiratory Medicine, Centre Hospitalier Germon et Gauthier, Béthune, France; 3Department of Respiratory Medicine Immunology and Allergy, Centre Hospitalier Universitaire de Lille, Competence Center for rare lung diseases, University Lille 2, Lille, France; 4EA 7369, URePSSS, Multidisciplinary Research Unit in Sport Health Society, University Lille 2, Lille, France; 5Faculty of Sport Sciences, Sports and Physical Activity, Center for Ecology and Transformation, University of Rouen, Mont Saint Aignan, France; 6Department of Statistical Methods and Biostatistics, Centre Hospitalier Universitaire de Lille, University of Lille Nord, Lille, France Introduction: Exercise tolerance testing is an integral part of the pulmonary rehabilitation (PR management of patients with chronic obstructive pulmonary disease (COPD. The 6-minute stepper test (6MST is a new, well-tolerated, reproducible exercise test, which can be performed without any spatial constraints.Objective: The aim of this study was to compare the results of the 6MST to those obtained during a 6-minute walk test (6MWT and cardiopulmonary exercise testing (CPET in a cohort of COPD patients.Methods: Ninety-one COPD patients managed by outpatient PR and assessed by 6MST, 6MWT, and CPET were retrospectively included in this study. Correlations between the number of steps on the 6MST, the distance covered on the 6MWT, oxygen consumption, and power at the ventilatory threshold and at maximum effort during CPET were analyzed before starting PR, and the improvement on the 6MST and 6MWT was compared after PR.Results: The number of steps on the 6MST was significantly correlated with the distance covered on the 6MWT (r=0.56; P<0.0001, the power at maximum effort (r=0.46; P<0.0001, and oxygen consumption at maximum effort (r=0.39; P<0

Assessing the Bicycle Network in St. Louis: A PlaceBased User-Centered Approach

Directory of Open Access Journals (Sweden)

Bram Boettge

2017-02-01

Full Text Available To transition towards sustainability and increase low-impact transportation, city planners are integrating bicycle infrastructure in urban landscapes. Yet, this infrastructure only promotes cycling according to how well it is sited within a specific city. How to best site bicycle facilities is essential for sustainability planning. We review approaches to assessing and siting new bicycle facilities. Following sustainability science, we argue that active cyclists should be consulted to incorporate users’ site-specific knowledge into bicycle infrastructure assessments. We then pilot an approach that surveys cyclists concerning level of stress along routes ridden in St. Louis, MO, USA. Among the active cyclists surveyed (n = 89, we found stress correlates with speed limit, roadway classification, and number of lanes. Although cyclists surveyed in St. Louis prefer roads with bike lanes over roads with sharrows or no infrastructure, the presence of bicycle infrastructure had no correlation with reported levels of stress. The piloted survey and spatial analytic tool are transferable to other localities. For planners, the maps generated by this participant data approach identify high-stress routes as targets of new infrastructure or information to direct cyclists to safer routes. For bicyclists, the maps generated identify low-stress routes for recreation and commuting.

Traumatic Globe Subluxation and Intracranial Injury Caused by Bicycle Brake Handle

OpenAIRE

Poroy; Cibik; Yazici

2016-01-01

Introduction Penetration of a bicycle brake handle into the orbit is a rare and serious type of trauma. Globe subluxation due to such trauma has not been previously reported. Case Presentation A 10-year-old girl presented after falling from a bicycle, which resulted in the handbrake penetrating her right upper eyelid. On examination, the globe was subluxated anteriorly, there was no light perception, and the pupilla was fixed and ...

Bicycles, transportation sustainability, and quality of life.

Science.gov (United States)

2014-01-01

The research presented in this report focuses on the exploration of a variety of objective and subjective quality of life indicators and approaches for bicycle transportation using a mixed methods approach. The authors have created a conceptual frame...

How bicycle level of traffic stress correlate with reported cyclist accidents injury severities: A geospatial and mixed logit analysis.

Science.gov (United States)

Chen, Chen; Anderson, Jason C; Wang, Haizhong; Wang, Yinhai; Vogt, Rachel; Hernandez, Salvador

2017-11-01

Transportation agencies need efficient methods to determine how to reduce bicycle accidents while promoting cycling activities and prioritizing safety improvement investments. Many studies have used standalone methods, such as level of traffic stress (LTS) and bicycle level of service (BLOS), to better understand bicycle mode share and network connectivity for a region. However, in most cases, other studies rely on crash severity models to explain what variables contribute to the severity of bicycle related crashes. This research uniquely correlates bicycle LTS with reported bicycle crash locations for four cities in New Hampshire through geospatial mapping. LTS measurements and crash locations are compared visually using a GIS framework. Next, a bicycle injury severity model, that incorporates LTS measurements, is created through a mixed logit modeling framework. Results of the visual analysis show some geospatial correlation between higher LTS roads and "Injury" type bicycle crashes. It was determined, statistically, that LTS has an effect on the severity level of bicycle crashes and high LTS can have varying effects on severity outcome. However, it is recommended that further analyses be conducted to better understand the statistical significance and effect of LTS on injury severity. As such, this research will validate the use of LTS as a proxy for safety risk regardless of the recorded bicycle crash history. This research will help identify the clustering patterns of bicycle crashes on high-risk corridors and, therefore, assist with bicycle route planning and policy making. This paper also suggests low-cost countermeasures or treatments that can be implemented to address high-risk areas. Specifically, with the goal of providing safer routes for cyclists, such countermeasures or treatments have the potential to substantially reduce the number of fatalities and severe injuries. Published by Elsevier Ltd.

Exercise testing, limitation and training in patients with cystic fibrosis. A personalized approach

NARCIS (Netherlands)

Werkman, M.S.

2014-01-01

Exercise testing and training are cornerstones in regular CF care. However, no consensus exists in literature about which exercise test protocol should be used for individual patients. Furthermore, divergence exists in insights about both the dominant exercise limiting mechanisms and the

Association of Sociodemographic and Perceived Environmental Factors with Public Bicycle Use among Taiwanese Urban Adults

Directory of Open Access Journals (Sweden)

Yung Liao

2016-03-01

Full Text Available Background: This study examined the sociodemographic and perceived environmental factors associated with public bicycle use among Taiwanese urban adults. Methods: A random-digit-dialing telephone-based cross-sectional survey was administered to Taiwanese urban adults aged 20–64 years in 2015. Data on sociodemographic variables, perceived environmental factors (for attributes identified in the International Physical Activity Questionnaire-Environmental Module, and public bicycle use were obtained from 1002 adults in three cities. Adjusted logistic regression was used. Results: After adjustment for potential confounders, the results showed that adults aged 20–29 years (odds ratio (OR = 4.42 with a university degree or higher (OR = 2.03 were more likely to use public bicycles. In addition, adults living in Kaohsiung City were less likely to use public bicycles (OR = 0.24. Adults who saw people being active (OR = 1.76; 95% CI: 1.05–2.86 and had positive aesthetic experiences of their environment (OR = 1.69 were more likely to use public bicycles. Conclusions: Our findings suggest that seeing physically active people and positive aesthetic perceptions of the environment are key factors for developing transportation policies and intervention strategies for promoting public bicycle use among Taiwanese urban adults.

Noninvasive assessment of changes in myocardial perfusion and ventricular performance following exercise training

International Nuclear Information System (INIS)

Tubau, J.; Witztum, K.; Froelicher, V.; Jensen, D.; Atwood, E.; McKirnan, M.D.; Reynolds, J.; Ashburn, W.

1982-01-01

Seventeen coronary patients (CAD) underwent 201 Tl treadmill and radionuclide (RNV) ejection fraction supine bicycle testing before and after 5.6 +/- 1.6 (mean +/- SD) months of an exercise program. Thallium data were assessed both using analog images and a computerized circumferential profile technique. Patients exercised on the treadmill to a higher workload after the exercise program, but achieved a similar pressure-rate product. When interpreting the analog thallium images, only 50% agreement was obtained for the assessment of changes in myocardial perfusion (pre/post-training). The computer technique, however, had low inter-intraobserver variability (6%) and better agreement (90.5%). Using the circumferential profile method, five patients improved (a total of 11 regions) and one patient worsened (with two regions). Before the exercise program, the ejection fraction (EF) response to supine bike exercise was normal (an increase greater than 11%) in four, flat in seven, and severely abnormal (a decrease of more than 4%) in six patients. After the exercise program, even though achieving similar or higher pressure-rate products, six patients improved their EF response, nine did not change, and two worsened. Of the five patients who improved their thallium images, one improved his EF response, two remained normal, and two did not change. One patient worsened both his thallium study and the EF response after the exercise program. Changes in thallium exercise images and the EF response to supine exercise occurred in our patients after an exercise program, but were not always concordant. Indeed, of five patients with exercise-induced ischemic ST changes before and after training, the EF response improved in three whereas myocardial perfusion was unchanged. Reasons for this lack of agreement are discussed, and have been considered in the planning of a randomized trial of the effects of an exercise program on myocardial perfusion and function

Bicycle-friendly infrastructure planning in Beijing and Copenhagen - between adapting design solutions and learning local planning cultures

DEFF Research Database (Denmark)

Zhao, Chunli; Carstensen, Trine Agervig; Nielsen, Thomas Alexander Sick

2018-01-01

Abstract Cities around the world are constructing bicycle infrastructure to increase cycling. However, identifying efficient design solutions and determining how bicycle infrastructure planning knowledge can be integrated into comprehensive policy remains a challenge. The objective of this paper...... is to shed light on the strengths and weaknesses of current bicycle infrastructure planning in both an experienced city, Copenhagen, and in a less experienced city, Beijing. The paper examines how local design solutions are identified, how efficient they are and to what extent bicycle infrastructure planning...

Hydraulic brake-system for a bicycle

NARCIS (Netherlands)

Van Frankenhuyzen, J.

2007-01-01

The invention relates to a hydraulic brake system for a bicycle which may or may not be provided with an auxiliary motor, comprising a brake disc and brake claws cooperating with the brake disc, as well as fluid-containing channels (4,6) that extend between an operating organ (1) and the brake

New Exercise-Dipyridamole Combined Test for Nuclear Cardiology in Insufficient Effort: Appropriate Diagnostic Sensitivity Keeping Exercise Prognosis

Directory of Open Access Journals (Sweden)

Inés Vidal Cortinas

2015-08-01

Full Text Available AbstractBackground:Myocardial perfusion scintigraphy (MPS in patients not reaching 85% of the maximum predicted heart rate (MPHR has reduced sensitivity.Objectives:In an attempt to maintain diagnostic sensitivity without losing functional exercise data, a new exercise and dipyridamole combined protocol (EDCP was developed. Our aim was to evaluate the feasibility and safety of this protocol and to compare its diagnostic sensitivity against standard exercise and dipyridamole protocols.Methods:In patients not reaching a sufficient exercise (SE test and with no contraindications, 0.56 mg/kg of dipyridamole were IV administered over 1 minute simultaneously with exercise, followed by 99mTc-MIBI injection.Results:Of 155 patients, 41 had MPS with EDCP, 47 had a SE test (≥ 85% MPHR and 67 underwent the dipyridamole alone test (DIP. They all underwent coronary angiography within 3 months. The three stress methods for diagnosis of coronary lesions had their sensitivity compared. For stenosis ≥ 70%, EDCP yielded 97% sensitivity, SE 90% and DIP 95% (p = 0.43. For lesions ≥ 50%, the sensitivities were 94%, 88% and 95%, respectively (p = 0.35. Side effects of EDCP were present in only 12% of the patients, significantly less than with DIP (p < 0.001.Conclusions:The proposed combined protocol is a valid and safe method that yields adequate diagnostic sensitivity, keeping exercise prognostic information in patients unable to reach target heart rate, with fewer side effects than the DIP.

Incidence of Pneumothorax in Patients With Lymphangioleiomyomatosis Undergoing Pulmonary Function and Exercise Testing.

Science.gov (United States)

Taveira-DaSilva, Angelo M; Julien-Williams, Patricia; Jones, Amanda M; Moss, Joel

2016-07-01

Because pneumothorax is frequent in lymphangioleiomyomatosis, patients have expressed concerns regarding the risk of pneumothorax associated with pulmonary function or exercise testing. Indeed, pneumothorax has been reported in patients with lung disease after both of these tests. The aim of this study was to determine the incidence of pneumothorax in patients with lymphangioleiomyomatosis during admissions to the National Institutes of Health Clinical Research Center between 1995 and 2015. Medical records were reviewed to identify patients who had a pneumothorax during their stay at the National Institutes of Health. A total of 691 patients underwent 4,523 pulmonary function tests and 1,900 exercise tests. Three patients developed pneumothorax after pulmonary function tests and/or exercise tests. The incidence of pneumothorax associated with lung function testing was 0.14 to 0.29 of 100 patients or 0.02 to 0.04 of 100 tests. The incidence of pneumothorax in patients undergoing exercise testing was 0.14 to 0.28 of 100 patients or 0.05 to 0.10 of 100 tests. The risk of pneumothorax associated with pulmonary function or exercise testing in patients with lymphangioleiomyomatosis is low. Published by Elsevier Inc.

Bronchial provocation testing does not detect exercise-induced laryngeal obstruction

DEFF Research Database (Denmark)

Walsted, Emil Schwarz; Hull, James H; Sverrild, Asger

2017-01-01

INTRODUCTION: Exercise-induced laryngeal obstruction (EILO) is a key differential diagnosis for asthma in the presence of exertional respiratory symptoms. Continuous laryngoscopy during exercise (CLE), the current gold standard diagnostic test for EILO, has practical limitations. We aimed...... to establish if inspiratory flow data obtained during standard bronchoprovocation testing, to establish the presence of extra-thoracic hyper-responsiveness, may prove diagnostic for EILO and thus preclude requirement for CLE testing. METHODS: We consecutively evaluated 37 adult subjects with exertional dyspnea...

Plasma concentration of high-mobility group box 1 (HMGB1) after 100 drop to vertical jumps and after a 1200-km bicycle race.

Science.gov (United States)

Behringer, M; Kilian, Y; Montag, J; Geesmann, B; Mester, J

2016-01-01

High-mobility group box 1 (HMGB1) has recently been reported to be involved in proinflammation and tissue repair. Therefore, we hypothesized that HMGB1 is released into the bloodstream after eccentric exercises or prolonged endurance activities. Blood samples from 11 participants that performed 100 drop to vertical jumps (DVJ) and from 10 participants that took part in the 1200-km 'Paris-Brest-Paris' bicycle race (PBP) were tested for HMGB1 and creatine kinase (CK) levels. CK increased after both DVJ (pre: 150.6 ± 81.5 U/L; post: 188.8 ± 95.5 U/L 8 h: 790.5 ± 346.4 U/L) and PBP (pre: 81.3 ± 36.4 U/L; post: 725.2 ± 229.5 U/L; 12 h: 535.8 ± 188.6 U/L), indicating membrane damage. However, HMGB1 plasma levels remained below the detection limit (78 pg/mL) of the applied enzyme-linked immunosorbent assay kit for all blood samples analysed. That is, neither high intensity eccentric exercises (DVJ) nor prolonged endurance events (PBP) seemed to affect HMGB1 levels in blood at selected time points.

What do we know about bicycle helmets?

NARCIS (Netherlands)

Bogerd, C.P. Halldin, P. Houtenbos, M. Otte, D. Rossi, R.M. Walker, L. Willinger, R. & Shinar, D.

2012-01-01

Cycling is an excellent sustainable alternative to driving for many journeys. But cyclists have fewer safety options than car-users, with a helmet being the main safety device that is available. However, there are indications that increasing bicycle helmet usage through legislation causes

What Factors Explain Bicycling and Walking for Commuting by ELSA-Brasil Participants?

Science.gov (United States)

de Matos, Sheila Maria Alvim; Pitanga, Francisco José Gondim; Almeida, Maria da Conceição C; Queiroz, Ciro Oliveira; Dos Santos, Clarice Alves; de Almeida, Rogerio Tosta; da Silva, Ianne Tayrine Martins; Griep, Rosane Harter; Amorim, Leila Denise Alves Ferreira; Patrão, Ana Luísa; Aquino, Estela M L

2018-03-01

To analyze the factors associated with commuting by bicycling and walking in adult participants from ELSA-Brasil (Longitudinal Study of Adult Health). Cross-sectional. Six teaching/research institutions throughout Brazil. A total of 15 105 civil servants. Commuting by bicycling and walking was analyzed using the long-form International Physical Activity Questionnaire. A hierarchical model containing possible factors associated with commuting by bicycling and walking was constructed. Crude and adjusted odds ratios were calculated using multinomial logistic regression. Considering the 2 forms of commuting, 66% of the participants were being considered inactive or insufficiently active. In women, being "heavier," feeling unsafe practicing physical activity, and being a former smoker were factors negatively associated with commuting by bicycling and walking. In men, active commuting was less common among those who were overweight or had abdominal obesity, those with a negative perception of safety, and those reporting that there was nowhere suitable in the neighborhood to practice physical activity. Obesity and negative perceptions in the neighborhood are associated with inactive or insufficiently active commuting. The relevance of this finding for public health is reinforce developing policies aimed at promoting health in Brazil and in other countries with similar characteristics.

Omega-3 fatty acid supplementation enhances stroke volume and cardiac output during dynamic exercise.

Science.gov (United States)

Walser, Buddy; Stebbins, Charles L

2008-10-01

Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have beneficial effects on cardiovascular function. We tested the hypotheses that dietary supplementation with DHA (2 g/day) + EPA (3 g/day) enhances increases in stroke volume (SV) and cardiac output (CO) and decreases in systemic vascular resistance (SVR) during dynamic exercise. Healthy subjects received DHA + EPA (eight men, four women) or safflower oil (six men, three women) for 6 weeks. Both groups performed 20 min of bicycle exercise (10 min each at a low and moderate work intensity) before and after DHA + EPA or safflower oil treatment. Mean arterial pressure (MAP), heart rate (HR), SV, CO, and SVR were assessed before exercise and during both workloads. HR was unaffected by DHA + EPA and MAP was reduced, but only at rest (88 +/- 5 vs. 83 +/- 4 mm Hg). DHA + EPA augmented increases in SV (14.1 +/- 6.3 vs. 32.3 +/- 8.7 ml) and CO (8.5 +/- 1.0 vs. 10.3 +/- 1.2 L/min) and tended to attenuate decreases in SVR (-7.0 +/- 0.6 vs. -10.1 +/- 1.6 mm Hg L(-1) min(-1)) during the moderate workload. Safflower oil treatment had no effects on MAP, HR, SV, CO or SVR at rest or during exercise. DHA + EPA-induced increases in SV and CO imply that dietary supplementation with these fatty acids can increase oxygen delivery during exercise, which may have beneficial clinical implications for individuals with cardiovascular disease and reduced exercise tolerance.

How the Netherlands became a bicycle nation : users, firms and intermediaries, 1860-1940

NARCIS (Netherlands)

Tjong Tjin Tai, S.E.; Veraart, F.C.A.; Davids, M.

2015-01-01

In 1925, the Netherlands was a country of cyclists and cycle producers, as all classes cycled and almost all cycles were produced domestically. The bicycle was not a Dutch invention and the country had an open economy, and this raises the question ‘how did the Netherlands become a bicycle nation?’

Cycle for Science: An informal outreach program connecting K-12 students with renewable energy and physics through miniature 3D-printed, solar-powered bicycles

Science.gov (United States)

Woods-Robinson, R.; Case, E.

2017-12-01

Engaging communities with renewable energy is key to fighting climate change. Cycle for Science, an innovative STEM outreach organization, has reached more than 3,000 K-12 students across the United States by bringing early-career female scientists into classrooms to teach basic physics and solar energy engineering through hands-on, DIY science activities. We designed a fleet of miniature, 3D-printed, solar-powered bicycles called "Sol Cycles" to use as teaching tools. Traveling by bicycle, Cycle for Science has brought them to rural and urban communities across the U.S. in two major efforts so far: one traversing the country (2015), and one through central California (2017). The program involves (1) introducing the scientists and why they value science, (2) running a skit to demonstrate how electrons and photons interact inside the solar panel, (3) assembling the Sol Cycles, (4) taking students outdoors to test the effects of variables (e.g. light intensity) on the Sol Cycles' movement, (5) and debriefing about the importance of renewable energy. In addition to physics and solar energy, the lessons teach the scientific process, provide tactile engagement with science, and introduce a platform to engage students with climate change impacts. By cycling to classrooms, we provide positive examples of low-impact transportation and a unique avenue for discussing climate action. It was important that this program extend beyond the trips, so the lesson and Sol Cycle design are open source to encourage teachers and students to play, change and improve the design, as well as incorporate new exercises (e.g. could you power the bicycle by wind?). Additionally, it has been permanently added to the XRaise Lending Library at Cornell University, so teachers across the world can implement the lesson. By sharing our project at AGU, we aim to connect with other scientists, educators, and concerned citizens about how to continue to bring renewable energy lessons into classrooms.

Stereocontrolled synthesis of polyhydroxylated bicyclic azetidines as a new class of iminosugars.

Science.gov (United States)

Malinowski, Maciej; Hensienne, Raphaël; Kern, Nicolas; Tardieu, Damien; Bodlenner, Anne; Hazelard, Damien; Compain, Philippe

2018-06-12

We report herein the development of a stereodivergent route towards polyhydroxylated bicyclic azetidine scaffolds, namely 6-azabicyclo[3.2.0]heptane derivatives. The strategy hinges on a common bicyclic β-lactam precursor, which is forged by way of a rare example of a cationic Dieckmann-type reaction, followed by IBX-mediated desaturation. Substrate-controlled diastereoselective oxidations then allow the divergent preparation of novel iminosugar mimics.

Translation of incremental talk test responses to steady-state exercise training intensity.

Science.gov (United States)

Lyon, Ellen; Menke, Miranda; Foster, Carl; Porcari, John P; Gibson, Mark; Bubbers, Terresa

2014-01-01

The Talk Test (TT) is a submaximal, incremental exercise test that has been shown to be useful in prescribing exercise training intensity. It is based on a subject's ability to speak comfortably during exercise. This study defined the amount of reduction in absolute workload intensity from an incremental exercise test using the TT to give appropriate absolute training intensity for cardiac rehabilitation patients. Patients in an outpatient rehabilitation program (N = 30) performed an incremental exercise test with the TT given every 2-minute stage. Patients rated their speech comfort after reciting a standardized paragraph. Anything other than a "yes" response was considered the "equivocal" stage, while all preceding stages were "positive" stages. The last stage with the unequivocally positive ability to speak was the Last Positive (LP), and the preceding stages were (LP-1 and LP-2). Subsequently, three 20-minute steady-state training bouts were performed in random order at the absolute workload at the LP, LP-1, and LP-2 stages of the incremental test. Speech comfort, heart rate (HR), and rating of perceived exertion (RPE) were recorded every 5 minutes. The 20-minute exercise training bout was completed fully by LP (n = 19), LP-1 (n = 28), and LP-2 (n = 30). Heart rate, RPE, and speech comfort were similar through the LP-1 and LP-2 tests, but the LP stage was markedly more difficult. Steady-state exercise training intensity was easily and appropriately prescribed at intensity associated with the LP-1 and LP-2 stages of the TT. The LP stage may be too difficult for patients in a cardiac rehabilitation program.

Effect of intermittent aerobic exercise on sleep quality and sleep disturbances in patients with rheumatoid arthritis

DEFF Research Database (Denmark)

Løppenthin, Katrine; Esbensen, Bente Appel; Jennum, Poul

2014-01-01

of an intermittent aerobic exercise intervention on sleep, assessed both objectively and subjectively in patients with rheumatoid arthritis. METHODS/DESIGN: A randomized controlled trial including 44 patients with rheumatoid arthritis randomly assigned to an exercise training intervention or to a control group....... The intervention consists of 18 session intermittent aerobic exercise training on a bicycle ergometer three times a week. Patients are evaluated according to objective changes in sleep as measured by polysomnography (primary outcome). Secondary outcomes include changes in subjective sleep quality and sleep...... disturbances, fatigue, pain, depressive symptoms, physical function, health-related quality of life and cardiorespiratory fitness. DISCUSSION: This trial will provide evidence of the effect of intermittent aerobic exercise on the improvement of sleep in patients with rheumatoid arthritis, which is considered...

On the Implications of Sense of Control over Bicycling : Design of a Physical Stamina-Aware Bike

OpenAIRE

Lee, Chao-Lung; Lee, Da; Cheng, Yun-Maw; Sandnes, Frode Eika; Chen, Li-Chieh; Chen, Wei-Chia

2010-01-01

Bicycling has become a mainstream activity among the environmental aware generation. Bicycling communities have gradually shown interests in quantitative data of the bicycling experiences such as road roughness, inclination, pollution, etc. Bikers utilize these data to infer the possible stamina cost and quality of surroundings. This supports them to make a better decision. This study assumes that fitness level indexed by stamina cost could enhance a biker's sense of c...

"Bicycles May Use Full Lane" Signage Communicates U.S. Roadway Rules and Increases Perception of Safety.

Science.gov (United States)

Hess, George; Peterson, M Nils

2015-01-01

Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to "get out of the way" to allow motorists to pass without changing lanes: "Bicycles May Use Full Lane" and "Share the Road" signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. "Bicycles May Use Full Lane" signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. "Share the Road" signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. "Bicycles May Use Full Lane" signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing "Share the Road" with "Bicycles May Use Full Lane" signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited.

"Bicycles May Use Full Lane" Signage Communicates U.S. Roadway Rules and Increases Perception of Safety.

Directory of Open Access Journals (Sweden)

George Hess

Full Text Available Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to "get out of the way" to allow motorists to pass without changing lanes: "Bicycles May Use Full Lane" and "Share the Road" signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. "Bicycles May Use Full Lane" signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. "Share the Road" signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. "Bicycles May Use Full Lane" signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing "Share the Road" with "Bicycles May Use Full Lane" signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited.

Distribution and predictors of exercise habits among pregnant women in the Danish National Birth Cohort

DEFF Research Database (Denmark)

Juhl, Mette; Madsen, Mia; Andersen, Anne-Marie Nybo

2012-01-01

alcohol consumption, and a healthy diet. Multiparity, a normal or less good self-rated health, smoking, and a less health conscious diet were the strongest predictors of not doing exercise. Women of 25 years or older, with metabolic or psychiatric disorders, or who had received subfecundity treatment were......Physical activity is recommended during pregnancy, although strong evidence on reproductive health is lacking. We present exercise habits and predictors of exercise during pregnancy. From the Danish National Birth Cohort (1996-2002), 88 200 singleton pregnancies were analyzed in logistic regression....... About one-third of the women exercised in early/mid pregnancy and slightly less in late pregnancy. Bicycling, swimming, and low-impact activities were most common. Exercising more than three times per week was strongly correlated with older age, being a student or out of work, eating disorders, moderate...

Safeguards system testing WSRC Insider Exercise Program (U)

International Nuclear Information System (INIS)

Robichaux, J.J.

1991-01-01

One of the major concerns related to the control and accountability of nuclear material located at DOE facilities is the theft or diversion of material by an insider. Many complex safeguards and security systems have been installed to provide timely detection and prevention of the removal of nuclear materials. The Westinghouse Savannah River Company's (WSRC) Material Control and Accountability (MC and A) section has implemented an insider exercise program designed to evaluate the effectiveness of these safeguards systems. Exercises consist of limited scope performance test. This paper describes the structure and controls for the insider exercise program at the Savannah River Site, the lessons learned over the past several years, and methods being utilized to improve the program

Diet and exercise changes following direct-to-consumer personal genomic testing.

Science.gov (United States)

Nielsen, Daiva Elena; Carere, Deanna Alexis; Wang, Catharine; Roberts, J Scott; Green, Robert C

2017-05-02

The impacts of direct-to-consumer personal genomic testing (PGT) on health behaviors such as diet and exercise are poorly understood. Our investigation aimed to evaluate diet and exercise changes following PGT and to determine if changes were associated with genetic test results obtained from PGT. Customers of 23andMe and Pathway Genomics completed a web-based survey prior to receiving PGT results (baseline) and 6 months post-results. Fruit and vegetable intake (servings/day), and light, vigorous and strength exercise frequency (days/week) were assessed. Changes in diet and exercise were examined using paired t-tests and linear regressions. Additional analyses examined whether outcomes differed by baseline self-reported health (SRH) or content of PGT results. Longitudinal data were available for 1,002 participants. Significant increases were observed for vegetable intake (mean Δ = 0.11 (95% CI = 0.05, 0.17), p = 0.0003) and strength exercise (Δ = 0.14 (0.03, 0.25), p = 0.0153). When stratified by SRH, significant increases were observed for all outcomes among lower SRH participants: fruit intake, Δ = 0.11 (0.02, 0.21), p = 0.0148; vegetable intake, Δ = 0.16 (0.07, 0.25), p = 0.0005; light exercise, Δ = 0.25 (0.03, 0.47), p = 0.0263; vigorous exercise, Δ = 0.23 (0.06, 0.41), p = 0.0097; strength exercise, Δ = 0.19 (0.01, 0.37), p = 0.0369. A significant change among higher SRH participants was only observed for light exercise, and in the opposite direction: Δ = -0.2468 (-0.06, -0.44), p = 0.0111. Genetic results were not consistently associated with any diet or exercise changes. The experience of PGT was associated with modest, mostly positive changes in diet and exercise. Associations were independent of genetic results from PGT.

Exercise Capacity and the Obesity Paradox in Heart Failure: The FIT (Henry Ford Exercise Testing) Project.

Science.gov (United States)

McAuley, Paul A; Keteyian, Steven J; Brawner, Clinton A; Dardari, Zeina A; Al Rifai, Mahmoud; Ehrman, Jonathan K; Al-Mallah, Mouaz H; Whelton, Seamus P; Blaha, Michael J

2018-05-03

To assess the influence of exercise capacity and body mass index (BMI) on 10-year mortality in patients with heart failure (HF) and to synthesize these results with those of previous studies. This large biracial sample included 774 men and women (mean age, 60±13 years; 372 [48%] black) with a baseline diagnosis of HF from the Henry Ford Exercise Testing (FIT) Project. All patients completed a symptom-limited maximal treadmill stress test from January 1, 1991, through May 31, 2009. Patients were grouped by World Health Organization BMI categories for Kaplan-Meier survival analyses and stratified by exercise capacity (<4 and ≥4 metabolic equivalents [METs] of task). Associations of BMI and exercise capacity with all-cause mortality were assessed using multivariable-adjusted Cox proportional hazards models. During a mean follow-up of 10.1±4.6 years, 380 patients (49%) died. Kaplan-Meier survival plots revealed a significant positive association between BMI category and survival for exercise capacity less than 4 METs (log-rank, P=.05), but not greater than or equal to 4 METs (P=.76). In the multivariable-adjusted models, exercise capacity (per 1 MET) was inversely associated, but BMI was not associated, with all-cause mortality (hazard ratio, 0.89; 95% CI, 0.85-0.94; P<.001 and hazard ratio, 0.99; 95% CI, 0.97-1.01; P=.16, respectively). Maximal exercise capacity modified the relationship between BMI and long-term survival in patients with HF, upholding the presence of an exercise capacity-obesity paradox dichotomy as observed over the short-term in previous studies. Copyright © 2018 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Testing the effects of message framing, kernel state, and exercise guideline adherence on exercise intentions and resolve

NARCIS (Netherlands)

de Bruijn, G.J.; Out, K.; Rhodes, R.E.

2014-01-01

Objectives To study the effects of framed messages on exercise intention and resolve. Design Two (type of frame: gain or loss) × 2 (type of kernel state: desirable or undesirable outcome) post-test study. Methods Participants were recruited online and questioned about their previous exercise

Discordance of exercise thallium testing with coronary arteriography in patients with atypical presentations

International Nuclear Information System (INIS)

Bungo, M.W.; Leland, O.S. Jr.

1983-01-01

Eighty-one patients with diagnostically difficult clinical presentations suggesting coronary disease underwent symptom-limited maximal-exercise treadmill testing (ETT) and exercise radionuclide scanning with 201 Tl. Results of these tests were in agreement in only 47 percent of the cases. Either exercise thallium or ETT was positive in 94 percent of patients with disease. Among a population with a disease prevalence of 67 percent, agreement between exercise thallium an ETT predicted disease in 92 percent of instances or excluded disease in 82 percent of instances. Frequent discordance between these two tests in 53 percent of the cases unfortunately limits this usefulness

Thallium-201 exercise myocardial imaging to evaluate myocardial perfusion after coronary artery bypass surgery

International Nuclear Information System (INIS)

Hirzel, H.O.; Nuesch, K.; Sialer, G.; Horst, W.; Krayenbuehl, H.P.

1980-01-01

To assess the usefulness of thallium-201 exercise scintigraphy in evaluating myocardial perfusion after coronary artery bypass surgery, imaging was performed after submaximal bicycle ergometry and at rest in 54 patients before and within 24 +- 10 (SD) weeks after operation. Scintigraphy identified 8 out of 20 patients who were symptom free after operation and showed normal exercise electrocardiograms as still having exercise-induced ischaemia and thus as having not truly benefited from the surgical intervention. In contrast, improvement in perfusion was documented in 17 out of 31 patients despite further complaints of chest pain and persistence of a pathological exercise electrocardiogram in 6 of them. Bypass graft patency rate paralleled the scintigraphic findings in the 35 patients who were restudied arteriographically. It was concluded that thallium-201 exercise scintigraphy is a useful technique to document changes in regional perfusion after surgery and is definitely superior to the clinical evaluation of patients including the exercise electrocardiogram. (author)

Synthesis and biological evaluation of novel dioxa-bicycle C-aryl glucosides as SGLT2 inhibitors.

Science.gov (United States)

Yan, Qi; Ding, Ning; Li, Yingxia

2016-02-08

A series of novel C-aryl glucosides containing dioxa-bicycle were synthesized and evaluated for inhibition activity against hSGLT2. Among the compounds tested, compound 6a showed moderate SGLT2 inhibition activities at 700 nM. The results could benefit the discovery of new SGLT2 inhibitors. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Silent myocardial ischemia and exercise-induced arrhythmia detected by the exercise test in the total health promotion plan (THP)].

Science.gov (United States)

Iwane, M; Shibe, Y; Itoh, K; Kinoshita, F; Kanagawa, Y; Kobayashi, M; Mugitani, K; Ohta, M; Ohata, H; Yoshikawa, A; Ikuta, Z; Nakamura, Y; Mohara, O

2001-03-01

We investigated the prevalence and characteristics of ischemic heart disease especially silent myocardial ischemia (SMI) and arrhythmia in need of careful observation in the exercise stress tests in the Total Health Promotion Plan (THP), which was conducted between 1994-96 for the purpose of measuring cardiopulmonary function. All workers (n = 4,918, 4,426 males) aged 18-60 yr old in an occupational field were studied. Exercise tests with an ergometer were performed by the LOPS protocol, in which the maximal workload was set up as a presumed 70-80% maximal oxygen intake, or STEP (original multistage protocol). ECG changes were evaluated with a CC5 lead. Two hundred and fifteen people refused the study because of a common cold, lumbago and so on. Of 4,703 subjects, 17 with abnormal rest ECG and 19 with probable anginal pain were excluded from the exercise tests. Of 4,667 who underwent the exercise test, 37 (0.79%) had ischemic ECG change, and 155 (3.32%) had striking arrhythmia. These 228 subjects then did a treadmill exercise test with Bruce protocol. Twenty-two (0.47% of 4,703) showed positive ECG change, 9 (0.19%) of 22 had abnormal findings on a 201Tl scan. 8 (0.17%) were diagnosed as SMI (Cohn I), in which the prevalence of hypertension, hyperlipidemia, diabetes mellitus, smoker and positive familial history of ischemic heart disease was greater than that of all subjects. In a 15-30 month follow up, none has developed cardiac accidents. Exercise-induced arrhythmia was detected in 11 (0.23%) subjects. Four were non-sustained ventricular tachycardia without any organic disease, 4 were ventricular arrhythmia based on cardiomyopathy detected by echocardiography, 2 were atrial fibrillation and another was WPW syndrome. It is therefore likely that the ergometer exercise test in THP was effective in preventing sudden death caused by ischemic heart disease or striking arrhythmia.

Mr-Proanp Rises during Exercise Even after Surgical Closure of the Left Atrial Appendage

DEFF Research Database (Denmark)

Hagdrup, Christian; Hansen, Jesper Park; Svendsen, Jesper Hastrup

2017-01-01

bicycle exercise test, at least six weeks after the operation. Closure of the LAA was confirmed by Transesophageal Echocardiography (TEE). Venous blood samples were collected before the test, and within the first two minutes of recovery after maximum work-load. Results: Baseline ANP showed (non-closed vs....... closed LAA): 163.3pM (95% CI: 121.9 – 204.8) vs. 137.5 pM (95% CI: 69.5 – 205.6), p=0.4575. Maximum work-load was similar for both groups. MR-proANP concentration rose significantly: Max ANP (non-closed vs. closed LAA): 197.4pM (95% CI: 146.9 - 247.9) vs. 164.3pM (95% CI: 89.1 - 239.6), p=0.4061MR......-proANP increase was not different between the groups. Delta ANP (non-closed vs. closed LAA): 34.1pM (95% CI: 22.1 – 46.1) vs. 26.8pM (95% CI: 15.3 – 38.3), p=0.3352 Conclusion: This study shows that plasma MR-proANP increases during exercise, and that surgical LAA closure did not reduce the increase of MR...

Essential Amino Acids and Exercise Tolerance in Elderly Muscle-Depleted Subjects with Chronic Diseases: A Rehabilitation without Rehabilitation?

Directory of Open Access Journals (Sweden)

Roberto Aquilani

2014-01-01

Full Text Available Exercise intolerance remains problematic in subjects with chronic heart failure (CHF and/or chronic obstructive pulmonary disease (COPD. Recent studies show that supplemented essential amino acids (EAAs may exert beneficial effects on CHF/COPD physical capacity. The results from 3 investigations (2 conducted on CHF and 1 on COPD subjects served as the basis for this paper. The 3 studies consistently showed that elderly CHF and COPD improved exercise intolerance after 1–3 months of EAA supplementation (8 g/d. In CHF exercise capacity increased 18.7% to 23% (watts; bicycle test, and 12% to 22% (meters in 6 min walking test. Moreover, patients reduced their resting plasma lactate levels (by 25% and improved tissue insulin sensitivity by 16% (HOMA index. COPD subjects enjoyed similar benefits as CHF ones. They increased physical autonomy by 78.6% steps/day and decreased resting plasma lactate concentrations by 23%. EAA mechanisms explaining improved exercise intolerance could be increases in muscle aerobic metabolism, mass and function, and improvement of tissue insulin sensitivity (the latter only for the CHF population. These mechanisms could be accounted for by EAA’s intrinsic physiological activity which increases myofibrils and mitochondria genesis in skeletal muscle and myocardium and glucose control. Supplemented EAAs can improve the physical autonomy of subjects with CHF/COPD.

Effect of bicycle saddle designs on the pressure to the perineum of the bicyclist.

Science.gov (United States)

Lowe, Brian D; Schrader, Steven M; Breitenstein, Michael J

2004-06-01

Increasing awareness of an association between bicycling and male sexual dysfunction has led to the appearance of a variety of bicycle saddles that share the design objective of reducing pressure in the groin of the cyclist by removal of the narrow protruding nose of the saddle. This study compared three of these saddle designs to a traditional sport/road racing saddle with a narrow protruding nose in terms of pressure in the region of the perineum (groin) of the cyclist. Saddle, pedal, and handlebar contact pressure were measured from 33 bicycle police patrol officers pedaling a stationary bicycle at a controlled cadence and workload. Pressure was characterized over the saddle as a whole and over a region of the saddle assumed to represent pressure on the cyclist's perineum located anteriorly to the ischial tuberosities. The traditional sport/racing saddle was associated with more than two times the pressure in the perineal region than the saddles without a protruding nose (P perineum of the bicyclist.

Wireless controller and smartphone based interaction system for electric bicycles.

Directory of Open Access Journals (Sweden)

Jorge REVUELTA HERRERO

2016-07-01

Full Text Available Throughout the last years, great improvements have been made in the automotive industry, a sector with a high impact in both economics and social environments. Many development efforts have targeted on satisfying the need of providing smart environments to the end user in vehicles, such as cars. This paper proposes a brand-new solution in the automotive field, consisting of a new product family which aims to transform the traditional bicycle to an electric bicycle using an architecture that provides an adaptive environment to the user, improving the driving experience enabling value-added services.

Gender differences in the variables of exercise treadmill test in type ...

African Journals Online (AJOL)

Background: Exercise capacity, like some other variables of exercise stress test, is a strong predictor of cardiovascular and overall ..... plan, and guide cardiac rehabilitation. .... peripheral vascular disease, peripheral neuropathy, physical ...

Traumatic Globe Subluxation and Intracranial Injury Caused by Bicycle Brake Handle.

Science.gov (United States)

Poroy, Ceren; Cibik, Cansu; Yazici, Bulent

2016-09-01

Penetration of a bicycle brake handle into the orbit is a rare and serious type of trauma. Globe subluxation due to such trauma has not been previously reported. A 10-year-old girl presented after falling from a bicycle, which resulted in the handbrake penetrating her right upper eyelid. On examination, the globe was subluxated anteriorly, there was no light perception, and the pupilla was fixed and dilated. Radiologic studies revealed orbitonasal fractures, hemorrhage, emphysema in the orbit and cranium, and rupture of the extraocular muscles. The globe was replaced into the orbit with the help of lateral cantholysis and orbital septotomy. During 22 months of follow-up, the globe remained intact, but total loss of vision, blepharoptosis, and extraocular motility restriction persisted. This case and previous reports show that bicycle brake handles can cause severe, penetrating orbital and cerebral traumas that can result in vision loss or fatality. Brake handles should be designed to protect bicyclists from such injuries.

Design Analysis And Applications Of A Regenerative Bicycle Ergometer

Directory of Open Access Journals (Sweden)

Chukwuneke J. L.

2015-08-01

Full Text Available Man needs to do some form of physical work in other to remain healthy this work is similar to the work done by any machine or equipment and thus should be channeled to give useful output but rather it is usually dissipated into the environment in form of heat. The regenerative bicycle ergometer takes advantage of the greater power generated by the limbs and arms thus conserves converts and stores the energy dissipated by the rider with an ideal mechanical advantage of 7.6 it strategically uses simple mechanisms to magnify its work and then converts this mechanical energy into electrical energy by the use of a dynamo with a speed ratio of 108.5 and a transmission efficiency of 89 the rider pedals 27rpm to obtain the dynamos rated input of 2600rpm giving an output of 12.6volts. The regenerative bicycle ergometer is designed and constructed to perform all the core functions of a bicycle ergometer having an allowable load of 116.5kg and a maximum resistance of 65.33N which is equivalent to a mass of 6.66kg. The energy converted is stored in a 12volts battery making its use flexible clean and meeting the energy demands of man.

Negative Exercise Stress Test: Does it Mean Anything? Case study

Directory of Open Access Journals (Sweden)

Hassan A. Mohamed

2007-01-01

Full Text Available Despite its low sensitivity and specificity (67% and 72%, respectively, exercise testing has remained one of the most widely used noninvasive tests to determine the prognosis in patients with suspected or established coronary disease.As a screening test for coronary artery disease, the exercise stress test is useful in that it is relatively simple and inexpensive. It has been considered particularly helpful in patients with chest pain syndromes who have moderate probability for coronary artery disease, and in whom the resting electrocardiogram (ECG is normal. The following case presentation and discussion will question the predictive value of a negative stress testing in patients with moderate probability for coronary artery disease.

The different ways to get on and off a bicycle for young and old

NARCIS (Netherlands)

Dubbeldam, R.; Baten, C. T.M.; Straathof, P.T.C.; Buurke, J. H.; Rietman, J. S.

2017-01-01

In the Netherlands, each year 12,000 older cyclists require medical attention due to a single-bicycle accident where no other party is directly involved. Most of these accidents occur at low cycling velocities and 20% occur during (dis)mounting the bicycle. Little is known about the strategies and

Evaluation of a promotional strategy to increase bicycle helmet use by children.

Science.gov (United States)

Parkin, P C; Spence, L J; Hu, X; Kranz, K E; Shortt, L G; Wesson, D E

1993-04-01

Bicycle-related head injuries are an important cause of death and disability, despite the availability of helmets. The objective of this study was to evaluate the effectiveness of a school-based bicycle helmet promotion program in increasing helmet use by children while controlling for secular trends. Two high-income and two low-income schools in an urban Canadian community were selected to receive a bicycle helmet promotion intervention, with the remaining 18 schools serving as controls. Approximately 1800 observations of bicycling children were made at randomly selected observational sites 2 to 5 months after the intervention to assess changes in behavior. Helmet use at all observation sites tripled from 3.4% (1990, preintervention) to 16% (1991, postintervention). In the high-income intervention area, observed helmet use rose dramatically from 4% to 36% in contrast to the more modest increase in the high-income control area from 4% to 15%. In the low-income intervention area, there was a modest increase from 1% to 7%, but it did not differ from the increase in the low-income control area from 3% to 13%. The program was highly successful in children of high-income families but not in children of low-income families. Developing strategies for low-income families remains a priority.

Effects of a short-term exercise training program on aerobic fitness, fatigue, health perception and activity level of subjects with multiple sclerosis.

Science.gov (United States)

Mostert, S; Kesselring, J

2002-04-01

Multiple sclerosis (MS) patients of an inpatient rehabilitation program have been randomly assigned to an exercise training (MS-ET) or nontraining group (MS-NI). Before and after 4 weeks of aerobic exercise training, a graded maximal exercise test with measurement of gas exchange and a lung function test was administered to all 26 patients fulfilling the inclusion criteria. Activity level, fatigue and health perception were measured by means of questionnaires. Twenty-six healthy persons served as control group and were matched in respect of age, gender and activity level. Training intervention consisted of 5x30 min sessions per week of bicycle exercise with individualised intensity. Compared with baseline, the MS training group demonstrated a significant rightward placement of the aerobic threshold (AT) (VO2+13%; work rate [WR])+11%), an improvement of health perception (vitality+46%; social interaction+36%), an increase of activity level (+17%) and a tendency to less fatigue. No changes were observed for the MS-NI group and the control groups. Maximal aerobic capacity and lung function were not changed by either training or nontraining in all four groups. Overall compliance to the training program was quite low (65%), whereas incidence of symptom exacerbation by physical activity has been lower than expected (6%).

Muscular exercise can cause highly pathological liver function tests in healthy men.

Science.gov (United States)

Pettersson, Jonas; Hindorf, Ulf; Persson, Paula; Bengtsson, Thomas; Malmqvist, Ulf; Werkström, Viktoria; Ekelund, Mats

2008-02-01

The occurrence of idiosyncratic drug hepatotoxicity is a major problem in all phases of clinical drug development and the leading cause of postmarketing warnings and withdrawals. Physical exercise can result in transient elevations of liver function tests. There is no consensus in the literature on which forms of exercise may cause changes in liver function tests and to what extent. Weightlifting results in profound increases in liver function tests in healthy men used to moderate physical activity, not including weightlifting. Liver function tests are significantly increased for at least 7 days after weightlifting. It is important to impose relevant restrictions on heavy muscular exercise prior to and during clinical studies. To investigate the effect of intensive muscular exercise (weightlifting) on clinical chemistry parameters reflecting liver function in healthy men. Fifteen healthy men, used to moderate physical activity not including weightlifting, performed an 1 h long weightlifting programme. Blood was sampled for clinical chemistry parameters [aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LD), gamma-glutamyl transferase (gamma GT), alkaline phosphatase (ALP), bilirubin, creatine kinase (CK) and myoglobin] at repeated intervals during 7 days postexercise and at a follow-up examination 10-12 days postexercise. Five out of eight studied clinical chemistry parameters (AST, ALT, LD, CK and myoglobin) increased significantly after exercise (P exercise. In addition, LD and, in particular, CK and myoglobin showed highly elevated levels. These findings highlight the importance of imposing restrictions on weightlifting prior to and during clinical studies. Intensive muscular exercise, e.g. weightlifting, should also be considered as a cause of asymptomatic elevations of liver function tests in daily clinical practice.

Bicycle Design : A different approach to improving on the world human powered speed records

NARCIS (Netherlands)

Epema, H.K.; Van den Brand, S.; Gregoor, W.; Kooijman, J.D.G.; Pereboom, H.P.; Wielemaker, D.C.; Van der Zweep, C.J.

2012-01-01

The current International Human Powered Vehicle Association world records for faired bicycles stand at 133.284km/h for the 200m flying start speed record and 91.562 km for the hour record. Traditionally the recumbent bicycles that have been developed for breaking one of either of these records have

Genetic testing for exercise prescription and injury prevention: AIS-Athlome consortium-FIMS joint statement.

Science.gov (United States)

Vlahovich, Nicole; Hughes, David C; Griffiths, Lyn R; Wang, Guan; Pitsiladis, Yannis P; Pigozzi, Fabio; Bachl, Nobert; Eynon, Nir

2017-11-14

There has been considerable growth in basic knowledge and understanding of how genes are influencing response to exercise training and predisposition to injuries and chronic diseases. On the basis of this knowledge, clinical genetic tests may in the future allow the personalisation and optimisation of physical activity, thus providing an avenue for increased efficiency of exercise prescription for health and disease. This review provides an overview of the current status of genetic testing for the purposes of exercise prescription and injury prevention. As such there are a variety of potential uses for genetic testing, including identification of risks associated with participation in sport and understanding individual response to particular types of exercise. However, there are many challenges remaining before genetic testing has evidence-based practical applications; including adoption of international standards for genomics research, as well as resistance against the agendas driven by direct-to-consumer genetic testing companies. Here we propose a way forward to develop an evidence-based approach to support genetic testing for exercise prescription and injury prevention. Based on current knowledge, there is no current clinical application for genetic testing in the area of exercise prescription and injury prevention, however the necessary steps are outlined for the development of evidence-based clinical applications involving genetic testing.

Simple exercise test for the prediction of relative heat tolerance

International Nuclear Information System (INIS)

Kenney, W.L.; Lewis, D.A.; Anderson, R.K.; Kamon, E.

1986-01-01

A medical screening exercise test is presented which accurately predicts relative heat tolerance during work in very hot environments. The test consisted of 15-20 min of exercise at a standard absolute intensity of about 600 kcal/hr (140W) with the subject wearing a vapor-barrier suit. Five minutes after the subject exercised, recovery heart rate was measured. When this heart rate is used, a physiological limit (+/- approximately 5 min) can be predicted with 95% confidence for the most intense work-heat conditions found in nuclear power stations. In addition, site health and safety personnel can establish qualification criteria for work on hot jobs, based on the test results. The test as developed can be performed in an office environment with the use of a minimum of equipment by personnel with minimal expertise and training. Total maximal test duration is about 20-25 min per person and only heart rate need be monitored (simple pulse palpation will suffice). Test modality is adaptable to any ergometer, the most readily available and least expensive of which is bench-stepping. It is recommended that this test be available for use for those persons who, based upon routine medical examination or past history, are suspected of being relatively heat intolerant

Modelling mode choice in short trips - shifting from car to bicycle

DEFF Research Database (Denmark)

Halldórsdóttir, Katrín; Christensen, Linda; Jensen, Thomas Christian

2011-01-01

-economic variables of a representative sample of the population. The investigated sample includes 11,072 observations. The model considers five alternatives (i.e., car driver, car passenger, public transport, walk and obviously bike), for which level of service variables are calculated through assignment procedures...... relevance of the cost for short trips. Expectedly, the selection of bicycle as mode for short trips is positively related to owning a bicycle and negatively linked to owning one or more cars. Urban density has also positive correlation with the selection of sustainable transport modes....

Discordance of exercise thallium testing with coronary arteriography in patients with atypical presentations

International Nuclear Information System (INIS)

Bungo, M.W.; Leland, O.S. Jr.

1983-01-01

Eighty-one patients with diagnostically difficult clinical presentations suggesting coronary artery disease underwent symptom-limited maximal-exercise treadmill testing (ETT) and exercise radionuclide scanning with thallium-201 followed by coronary angiography. Results showed that in nearly half of the patients (47%) these tests were in agreement, while either exercise thallium or ETT was positive in 94% of patients with coronary artery disease. It was found that agreement between exercise thallium and ETT tests predicted disease in 92% of the instances or excluded disease in 82% of the instances. It is concluded that despite frequent discord between these two tests in 53% of the cases, a significant gain in exclusive diagnostic capability is realized when applied to a patient population anticipated to have a disease prevalence equal to the 67% encountered in this study

“Bicycles May Use Full Lane” Signage Communicates U.S. Roadway Rules and Increases Perception of Safety

Science.gov (United States)

2015-01-01

Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to “get out of the way” to allow motorists to pass without changing lanes: “Bicycles May Use Full Lane” and “Share the Road” signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. “Bicycles May Use Full Lane” signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. “Share the Road” signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. “Bicycles May Use Full Lane” signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing “Share the Road” with “Bicycles May Use Full Lane” signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited. PMID

Comparison of exercise stress testing with dobutamine stress echocardiography and exercise technetium-99m isonitrile single photon emission computerized tomography for diagnosis of coronary artery disease

International Nuclear Information System (INIS)

Oguzhan, A.; Kisacik, H.L.; Ozdemir, K.

1997-01-01

To compare the value of exercise electrocardiography with dobutamine stress echocardiography and exercise technetium-99m isonitrile single-photon emission computed tomography for coronary artery disease, 70 patients with either suspected or proven coronary artery disease underwent dobutamine stress echocardiography, exercise technetium-99m isonitrile single-photon emission computed tomography (mibi-SPECT) and treadmill exercise electrocardiography (ECG). Dobutamine echocardiography and exercise mibi-SPECT revealed a higher overall sensitivity than exercise testing (90 vs 57%, p 0.05; 90 and 62% p<0.05, respectively) but the difference between dobutamine stress echocardiography and exercise mibi-SPECT was not statistically significant. Diagnostic accuracy of dobutamine stress echocardiography and exercise mibi-SPECT was higher than that of exercise testing (90 vs 59%, p<0.001; 89 vs 59%, p<0.001, respectively). Dobutamine stress echocardiography and exercise mibi-SPECT have superiority over exercise testing in the diagnosis of coronary artery disease and dobutamine stress echocardiography is an alternative for exercise mibi-SPECT. (author)

Maximal exercise testing of men with prostate cancer being treated with androgen deprivation therapy.

Science.gov (United States)

Wall, Bradley A; Galvão, Daniel A; Fatehee, Naeem; Taaffe, Dennis R; Spry, Nigel; Joseph, David; Newton, Robert U

2014-12-01

Exercise is being increasingly established as a key adjuvant therapy in clinical oncology. As research has demonstrated the beneficial effect of exercise for cancer management, a growing number of patients with cancer are undertaking structured exercise programs. This study aimed to determine the safety and feasibility of formal exercise testing in clinical settings as it is becoming increasingly used as a screening tool and for exercise prescription purposes. One hundred and twelve patients with prostate cancer undergoing androgen deprivation therapy (ADT) took part in a physician-supervised multistage maximal stress test (Bruce protocol). Sixty patients had been on ADT for 3 months (chronic). Of these men, 85% were able to meet the criteria for the attainment of V˙O2max, whereas three positive tests (3.2%) were observed. The three participants who recorded a positive stress test underwent further medical examination and were subsequently cleared of clinically significant cardiovascular disease. Apart from the relatively low V˙O2max (24.7 ± 6.0 mL·kg·min, 10th-15th percentile), compared with normative data in healthy age-matched controls, the cardiovascular response to exercise was similar in this cancer population. Moreover, treatment duration did not seem to influence cardiovascular responses to exercise. This early evidence suggests that risk of adverse events during maximal exercise testing is relatively low in this population and certainly no higher than that in ages-matched, apparently healthy individuals. Maximal exercise testing was demonstrated to be feasible and safe, providing a direct assessment of V˙O2max. The relatively low number of positive tests in this study suggests that the risk of adverse events is relatively low in this population and certainly no higher than that in age-matched, apparently healthy individuals.

Allene functionalization via bicyclic methylene aziridines.

Science.gov (United States)

Boralsky, Luke A; Marston, Dagmara; Grigg, R David; Hershberger, John C; Schomaker, Jennifer M

2011-04-15

The oxidative functionalization of olefins is a common method for the formation of vicinal carbon-heteroatom bonds. However, oxidative methods to transform allenes into synthetic motifs containing three contiguous carbon-heteroatom bonds are much less developed. This paper describes the use of bicyclic methylene aziridines (MAs), prepared via intramolecular allene aziridination, as scaffolds for functionalization of all three allene carbons. © 2011 American Chemical Society

Latent segmentation based count models: Analysis of bicycle safety in Montreal and Toronto.

Science.gov (United States)

Yasmin, Shamsunnahar; Eluru, Naveen

2016-10-01

The study contributes to literature on bicycle safety by building on the traditional count regression models to investigate factors affecting bicycle crashes at the Traffic Analysis Zone (TAZ) level. TAZ is a traffic related geographic entity which is most frequently used as spatial unit for macroscopic crash risk analysis. In conventional count models, the impact of exogenous factors is restricted to be the same across the entire region. However, it is possible that the influence of exogenous factors might vary across different TAZs. To accommodate for the potential variation in the impact of exogenous factors we formulate latent segmentation based count models. Specifically, we formulate and estimate latent segmentation based Poisson (LP) and latent segmentation based Negative Binomial (LNB) models to study bicycle crash counts. In our latent segmentation approach, we allow for more than two segments and also consider a large set of variables in segmentation and segment specific models. The formulated models are estimated using bicycle-motor vehicle crash data from the Island of Montreal and City of Toronto for the years 2006 through 2010. The TAZ level variables considered in our analysis include accessibility measures, exposure measures, sociodemographic characteristics, socioeconomic characteristics, road network characteristics and built environment. A policy analysis is also conducted to illustrate the applicability of the proposed model for planning purposes. This macro-level research would assist decision makers, transportation officials and community planners to make informed decisions to proactively improve bicycle safety - a prerequisite to promoting a culture of active transportation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bicycle Frame Prediction Techniques with Fuzzy Logic Method

Directory of Open Access Journals (Sweden)

Rafiuddin Syam

2015-03-01

Full Text Available In general, an appropriate size bike frame would get comfort to the rider while biking. This study aims to predict the simulation system on the bike frame sizes with fuzzy logic. Testing method used is the simulation test. In this study, fuzzy logic will be simulated using Matlab language to test their performance. Mamdani fuzzy logic using 3 variables and 1 output variable intake. Triangle function for the input and output. The controller is designed in the type mamdani with max-min composition and the method deffuzification using center of gravity method. The results showed that height, inseam and Crank Size generating appropriate frame size for the rider associated with comfort. Has a height range between 142 cm and 201 cm. Inseam has a range between 64 cm and 97 cm. Crank has a size range between 175 mm and 180 mm. The simulation results have a range of frame sizes between 13 inches and 22 inches. By using the fuzzy logic can be predicted the size frame of bicycle suitable for the biker.

Bicycle Frame Prediction Techniques with Fuzzy Logic Method

Directory of Open Access Journals (Sweden)

Rafiuddin Syam

2017-03-01

Full Text Available In general, an appropriate size bike frame would get comfort to the rider while biking. This study aims to predict the simulation system on the bike frame sizes with fuzzy logic. Testing method used is the simulation test. In this study, fuzzy logic will be simulated using Matlab language to test their performance. Mamdani fuzzy logic using 3 variables and 1 output variable intake. Triangle function for the input and output. The controller is designed in the type mamdani with max-min composition and the method deffuzification using center of gravity method. The results showed that height, inseam and Crank Size generating appropriate frame size for the rider associated with comfort. Has a height range between 142 cm and 201 cm. Inseam has a range between 64 cm and 97 cm. Crank has a size range between 175 mm and 180 mm. The simulation results have a range of frame sizes between 13 inches and 22 inches. By using the fuzzy logic can be predicted the size frame of bicycle suitable for the biker.

Conversion Of An Ordinary N Bicycle Into An Electric Bike And Related Research

Directory of Open Access Journals (Sweden)

Marius Janavičius

2014-05-01

Full Text Available An electric bicycle as a transport and leisure vehicle is expected to have a promising future. Currently, he market offers a great choice of factory electric bicycles and conversion kits to remake an ordinary bicycle into an electric bike. Also, the increasing number of electric vehicles is determined by the reduction in costs for manufacturing of batteries and an evolution in battery technology. This article presents the implementation of an electric bike by selecting the “Golden Motor Technology” company’s electric front wheel conversion kit MagicPie3 and 16 cell 10Ah LiFePO4 battery. After installation of the engine and other components, experiments were conducted to evaluate the performance characteristics of the electric bike and check the manufacturer’s specifications.

Ventricular performance during exercise in patients with chronic obstructive pulmonary disease (COPD)

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Iwao; Akashiba, Tsuneto; Horie, Takashi [Nihon Univ., Tokyo (Japan). School of Medicine

1992-01-01

We assessed ventricular performance during exercise in 16 chronic obstructive pulmonary disease (COPD) patients and 8 normal control subjects by means of radionuclide equilibrium angiography using technetium-99m as a tracer. Supine exercise on a bicycle ergometer was performed until symptom-limited exhaustion. Data were accumulated for 300 heart beats at rest and 150 heart beats during exercise. We used the standard voxel count method to calculate the ventricular volumes. Age, FEV{sub 1.0}%, %VC, PaO{sub 2} and PaCO{sub 2} of the COPD patients were 63{+-}8 yr, 46{+-}11%, 69{+-}18%, 68{+-}11 Torr and 44{+-}7 Torr (mean{+-}SD), respectively. Systolic dysfunction of both the left and right ventricles was well confirmed in the present study. In 12 patients who also underwent hemodynamic studies, resting total pulmonary vascular resistance index (TPVRI) and mean pulmonary artery pressure (P-barpa) significantly correlated with right ventricular end-systolic volume index (RVESVI) obtained by RI angiography; {gamma}=0.769 (p<0.01) and {gamma}=0.631 (p<0.05), respectively. A significant relationship was also observed between left ventricular dysfunction and the degree of hypercapnia. In response to exercise testing, 10 of 16 patients exhibited insufficient augmentation of stroke volume, and both left and right end-diastolic volumes decreased in half of 10 patients. It is suggested that cardiac function may be disturbed by mechanical factors such as pulmonary hyperinflation in COPD patients. (author).

The pacing stress test: thallium-201 myocardial imaging after atrial pacing. Diagnostic value in detecting coronary artery disease compared with exercise testing

International Nuclear Information System (INIS)

Heller, G.V.; Aroesty, J.M.; Parker, J.A.; McKay, R.G.; Silverman, K.J.; Als, A.V.; Come, P.C.; Kolodny, G.M.; Grossman, W.

1984-01-01

Many patients suspected of having coronary artery disease are unable to undergo adequate exercise testing. An alternate stress, pacing tachycardia, has been shown to produce electrocardiographic changes that are as sensitive and specific as those observed during exercise testing. To compare thallium-201 imaging after atrial pacing stress with thallium imaging after exercise stress, 22 patients undergoing cardiac catheterization were studied with both standard exercise thallium imaging and pacing thallium imaging. Positive ischemic electrocardiographic changes (greater than 1 mm ST segment depression) were noted in 11 of 16 patients with coronary artery disease during exercise, and in 15 of the 16 patients during atrial pacing. One of six patients with normal or trivial coronary artery disease had a positive electrocardiogram with each test. Exercise thallium imaging was positive in 13 of 16 patients with coronary artery disease compared with 15 of 16 patients during atrial pacing. Three of six patients without coronary artery disease had a positive scan with exercise testing, and two of these same patients developed a positive scan with atrial pacing. Of those patients with coronary artery disease and an abnormal scan, 85% showed redistribution with exercise testing compared with 87% during atrial pacing. Segment by segment comparison of thallium imaging after either atrial pacing or exercise showed that there was a good correlation of the location and severity of the thallium defects (r . 0.83, p . 0.0001, Spearman rank correlation). It is concluded that the location and presence of both fixed and transient thallium defects after atrial pacing are closely correlated with the findings after exercise testing

Diagnostic value of exercise thallium-201 scintigraphy for ischemic heart disease in patients with chronic renal failure

International Nuclear Information System (INIS)

Sato, Shigeaki; Ohta, Makoto; Soejima, Michimasa

1991-01-01

Recently, it has been reported that there are considerable difficulties in diagnosing ischemic heart disease by ECG alone in patients on hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD). This study was designed to evaluate the diagnostic value of exercise thollium-201 myocardial scintigraphy as compared with ECG examination alone in patients with chronic renal failure. The subjects were 26 patients with chronic renal failure, including patients being treated with HD and CAPD, and 7 normal persons who served as controls. Exercise thallium-201 myocardial scintigraphy was performed according to a multistage bicycle ergometer exercise test. Exercise duration times were shorter (p<0.001) and maximum attained heart rates lower (p<0.05) in the HD group than in controls. Since exercise capacities were reduced in the dialysis patients, there were considerable difficulties in diagnosing ischemic heart disease by ECG alone. In our 26 patients, 15 cases (57.7%) had left ventricular hypertrophy, 5 cases (19.2%) had manifestations of ischemic heart disease, and 4 cases with abnormal ECGs had no abnormal findings on exercise thallium-201 myocardial scintigraphy. Thallium washout rates were higher (p<0.001) in the chronic renal failure group than in the control group, and a significant negative correlation (r=-0.70, p<0.001) was found between thallium washout rates and hematocrit values. Exercise thallium-201 myocardial scitigraphy was more accurate than ECG examination and also could be performed repeatedly without invasion. These results indicate that exercise thallium-201 myocardial scintigraphy is a valuable diagnostic method for ischemic heart disease in patients with chronic renal failure. (author)

Plasma ghrelin levels during exercise - effects of intensity and duration.

Science.gov (United States)

Erdmann, Johannes; Tahbaz, Rana; Lippl, Florian; Wagenpfeil, Stefan; Schusdziarra, Volker

2007-10-04

Ghrelin, a recently discovered hormone of gastric origin has been shown to stimulate appetite and food intake. In man it is considered to play a role in energy homeostasis and regulation of somatropic function. As exercise affects hunger/satiety sensations and food intake, at least under some experimental conditions, we investigated the effect of exercise intensity and duration on ghrelin release and subsequent ad libitum food intake in normal weight subjects. Bicycle exercise on an ergometer for 30 min at 50 W which was below the aerob-anaerobic threshold led to an increase of ghrelin which remained unchanged during the higher intensity at 100 W. Respective hunger/satiety ratings and subsequent food intake and postprandial ghrelin suppression were identical and not different from controls. In a second group 7 subjects cycled at 50 W for 30, 60 and 120 min, respectively. Ghrelin concentrations rose significantly by 50-70 pg/ml above baseline for the respective period of exercise. While postexercise premeal ghrelin levels were not significantly different subsequent food intake after 120 min of cycling was significantly greater compared to control, 30 min and 60 min exercise, respectively. The present data suggest that low rather than high-intensity exercise stimulates ghrelin levels independent of exercise duration. Stimulation of food intake during prolonged exercise is most likely not due to changes of ghrelin.

Injuries to Cyclists due to a Dog-Bicycle Interaction.

Science.gov (United States)

Loder, Randall T; Yaacoub, Alan P

2018-05-01

 Both dogs and bicycles are common in our society and thus a dog-bicycle interaction resulting in an injury to a cyclist is possible. It was the purpose of this study to investigate such injuries.  The National Electronic Injury Surveillance System (NEISS) data for the 10-year period from 2006 through 2015 associated with bicycles were accessed. Injuries involving dogs were identified and the mechanism of injury determined. Due to the stratified and weighted nature of the NEISS data, statistical analyses were performed with SUDAAN 10 software (RTI International, Research Triangle Park, North Carolina, United States). A p  dogs were involved in 35,254 (0.67%) cases. The average age for those involved with a dog was 33.2 years and it was 25.5 years for those in which dogs were not involved. There were more females in the dog group (34.1 vs. 27.6%). Dog involvement increased from ages 0 to 14 years, then decreased until the age of 20 years and then progressively increased. Dog-associated injuries most frequently occurred away from home, involved the knee and distal lower extremity, 49.1% sustaining dog bites. Dog bites were more common in younger individuals. Four injury mechanisms (chased by a dog, hit/collided with a dog, swerved/tried to avoid a dog or riding with a dog) accounted for 97.5% of the injuries. Those chased by a dog were younger, more commonly released from the emergency department, had an injury involving the lower extremity and frequently sustained a bite. The most severe injuries were in those who swerved/tried to avoid a dog or hit a dog.  Approximately 1% of injuries to bicyclists are associated with dogs; one-half sustained a bite. Potential/proposed prevention strategies could be educational materials regarding bicycles and dogs to owners, dog restraint, student/parent education and educational materials in waiting rooms of veterinarians, paediatricians, family practice physicians and emergency rooms. Schattauer GmbH Stuttgart.

Investigation of Influential Factors for Bicycle Crashes Using a Spatiotemporal Model

Science.gov (United States)

Gill, G.; Sakrani, T.; Cheng, W.; Zhou, J.

2017-09-01

Despite the numerous potential advantages of indulging in bicycling, such as elevation of health and environment along with mitigation of congestion, the cyclists are a vulnerable group of commuters which is exposed to safety risks. This study aims to investigate the explanatory variables at transportation planning level which have a significant impact on the bicycle crashes. To account for the serial changes around the built environment, the linear time trend as well as time-varying coefficients are utilized for the covariates. These model modifications help account for the variations in the environment which may escape the incorporated variables due to lack of robustness in data. Also, to incorporate the interaction of roadway, demographic, and socioeconomic features within a Traffic Analysis Zone (TAZ), with the bicycle crashes of that area, a spatial correlation is integrated. This spatial correlation accounts for the spatially structured random effects which capture the unobserved heterogeneity and add towards building more comprehensive model with relatively precise estimates. Two different age groups, the student population in the TAZs, the presence of arterial roads and bike lanes, were observed to be statistically significant variables related with bicycle crashes. These observations will guide the transportation planning organizations which focus on the entity of TAZ while developing policies. The results of the current study establish a quantifies relationship between the significant factors and the crash count which will enable the planners to choose the most cost-efficient, yet most productive, factors which needs to be addressed for mitigation of crashes.

A strategic approach to [6,6]-bicyclic lactones

DEFF Research Database (Denmark)

Jepsen, Tue Heesgaard; Glibstrup, Emil; Crestey, Francois Louis Jean

2017-01-01

We report an effective synthetic protocol to access [6,6]-bicyclic lactone moieties through a regio- and stereoselective intramolecular Mizoroki–Heck cross-coupling reaction followed by a 6π-electrocyclization. This method enabled the first synthesis of the elusive CD fragment of the Erythrina...

The effect of exercise in clinically depressed adults: systematic review and meta-analysis of randomized controlled trials

DEFF Research Database (Denmark)

Krogh, Jesper; Nordentoft, Merete; Sterne, Jonathan A C

2011-01-01

these, the estimated beneficial effect of exercise was more modest (SMD, -0.19; 95% CI, -0.70 to 0.31) than the pooled result for all 13 studies, with no strong evidence of benefit. CONCLUSIONS: Our results suggest a short-term effect of exercise on depression: on average, depression scores 0......OBJECTIVE: To assess the effectiveness of exercise in adults with clinical depression. DATA SOURCES: The databases CINAHL, Embase, Cochrane Database of Systematic reviews, Cochrane Controlled Trials Register, MEDLINE, and PsycINFO were searched (1806-2008) using medical subject headings (Me......SH) and text word terms depression, depressive disorder and exercise, aerobic, non-aerobic, physical activity, physical fitness, walk*, jog*, run*, bicycling, swim*, strength, and resistance. STUDY SELECTION: Randomized trials including adults with clinical depression according to any diagnostic system were...

Synthesis of bicyclic alkaloids from the iridoid antirrhinoside

DEFF Research Database (Denmark)

Frederiksen, Signe Maria

The present thesis describes the isolation of the iridoid glucoside antirrhinoside from Antirrhinum majus, and the approaches made towards its transformation into analogues of biologically active compounds, with special interest in syntheses of bicyclic alkaloids.A synthetic piperidine monoterpene...... or by reduction using lithium aluminum hydride. The piperidines were subjected to hydrogenation to remove the N-benzyl group. The compounds were tested for hypoglycaemic activity by Novo Nordisk, but no activity was observed.Another approach towards a synthetic piperidine monoterpene was attempted. The strategy...... involved preparation of a diol, which through treatment of its ditosyl derivative with an amine would afford a piperidine monoterpene. Antirrhinoside was protected as its 5,6-O-monoacetonide via its 5,6:4',6'-O-diacetonide. The 5,6-O-isopropylidene-derivative was hydrogenated to give the 3,4-dihydro...

Modeling Mixed Bicycle Traffic Flow: A Comparative Study on the Cellular Automata Approach

Directory of Open Access Journals (Sweden)

Dan Zhou

2015-01-01

Full Text Available Simulation, as a powerful tool for evaluating transportation systems, has been widely used in transportation planning, management, and operations. Most of the simulation models are focused on motorized vehicles, and the modeling of nonmotorized vehicles is ignored. The cellular automata (CA model is a very important simulation approach and is widely used for motorized vehicle traffic. The Nagel-Schreckenberg (NS CA model and the multivalue CA (M-CA model are two categories of CA model that have been used in previous studies on bicycle traffic flow. This paper improves on these two CA models and also compares their characteristics. It introduces a two-lane NS CA model and M-CA model for both regular bicycles (RBs and electric bicycles (EBs. In the research for this paper, many cases, featuring different values for the slowing down probability, lane-changing probability, and proportion of EBs, were simulated, while the fundamental diagrams and capacities of the proposed models were analyzed and compared between the two models. Field data were collected for the evaluation of the two models. The results show that the M-CA model exhibits more stable performance than the two-lane NS model and provides results that are closer to real bicycle traffic.

Prognostic value of exercise capacity among patients with treated depression: The Henry Ford Exercise Testing (FIT) Project.

Science.gov (United States)

Ahmed, Amjad M; Qureshi, Waqas T; Sakr, Sherif; Blaha, Michael J; Brawner, Clinton A; Ehrman, Jonathan K; Keteyian, Steven J; Al-Mallah, Mouaz H

2018-04-01

Exercise capacity is associated with survival in the general population. Whether this applies to patients with treated depression is not clear. High exercise capacity remains associated with lower risk of all-cause mortality (ACM) and nonfatal myocardial infraction (MI) among patients with treated depression. We included 5128 patients on antidepressant medications who completed a clinically indicated exercise stress test between 1991 and 2009. Patients were followed for a median duration of 9.4 years for ACM and 4.5 years for MI. Exercise capacity was estimated in metabolic equivalents of tasks (METs). Cox proportional hazards regression models were used. Patients with treated depression who achieved ≥12 METs (vs those achieving model, exercise capacity was associated with a lower ACM (HR per 1-MET increase in exercise capacity: 0.82, 95% CI: 0.79-0.85, P capacity had an inverse association with both ACM and nonfatal MI in patients with treated depression, independent of cardiovascular risk factors. These results highlight the potential impact of assessing exercise capacity to identify risk, as well as promoting an active lifestyle among treated depression patients. © 2018 Wiley Periodicals, Inc.

Testing the effects of message framing, kernel state, and exercise guideline adherence on exercise intentions and resolve.

Science.gov (United States)

de Bruijn, Gert-Jan; Out, Kim; Rhodes, Ryan E

2014-11-01

To study the effects of framed messages on exercise intention and resolve. Two (type of frame: gain or loss) × 2 (type of kernel state: desirable or undesirable outcome) post-test study. Participants were recruited online and questioned about their previous exercise behaviour and their exercise risk perception. After this, they were randomly allocated to one of four messages that were different in terms of positive or negative outcomes (type of frame) and in terms of attained or avoided outcomes (type of kernel state). After reading the message, participants indicated their intention and resolve to engage in sufficient exercise. No effects were found for intention. For resolve, there was a significant interaction between type of frame, type of kernel state, and exercise adherence. Those who did not adhere to the exercise guideline and read the loss-framed message with attained outcomes reported significantly higher resolve than all other participants. This study indicates the relevance of including attained outcomes in message framing exercise interventions as well as a focus on exercise resolve. What is already known on this subject? Message framing is commonly used to increase exercise intentions and behaviour. Meta-analyses do not provide consistent support for this theory. Very little attention has been paid to resolve and message factors on framing effects. What does this study add? Framed messages have an effect on exercise resolve, but not on intention. Loss-framed messages with attained outcomes are most persuasive for those who do not adhere to exercise guidelines. Exercise framing studies should include behavioural resolve next to intention. . © 2014 The British Psychological Society.

Exercise tolerance during VO2max testing is a multifactorial psychobiological phenomenon.

Science.gov (United States)

Midgley, Adrian W; Earle, Keith; McNaughton, Lars R; Siegler, Jason C; Clough, Peter; Earle, Fiona

2017-01-01

Fifty-nine men completed a VO 2max test and a questionnaire to establish reasons for test termination, perceived exercise reserve (difference between actual test duration and the duration the individual perceived could have been achieved if continued until physical limitation), and perception of verbal encouragement. Participants gave between 1 and 11 factors as reasons for test termination, including leg fatigue, various perceptions of physical discomfort, safety concerns, and achievement of spontaneously set goals. The two most common main reasons were leg fatigue and breathing discomfort, which were predicted by pre-to-post test changes in pulmonary function (p = 0.038) and explosive leg strength (p = 0.042; R 2  = 0.40). Median (interquartile range) perceived exercise reserve, was 45 (50) s. Two-thirds of participants viewed verbal encouragement positively, whereas one-third had a neutral or negative perception. This study highlights the complexity of exercise tolerance during VO 2max testing and more research should explore these novel findings.

Harvesting energy from the counterbalancing (weaving) movement in bicycle riding.

Science.gov (United States)

Yang, Yoonseok; Yeo, Jeongjin; Priya, Shashank

2012-01-01

Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power.

Diagnostic value of R wave amplitude changes during exercise testing after myocardial infarction

NARCIS (Netherlands)

de Hert, S.; Vrints, C.; Vanagt, E.; Snoeck, J.

1986-01-01

To determine the diagnostic value of R wave amplitude changes occurring during exercise testing after myocardial infarction, exercise ECG's and coronary angiograms were reviewed in 76 postinfarction patients and in 40 patients with normal coronary arteries. During exercise, an increase in R wave

Central hemodynamic responses during serial exercise tests in heart failure patients using implantable hemodynamic monitors.

Science.gov (United States)

Ohlsson, A; Steinhaus, D; Kjellström, B; Ryden, L; Bennett, T

2003-06-01

Exercise testing is commonly used in patients with congestive heart failure for diagnostic and prognostic purposes. Such testing may be even more valuable if invasive hemodynamics are acquired. However, this will make the test more complex and expensive and only provides information from isolated moments. We studied serial exercise tests in heart failure patients with implanted hemodynamic monitors allowing recording of central hemodynamics. Twenty-one NYHA Class II-III heart failure patients underwent maximal exercise tests and submaximal bike or 6-min hall walk tests to quantify their hemodynamic responses and to study the feasibility of conducting exercise tests in patients with such devices. Patients were followed for 2-3 years with serial exercise tests. During maximal tests (n=70), heart rate increased by 52+/-19 bpm while S(v)O(2) decreased by 35+/-10% saturation units. RV systolic and diastolic pressure increased 29+/-11 and 11+/-6 mmHg, respectively, while pulmonary artery diastolic pressure increased 21+/-8 mmHg. Submaximal bike (n=196) and hall walk tests (n=172) resulted in S(v)O(2) changes of 80 and 91% of the maximal tests, while RV pressures ranged from 72 to 79% of maximal responses. An added potential value of implantable hemodynamic monitors in heart failure patients may be to quantitatively determine the true hemodynamic profile during standard non-invasive clinical exercise tests and to compare that to hemodynamic effects of regular exercise during daily living. It would be of interest to study whether such information could improve the ability to predict changes in a patient's clinical condition and to improve tailoring patient management.

Rest and exercise ventricular function in adults with congenital ventricular septal defects

International Nuclear Information System (INIS)

Jablonsky, G.; Hilton, J.D.; Liu, P.P.; Morch, J.E.; Druck, M.N.; Bar-Shlomo, B.Z.; McLaughlin, P.R.

1983-01-01

Rest and exercise right and left ventricular function were compared using equilibrium gated radionuclide angiography in 19 normal sedentary control subjects and 34 patients with hemodynamically documented congenital ventricular septal defect (VSD). Gated radionuclide angiography was performed at rest and during each level of graded supine bicycle exercise to fatigue. Heart rate, blood pressure, maximal work load achieved, and right and left ventricular ejection fractions were assessed. The control subjects demonstrated an increase in both the left and right ventricular ejection fractions with exercise. All study groups failed to demonstrate an increase in ejection fraction in either ventricle with exercise. Furthermore, resting left ventricular ejection fraction in Groups 2 and 3 was lower than that in the control subjects and resting right ventricular ejection fraction was lower in Group 3 versus control subjects. Thus left and right ventricular function on exercise were abnormal in patients with residual VSD as compared with control subjects; rest and exercise left ventricular ejection fractions remained abnormal despite surgical closure of VSD in the remote past; resting left and right ventricular function was abnormal in patients with Eisenmenger's complex; lifelong volume overload may be detrimental to myocardial function

Redistribution of whole-body energy metabolism by exercise. A positron emission tomography study

International Nuclear Information System (INIS)

Masud, M.M.; Miyake, Masayasu; Watanuki, Shoichi; Itoh, Masatoshi; Tashiro, Manabu; Fujimoto, Toshihiko

2009-01-01

Our aim was to evaluate changes in glucose metabolism of skeletal muscles and viscera induced by different workloads using 18 F-2-fluoro-2-deoxyglucose ([ 18 F]FDG) and three-dimensional positron emission tomography (3-D PET). Five male volunteers performed ergometer bicycle exercise for 40 min at 40% and 70% of the maximal O 2 consumption (VO 2max ). [ 18 ]FDG was injected 10 min later following the exercise task. Whole-body 3-D PET was performed. Five other male volunteers were studied as a control to compare with the exercise group. The PET image data were analyzed using manually defined regions of interest to quantify the regional metabolic rate of glucose (rMRGlc). Group comparisons were made using analysis of variance, and significant differences (P 18 F]FDG-PET can be used as an index of organ energy metabolism for moderate exercise workloads (70% VO 2max ). The results of this investigation may contribute to sports medicine and rehabilitation science. (author)

BUGS at work : a bicycle user group guide

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-07-01

This guide provides practical advice to cyclists on how start a Bicycle User Group (BUG) at their workplace. It offers tools to encourage employers to be proactive in improving facilities in support of cycle commuting. Several BUGs across Canada have worked towards getting better bicycle parking, lockers and shower facilities at their workplace. Other incentives include policies such as flexible work hours for cyclist commuters; casual dress on Friday; reimbursement for the subsidized cost of free parking provided by employers; and, use of a company car if needed for company business during the work day. The advantages to employers include: reduced health care costs because cyclists are physically fit; decreased absenteeism; increased productivity; reduced parking costs; lower company transportation bills; and, a greener corporate image. BUGs provide cycling information ranging from cycling maps to pamphlets and they raise cycle awareness. This guide includes cycling survey samples and examples of successful BUG activities across Canada. refs., tabs., figs.

Children's Perception of Gap Affordances: Bicycling Across Traffic-Filled Intersections in an Immersive Virtual Environment

Science.gov (United States)

Plumert, Jodie M.; Kearney, Joseph K.; Cremer, James F.

2004-01-01

This study examined gap choices and crossing behavior in children and adults using an immersive, interactive bicycling simulator. Ten- and 12-year-olds and adults rode a bicycle mounted on a stationary trainer through a virtual environment consisting of a street with 6 intersections. Participants faced continuous cross traffic traveling at 25mph…

Gender-related difference in arterial elastance during exercise in patients with hypertension.

Science.gov (United States)

Park, Sungha; Ha, Jong-Won; Shim, Chi Young; Choi, Eui-Young; Kim, Jin-Mi; Ahn, Jeong-Ah; Lee, Se-Wha; Rim, Se-Joong; Chung, Namsik

2008-04-01

Exercise intolerance and heart failure with preserved ejection fraction are common in females. Recently, arterial stiffness has been suggested to be a significant contributor in the development of heart failure. How gender difference affects arterial stiffening and its response to exercise is not well known. We hypothesized that arterial elastance index during exercise would be more abnormal in females with hypertension than males. Arterial elastance index was estimated as arterial end systolic pressure/stroke volume controlled for body surface area and was measured at rest and during graded supine bicycle exercise (25 watts, 3-minute increments) in 298 patients with hypertension (149 males; 149 females; mean age, 59). The subjects were divided into 2 groups by gender. Exercise duration was significantly shorter in females compared to males (692+/-222 versus 483+/-128 seconds, Pexercise being significantly higher in females compared to males (0.69+/-0.83 versus 0.43+/-0.69, P=0.018). Arterial elastance index at each stage of exercise up to 75 W was independently associated with decreased exercise duration. In conclusion, despite lower arterial elastance index at rest, the increase during exercise was steeper in women with hypertension, suggesting a gender-related difference in dynamic arterial stiffness. The arterial elastance index during exercise was significantly associated with exercise duration in patients with hypertension.

Clinical test responses to different orthoptic exercise regimes in typical young adults.

Science.gov (United States)

Horwood, Anna; Toor, Sonia

2014-03-01

The relative efficiency of different eye exercise regimes is unclear, and in particular the influences of practice, placebo and the amount of effort required are rarely considered. This study measured conventional clinical measures following different regimes in typical young adults. A total of 156 asymptomatic young adults were directed to carry out eye exercises three times daily for 2 weeks. Exercises were directed at improving blur responses (accommodation), disparity responses (convergence), both in a naturalistic relationship, convergence in excess of accommodation, accommodation in excess of convergence, and a placebo regime. They were compared to two control groups, neither of which were given exercises, but the second of which were asked to make maximum effort during the second testing. Instruction set and participant effort were more effective than many exercises. Convergence exercises independent of accommodation were the most effective treatment, followed by accommodation exercises, and both regimes resulted in changes in both vergence and accommodation test responses. Exercises targeting convergence and accommodation working together were less effective than those where they were separated. Accommodation measures were prone to large instruction/effort effects and monocular accommodation facility was subject to large practice effects. Separating convergence and accommodation exercises seemed more effective than exercising both systems concurrently and suggests that stimulation of accommodation and convergence may act in an additive fashion to aid responses. Instruction/effort effects are large and should be carefully controlled if claims for the efficacy of any exercise regime are to be made. © 2014 The Authors Ophthalmic & Physiological Optics published by John Wiley & Sons Ltd on behalf of The College of Optometrists.

Cell-derived microparticles promote coagulation after moderate exercise.

Science.gov (United States)

Sossdorf, Maik; Otto, Gordon P; Claus, Ralf A; Gabriel, Holger H W; Lösche, Wolfgang

2011-07-01

Cell-derived procoagulant microparticles (MP) might be able to contribute to exercise-induced changes in blood hemostasis. This study aimed to examine (i) the concentration and procoagulant activity of cell-derived MP after a moderate endurance exercise and (ii) the differences in the release, clearance, and activity of MP before and after exercise between trained and untrained individuals. All subjects performed a single bout of physical exercise on a bicycle ergometer for 90 min at 80% of their individual anaerobic threshold. MP were identified and quantified by flow cytometry measurements. Procoagulant activity of MP was measured by a prothrombinase activity assay as well as tissue factor-induced fibrin formation in MP-containing plasma. At baseline, no differences were observed for the absolute number and procoagulant activities of MP between trained and untrained subjects. However, trained individuals had a lower number of tissue factor-positive monocyte-derived MP compared with untrained individuals. In trained subjects, exercise induced a significant increase in the number of MP derived from platelets, monocytes, and endothelial cells, with maximum values at 45 min after exercise and returned to basal levels at 2 h after exercise. Untrained subjects revealed a similar increase in platelet-derived MP, but their level was still increased at 2 h after exercise, indicating a reduced clearance compared with trained individuals. Procoagulant activities of MP were increased immediately after exercise and remained elevated up to 2 h after exercise. We conclude that increased levels of MP were found in healthy individuals after an acute bout of exercise, that the amount of circulating MP contributes to an exercise-induced increase of hemostatic potential, and that there were differences in kinetic and dynamic characteristics between trained and untrained individuals.

Usefulness of exercise ECG test with nitroglycerin and exercise cardiac scintigraphy in patients with false positive exercise ECG test

International Nuclear Information System (INIS)

Moritani, Kohshiro

1984-01-01

The purpose of this study is to evaluate the clinical usefulness of exercise (Ex) ECG test with sublingual nitroglycerin (NTG) and Ex cardiac scintigraphy in differentiating false positive responses from true positive responses of Ex ECG test. We examined 7 pts (age : 46+-7 years) with true positive Ex ECG test (TP) and 8 pts (age : 55+-10 years) with false positive Ex ECG test (FP). TP had significant coronary artery disease and FP did not. Ex test was done by multistage ergometer test. In 5 pts of TP and all pts of FP, Ex cardiac scintigraphy was performed. In TP, Ex cardiac scintigraphy revealed reversible perfusion deficit, but not in FP. NTG was administered 3 minutes before Ex test was started. Ex test with NTG was terminated at the same load as Ex test without NTG. Pressure-rate products at the end point of Ex test did not show significant difference between Ex test without NTG and that with NTG (TP: 203x10 2 , 213x10 2 , FP: 196x10 2 , 206x10 2 , respectively). In 7 pts of FP, ST depression in Ex test without NTG was not improved in Ex test with NTG. On the other hand, in all pts of TP, ST depression seen in Ex test without NTG, was not observed in Ex test with NTG. It may be concluded that Ex cardiac scintigraphy is diagnostic for differentiation of false positive responses from true positive responses of Ex ECG test, as well as Ex ECG test with NTG is. (author)

Usefulness of the cardiopulmonary exercise testing in the asses of unexplained dyspnoea

International Nuclear Information System (INIS)

Benavides L, Herney

2009-01-01

Dyspnoea is a frequent presenting complaint. The assess of this symptom is problematic when its cause is unknown once the initial diagnosis tests are done. Cardiopulmonary exercise testing is an important clinical tool to evaluate dyspnoea as it provides an approach to the integrative exercise responses involving all the organ systems. This would not be possible to reflect by means of individual studies.

Compliance to Standard Equipment Requirements by Exercise Therapy/Fitness Outfits in The South-South Geopolitical Zone of Nigeria

Directory of Open Access Journals (Sweden)

Oluwaseun S. Kubeyinje

2016-08-01

Full Text Available The purpose of this study was to assess the compliance of exercise therapy/fitness outfits in the south-south geopolitical zone of Nigeria to standard equipment requirements. Descriptive survey design was adopted for the conduct of the study using a sample size of 51centres/managers purposively selected from a population of 102 managers of fitness outfits in the six states of the south-south geopolitical zone of Nigeria. A self- developed structured questionnaire and a facility checklist were used to collect the data. Data collected were analysed using frequency counts and percentages. The study revealed in this analysis that only treadmills (66.7%, bicycle ergometers (66.7%, dumbbells (84.3% and weight racks (57.0% met the benchmark minimum in more than 50% of the exercise therapy/fitness outfits surveyed in six states of the south-south geopolitical zone of Nigeria. Most of the equipment surveyed were functional with the highest non-functionality occurring in treadmill machines in 9.8% of the surveyed centres followed by sit-up benches (5.9% and bicycle ergometers (3.9%. In conclusion, it could be deduced from the results that there’s gross inadequacy of equipment and low level of compliance to established standard in the exercise therapy/fitness outfits evaluated in the south-south geopolitical zone of Nigeria.

Exercise Equipment Usability Assessment for a Deep Space Concept Vehicle

Science.gov (United States)

Rhodes, Brooke M.; Reynolds, David W.

2015-01-01

stationary bicycle. With the most current treadmill aboard the International Space Station (ISS), the Combined Operational Load-Bearing External Resistance Treadmill (COLBERT), being located in an International Standard Payload Rack (ISPR), the bottom of the conceptual treadmill features a height of 38in. Making the treadmill flush with the floor would be impossible in this rack configuration, as the distance from the outer wall of the spacecraft to the bottom floor would be too shallow. From preliminary sizing, the 38in required for the bottom of the treadmill combined with a 78in operational envelope for a 95th percentile may not be accommodated in the exercise area in a vertical orientation. Figure 2 demonstrates the volume required (in maroon) for an ISPR-bound treadmill in the concept demonstrator. Early indications as seen in this figure indicate that the crew members would contact the ceiling in such an arrangement. An assessment will be conducted to evaluate various orientations of exercise equipment in the concept demonstrator. Orientations to be tested include putting the bottom of the treadmill on the wall, having the treadmill at an angle in the floor both horizontally and vertically, and having a shorter (non-rack bound) treadmill in a vertical orientation on the floor. This assessment will yield findings regarding sizing of the area and how well participants feel they could exercise in such an environment. Due to the restrictions of assessing a microgravity vehicle in a normal-gravity environment, simulations in MSFC's Virtual Environments Lab (VEL) may be necessary. Final deliverables will include recommendations regarding the location and size of possible exercise equipment aboard the SLS-Derived DSH.

Measurement properties of maximal cardiopulmonary exercise tests protocols in persons after stroke: A systematic review.

Science.gov (United States)

Wittink, Harriet; Verschuren, Olaf; Terwee, Caroline; de Groot, Janke; Kwakkel, Gert; van de Port, Ingrid

2017-11-21

To systematically review and critically appraise the literature on measurement properties of cardiopulmonary exercise test protocols for measuring aerobic capacity, VO2max, in persons after stroke. PubMed, Embase and Cinahl were searched from inception up to 15 June 2016. A total of 9 studies were identified reporting on 9 different cardiopulmonary exercise test protocols. VO2max measured with cardiopulmonary exercise test and open spirometry was the construct of interest. The target population was adult persons after stroke. We included all studies that evaluated reliability, measurement error, criterion validity, content validity, hypothesis testing and/or responsiveness of cardiopulmonary exercise test protocols. Two researchers independently screened the literature, assessed methodological quality using the COnsensus-based Standards for the selection of health Measurement INstruments checklist and extracted data on measurement properties of cardiopulmonary exercise test protocols. Most studies reported on only one measurement property. Best-evidence synthesis was derived taking into account the methodological quality of the studies, the results and the consistency of the results. No judgement could be made on which protocol is "best" for measuring VO2max in persons after stroke due to lack of high-quality studies on the measurement properties of the cardiopulmonary exercise test.

Two Pilot Studies of the Effect of Bicycling on Balance and Leg Strength among Older Adults

OpenAIRE

Rissel, Chris; Passmore, Erin; Mason, Chloe; Merom, Dafna

2013-01-01

Objectives. Study 1 examines whether age-related declines in balance are moderated by bicycling. Study 2 tests whether regular cycling can increase leg strength and improve balance. Methods. Study 1: a cross-sectional survey of 43 adults aged 44–79 was conducted. Leg strength was measured, and Balance was measured using the choice stepping reaction time (CSRT) test (decision time and response time), leg strength and timed single leg standing. Study 2: 18 older adults aged 49–72 were recruited...

Ergonomic Analysis of UI’s BicyclesUsing Posture Evaluation Index (PEI Method in Virtual Environment

Directory of Open Access Journals (Sweden)

Erlinda Muslim

2010-10-01

Full Text Available This research was conducted to study ergonomic aspect from University of Indonesia bicycle in virtual environment. Software Jack 6.0 was used to analyze it. PEI was used as approach that integrated the results of three methods: Lower Back Analysis, Ovako Working Posture Analysis, and Rapid Upper Limb Assessment. The research objective is to evaluate existing design of University of Indonesia bicycle and to determine the most ergonomic redesign which concern with handlebar height and saddle height modification. The result showed that the most ergonomic design of University of Indonesia bicycle is the one with the highest handlebar height (22 cm and the lowest saddle height (11 cm.

Severe bicycling injury risk factors in children and adolescents: a case-control study.

Science.gov (United States)

Hagel, Brent E; Romanow, Nicole T R; Enns, Nancy; Williamson, Jacqueline; Rowe, Brian H

2015-05-01

Bicycling is the most common cause of sports and recreation injury in children and adolescents; yet, there is limited evidence on the factors associated with severe bicycling injuries in youth. Case-control study of injured bicyclists less than 18 years old seen in seven emergency departments (EDs) from May 2008 to October 2010. Cases were bicyclists hospitalized after their ED visit (severe injury). Controls were bicyclists seen and discharged from the ED (non-severe injury). Personal, environmental, and crash characteristics were collected by interview. Injury data were collected from medical charts. Crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) from logistic regression were used to estimate the odds of hospitalization associated with risk factors. Multiple imputation techniques were employed to address missing data. There were 1470 participants including 119 cases. Those ages 13-17 had the highest proportion (23%) of severe injuries resulting from motor vehicle [MV] collision. In models including age, sex and MV collision, being male (OR: 2.02; 95% CI: 1.21-3.38), not wearing a helmet (OR: 2.18; 95% CI: 1.43-3.31) and MV collision (OR: 3.91; 95% CI: 2.26-6.78) were significant risk factors for severe injury. Riding on a paved surface (OR: 0.63; 95% CI: 0.41-0.97) and utilitarian (school, work) bicycling (OR: 0.44; 95% CI: 0.2-0.94) decreased injury risk. Results were similar, apart from utilitarian bicycling (OR: 0.49; 95% CI: 0.22-1.06), after imputation for missing data. Bicycle-MV collisions increase severe injury risk in youth, and adolescents are often injured in these events. This suggests separating bicyclists from MVs or traffic calming strategies could improve safety. Copyright © 2015 Elsevier Ltd. All rights reserved.

Synthesis of novel N1-substituted bicyclic pyrazole amino acids and evaluation of their interaction with glutamate receptors

DEFF Research Database (Denmark)

Conti, Paola; Grazioso, Giovanni; di Ventimiglia, Samuele Joppolo

2005-01-01

N1-substituted bicyclic pyrazole amino acids (S)-9a-9c and (R)-9a-9c, which are conformationally constrained analogues of glutamic acid, were prepared via a strategy based on a 1,3-dipolar cycloaddition. The new amino acids were tested for activity at ionotropic and metabotropic glutamate receptors...

Exploring the Chemistry of Bicyclic Isoxazolidines for the Multicomponent Synthesis of Glycomimetic Building Blocks.

Science.gov (United States)

Hoogenboom, Jorin; Lutz, Martin; Zuilhof, Han; Wennekes, Tom

2016-10-07

Starting from a chiral furanone, the nitrone-olefin [3 + 2] cycloaddition can be used to obtain bicyclic isoxazolidines for which we report a set of reactions to selectively modify each functional position. These synthetically versatile bicyclic isoxazolidines allowed us to obtain complex glycomimetic building blocks, like iminosugars, via multicomponent chemistry. For example, a library of 20 pipecolic acid derivatives, a recurring motif in various prescription drugs, could be obtained via a one-pot Staudinger/aza-Wittig/Ugi three-component reaction of a bicyclic isoxazolidine-derived azido-hemiacetal. Notably, specific pipecolic acids in this library were obtained via hydrolysis of an unique tricyclic imidate side product of the Ugi reaction. The azido-hemiacetal was also converted into an aza-C-glycoside iminosugar via an unprecendented one-pot Staudinger/aza-Wittig/Mannich reaction.

Exercise-induced hypertension, cardiovascular events, and mortality in patients undergoing exercise stress testing: a systematic review and meta-analysis.

Science.gov (United States)

Schultz, Martin G; Otahal, Petr; Cleland, Verity J; Blizzard, Leigh; Marwick, Thomas H; Sharman, James E

2013-03-01

The prognostic relevance of a hypertensive response to exercise (HRE) is ill-defined in individuals undergoing exercise stress testing. The study described here was intended to provide a systematic review and meta-analysis of published literature to determine the value of exercise-related blood pressure (BP) (independent of office BP) for predicting cardiovascular (CV) events and mortality. Online databases were searched for published longitudinal studies reporting exercise-related BP and CV events and mortality rates. We identified for review 12 longitudinal studies with a total of 46,314 individuals without significant coronary artery disease, with total CV event and mortality rates recorded over a mean follow-up of 15.2±4.0 years. After adjustment for age, office BP, and CV risk factors, an HRE at moderate exercise intensity carried a 36% greater rate of CV events and mortality (95% CI, 1.02-1.83, P = 0.039) than that of subjects without an HRE. Additionally, each 10mm Hg increase in systolic BP during exercise at moderate intensity was accompanied by a 4% increase in CV events and mortality, independent of office BP, age, or CV risk factors (95% CI, 1.01-1.07, P = 0.02). Systolic BP at maximal workload was not significantly associated with the outcome of an increased rate of CV, whether analyzed as a categorical (HR=1.49, 95% CI, 0.90-2.46, P = 0.12) or a continuous (HR=1.01, 95% CI, 0.98-1.04, P = 0.53) variable. An HRE at moderate exercise intensity during exercise stress testing is an independent risk factor for CV events and mortality. This highlights the need to determine underlying pathophysiological mechanisms of exercise-induced hypertension.

Exercise capacity is associated with endothelin-1 release during emotional excitement in coronary artery disease patients.

Science.gov (United States)

Tulppo, Mikko P; Piira, Olli-Pekka; Hautala, Arto J; Kiviniemi, Antti M; Miettinen, Johanna A; Huikuri, Heikki V

2014-08-01

Endothelin-1 (ET-1), a potent vasoconstrictor, IL-6, and catecholamines are increased and heart rate variability [SD of normal to normal R-R intervals (SDNN)] decreased during emotional excitement, but individual responses vary. We tested the hypothesis that exercise capacity is associated with physiological responses caused by real-life emotional excitement. We measured the plasma levels of ET-1, IL-6, catecholamines, heart rate, and SDNN in enthusiastic male ice hockey spectators (n = 51; age, 59 ± 9 years) with stable coronary artery disease (CAD) at baseline and during the Finnish National Ice Hockey League's final play-off matches. Maximal exercise capacity (METs) by bicycle exercise test and left ventricular ejection fraction (LVEF) were measured on a separate day. ET-1 response from baseline to emotional excitement correlated with maximal METs (r = -0.30; P = 0.040). In a linear stepwise regression analysis age, body mass index (BMI), METs, LVEF, basal ET-1, and subjective experience of excitement were entered the model as independent variables to explain ET-1 response. This model explained 27% of ET-1 response (P = 0.003). Maximal METs were most strongly correlated with ET-1 response (β = -0.45; partial correlation r = -0.43; P = 0.002), followed by BMI (β = -0.31; partial correlation r = -0.31; P = 0.033) and LVEF (β = -0.30; partial correlation r = -0.33; P = 0.023). Exercise capacity may protect against further cardiovascular events in CAD patients, because it is associated with reduced ET-1 release during emotional excitement. Copyright © 2014 the American Physiological Society.

Device and method to determine perineal artery occlusion during road bicycling.

Science.gov (United States)

Parthiban, Sujeeth; Hotaling, James M; Ohlander, Samuel J; Baftiri, Amit P; Freels, Sally; Niederberger, Craig S

2014-01-01

Greater than 60 million American men who ride bicycles are at risk of developing erectile dysfunction. One possible reason is occlusion of the perineal arteries. Researchers relied on indirect methods and stationary models to study this problem. We developed a novel system to quantify occlusion among bicycle riders during a road bike ride. Our verification and validation activities show that this system can be safely used on human subjects to measure perineal artery occlusion. The method described in this paper provides a valuable tool to the researchers to study or to develop new solutions that alleviate this problem. The outcomes of these efforts will help millions of cyclists worldwide.

Efficacy of lung ventilation scintigram and exercise pulmonary hemodynamic measurement to evaluate operability for pulmonary resection

International Nuclear Information System (INIS)

Kaneda, Masanori; Hayashi, Takashi; Hiraiwa, Takane; Sakai, Takashi; Namikawa, Shoji; Kusakawa, Minoru.

1989-01-01

Preoperative evaluation of patients with lung cancer should include data concerning both resectability and operability. Operability addresses the question how much pulmonary tissue can be safely removed. The purpose of this study is to demonstrate an efficacy of the lung ventilation scintigram and measurement of exercise change in pulmonary hemodynamic parameters by detecting respiratory and circulatory reserve of pulmonary function. Predicted postoperative forced vital capacity (FVC) were calculated from the data of lung scintigram and preoperative spirometry by means of subsegmental formula. Accuracy of prediction was confirmed by spirometry 6 months after the operation. Correlation coefficient between predicted value and actually measured one was R=0.95, and simple regression formula was y=0.98x-10.4. It was recommended that the lower limit should be setted at 40% by the calculated postoperative %FVC. Exercise test were performed by means of bicycle ergometer with the measurement of pulmonary arterial pressure and cardiac output. Pulmonary arterial resistance index (PARI) were also calculated. In younger group rise of pulmonary arterial pressure during exercise was gentle, and PARI was settled between 150 to 200 in high output state. But in older group rise of pulmonary aerial pressure was steep and PARI was over 200 in some cases, just like the case of COLD. It should be recommended to set the upper limit of PARI at 400 in maximum exercise. (author)

Relation between exercise-induced ventricular arrhythmias and myocardial perfusion abnormalities in patients with intermediate pretest probability of coronary artery disease

International Nuclear Information System (INIS)

Elhendy, A.; Sozzi, F.B.; Van Domburg, R.T.; Bax, J.J.; Roelandt, J.R.T.C.

2000-01-01

We studied 302 patients (mean age 54±9 years, 152 men and 150 women) with intermediate pretest probability of CAD (range=0.25- 0.80, mean=0.43±0.20) by upright bicycle exercise stress test in conjunction with technetium-99m single-photon emission tomography (SPET) imaging. Exercise-induced VAs (frequent or complex premature ventricular contractions or ventricular tachycardia) occurred in 65 patients (22%). No significant difference was found between patients with and patient without VAs regarding the pretest probability of CAD (0.45±0.21 vs 0.43±0.20). Patients with exercise-induced VAs had a higher prevalence of perfusion abnormalities (52% vs 26%, P=0.002) and ischaemic electrocardiographic changes (31% vs 16%, P<0.05) compared to patients without VAs. A higher prevalence of perfusion abnormalities in patients with VAs was observed in both men (67% vs 35%, P<0.01) and women (38% vs 16%, P<0.05). However, the positive predictive value of exercise-induced VAs for the presence of myocardial perfusion abnormalities was higher in men than in women (67% vs 38%, P<0.05). The presence of abnormal myocardial perfusion was the only independent predictor of exercise-induced VAs (OR 2.2; 95% CI, 1.2-4.2) by multivariate analysis of clinical and stress test variables. It is concluded that in patients with intermediate pretest probability of CAD, exercise-induced VAs are predictive of a higher prevalence of myocardial perfusion abnormalities in both men and women. However, the positive predictive value of exercise-induced VAs for perfusion abnormalities is higher in men. Because of the underestimation of ischaemia by electrocardiographic changes, exercise-induced VAs should be interpreted as a marker of a higher probability of CAD. (orig./MG) (orig.)

Physical Exercise Keeps the Brain Connected: Biking Increases White Matter Integrity in Patients With Schizophrenia and Healthy Controls.

Science.gov (United States)

Svatkova, Alena; Mandl, René C W; Scheewe, Thomas W; Cahn, Wiepke; Kahn, René S; Hulshoff Pol, Hilleke E

2015-07-01

It has been shown that learning a new skill leads to structural changes in the brain. However, it is unclear whether it is the acquisition or continuous practicing of the skill that causes this effect and whether brain connectivity of patients with schizophrenia can benefit from such practice. We examined the effect of 6 months exercise on a stationary bicycle on the brain in patients with schizophrenia and healthy controls. Biking is an endemic skill in the Netherlands and thus offers an ideal situation to disentangle the effects of learning vs practice. The 33 participating patients with schizophrenia and 48 healthy individuals were assigned to either one of two conditions, ie, physical exercise or life-as-usual, balanced for diagnosis. Diffusion tensor imaging brain scans were made prior to and after intervention. We demonstrate that irrespective of diagnosis regular physical exercise of an overlearned skill, such as bicycling, significantly increases the integrity, especially of motor functioning related, white matter fiber tracts whereas life-as-usual leads to a decrease in fiber integrity. Our findings imply that exercise of an overlearned physical skill improves brain connectivity in patients and healthy individuals. This has important implications for understanding the effect of fitness programs on the brain in both healthy subjects and patients with schizophrenia. Moreover, the outcome may even apply to the nonphysical realm. © The Author 2015. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Bicycle Facilities That Address Safety, Crime, and Economic Development: Perceptions from Morelia, Mexico

Directory of Open Access Journals (Sweden)

Inés Alveano-Aguerrebere

2017-12-01

Full Text Available México is a developing nation and, in the city of Morelia, the concept of the bicyclist as a road user appeared only recently in the Municipal Traffic Regulations. Perhaps the right bicycle infrastructure could address safety, crime, and economic development. To identify the best infrastructure, six groups in Morelia ranked and commented on pictures of bicycle environments that exist in bicycle-friendly nations. Perceptions about bike paths, but only those with impossible-to-be-driven-over solid barriers, were associated with safety from crashes, lowering crime, and contributing to economic development. Shared use paths were associated with lowering the probability of car/bike crashes but lacked the potential to deter crime and foster the local economy. Joint bus and bike lanes were associated with lower safety because of the unwillingness by Mexican bus drivers to be courteous to bicyclists. Gender differences about crash risk biking in the road with the cars (6 best/0 worst scenario were statistically significant (1.4 for male versus 0.69 for female; p < 0.001. For crashes, crime, and economic development, perceptions about bicycle infrastructure were different in this developing nation perhaps because policy, institutional context, and policing (ticketing for unlawful parking are not the same as in a developed nation. Countries such as Mexico should consider building cycle tracks with solid barriers to address safety, crime, and economic development.

Bicycle Facilities That Address Safety, Crime, and Economic Development: Perceptions from Morelia, Mexico

Science.gov (United States)

Alveano-Aguerrebere, Inés; Farvid, Maryam; Lusk, Anne

2017-01-01

México is a developing nation and, in the city of Morelia, the concept of the bicyclist as a road user appeared only recently in the Municipal Traffic Regulations. Perhaps the right bicycle infrastructure could address safety, crime, and economic development. To identify the best infrastructure, six groups in Morelia ranked and commented on pictures of bicycle environments that exist in bicycle-friendly nations. Perceptions about bike paths, but only those with impossible-to-be-driven-over solid barriers, were associated with safety from crashes, lowering crime, and contributing to economic development. Shared use paths were associated with lowering the probability of car/bike crashes but lacked the potential to deter crime and foster the local economy. Joint bus and bike lanes were associated with lower safety because of the unwillingness by Mexican bus drivers to be courteous to bicyclists. Gender differences about crash risk biking in the road with the cars (6 best/0 worst scenario) were statistically significant (1.4 for male versus 0.69 for female; p < 0.001). For crashes, crime, and economic development, perceptions about bicycle infrastructure were different in this developing nation perhaps because policy, institutional context, and policing (ticketing for unlawful parking) are not the same as in a developed nation. Countries such as Mexico should consider building cycle tracks with solid barriers to address safety, crime, and economic development. PMID:29271873

Bicycle Facilities That Address Safety, Crime, and Economic Development: Perceptions from Morelia, Mexico.

Science.gov (United States)

Alveano-Aguerrebere, Inés; Javier Ayvar-Campos, Francisco; Farvid, Maryam; Lusk, Anne

2017-12-22

México is a developing nation and, in the city of Morelia, the concept of the bicyclist as a road user appeared only recently in the Municipal Traffic Regulations. Perhaps the right bicycle infrastructure could address safety, crime, and economic development. To identify the best infrastructure, six groups in Morelia ranked and commented on pictures of bicycle environments that exist in bicycle-friendly nations. Perceptions about bike paths, but only those with impossible-to-be-driven-over solid barriers, were associated with safety from crashes, lowering crime, and contributing to economic development. Shared use paths were associated with lowering the probability of car/bike crashes but lacked the potential to deter crime and foster the local economy. Joint bus and bike lanes were associated with lower safety because of the unwillingness by Mexican bus drivers to be courteous to bicyclists. Gender differences about crash risk biking in the road with the cars (6 best/0 worst scenario) were statistically significant (1.4 for male versus 0.69 for female; p < 0.001). For crashes, crime, and economic development, perceptions about bicycle infrastructure were different in this developing nation perhaps because policy, institutional context, and policing (ticketing for unlawful parking) are not the same as in a developed nation. Countries such as Mexico should consider building cycle tracks with solid barriers to address safety, crime, and economic development.

The 1-Minute Sit-to-Stand Test in Adults With Cystic Fibrosis: Correlations With Cardiopulmonary Exercise Test, 6-Minute Walk Test, and Quadriceps Strength.

Science.gov (United States)

Gruet, Mathieu; Peyré-Tartaruga, Leonardo Alexandre; Mely, Laurent; Vallier, Jean-Marc

2016-12-01

Exercise testing is part of the regular assessment of patients with cystic fibrosis (CF). We aimed to evaluate (1) the convergent validity of the 1-min sit-to-stand (STS) test in CF by investigating its relationships with peak oxygen uptake (peak V̇ O 2 ), quadriceps strength, and quality of life and (2) to compare these associations with those of the 6-min walk test (6MWT). Twenty-five adults with CF (FEV 1 = 59 ± 24%) performed the STS test, the 6MWT, quadriceps strength assessment, and cardiopulmonary exercise test (CPET). Physical activity level, quality of life, and self-esteem were assessed by questionnaires. STS repetitions, 6-min walk distance, quadriceps strength, and peak V̇ O 2 were, respectively, 71 ± 12, 90 ± 10, 93 ± 29, and 62 ± 16% of predicted. The STS test had moderate associations with peak V̇ O 2 (r = 0.56, P = .004), quadriceps strength (r = 0.52, P = .008), and some questionnaire items (eg, perceived physical strength, r = 0.67, P test was strongly associated with oxygen desaturation during CPET (r = 0.80, P test as compared with CPET (P test cannot be used as a replacement for CPET to accurately assess peak exercise capacity in CF. The STS test may have utility in detecting patients with CF who may exhibit a high level of oxygen desaturation during heavy exercise. Further studies should identify the factors contributing to STS performance to confirm the potential interest of STS repetitions × body weight outcome as a useful submaximal exercise parameter in CF. Copyright © 2016 by Daedalus Enterprises.

Using Smartphones to Collect Bicycle Travel Data in Texas

Science.gov (United States)

2012-08-08

Researchers believed that if smartphones could prove to be an effective tool for collecting bicycle travel data, the information could be used for aiding decision making as to what types of facilities users prefer and guiding decisions about future f...

preparation of bicyclic lactones using lewis acids catalyzed ene

African Journals Online (AJOL)

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The synthesis of the cis-fused bicyclic lactones relies extensively on the Lewis acid ... having an allylic hydrogen (an"ene") and a compound containing an electron .... observed that the lithium enolate obtained from 3-methyl-2(5H)- furanone ...

Clinical Effects of a Dietary Antioxidant Silicate Supplement, Microhydrin((R)), on Cardiovascular Responses to Exercise.

Science.gov (United States)

Purdy Lloyd, Kimberly L.; Wasmund, Wendy; Smith, Leonard; Raven, Peter B.

2001-01-01

Amorphous silicate minerals, often described as rock flour, were once common in natural water sources and abundant in glacial stream waters. Not only do the silica mineral particles bond water and other elements for transport; they also can be adsorbed with reduced hydrogen, which releases electrons, providing antioxidant or reducing potential to surrounding fluids. The purpose of this investigation was to examine the cardiovascular responses during exercise after consumption of a dietary silicate mineral antioxidant supplement, Microhydrin((R)) (Royal BodyCare, Inc., Irving, TX). A clinical trial incorporating a double-blind, placebo-controlled, crossover experimental design was employed. Subjects received either active agent or placebo, four capsules per day, for 7 days before the trial. The trial evaluated six exercise bicycle-trained subjects performing a 40-km bicycling time trial. Ratings of perceived exertion and measurements of oxygen uptake, heart rate, performance workload, and preexercise and postexercise blood lactate concentrations were obtained. Although there were no differences (P >/=.05) in work performed, heart rate, oxygen uptake, and ratings of perceived exertion during the time trial, the postexercise blood lactate concentrations were significantly lower (P

Reliability of Strength Testing using the Advanced Resistive Exercise Device and Free Weights

Science.gov (United States)

English, Kirk L.; Loehr, James A.; Laughlin, Mitzi A.; Lee, Stuart M. C.; Hagan, R. Donald

2008-01-01

The Advanced Resistive Exercise Device (ARED) was developed for use on the International Space Station as a countermeasure against muscle atrophy and decreased strength. This investigation examined the reliability of one-repetition maximum (1RM) strength testing using ARED and traditional free weight (FW) exercise. Methods: Six males (180.8 +/- 4.3 cm, 83.6 +/- 6.4 kg, 36 +/- 8 y, mean +/- SD) who had not engaged in resistive exercise for at least six months volunteered to participate in this project. Subjects completed four 1RM testing sessions each for FW and ARED (eight total sessions) using a balanced, randomized, crossover design. All testing using one device was completed before progressing to the other. During each session, 1RM was measured for the squat, heel raise, and deadlift exercises. Generalizability (G) and intraclass correlation coefficients (ICC) were calculated for each exercise on each device and were used to predict the number of sessions needed to obtain a reliable 1RM measurement (G . 0.90). Interclass reliability coefficients and Pearson's correlation coefficients (R) also were calculated for the highest 1RM value (1RM9sub peak)) obtained for each exercise on each device to quantify 1RM relationships between devices.

Skeletal muscle phosphatidylcholine and phosphatidylethanolamine respond to exercise and influence insulin sensitivity in men.

Science.gov (United States)

Lee, Sindre; Norheim, Frode; Gulseth, Hanne L; Langleite, Torgrim M; Aker, Andreas; Gundersen, Thomas E; Holen, Torgeir; Birkeland, Kåre I; Drevon, Christian A

2018-04-25

Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) composition in skeletal muscle have been linked to insulin sensitivity. We evaluated the relationships between skeletal muscle PC:PE, physical exercise and insulin sensitivity. We performed lipidomics and measured PC and PE in m. vastus lateralis biopsies obtained from 13 normoglycemic normal weight men and 13 dysglycemic overweight men at rest, immediately after 45 min of cycling at 70% maximum oxygen uptake, and 2 h post-exercise, before as well as after 12 weeks of combined endurance- and strength-exercise intervention. Insulin sensitivity was monitored by euglycemic-hyperinsulinemic clamp. RNA-sequencing was performed on biopsies, and mitochondria and lipid droplets were quantified on electron microscopic images. Exercise intervention for 12 w enhanced insulin sensitivity by 33%, skeletal muscle levels of PC by 21%, PE by 42%, and reduced PC:PE by 16%. One bicycle session reduced PC:PE by 5%. PC:PE correlated negatively with insulin sensitivity (β = -1.6, P insulin sensitivity.

Flow for Exercise Adherence: Testing an Intrinsic Model of Health Behavior

Science.gov (United States)

Petosa, R. Lingyak; Holtz, Brian

2013-01-01

Background: Health behavior theory generally does not include intrinsic motivation as a determinate of health practices. Purpose: The purpose of this study was to test the flow theory of exercise adherence. Flow theory posits that exercise can be intrinsically rewarding if the experiences of self/time transcendence and control/mastery are achieved…

[Clinical exercise testing and the Fick equation: strategic thinking for optimizing diagnosis].

Science.gov (United States)

Perrault, H; Richard, R

2012-04-01

This article examines the expected exercise-induced changes in the components of the oxygen transport system as described by the Fick equation with a view to enable a critical analysis of a standard incremental exercise test to identify normal and abnormal patterns of responses and generate hypotheses as to potential physiological and/or pathophysiological causes. The text reviews basic physiological principals and provides useful reminders of standard equations that serve to integrate circulatory, respiratory and skeletal muscle functions. More specifically, the article provides a conceptual and quantitative framework linking the exercise-induced increase in whole body oxygen uptake to central circulatory and peripheral circulatory factors with the view to establish the normalcy of response. Thus, the article reviews the exercise response to cardiac output determinants and provides qualitative and quantitative perspective bases for making assumptions on the peripheral circulatory factors and oxygen use. Finally, the article demonstrates the usefulness of exercise testing as an effective integrative physiological approach to develop clinical reasoning or verify pathophysiological outcomes. Copyright © 2012 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Automatic Stabilization of a Riderless Bicycle using the Active Disturbance Rejection Control Approach

Directory of Open Access Journals (Sweden)

Mauro Baquero-Suárez

2017-12-01

Full Text Available This work proposes an ADRC (Active Disturbance Rejection Control strategy by disturbance extended observers to stabilize a moving riderless bicycle with a variant forward speed. Although the bicycle has an unstable and non-linear dynamics when in its upright position, which can be modeled as a LPV (Linear-Parameter-Varying system that depends on the forward speed, a simplified time-invariant and lumped-parameter model, with an nominal constant forward speed is used in the controller design. ADRC scheme groups discrepancies between the simplified model and the plant, with external disturbances into an equivalent additive unified disturbance signal at input, which is estimated via the observer and rejected through a linear control law. The effectiveness of this strategy is validated by a co-simulation between ADAMS and MATLAB, which exhibits a high performance and robustness in a virtual dynamic model of the bicycle, submitted to severe external disturbances and parameter variations.

Effect of exercise on circulating atrial natriuretic peptide and left ventricular ejection fraction in healthy persons and patients with coronary artery disease

International Nuclear Information System (INIS)

Nakamura, Tetsuya; Ichikawa, Shuichi; Sakamaki, Tetsuo; Suzuki, Tadashi; Iizuka, Toshio; Yagi, Atsuko; Kurashina, Toshiaki; Kumakura, Hisao; Murata, Kazuhiko

1988-01-01

Radionuclide angiographic measurements of left ventricular ejection fraction were performed at rest and during exercise in 10 normal persons and 11 patients with coronary artery disease. Exercise was continued on a supine bicycle exercise table up to a symptom-limited maximum. Plasma levels of atrial natriuretic peptide (ANP) were also determined at rest and during exercise. Ejection fraction in the normal volunteers was 59±3% (mean±SEM) at rest and increased significantly (p<0.01) to 69±3% during exercise. Ejection fraction in the patients was 47±5% at rest and did not change significantly during exercise (51±7%). Plasma ANP in the normals rose significantly (p<0.01) from 62±16 pg/ml at rest to 454±94 pg/ml during exercise. Plasma ANP in the patients also rose significantly (p<0.01) from 231±102 pg/ml to 794±170 pg/ml. The response of plasma ANP to exercise was enhanced significantly (p<0.05) in the patients as compared with the normals in relation to ejection fraction by analysis of covariance. In both the normals and the patients, plasma ANP was inversely and significantly correlated with ejection fraction during exercise (r=0.46, p<0.05, n=21), however, not at rest. Because it has been reported that plasma ANP is correlated positively with pulmonary artery wedge pressure, the estimation of plasma ANP during an exercise stress test might be used for the evaluation of cardiac reserve in coronary artery disease. (author)

Predicting bicycle helmet stage-of-change among middle school, high school, and college cyclists from demographic, cognitive, and motivational variables.

Science.gov (United States)

Weiss, Jeffrey; Okun, Morris; Quay, Nancy

2004-09-01

To apply Prochaska's Transtheoretical model of behavior change to bicycle helmet use among middle school, high school, and college students. A battery of questionnaires was administered to cyclists in the seventh and ninth grades and to college students in Phoenix, Arizona (N=797). The battery included: (1) a question to determine respondent's stage of behavior change in Prochaska's Transtheoretical model; (2) items assessing the perceived pros and cons of helmet use; (3) a bicycle safety knowledge test; and (4) demographic information. Forty-three percent of the students were in "Precontemplation," 17% were in either "Contemplation" or "Preparation," 16% were in either "Action" or "Maintenance," and 24% were in the "Relapse" stage of change. Grade, Sex, Knowledge, Pros, and Cons, and the Grade by sex and the Grade by knowledge interactions were significant predictors of helmet use stages. Compared with students in Precontemplation, students in the Contemplation stage were disproportionately younger and had higher Pro scores, lower Con scores, and more knowledge (except in the ninth grade). The Transtheoretical model of behavior change is a viable theoretical framework for designing interventions aimed at increasing bicycle helmet use in children and adolescents.

A study of exercise ECT

International Nuclear Information System (INIS)

Nohara, Ryuji; Suzuki, Yukisono; Tamaki, Shunichi; Kadota, Kazunori; Kambara, Hirofumi; Kawai, Chuichi; Tamaki, Nagara; Toritsuka, Kanji

1984-01-01

Twenty-five patients with angina pectoris, 18 patients with post-myocardial infarction angina and 2 normal patients (mean age of 57 years, male/ female=40/5) were examined by exercise thallium-201 emission computed tomography (ECT). The results were compared to those of planar scintigraphy. A large-field-of-view gamma camera with a high resolution pallarel-hole collimator supported by gantry was rotated 180 0 around the long axis of the patient. Thirty-two different views every 5.8 0 with sampling time of 20 seconds each were obtained. Total acquisition time was 11 minutes. Data collection started from the left posterior oblique view and ended at the right anterior oblique view. Exercise was performed by graded bicycle ergometer. Post exercise ECT was compared to that of reperfusion imaging 2-3 hours after exercise. Sensitivity and specificity to detect involved coronary arteries by identifying myocardial perfusion defect were 96 and 86% ; 84 and 92% ; 81 and 100% for the right coronary artery (RCA), the left anterior descending artery (LAD) and the left circumflex artery (LCX), respectively. These data surpassed to those of planar scintigraphy (83 and 86% ; 66 and 85% ; 38 and 100% for RCA, LAD-and LCX, respectively). Especially in 3 vessel discase, ECT revealed better sensitivity (100%, 86%, 79% for RCA, LAD and LCX, respectively) than that to planar imaging (86%, 57%, 29% respectively). For 1, 2 and 0 vessel discase sensitivity and specificity of both techniques were comparable, though specificity of ECT tended to be a little better than planar's one. In conclusion, exercise ECT was very useful for detection of coronary lesions, especially in 3 vessel disease. (author)

Exercise testing in children with Wolff-Parkinson-White syndrome: what is its value?

Science.gov (United States)

Dalili, M; Vahidshahi, K; Aarabi-Moghaddam, M Y; Rao, J Y; Brugada, P

2014-10-01

This study was conducted to evaluate the accuracy of exercise testing for predicting accessory pathway characteristics in children with Wolff-Parkinson-White (WPW) syndrome. The study enrolled 37 children with WPW syndrome and candidates for invasive electrophysiologic study (EPS). Exercise testing was performed for all the study participants before the invasive study. Data from the invasive EPS were compared with findings from the exercise testing. The sudden disappearance of the delta (Δ) wave was seen in 10 cases (27 %). No significant correlation was found between the Δ wave disappearance and the antegrade effective refractory period of the accessory pathway (AERP-AP) or the shortest pre-excited RR interval (SPERRI). The sensitivity, specificity, and positive and negative predictive values of Δ wave disappearance, based on AERP-AP as gold standard, were respectively 29.4, 80, 71.4, and 40 %. The corresponding values with SPERRI as the gold standard were respectively 23.8, 71.4, 71.4 and 23.8 %. Exercise testing has a medium to low rate of accuracy in detecting low-risk WPW syndrome patients in the pediatric age group.

Investigation of the role of bicyclic peroxy radicals in the oxidation mechanism of toluene.

Science.gov (United States)

Birdsall, Adam W; Andreoni, John F; Elrod, Matthew J

2010-10-07

The products of the primary OH-initiated oxidation of toluene were investigated using the turbulent flow chemical ionization mass spectrometry technique under different oxygen, NO, and initial OH radical concentrations as well as a range of total pressures. The bicyclic peroxy radical intermediate, a key proposed intermediate species in the Master Chemical Mechanism (MCM) for the atmospheric oxidation of toluene, was detected for the first time. The toluene oxidation mechanism was shown to have a strong oxygen concentration dependence, presumably due to the central role of the bicyclic peroxy radical in determining the stable product distribution at atmospheric oxygen concentrations. The results also suggest a potential role for bicyclic peroxy radical + HO(2) reactions at high HO(2)/NO ratios. These reactions are postulated to be a source of the inconsistencies between environmental chamber results and predictions from the MCM.

Unilateral Arm Crank Exercise Test for Assessing Cardiorespiratory Fitness in Individuals with Hemiparetic Stroke

DEFF Research Database (Denmark)

Oyake, Kazuaki; Yamaguchi, Tomofumi; Oda, Chihiro

2017-01-01

Cardiorespiratory fitness assessment with leg cycle exercise testing may be influenced by motor impairments in the paretic lower extremity. Hence, this study examined the usefulness of a unilateral arm crank exercise test to assess cardiorespiratory fitness in individuals with stroke, including s...

Assessing and Mapping of Road Surface Roughness based on GPS and Accelerometer Sensors on Bicycle-Mounted Smartphones

Science.gov (United States)

Shen, Jie; Wan, Mi; Shi, Jiafeng

2018-01-01

The surface roughness of roads is an essential road characteristic. Due to the employed carrying platforms (which are often cars), existing measuring methods can only be used for motorable roads. Until now, there has been no effective method for measuring the surface roughness of un-motorable roads, such as pedestrian and bicycle lanes. This hinders many applications related to pedestrians, cyclists and wheelchair users. In recognizing these research gaps, this paper proposes a method for measuring the surface roughness of pedestrian and bicycle lanes based on Global Positioning System (GPS) and accelerometer sensors on bicycle-mounted smartphones. We focus on the International Roughness Index (IRI), as it is the most widely used index for measuring road surface roughness. Specifically, we analyzed a computing model of road surface roughness, derived its parameters with GPS and accelerometers on bicycle-mounted smartphones, and proposed an algorithm to recognize potholes/humps on roads. As a proof of concept, we implemented the proposed method in a mobile application. Three experiments were designed to evaluate the proposed method. The results of the experiments show that the IRI values measured by the proposed method were strongly and positively correlated with those measured by professional instruments. Meanwhile, the proposed algorithm was able to recognize the potholes/humps that the bicycle passed. The proposed method is useful for measuring the surface roughness of roads that are not accessible for professional instruments, such as pedestrian and cycle lanes. This work enables us to further study the feasibility of crowdsourcing road surface roughness with bicycle-mounted smartphones. PMID:29562731

The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material

OpenAIRE

BRENT TAYLOR, NICHOLAS

2016-01-01

[EN] ABSTRACT Nicholas Brent Taylor: The Feasibility of Wood and its Derivatives as a Bicycle Frame Building Material The bicycle is often considered as one of the most important inventions of all time. In addition, it is the most efficient form of human transport in the world. It is non pollutant, uses no fuel other than human power and its carbon footprint is neutralised in a short time. Today, faced with the threat of global warming brought about by fossil fuels, countries such as De...

Similar carbohydrate but enhanced lactate utilization during exercise after 9 wk of acclimatization to 5,620 m

DEFF Research Database (Denmark)

Van Hall, Gerrit; Calbet, J A L; Sondergaard, H

2002-01-01

We hypothesized that reliance on lactate as a means of energy distribution is higher after a prolonged period of acclimatization (9 wk) than it is at sea level due to a higher lactate Ra and disposal from active skeletal muscle. To evaluate this hypothesis, six Danish lowlanders (25 +/- 2 yr) were...... studied at rest and during 20 min of bicycle exercise at 146 W at sea level (SL) and after 9 wk of acclimatization to 5,260 m (Alt). Whole body glucose Ra was similar at SL and Alt at rest and during exercise. Lactate Ra was also similar for the two conditions at rest; however, during exercise, lactate Ra...... was substantially lower at SL (65 micro mol. min(-1). kg body wt(-1)) than it was at Alt (150 micro mol. min(-1). kg body wt(-1)) at the same exercise intensity. During exercise, net lactate release was approximately 6-fold at Alt compared with SL, and related to this, tracer-calculated leg lactate uptake...

An Exercise for Illustrating the Logic of Hypothesis Testing

Science.gov (United States)

Lawton, Leigh

2009-01-01

Hypothesis testing is one of the more difficult concepts for students to master in a basic, undergraduate statistics course. Students often are puzzled as to why statisticians simply don't calculate the probability that a hypothesis is true. This article presents an exercise that forces students to lay out on their own a procedure for testing a…

Effect of suspension systems on the physiological and psychological responses to sub-maximal biking on simulated smoothand bumpy tracks.

Science.gov (United States)

Titlestad, John; Fairlie-Clarke, Tony; Whittaker, Arthur; Davie, Mark; Watt, Ian; Grant, Stanley

2006-02-01

The aim of this study was to compare the physiological and psychological responses of cyclists riding on a hard tail bicycle and on a full suspension bicycle. Twenty males participated in two series of tests. A test rig held the front axle of the bicycle steady while the rear wheel rotated against a heavy roller with bumps (or no bumps) on its surface. In the first series of tests, eight participants (age 19-27 years, body mass 65-82 kg) were tested on both the full suspension and hard tail bicycles with and without bumps fitted to the roller. The second series of test repeated the bump tests with a further six participants (age 22-31 years, body mass 74-94 kg) and also involved an investigation of familiarization effects with the final six participants (age 21-30 years, body mass 64-80 kg). Heart rate, oxygen consumption (VO(2)), rating of perceived exertion (RPE) and comfort were recorded during 10 min sub-maximal tests. Combined data for the bumps tests show that the full suspension bicycle was significantly different (P < 0.001) from the hard tail bicycle on all four measures. Oxygen consumption, heart rate and RPE were lower on average by 8.7 (s = 3.6) ml . kg(-1) . min(-1), 32.1 (s = 12.1) beats . min(-1) and 2.6 (s = 2.0) units, respectively. Comfort scores were higher (better) on average by 1.9 (s = 0.8) units. For the no bumps tests, the only statistically significant difference (P = 0.008) was in VO(2), which was lower for the hard tail bicycle by 2.2 (s = 1.7) ml . kg(-1) . min(-1). The results indicate that the full suspension bicycle provides a physiological and psychological advantage over the hard tail bicycle during simulated sub-maximal exercise on bumps.

A Pilot Test of the Additive Benefits of Physical Exercise to CBT for OCD.

Science.gov (United States)

Rector, Neil A; Richter, Margaret A; Lerman, Bethany; Regev, Rotem

2015-01-01

The majority of "responders" to first-line cognitive-behavioural therapy (CBT) and pharmacological treatments for obsessive-compulsive disorder (OCD) are left with residual symptoms that are clinically relevant and disabling. Therefore, there is pressing need for widely accessible efficacious alternative and/or adjunctive treatments for OCD. Accumulating evidence suggests that physical exercise may be one such intervention in the mood and anxiety disorders broadly, although we are aware of only two positive small-scale pilot studies that have tested its clinical benefits in OCD. This pilot study aimed to test the feasibility and preliminary efficacy of adding a structured physical exercise programme to CBT for OCD. A standard CBT group was delivered concurrently with a 12-week customized exercise programme to 11 participants. The exercise regimen was individualized for each participant based on peak heart rate measured using an incremental maximal exercise test. Reports of exercise adherence across the 12-week regimen exceeded 80%. A paired-samples t-test indicated very large treatment effects in Yale-Brown Obsessive-Compulsive Scale scores from pre- to post-treatment in CBT group cohorts led by expert CBT OCD specialists (d = 2.55) and junior CBT clinician non-OCD specialists (d = 2.12). These treatment effects are very large and exceed effects typically observed with individual and group-based CBT for OCD based on leading meta-analytic reviews, as well as previously obtained treatment effects for CBT using the same recruitment protocol without exercise. As such, this pilot work demonstrates the feasibility and significant potential clinical utility of a 12-week aerobic exercise programme delivered in conjunction with CBT for OCD.

Real-time bicycle detection at signalized intersections using thermal imaging technology

Science.gov (United States)

Collaert, Robin

2013-02-01

More and more governments and authorities around the world are promoting the use of bicycles in cities, as this is healthy for the bicyclist and improves the quality of life in general. Safety and efficiency of bicyclists has become a major focus. To achieve this, there is a need for a smarter approach towards the control of signalized intersections. Various traditional detection technologies, such as video, microwave radar and electromagnetic loops, can be used to detect vehicles at signalized intersections, but none of these can consistently separate bikes from other traffic, day and night and in various weather conditions. As bikes should get a higher priority and also require longer green time to safely cross the signalized intersection, traffic managers are looking for alternative detection systems that can make the distinction between bicycles and other vehicles near the stop bar. In this paper, the drawbacks of a video-based approach are presented, next to the benefits of a thermal-video-based approach for vehicle presence detection with separation of bicycles. Also, the specific technical challenges are highlighted in developing a system that combines thermal image capturing, image processing and output triggering to the traffic light controller in near real-time and in a single housing.

A Study for Adjustable Riding Position of the Innovation Bicycle Design

Science.gov (United States)

Huang, Yu-Che; Huang, Tai-Shen

2018-04-01

This research is about the analysis and design of the user in a wheelchair use posture can be changed. So user can through different sitting posture changes to provide different needs, so the folding design patents for the existing data collection and classification, through the analysis of advantages and disadvantages, further to find the innovative design approach. Finally through the multi linkage mechanism system, change the seat, handlebars and rear position, provide different posture context. In order to reduce the cost, this study is designed to integrate the innovation input mechanism, multi linkage system, through the construction of 10 joints and degrees of freedom of the bicycle frame. Then use 3D software to design of bicycle the size of the frame of innovation, through the three-dimensional CAD model to simulate the mechanism between movement and interference, and to evaluate the 3D The virtual prototype can meet the requirement. It will also enable CAE to analyze and determine the strength and the safety of the bicycle frame structure of ANSYS11.0 stress. Finally, we have integrated design through CAID to make a product appearance, the focus of research is mainly a study of CAD, CAE, CAID integration the production and the completion of a prototype.

Monitoring ventricular function at rest and during exercise with a nonimaging nuclear detector

International Nuclear Information System (INIS)

Wagner, H.N. Jr.; Rigo, P.; Baxter, R.H.; Alderson, P.O.; Douglass, K.H.; Housholder, D.F.

1979-01-01

A portable nonimaging device, the nuclear stethoscope, for measuring beat to beat ventricular time-activity curves in normal people and patients with heart disease, both at rest and during exercise, is being developed and evaluated. The latest device has several operting modes that facilitate left ventricular and background localization, measurement of transit times and automatic calculation and display of left ventricular ejection fraction. The correlation coefficient of left ventricular ejection fraction obtained with the device and with a camera-computer system was 0.92 in 35 subjects. During bicycle exercise the ejection fraction in 15 normal persons increased from 44 to 64% (P less than 0.001), whereas among 12 patients with heart disease it was unchanged in 5 and decreased in 7

Monitoring ventricular function at rest and during exercise with a nonimaging nuclear detector.

Science.gov (United States)

Wagner, H N; Rigo, P; Baxter, R H; Alderson, P O; Douglass, K H; Housholder, D F

1979-05-01

A portable nonimaging device, the nuclear stethoscope, for measuring beat to beat ventricular time-activity curves in normal people and patients with heart disease, both at rest and during exercise, is being developed and evaluated. The latest device has several operating modes that facilitate left ventricular and background localization, measurement of transit times and automatic calculation and display of left ventricular ejection fraction. The correlation coefficient of left ventricular ejection fraction obtained with the device and with a camera-computer system was 0.92 in 35 subjects. During bicycle exercise the ejection fraction in 15 normal persons increased from 44 to 64 percent (P less than 0.001), whereas among 12 patients with heart disease it was unchanged in 5 and decreased in 7.

The Politics of Bicycle Innovation: Comparing the American and Dutch Human-Powered Vehicle Movements, 1970s—present

NARCIS (Netherlands)

Stoffers, M.; Oldenziel, R; Trischler, H

2016-01-01

This paper deals with the history of the international Human-Powered Vehicle (HPV) movement, originally launched in the 1970s by engineers and scientists who believed that bicycle innovation could give a major impetus to a coveted western bicycle renaissance. Based on a reading of magazines and

Perceiving and Acting on Complex Affordances: How Children and Adults Bicycle across Two Lanes of Opposing Traffic

Science.gov (United States)

Grechkin, Timofey Y.; Chihak, Benjamin J.; Cremer, James F.; Kearney, Joseph K.; Plumert, Jodie M.

2013-01-01

This investigation examined how children and adults negotiate a challenging perceptual-motor problem with significant real-world implications--bicycling across two lanes of opposing traffic. Twelve- and 14-year-olds and adults rode a bicycling simulator through an immersive virtual environment. Participants crossed intersections with continuous…

Reduced peripheral arterial blood flow with preserved cardiac output during submaximal bicycle exercise in elderly heart failure

Directory of Open Access Journals (Sweden)

Leng Xiaoyan

2009-11-01

Full Text Available Abstract Background Older heart failure (HF patients exhibit exercise intolerance during activities of daily living. We hypothesized that reduced lower extremity blood flow (LBF due to reduced forward cardiac output would contribute to submaximal exercise intolerance in older HF patients. Methods and Results Twelve HF patients both with preserved and reduced left ventricular ejection fraction (LVEF (aged 68 ± 10 years without large (aorta or medium sized (iliac or femoral artery vessel atherosclerosis, and 13 age and gender matched healthy volunteers underwent a sophisticated battery of assessments including a peak exercise oxygen consumption (peak VO2, b physical function, c cardiovascular magnetic resonance (CMR submaximal exercise measures of aortic and femoral arterial blood flow, and d determination of thigh muscle area. Peak VO2 was reduced in HF subjects (14 ± 3 ml/kg/min compared to healthy elderly subjects (20 ± 6 ml/kg/min (p = 0.01. Four-meter walk speed was 1.35 ± 0.24 m/sec in healthy elderly verses 0.98 ± 0.15 m/sec in HF subjects (p p ≤ 0.03. Conclusion During CMR submaximal bike exercise in the elderly with heart failure, mechanisms other than low cardiac output are responsible for reduced lower extremity blood flow.

Street Intersection Characteristics and Their Impacts on Perceived Bicycling Safety

Science.gov (United States)

2018-01-01

Safety concern is one of the core issues that deter people from bicycling in the US. Earlier studies have explored the associations between intersection design characteristics and bicyclist safety perceptions. Research shows that there are significan...

Influence of Exercise Intensity for Improving Depressed Mood in Depression: A Dose-Response Study.

Science.gov (United States)

Meyer, Jacob D; Koltyn, Kelli F; Stegner, Aaron J; Kim, Jee-Seon; Cook, Dane B

2016-07-01

Exercise effectively improves mood in major depressive disorder (MDD), but the optimal exercise stimulus to improve depressed mood is unknown. To determine the dose-response relationship of acute exercise intensity with depressed mood responses to exercise in MDD. We hypothesized that the acute response to exercise would differ between light, moderate, and hard intensity exercise with higher intensities yielding more beneficial responses. Once weekly, 24 women (age: 38.6±14.0) diagnosed with MDD underwent a 30-minute session at one of three steady-state exercise intensities (light, moderate, hard; rating of perceived exertion 11, 13 or 15) or quiet rest on a stationary bicycle. Depressed mood was evaluated with the Profile of Mood States before, 10 and 30 minutes post-exercise. Exercise reduced depressed mood 10 and 30 minutes following exercise, but this effect was not influenced by exercise intensity. Participants not currently taking antidepressants (n=10) had higher baseline depression scores, but did not demonstrate a different antidepressant response to exercise compared to those taking antidepressants. To acutely improve depressed mood, exercise of any intensity significantly improved feelings of depression with no differential effect following light, moderate, or hard exercise. Pharmacological antidepressant usage did not limit the mood-enhancing effect of acute exercise. Acute exercise should be used as a symptom management tool to improve mood in depression, with even light exercise an effective recommendation. These results need to be replicated and extended to other components of exercise prescription (e.g., duration, frequency, mode) to optimize exercise guidelines for improving depression. Copyright © 2016. Published by Elsevier Ltd.

An expert judgment model applied to estimating the safety effect of a bicycle facility.

Science.gov (United States)

Leden, L; Gårder, P; Pulkkinen, U

2000-07-01

This paper presents a risk index model that can be used for assessing the safety effect of countermeasures. The model estimates risk in a multiplicative way, which makes it possible to analyze the impact of different factors separately. Expert judgments are incorporated through a Bayesian error model. The variance of the risk estimate is determined by Monte-Carlo simulation. The model was applied to assess the safety effect of a new design of a bicycle crossing. The intent was to gain safety by raising the crossings to reduce vehicle speeds and by making the crossings more visible by painting them in a bright color. Before the implementations, bicyclists were riding on bicycle crossings of conventional Swedish type, i.e. similar to crosswalks but delineated by white squares rather than solid lines or zebra markings. Automobile speeds were reduced as anticipated. However, it seems as if the positive effect of this was more or less canceled out by increased bicycle speeds. The safety per bicyclist was still improved by approximately 20%. This improvement was primarily caused by an increase in bicycle flow, since the data show that more bicyclists at a given location seem to benefit their safety. The increase in bicycle flow was probably caused by the new layout of the crossings since bicyclists perceived them as safer and causing less delay. Some future development work is suggested. Pros and cons with the used methodology are discussed. The most crucial parameter to be added is probably a model describing the interaction between motorists and bicyclists, for example, how risk is influenced by the lateral position of the bicyclist in relation to the motorist. It is concluded that the interaction seems to be optimal when both groups share the roadway.

The Role of Exercise Testing in the Modern Management of Pulmonary Arterial Hypertension

Directory of Open Access Journals (Sweden)

Martin K. Johnson

2014-05-01

Full Text Available A culture of exercise testing is firmly embedded in the management of pulmonary arterial hypertension (PAH but its clinical relevance and utility have recently been under some debate. The six minute walk test (6MWT has been used as a primary outcome measure to enable the licensing of many of the medications used for this condition. Recent reviews have questioned the validity of this test as a surrogate of clinical outcomes. At the same time, other questions are emerging where exercise testing may be the solution. With the rise in understanding of genetic markers of idiopathic PAH (IPAH, the screening of an otherwise healthy population for incipient pulmonary hypertension (PH will be required. The proliferation in treatment choices and identification of populations with PH where PAH treatment is not indicated, such as left heart and lung disease, requires more definitive differentiation from patients with PAH. There is a continuing question about the existence and clinical relevance of exercise induced PAH as a cause of unexplained dyspnoea and fatigue and as a latent phase of resting PH. This review presents a summary and critical analysis of the current role of exercise testing in PAH and speculates on future trends.

Effect of once a week endurance exercise on fitness status in sedentary subjects.

Science.gov (United States)

Hiruntrakul, Ashira; Nanagara, Ratanavadee; Emasithi, Alongkot; Borer, Katarina T

2010-09-01

To study whether 3-months aerobic exercise training at moderate intensity once a week can increase fitness status in healthy sedentary young men. Randomized controlled study was performed in 37 sedentary young men, 18 to 25 years old. The exercise group (19) was assigned to work on bicycle ergometry at 60% of maximal effort, once a week for 12 weeks. The control group (18) lived a normal life style. Before and after training, aerobic fitness (VO2(max)), resting heart rate, lipid profile, and isokinetic power and strength of shoulder and knee were evaluated. In the exercise group, there was a significant increase in most fitness parameters compared with control, VO2(max) (19.7%), isokinetic power and strength of shoulder and knee (14.9%), and resting heart rate decreased (7.4%). Moderate-intensity training once a week for at least 12 weeks was sufficient to increase aerobic fitness in sedentary young men. This low frequency of exercise training may be used to encourage sedentary individuals for more compliance with physical activity.

Reliability Of Kraus-Weber Exercise Test As An Evaluation Tool In ...

African Journals Online (AJOL)

Reliability Of Kraus-Weber Exercise Test As An Evaluation Tool In Low Back ... strength and flexibility of the back, abdominal, psoas and hamstring muscles. ... Keywords: Kraus-Weber test, low back pain, muscle flexibility, muscle strength.

Exercise does not produce hypoalgesia when performed immediately after a painful stimulus.

Science.gov (United States)

Gajsar, Hannah; Nahrwold, Katharina; Titze, Christina; Hasenbring, Monika I; Vaegter, Henrik B

2018-04-25

Exercise-induced hypoalgesia (EIH) and conditioned pain modulation (CPM) are assumed to reflect descending pain inhibition. Potential interactions between EIH and CPM may be important in the therapy of chronic pain, as reduced CPM and increased pain after exercise are frequently observed. This study compared the EIH response after CPM was activated using a cold pressor task with the EIH response after a control condition. Thirty-one participants (age: 27.7±9.8; 15 female) completed two sessions: a cold pressor task (CPT) session, i.e. testing EIH with preceding CPM activation induced using a 2 min CPT at approximately 2°C, and a control session, i.e. testing EIH after a control condition (2 min of quiet rest). EIH was induced using a 15 min bicycling exercise at a target heart rate corresponding to 75% VO2 max. Repeated measures ANOVAs on pressure pain thresholds (PPTs) at the hand, back and leg were used to determine the effects of exercise after the cold pressor test and control condition. Furthermore, correlations between CPM and EIH, in the CPT session as well as control session, were calculated at each assessment site. A significant time x condition interaction (F(1, 30)=43.61, pCPM at the hand (r=0.37, p=0.043). There was a moderate negative correlation of EIH in the CPT session and CPM at the hand (r=-0.50, p=0.004), and smaller negative correlations at the back (r=-0.37, p=0.036) and at the leg (r=-0.35, p=0.054). Attenuated EIH after the CPM activation in comparison to a control condition suggests that EIH and CPM may share underlying pain inhibitory mechanisms on a systemic level. This assumption is further supported by the finding of small to moderate significant correlations between EIH and CPM at the hand. The attenuated EIH response furthermore suggests that these mechanisms are exhaustible, i.e. that its effects decline after a certain amount of inhibition. In patients with chronic pain, assessing the current capacity of the descending pain

Efficiency of choice set generation methods for bicycle routes

DEFF Research Database (Denmark)

Halldórsdóttir, Katrín; Rieser-Schussler, Nadine; Axhausen, Kay W.

2014-01-01

for scenic routes, dedicated cycle lanes, and road type. Data consisted of 778 bicycle trips traced by GPS and carried out by 139 persons living in the Greater Copenhagen Area, in Denmark. Results suggest that both the breadth first search on link elimination and the doubly stochastic generation function...

Influence of the incremental step size in work rate on exercise response and gas exchange in patients with pulmonary hypertension.

Science.gov (United States)

Gläser, Sven; Lodziewski, Sven; Koch, Beate; Opitz, Christian F; Völzke, Henry; Ewert, Ralf

2008-02-23

Cardiopulmonary exercise testing (CPET) has become increasingly important as a routine procedure in daily clinical work. So far, it is generally accepted that an individualized exercise protocol with exercise duration of 6 to 12 minutes is preferable to assess maximal exercise performance. The aim of this study was to compare an individualized NYHA adapted exercise protocol with a fixed standard protocol in patients with severe pulmonary arterial hypertension. Twenty-two patients (17 female, 5 male; mean age 49 +/- 14 yrs) underwent symptom limited CPET on a bicycle. On two consecutive days each subject performed a stepwise CPET according to a modified Jones protocol (16 Watt per minute stages) as well as an individualized NYHA adapted protocol with 5 or 10 Watt/min stages in a randomized order. Oxygen uptake at peak exercise (peakVO2) and anaerobic threshold (VO2AT), maximal ventilation (VE), breathing reserve (VE/MVV), ventilatory efficiency (VE vs. VCO2 slope), exercise time, maximal power and work rate were assessed and compared between both protocols. Comparing both, adapted NYHA protocol and standardized Jones protocol, we found significant differences in maximal power (56.7 +/- 19 W vs. 74 +/- 18 W; p rate, VE, VE/MVV, peakVO2, VO2AT and VE vs. VCO2 slope. Variations of incremental step size during CPET significantly affect exercise time and maximal power, whereas relevant parameters for clinical judgement and prognosis such as oxygen uptake, ventilation and ventilatory efficiency remain unchanged. These findings have practical implications for the exercise evaluation of patients with pulmonary hypertension. To reach maximal results for ventilation, oxygen uptake and gas exchange an individualization of incremental step size appears not to be mandatory.

Exercise Capacity and Functional Performance in Heart Failure Patients Supported by a Left Ventricular Assist Device at Discharge From Inpatient Rehabilitation.

Science.gov (United States)

Schmidt, Thomas; Bjarnason-Wehrens, Birna; Bartsch, Petra; Deniz, Ezin; Schmitto, Jan; Schulte-Eistrup, Sebastian; Willemsen, Detlev; Reiss, Nils

2018-01-01

Adequate physical and functional performance is an important prerequisite for renewed participation and integration in self-determined private and (where appropriate) professional lives following left ventricular assist device (LVAD) implantation. During cardiac rehabilitation (CR), individually adapted exercise programs aim to increase exercise capacity and functional performance. A retrospective analysis of cardiopulmonary exercise capacity and functional performance in LVAD patients at discharge from a cardiac rehabilitation program was conducted. The results from 68 LVAD patients (59 males, 9 females; 55.9 ± 11.7 years; 47 HVAD, 2 MVAD, 15 HeartMate II, 4 HeartMate 3, and 4 different implanting centers) were included in the analysis. Exercise capacity was assessed using a cardiopulmonary exercise test on a bicycle ergometer (ramp protocol; 10 W/min). The 6-min walk test was used to determine functional performance. At discharge from CR (53 ± 17 days after implantation), the mean peak work load achieved was 62.2 ± 19.3 W (38% of predicted values) or 0.79 ± 0.25 W/kg body weight. The mean cardiopulmonary exercise capacity (relative peak oxygen uptake) was 10.6 ± 5.3 mL/kg/min (37% of predicted values). The 6-min walk distance improved significantly during CR (325 ± 106 to 405 ± 77 m; P exercise capacity remains considerably restricted. In contrast, functional performance, measured by the 6-min walk distance, reaches an acceptable level. Light everyday tasks seem to be realistically surmountable for patients, making discharge from inpatient rehabilitation possible. Long-term monitoring is required in order to evaluate the situation and how it develops further. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Methodological proposal for the implementation of shared bicycle applied to the Brazilian context

Energy Technology Data Exchange (ETDEWEB)

Espana, J.P.; Barbosa, P.

2016-07-01

The main objective of this study is to analyze the bicycle rental system in the Federal District {sup B}ike Brasilia{sup .} It aims to identify guidelines that supported the application process and consensus, disagreements and guidelines established by the Institute for Policies and Development in Transportation - ITDP and relate those listed by Zhang regarding rented bikes systems. This is an exploratory study based on the strategy of document analysis and its secondary sources: institutional documents, basic design, procurement and other official documents made exclusively for this study. To support the discussion, a systematic literature review of the rules describing specially: sustainability, transport, urban mobility, bicycle rental and environment. The results reveal that while some of the parameters and indicators of efficiency are met on time, the bicycle sharing system of the city of Brasilia, has weaknesses that can lead to inefficiency and impracticality of maintaining and expanding such services. On the other hand, Bike Brasilia partially fulfills the principles enumerated by Zhang and lacks improvement in the steps for the successful operation of the system. (Author)

Peptides derivatized with bicyclic quaternary ammonium ionization tags. Sequencing via tandem mass spectrometry.

Science.gov (United States)

Setner, Bartosz; Rudowska, Magdalena; Klem, Ewelina; Cebrat, Marek; Szewczuk, Zbigniew

2014-10-01

Improving the sensitivity of detection and fragmentation of peptides to provide reliable sequencing of peptides is an important goal of mass spectrometric analysis. Peptides derivatized by bicyclic quaternary ammonium ionization tags: 1-azabicyclo[2.2.2]octane (ABCO) or 1,4-diazabicyclo[2.2.2]octane (DABCO), are characterized by an increased detection sensitivity in electrospray ionization mass spectrometry (ESI-MS) and longer retention times on the reverse-phase (RP) chromatography columns. The improvement of the detection limit was observed even for peptides dissolved in 10 mM NaCl. Collision-induced dissociation tandem mass spectrometry of quaternary ammonium salts derivatives of peptides showed dominant a- and b-type ions, allowing facile sequencing of peptides. The bicyclic ionization tags are stable in collision-induced dissociation experiments, and the resulted fragmentation pattern is not significantly influenced by either acidic or basic amino acid residues in the peptide sequence. Obtained results indicate the general usefulness of the bicyclic quaternary ammonium ionization tags for ESI-MS/MS sequencing of peptides. Copyright © 2014 John Wiley & Sons, Ltd.

The usefulness of GPS bicycle tracking data for evaluating the impact of infrastructure change on cycling behaviour.

Science.gov (United States)

Heesch, Kristiann C; Langdon, Michael

2016-02-01

Issue addressed A key strategy to increase active travel is the construction of bicycle infrastructure. Tools to evaluate this strategy are limited. This study assessed the usefulness of a smartphone GPS tracking system for evaluating the impact of this strategy on cycling behaviour. Methods Cycling usage data were collected from Queenslanders who used a GPS tracking app on their smartphone from 2013-2014. 'Heat' and volume maps of the data were reviewed, and GPS bicycle counts were compared with surveillance data and bicycle counts from automatic traffic-monitoring devices. Results Heat maps broadly indicated that changes in cycling occurred near infrastructure improvements. Volume maps provided changes in counts of cyclists due to these improvements although errors were noted in geographic information system (GIS) geo-coding of some GPS data. Large variations were evident in the number of cyclists using the app in different locations. These variations limited the usefulness of GPS data for assessing differences in cycling across locations. Conclusion Smartphone GPS data are useful in evaluating the impact of improved bicycle infrastructure in one location. Using GPS data to evaluate differential changes in cycling across multiple locations is problematic when there is insufficient traffic-monitoring devices available to triangulate GPS data with bicycle traffic count data. So what? The use of smartphone GPS data with other data sources is recommended for assessing how infrastructure improvements influence cycling behaviour.

Oxidative stress in response to aerobic and anaerobic power testing: influence of exercise training and carnitine supplementation.

Science.gov (United States)

Bloomer, Richard J; Smith, Webb A

2009-01-01

The purpose of this study is to compare the oxidative stress response to aerobic and anaerobic power testing, and to determine the impact of exercise training with or without glycine propionyl-L-carnitine (GPLC) in attenuating the oxidative stress response. Thirty-two subjects were assigned (double blind) to placebo, GPLC-1 (1g PLC/d), GPLC-3 (3g PLC/d) for 8 weeks, plus aerobic exercise. Aerobic (graded exercise test: GXT) and anaerobic (Wingate cycle) power tests were performed before and following the intervention. Blood was taken before and immediately following exercise tests and analyzed for malondialdehyde (MDA), hydrogen peroxide (H2O2), and xanthine oxidase activity (XO). No interaction effects were noted. MDA was minimally effected by exercise but lower at rest for both GPLC groups following the intervention (p = 0.044). A time main effect was noted for H2O2 (p = 0.05) and XO (p = 0.003), with values increasing from pre- to postexercise. Both aerobic and anaerobic power testing increase oxidative stress to a similar extent. Exercise training plus GPLC can decrease resting MDA, but it has little impact on exercise-induced oxidative stress biomarkers.

Effect of exercise on erythrocyte count and blood activity concentration after technetium-99m in vivo red blood cell labeling

International Nuclear Information System (INIS)

Konstom, M.A.; Tu'meh, S.; Wynne, J.; Beck, J.R.; Kozlowski, J.; Holman, B.L.

1982-01-01

The effects of exercise on blood radiotracer concentration after technetium-99m in vivo red blood cell labeling was studied. After red blood cell labeling, 13 subjects underwent maximal supine bicycle exercise. Radioactivity, analyzed with a well counter, was measured in heparinized venous blood samples drawn at rest and during peak exercise. Changes in activity were compared with changes in erythrocyte count. Activity and erythrocyte counts increased in erythrocyte count (r=0.78), but did not correlate with either duration of exercise or maximal heart rate. Twenty minutes after termination of exercise, activity and erythrocyte count had decreased from peak exercise values but remained higher than preexercise values. In nine nonexercised control subjects, samples drawn 20 minutes apart showed no change in activity or in erythrocyte count. It was concluded that exercise increases blood activity, primarily because of an increase in erythrocyte count. During radionuclide ventriculography, blood activity must be measured before and after any intervention, particularly exercise, before a change in left ventricular activity can be attributed to a change in left ventricular volume

An experiment on rider stability while mounting : comparing middle-aged and elderly cyclists on pedelecs and conventional bicycles.

NARCIS (Netherlands)

Twisk, D.A.M. Platteel, S. & Lovegrove, G.R.

2017-01-01

Pedelecs, popular among elderly cyclists, are associated with a higher injury risk than conventional bicycles. About 17% of these injuries are due to falls while (dis)mounting. Using instrumented bicycles, this study aimed to identify factors contributing to the stability of self-chosen mounting

Effect of exercise on deposition and subsequent retention of inhaled particles

International Nuclear Information System (INIS)

Bennett, W.D.; Messina, M.S.; Smaldone, G.C.

1985-01-01

To investigate the effect of exercise and its associated increase in ventilation on the deposition and subsequent retention of inhaled particles, we measured the fractional and regional lung deposition of a radioactively tagged (/sup 99m/Tc) monodisperse aerosol (2.6 microns mass median aerodynamic diam) in normal human subjects at rest and while exercising on a bicycle ergometer. Breath-by-breath deposition fraction (DF) was measured throughout the aerosol exposures by Tyndallometry. Following each exposure gamma camera analysis was used to 1) determine the regional distribution of deposited particles and 2) monitor lung retention for 2.5 h and again at 24 h. We found that DF was unchanged between ventilation at rest (6-10 l/min) and exercise (32-46 l/min). Even though mouth deposition was enhanced with exercise, it was not large enough to produce a significant difference in the deposition fraction of the lung (DFL) between resting and exercise exposures. The central-to-peripheral distribution of deposited aerosol was larger for the exercise vs. resting exposure, reflecting a shift of particle deposition to more central bronchial airways. Apical-to-basal distribution was not different for the two exposures. Retention at 2.5 h and 24 h (R24) was reduced following the exercise vs. the resting exposure, consistent with greater bronchial deposition during exercise. The product of DFL and R24 gave a measure of fractional burden at 24 h (B24), i.e., the fraction of inhaled aerosol residing in the lungs 24 h after exposure. B24 was not significantly different between rest and exercise exposures

The Intermodal Bike: multi-modal integration of cycling mobility through product and process innovations in bicycle design.

Science.gov (United States)

Tosi, Francesca; Belli, Alessandro; Rinaldi, Alessandra; Tucci, Grazia

2012-01-01

The paper presents the early results of the UE-FP7 project "The Intermodal Bike". The research aim is to provide a super-compactable, super-lightweight folding bicycle as a realistic solution to graft the cycling mode onto the root of the public or private transportation systems. The folding bikes now on the international market reach weighs between 12-15 kg, with a variable footprint but occupying -when compacted- an average volume of about 100 liters. To encourage the use of this vehicle and to extend it to a larger number of users with different characteristics, the research project has set its goal in increasing as possible compactness and light weight, creating a bicycle with a volume when compacted of 20 liters (reduction factor =5), with a shape of 48 × 36 × 12 cm and a weight of 5 kg. max., ensuring stability and improving vehicle usability and efficiency, during the ride and in the phase of bike folding. To achieve this goal ergonomic and usability tests have been carried out. The tests allowed to find a posture that would ensure efficiency and comfort in the ride to as many users as possible. Parallel tests were made on the vehicle usability in the urban transport system and intermodal. The need for light weight has required special studies on the optimization of the vehicle's architecture and research on super-lightweight materials.

Exaggerated blood pressure response to early stages of exercise stress testing and presence of hypertension.

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Schultz, Martin G; Picone, Dean S; Nikolic, Sonja B; Williams, Andrew D; Sharman, James E

2016-12-01

Exaggerated exercise blood pressure (EEBP) recorded during exercise testing at moderate-intensity is independently associated with cardiovascular mortality. It is hypothesized that EEBP may be indicative of underlying hypertension unnoticed by standard clinic (resting) BP measures (thus explaining increased mortality risk), but this has never been confirmed by association with hypertension defined using ambulatory BP monitoring, which was the aim of this study. Cross-sectional study. 100 consecutive patients free from coronary artery disease (aged 56±9 years, 72% male) underwent clinically indicated exercise stress testing. Exercise BP was recorded at each stage of the Bruce protocol. Presence of hypertension was defined as 24-hour systolic BP ≥130mmHg or daytime systolic BP ≥135mmHg. Exercise systolic BP at stage 1 and 2 of the test was significantly associated with the presence of hypertension (P130mmHg (AUC=0.752, 95% CI's 0.649-0.846, P150mmHg predicting hypertension independently of age, sex and in-clinic hypertension status (OR=4.83, 95% CI's 1.62-14.39, P=0.005). Irrespective of resting BP, systolic BP ≥150mmHg during early stages of the Bruce exercise stress test is associated with presence of hypertension. EEBP should be a warning signal to health/exercise professionals on the presence of hypertension and the need to provide follow up care to reduce cardiovascular risk. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The PurdueTracer: An Energy-Efficient Human-Powered Hydraulic Bicycle with Flexible Operation and Software Aids

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Gianluca Marinaro

2018-01-01

Full Text Available Hydrostatic transmissions (HT are widely applied to heavy-duty mobile applications because of the advantages of layout flexibility, power to weight ratio, and ease of control. Though applications of fluid power in light-duty vehicles face challenges, including the unavailability of off-the-shelf components suitable to the power scale, there are potential advantages for HTs in human-powered vehicles, such as bicycles, the most important one being the energy-saving advantage achievable through regenerative braking in a hybrid HT. This paper describes an innovative design for a hydraulic hybrid bicycle, i.e., the PurdueTracer. The PurdueTracer is an energy-efficient human-powered hydraulic bicycle with flexible operation and software aids. An open-circuit hydraulic hybrid transmission allows PurdueTracer to operate in four modes: Pedaling, Charging, Boost, and Regeneration, to satisfy users’ need for different riding occasions. An aluminum chassis that also functions as a system reservoir was customized for the PurdueTracer to optimize the durability, riding comfort, and space for components. The selection of the hydraulic components was performed by creating a model of the bicycle in AMESim simulation software and conducting a numerical optimization based on the model. The electronic system equipped users with informative feedback showing the bicycle performance, intuitive execution of functions, and comprehensive guidance for operation. This paper describes the design approach and the main results of the PurdueTracer, which also won the 2017 National Fluid Power Association Fluid Power Vehicle Challenge. This championship serves to prove the excellence of this vehicle in terms of effectiveness, efficiency, durability, and novelty.

Bronchial provocation testing does not detect exercise-induced laryngeal obstruction.

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Walsted, Emil Schwarz; Hull, James H; Sverrild, Asger; Porsbjerg, Celeste; Backer, Vibeke

2017-01-02

Exercise-induced laryngeal obstruction (EILO) is a key differential diagnosis for asthma in the presence of exertional respiratory symptoms. Continuous laryngoscopy during exercise (CLE), the current gold standard diagnostic test for EILO, has practical limitations. We aimed to establish if inspiratory flow data obtained during standard bronchoprovocation testing, to establish the presence of extra-thoracic hyper-responsiveness, may prove diagnostic for EILO and thus preclude requirement for CLE testing. We consecutively evaluated 37 adult subjects with exertional dyspnea and possible asthma referred over 6 months. All subjects received comprehensive assessment including a detailed clinical evaluation; pulmonary function testing, indirect and direct bronchial provocation testing, and CLE testing. Out of 37 subjects, moderate or severe EILO was diagnosed in 8 subjects (22%, all female) while 5 (14%) had both asthma and EILO. There was no correlation between degree of EILO during CLE and mean decrease in forced inspiratory flow (%FIF 50 ) obtained during neither the Methacholine (r = -0.15; p = 0.38) nor Mannitol (r = 0.04; p = 0.84) provocation tests. Inspiratory flow parameters obtained during bronchoprovocation tests did not reliably detect EILO. It remains that CLE is an important and key investigation modality in establishing a secure diagnosis of EILO.

Exercise in the fasted state facilitates fibre type-specific intramyocellular lipid breakdown and stimulates glycogen resynthesis in humans

DEFF Research Database (Denmark)

De Bock, K.; Richter, Erik; Russell, A.P.

2005-01-01

g (kg bw)-1 h-1) exercise. In both conditions, subjects ingested 5 g carbohydrates per kg body weight during recovery. Fibre type-specific relative IMTG content was determined by Oil red O staining in needle biopsies from m. vastus lateralis before, immediately after and 4 h after exercise. During F...... sessions with an interval of 3 weeks. In each session subjects performed 2 h of constant-load bicycle exercise (~75% VO2,max), followed by 4 h of controlled recovery. On one occasion they exercised after an overnight fast (F), and on the other (CHO) they received carbohydrates before (~150 g) and during (1...... but not during CHO, the exercise bout decreased IMTG content in type I fibres from 18 ± 2% to 6 ± 2% (P = 0.007) area lipid staining. Conversely, during recovery, IMTG in type I fibres decreased from 15 ± 2% to 10 ± 2% in CHO, but did not change in F. Neither exercise nor recovery changed IMTG in type IIa fibres...

State anxiety, psychological stress and positive well-being responses to yoga and aerobic exercise in people with schizophrenia: a pilot study.

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Vancampfort, Davy; De Hert, Marc; Knapen, Jan; Wampers, Martien; Demunter, Hella; Deckx, Seppe; Maurissen, Katrien; Probst, Michel

2011-01-01

Worsening of schizophrenia symptoms is related to stress and anxiety. People with schizophrenia often experience difficulties in coping with stress and possess a limited repertoire of coping strategies. A randomised comparative trial was undertaken in patients with schizophrenia to evaluate changes in state anxiety, psychological stress and subjective well-being after single sessions of yoga and aerobic exercise compared with a control condition. Forty participants performed a single 30-min yoga session, 20-min of aerobic exercise on a bicycle ergometre at self-selected intensity and a 20-min no exercise control condition in random order. After single sessions of yoga and aerobic exercise individuals with schizophrenia or schizoaffective disorder showed significantly decreased state anxiety (p stress (p exercise control condition. Effect sizes ranged from 0.82 for psychological stress after aerobic exercise to 1.01 for state anxiety after yoga. The magnitude of the changes did not differ significantly between yoga and aerobic exercise. People with schizophrenia and physiotherapists can choose either yoga or aerobic exercise in reducing acute stress and anxiety taking into account the personal preference of each individual.

Exertional dyspnoea in COPD: the clinical utility of cardiopulmonary exercise testing

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Denis E. O'Donnell

2016-09-01

Full Text Available Activity-related dyspnoea is often the most distressing symptom experienced by patients with chronic obstructive pulmonary disease (COPD and can persist despite comprehensive medical management. It is now clear that dyspnoea during physical activity occurs across the spectrum of disease severity, even in those with mild airway obstruction. Our understanding of the nature and source of dyspnoea is incomplete, but current aetiological concepts emphasise the importance of increased central neural drive to breathe in the setting of a reduced ability of the respiratory system to appropriately respond. Since dyspnoea is provoked or aggravated by physical activity, its concurrent measurement during standardised laboratory exercise testing is clearly important. Combining measurement of perceptual and physiological responses during exercise can provide valuable insights into symptom severity and its pathophysiological underpinnings. This review summarises the abnormal physiological responses to exercise in COPD, as these form the basis for modern constructs of the neurobiology of exertional dyspnoea. The main objectives are: 1 to examine the role of cardiopulmonary exercise testing (CPET in uncovering the physiological mechanisms of exertional dyspnoea in patients with mild-to-moderate COPD; 2 to examine the escalating negative sensory consequences of progressive respiratory impairment with disease advancement; and 3 to build a physiological rationale for individualised treatment optimisation based on CPET.

Usage Patterns of Electric Bicycles: An Analysis of the WeBike Project

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Christian Gorenflo

2017-01-01

Full Text Available This paper presents an analysis of data collected through the Waterloo WeBike project: a field trial in which over 30 sensor-equipped electric bicycles (e-bikes were given to members of the University of Waterloo for personal use. Our dataset includes e-bike trips and battery charging sessions spanning nearly three years, from summer 2014 until spring 2017. We also conducted three surveys both before and during the trial. Our main findings were that the primary purpose of the e-bikes in our trial was for commuting, with most trips lasting less than 20 minutes and most trips taking place in the summer months. Our battery charging analysis revealed no evidence of range anxiety, and our analysis of survey results showed little correlation between anticipated and actual use. Furthermore, when asked about their opinions about various modes of transportation, our participants rated regular bicycles higher than e-bikes even after becoming familiar with e-bikes through the field trial. Based on our analysis, we draw several conclusions, including the fact that the general population in Canada is still unaware of e-bikes and their potential. Moreover, e-bike manufacturers should target sales to nonbike users, such as seniors, rather than trying to displace sales of regular bicycles.

Possible in vivo tolerance of human polymorphonuclear neutrophil to low-grade exercise-induced endotoxaemia

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G. Camus

1998-01-01

Full Text Available To address the question of whether translocation of bacterial lipopolysaccharide (LPS into the blood could be involved in the process of exercise-induced polymorphonuclear neutrophil (PMN activation, 12 healthy male subjects who took part in a sprint triathlon (1.5 km river swim, 40 km bicycle race, 10 km road race were studied. While there was no detectable amount of endotoxin in the blood samples drawn at rest, exercise was followed by the appearance of circulating endotoxin molecules at the end of competition in four subjects, and after one and 24 h recovery in three and seven athletes, respectively. The concentrations of plasma granulocyte myeloperoxidase ([MPO], were significantly higher immediately after exercise and one hour later than baseline values (P<0.001. This variable returned to pre-race levels the day after exercise, despite the presence of detectable amounts of LPS, at that time, in seven athletes. The absence of significant correlation (r=0.26;P=0.383 and temporal association between [MPO]and plasma endotoxin levels led us to conclude that endotoxaemia was not involved in the process of exercise-induced PMN degranulation observed in our subjects.

Municipal investment in off-road trails and changes in bicycle commuting in Minneapolis, Minnesota over 10 years: a longitudinal repeated cross-sectional study.

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Hirsch, Jana A; Meyer, Katie A; Peterson, Marc; Zhang, Le; Rodriguez, Daniel A; Gordon-Larsen, Penny

2017-02-13

We studied the effect of key development and expansion of an off-road multipurpose trail system in Minneapolis, Minnesota between 2000 and 2007 to understand whether infrastructure investments are associated with increases in commuting by bicycle. We used repeated measures regression on tract-level (N = 116 tracts) data to examine changes in bicycle commuting between 2000 and 2008-2012. We investigated: 1) trail proximity measured as distance from the trail system and 2) trail potential use measured as the proportion of commuting trips to destinations that might traverse the trail system. All analyses (performed 2015-2016) adjusted for tract-level sociodemographic covariates and contemporaneous cycling infrastructure changes (e.g., bicycle lanes). Tracts that were both closer to the new trail system and had a higher proportion of trips to destinations across the trail system experienced greater 10-year increases in commuting by bicycle. Proximity to off-road infrastructure and travel patterns are relevant to increased bicycle commuting, an important contributor to overall physical activity. Municipal investment in bicycle facilities, especially off-road trails that connect a city's population and its employment centers, is likely to lead to increases in commuting by bicycle.

Prospective evaluation of a new protocol for the provisional use of perfusion imaging with exercise stress testing

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Duvall, W.L. [Hartford Hospital, Division of Cardiology (Henry Low Heart Center), Hartford, CT (United States); Mount Sinai Medical Center, Division of Cardiology (Mount Sinai Heart), New York, NY (United States); Savino, John A.; Levine, Elliot J.; Croft, Lori B.; Henzlova, Milena J. [Mount Sinai Medical Center, Division of Cardiology (Mount Sinai Heart), New York, NY (United States); Hermann, Luke K. [Mount Sinai Medical Center, Department of Emergency Medicine, New York, NY (United States)

2014-11-04

Previous literature suggests that myocardial perfusion imaging (MPI) adds little to the prognosis of patients who exercise >10 metabolic equivalents (METs) during stress testing. With this in mind, we prospectively tested a provisional injection protocol in emergency department (ED) patients presenting for the evaluation of chest pain in which a patient would not receive an injection of radioisotope if adequate exercise was achieved without symptoms and a negative ECG response. All patients who presented to the ED over a 5-year period who were referred for stress testing as part of their ED evaluation were included. Patients considered for a provisional protocol were: exercise stress, age <65 years, no known coronary artery disease, and an interpretable rest ECG. Criteria for not injecting included a maximal predicted heart rate ≥85 %, ≥10 METs of exercise, no anginal symptoms during stress, and no ECG changes. Groups were compared based on stress test results, all-cause and cardiac mortality, follow-up cardiac testing, subsequent revascularization, and cost. A total of 965 patients were eligible with 192 undergoing exercise-only and 773 having perfusion imaging. After 41.6 ± 19.6 months of follow-up, all-cause mortality was similar in the exercise-only versus the exercise plus imaging group (2.6 % vs. 2.1 %, p = 0.59). There were no cardiac deaths in the exercise-only group. At 1 year there was no difference in the number of repeat functional stress tests (1.6 % vs. 2.1 %, p = 0.43), fewer angiograms (0 % vs. 4.0 %, p = 0.002), and a significantly lower cost (65 ± 332 vs 506 ± 1,991, p = 0.002; values are in US dollars) in the exercise-only group. The radiation exposure in the exercise plus imaging group was 8.4 ± 2.1 mSv. A provisional injection protocol has a very low mortality, few follow-up diagnostic tests, and lower cost compared to standard imaging protocols. If adopted it would decrease radiation exposure, save time and decrease health-care costs

Prospective evaluation of a new protocol for the provisional use of perfusion imaging with exercise stress testing.

Science.gov (United States)

Duvall, W Lane; Savino, John A; Levine, Elliot J; Hermann, Luke K; Croft, Lori B; Henzlova, Milena J

2015-02-01

Previous literature suggests that myocardial perfusion imaging (MPI) adds little to the prognosis of patients who exercise >10 metabolic equivalents (METs) during stress testing. With this in mind, we prospectively tested a provisional injection protocol in emergency department (ED) patients presenting for the evaluation of chest pain in which a patient would not receive an injection of radioisotope if adequate exercise was achieved without symptoms and a negative ECG response. All patients who presented to the ED over a 5-year period who were referred for stress testing as part of their ED evaluation were included. Patients considered for a provisional protocol were: exercise stress, age heart rate ≥85%, ≥10 METs of exercise, no anginal symptoms during stress, and no ECG changes. Groups were compared based on stress test results, all-cause and cardiac mortality, follow-up cardiac testing, subsequent revascularization, and cost. A total of 965 patients were eligible with 192 undergoing exercise-only and 773 having perfusion imaging. After 41.6 ± 19.6 months of follow-up, all-cause mortality was similar in the exercise-only versus the exercise plus imaging group (2.6% vs. 2.1%, p = 0.59). There were no cardiac deaths in the exercise-only group. At 1 year there was no difference in the number of repeat functional stress tests (1.6% vs. 2.1%, p = 0.43), fewer angiograms (0% vs. 4.0%, p = 0.002), and a significantly lower cost ($65 ± $332 vs $506 ± $1,991, p = 0.002; values are in US dollars) in the exercise-only group. The radiation exposure in the exercise plus imaging group was 8.4 ± 2.1 mSv. A provisional injection protocol has a very low mortality, few follow-up diagnostic tests, and lower cost compared to standard imaging protocols. If adopted it would decrease radiation exposure, save time and decrease health-care costs without jeopardizing prognosis.

Prospective evaluation of a new protocol for the provisional use of perfusion imaging with exercise stress testing

International Nuclear Information System (INIS)

Duvall, W.L.; Savino, John A.; Levine, Elliot J.; Croft, Lori B.; Henzlova, Milena J.; Hermann, Luke K.

2015-01-01

Previous literature suggests that myocardial perfusion imaging (MPI) adds little to the prognosis of patients who exercise >10 metabolic equivalents (METs) during stress testing. With this in mind, we prospectively tested a provisional injection protocol in emergency department (ED) patients presenting for the evaluation of chest pain in which a patient would not receive an injection of radioisotope if adequate exercise was achieved without symptoms and a negative ECG response. All patients who presented to the ED over a 5-year period who were referred for stress testing as part of their ED evaluation were included. Patients considered for a provisional protocol were: exercise stress, age <65 years, no known coronary artery disease, and an interpretable rest ECG. Criteria for not injecting included a maximal predicted heart rate ≥85 %, ≥10 METs of exercise, no anginal symptoms during stress, and no ECG changes. Groups were compared based on stress test results, all-cause and cardiac mortality, follow-up cardiac testing, subsequent revascularization, and cost. A total of 965 patients were eligible with 192 undergoing exercise-only and 773 having perfusion imaging. After 41.6 ± 19.6 months of follow-up, all-cause mortality was similar in the exercise-only versus the exercise plus imaging group (2.6 % vs. 2.1 %, p = 0.59). There were no cardiac deaths in the exercise-only group. At 1 year there was no difference in the number of repeat functional stress tests (1.6 % vs. 2.1 %, p = 0.43), fewer angiograms (0 % vs. 4.0 %, p = 0.002), and a significantly lower cost (65 ± 332 vs 506 ± 1,991, p = 0.002; values are in US dollars) in the exercise-only group. The radiation exposure in the exercise plus imaging group was 8.4 ± 2.1 mSv. A provisional injection protocol has a very low mortality, few follow-up diagnostic tests, and lower cost compared to standard imaging protocols. If adopted it would decrease radiation exposure, save time and decrease health-care costs

Comparison of adenosine and treadmill exercise thallium-201 stress tests for the detection of coronary artery disease

International Nuclear Information System (INIS)

Abe, Shinya; Takeishi, Yasuchika; Chiba, Junya; Ikeda, Kozue; Tomoike, Hitonobu

1993-01-01

To determine the clinical usefulness of adenosine Tl-201 imaging for the evaluation of coronary artery disease, 22 patients with suspected coronary artery disease who underwent adenosine and exercise Tl-201 single photon emission computed tomography (SPECT) were studied. The peak levels of heart rate (83 vs 123 bpm, p<0.001), systolic blood pressure (124 vs 164 mmHg, p<0.001), diastolic blood pressure (70 vs 86 mmHg, p<0.01) and rate pressure products (10220 vs 20410 bpm x mmHg, p<0.001) were markedly smaller during adenosine infusion than during exercise. Segmental agreements between adenosine and exercise tests were 90% (218 of 242 segments) regarding the presence of perfusion defects and 89% (215 of 242 segments) regarding the presence of redistribution. Regional Tl-201 uptake (r=0.85, p<0.001) and the extent (r=0.75, p<0.001) and intensity (r=0.83, p<0.001) of Tl-201 defects during adenosine testing were closely correlated with those of exercise testing. Adenosine and exercise tests showed similar sensitivities for the identification of individual coronary stenosis (85% vs 78%). However, in patients who were unable to perform adequate exercise (maximal heart rate<120 bpm), the sensitivity of adenosine imaging tended to be higher than that of exercise imaging (92% vs 69%, p=0.07). Adenosine Tl-201 imaging is an alternative to the exercise test for assessing the severity and loci of coronary artery disease, especially in patients who are unable to perform adequate physical exercise. (author)

Long-Term Effect of Exercise Therapy and Patient Education on Impairments and Activity Limitations in People With Hip Osteoarthritis

DEFF Research Database (Denmark)

Svege, Ida; Fernandes, L.; Nordsletten, L

2016-01-01

fitness, walking capacity, and pain during walking in people with hip OA. Design. This was a secondary outcome analysis of a randomized clinical trial. Setting. The setting was a university hospital. Participants. One hundred nine people with clinically and radiographically evident hip OA were randomly...... consumption determined with the Astrand bicycle ergometer test, and distance and pain during the Six-Minute Walk Test (6MWT). Follow-up assessments were conducted 4, 10, and 29 months after enrollment by 5 physical therapists who were unaware of group allocations. Results. No significant group differences...... were found for ROM, muscle strength, predicted maximal oxygen consumption, or distance during the 6MWT over the follow-up period, but the exercise group had less pain during the 6MWT than the control group at 10 months (mean difference= –8.5 mm; 95% confidence interval= –16.1, –0.9) and 29 months (mean...

Distribution and predictors of exercise habits among pregnant women in the Danish National Birth Cohort.

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Juhl, M; Madsen, M; Andersen, A-M N; Andersen, P K; Olsen, J

2012-02-01

Physical activity is recommended during pregnancy, although strong evidence on reproductive health is lacking. We present exercise habits and predictors of exercise during pregnancy. From the Danish National Birth Cohort (1996-2002), 88,200 singleton pregnancies were analyzed in logistic regression. About one-third of the women exercised in early/mid pregnancy and slightly less in late pregnancy. Bicycling, swimming, and low-impact activities were most common. Exercising more than three times per week was strongly correlated with older age, being a student or out of work, eating disorders, moderate alcohol consumption, and a healthy diet. Multiparity, a normal or less good self-rated health, smoking, and a less health conscious diet were the strongest predictors of not doing exercise. Women of 25 years or older, with metabolic or psychiatric disorders, or who had received subfecundity treatment were more likely to increase their activity level substantially from early to late pregnancy than comparison groups. In conclusion, exercising during pregnancy correlated with a number of maternal characteristics. The findings may be used to identify pregnant women not likely to exercise, to target activities that may fit their needs, and, for research purposes, to identify adjustment variables or guide sensitivity analyses when data on confounders are lacking. © 2010 John Wiley & Sons A/S.

Metabolic and clinical comparative analysis of treadmill six-minute walking test and cardiopulmonary exercise testing in obese and eutrophic women

Directory of Open Access Journals (Sweden)

Luciana Di Thommazo-Luporini

Full Text Available BACKGROUND: Impaired exercise tolerance is directly linked to decreased functional capacity as a consequence of obesity. OBJECTIVES: To analyze and compare the cardiopulmonary, metabolic, and perceptual responses during a cardiopulmonary exercise test (CPX and a treadmill six-minute walking test (tread6MWT in obese and eutrophic women. METHOD: Twenty-nine female participants, aged 20-45 years were included. Fourteen were allocated to the obese group and 15 to the eutrophic group. Anthropometric measurements and body composition assessment were performed. RESULTS: In both tests, obese women presented with significantly higher absolute oxygen uptake, minute ventilation, and systolic and diastolic blood pressure; they also presented with lower speed, distance walked, and oxygen uptake corrected by the weight compared to eutrophics. During the maximal exercise test, perceived dyspnea was greater and the respiratory exchange ratio was lower in obese subjects compared to eutrophics. During the submaximal test, carbon dioxide production, tidal volume, and heart rate were higher in obese subjects compared to eutrophic women. When analyzing possible correlations between the CPX and the tread6MWT at peak, there was a strong correlation for the variable heart rate and a moderate correlation for the variable oxygen uptake. The heart rate obtained in the submaximal test was able to predict the one obtained in the maximal test. Bland-Altman plots demonstrated the agreement between both tests to identify metabolic and physiological parameters at peak exercise. CONCLUSIONS: The six-minute walking test induced ventilatory, metabolic, and cardiovascular responses in agreement with the maximal testing. Thus, the six-minute walking test proves to be important for functional evaluation in the physical therapy routine.

Hydrolysis of strained bridgehead bicyclic vinyl ethers and sulfides

International Nuclear Information System (INIS)

Chwang, W.K.; Kresge, A.J.; Wiseman, J.R.

1979-01-01

Rates of hydrolysis of the bridgehead bicyclic vinyl ether 9-oxabicyclo[3.3.1]non-1-ene(6) and its vinyl sulfide counterpart 9-thiabicyclo[3.3.1]non-1-ene(7), catalyzed by the hydronium ion, were measured in H 2 O and in D 2 O solution. These data give isotope effects, k/sub H//k/sub D/ = 2.4 and 1.9 respectively, which show that these reactions occur by the normal, rate-determining carbon protonation, mechanism. The vinyl ether 6 is less reactive than its olefin analogue, bicyclo[3.3.1]non-1-ene (relative rate 1:1/1400), as may have been expected for a constrained bicyclic system such as this, where stabilization of the bridgehead carbocation intermediate by conjugation with oxygen is severely impaired. The vinyl sulfide 7, however, is even less reactive than the vinyl ether (relative rates 1:1/140); this is a remarkable result in view of the fact that conjugation between the sulfur atom and the cationic center is presumably also strongly inhibited. 1 figure, 3 tables

Detection of coronary artery disease - comparison of exercise stress radionuclide angiocardiography and thallium stress perfusion scanning

International Nuclear Information System (INIS)

Jengo, J.A.; Freeman, R.; Brizendine, M.; Mena, I.; St. Mary Medical Center, Long Beach, Calif.)

1980-01-01

Exercise thallium scanning and stress radionuclide angiography were compared in 16 normal subjects and 42 patients with more than 75% coronary arterial obstruction in studies using upright exercise on a bicycle ergometer. Studies at rest were subsequently obtained. Exercise thallium scans in the control group were normal in 15 and showed a defect in 1. Ejection fraction increased in all 16. During exercise, regional wall motion increased uniformly. In the group with coronary artery disease, thallium scanning revealed a new defect in the distribution of the involved arteries in 24 patients. In 15 who had a defect at rest, no new defect developed, but in 9 of the 15 new segmental wall motion defects were evident on radionuclide angiography. With exercise, ejection fraction decreased slightly. Regional wall motion abnormalities developed in the areas corresponding to thallium defects in all. Thallium scanning had a 93% and radionuclide angiography a 98% sensitivity value in detecting coronary artery disease. The respective specificity values were 94 and 100%. In patients with prior myocardial infarction who manifested new exercise abnormalities, 50% showed new thallium defects and 81% new wall motion defects