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Sample records for submaximal field exercise

  1. The effect of submaximal exercise on fibrinolysis.

    Science.gov (United States)

    Fras, Zlatko; Keber, Dusan; Chandler, Wayne L

    2004-04-01

    We studied the relationship between sustained submaximal exercise, increased tissue plasminogen activator (t-PA) levels and decreased hepatic clearance of t-PA. Six healthy male volunteers exercised for 35 min while receiving constant rate infusions of either saline or two different doses of recombinant t-PA for 90 min (40 min before, 35 min during and 15 min after exercise). Liver blood flow was estimated simultaneously by constant rate indocyanine green infusion. Since t-PA is cleared rapidly by the liver in direct proportion to liver blood flow, it was expected that a significant decrease in liver blood flow during sustained submaximal exercise would be associated with a proportional increase in plasma t-PA. During submaximal exercise with a saline (placebo) infusion, steady-state t-PA antigen increased from a resting baseline of 6.3 +/- 3.1 to 15.1 +/- 5.1 ng/ml; with a 20 microg/min t-PA infusion, t-PA antigen increased from 33 +/- 12 to 84 +/- 25 ng/ml during exercise; and with a 40 microg/min t-PA infusion, t-PA antigen increased from 77 +/- 38 to 166 +/- 42 ng/ml during exercise. During submaximal exercise, liver blood flow fell on average 71, 68 and 70%, respectively, during the three procedures, while calculated t-PA clearance decreased on average 59, 59 and 53%. t-PA concentration versus time curves, displayed in proportional units, were similar. The comparable relative increases in endogenous and exogenous t-PA with simultaneous proportional decreases in liver blood flow suggests that diminished hepatic t-PA clearance is the major cause of increased t-PA concentration and blood fibrinolytic activity enhancement during sustained submaximal exercise.

  2. Recruitment of single muscle fibers during submaximal cycling exercise

    NARCIS (Netherlands)

    Altenburg, T.M.; Degens, H.; van Mechelen, W.; Sargeant, A.J.; de Haan, A.

    2007-01-01

    In literature, an inconsistency exists in the submaximal exercise intensity at which type II fibers are activated. In the present study, the recruitment of type I and II fibers was investigated from the very beginning and throughout a 45-min cycle exercise at 75% of the maximal oxygen uptake, which

  3. Reliability of oscillometric central blood pressure responses to submaximal exercise.

    Science.gov (United States)

    Lim, Weijie; Faulkner, James; Lambrick, Danielle; Stoner, Lee

    2016-06-01

    Central blood pressure responses to exercise may provide clinicians with a superior diagnostic and prognostic tool. However, to be of value in a clinical setting these assessments must be simple to conduct and reliable. Using oscillometric pulse wave analysis (PWA), determine the upper limit for between-day reliability of central SBP (cSBP) and central pressure augmentation (AIx) responses to three progressive stages of submaximal exercise in a cohort of young, healthy participants. Fifteen healthy males [25.8 years (SD 5.7), 23.9 kg/m (SD 2.5)] were tested on three different mornings in a fasted state, separated by a maximum of 14 days. Central hemodynamic variables were assessed on the left upper arm. Participants underwent three progressive stages of submaximal cycling at 50 W (low), 100 W (moderate) and 150 W (moderate-hard). During low and moderate-intensity exercise the intra-class correlation coefficient (ICC) values for cSBP (0.79-0.80) and AIx (0.81-0.85) indicated excellent reliability (ICC > 0.75). For the moderate-hard intensity AIx could not be computed, and the ICC for cSBP was adequate (0.72). Findings from this study suggest that, at least in a young, healthy cohort, oscillometric PWA can be used to reliably assess central blood pressure measurements during exercise, up to a moderate intensity. Although further work is required to verify these findings in clinical cohorts, these measurements may potentially provide clinicians with a practical option for obtaining important hemodynamic information beyond that provided by resting peripheral blood pressure.

  4. Acclimatization improves submaximal exercise economy at 5533 m.

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    Latshang, T D; Turk, A J; Hess, T; Schoch, O D; Bosch, M M; Barthelmes, D; Merz, T M; Hefti, U; Hefti, J Pichler; Maggiorini, M; Bloch, K E

    2013-08-01

    We tested whether the better subjective exercise tolerance perceived by mountaineers after altitude acclimatization relates to enhanced exercise economy. Thirty-two mountaineers performed progressive bicycle exercise to exhaustion at 490 m and twice at 5533 m (days 6-7 and day 11), respectively, during an expedition to Mt. Muztagh Ata. Maximal work rate (W(max)) decreased from mean ± SD 356 ± 73 watts at 490 m to 191 ± 49 watts and 193 ± 45 watts at 5533 m, days 6-7 and day 11, respectively; corresponding maximal oxygen uptakes (VO2max ) were 50.7 ± 9.5, 26.3 ± 5.6, 24.7 ± 7.0 mL/min/kg (P = 0.0001 5533 m vs 490 m). On days 6-7 (5533 m), VO(2) at 75% W(max) (152 ± 37 watts) was 1.75 ± 0.45 L/min, oxygen saturation 68 ± 8%. On day 11 (5533 m), at the same submaximal work rate, VO(2) was lower (1.61 ± 0.47 L/min, P scale 50 ± 15 vs 57 ± 20, P = 0.006) and reduced symptoms of acute mountain sickness. We conclude that the better performance and subjective exercise tolerance after acclimatization were related to regression of acute mountain sickness and improved submaximal exercise economy because of lower metabolic demands for non-external work-performing functions. © 2011 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Cardiac Autonomic Function during Submaximal Treadmill Exercise in Adults with Down Syndrome

    Science.gov (United States)

    Mendonca, Goncalo V.; Pereira, Fernando D.; Fernhall, Bo

    2011-01-01

    This study determined whether the cardiac autonomic function of adults with Down syndrome (DS) differs from that of nondisabled persons during submaximal dynamic exercise. Thirteen participants with DS and 12 nondisabled individuals performed maximal and submaximal treadmill tests with metabolic and heart rate (HR) measurements. Spectral analysis…

  6. Effect of the Canadian Air Force training programme on a submaximal exercise test.

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    Kappagoda, C T; Linden, R J; Newell, J P

    1979-07-01

    Validation of the submaximal heart rate/oxygen consumption relationship as an index of 'cardiorespiratory fitness' requires the demonstration of systematic alterations in this relationship concomitant with interventions designed to alter physical fitness. To fulfil those criteria a longitudinal training/de-training study was undertaken. Previously sedentary adult subjects undertook the Canadian Airforce 5BX-XBX exercise programme. Submaximal exercise tests were performed before and after training, and following several weeks cessation of training. A regression line of submaximal heart rate on submaximal oxygen consumption was calculated from the data of each submaximal exercise test. Alterations in the regression lines were examined for each subject individually by testing statistically for difference in slope and elevation between any pair of lines. Subjects who undertook the training/de-training study demonstrated significant systematic alterations in the elevation of the regression lines concomitant with periods of training and de-training. The reproducibility of the submaximal heart rate/oxygen consumption relationship was examined in two additional groups of subjects. Group A repeated a submaximal test on 3 or 4 successive days; Group B were tested before and after 16 weeks of normal activity. Subjects in Group A demonstrated non significant, random alterations in the regression lines on repeated testing and subjects in Group B demonstrated random, though on occasion significant, alterations in the regression lines. The elevation of the submaximal heart rate/oxygen consumption relationship is therefore a valid index for detecting sequential changes in 'cardiorespiratory fitness' in individual subjects.

  7. Cardiovascular responses during a submaximal exercise test in patients with Parkinson's disease.

    Science.gov (United States)

    Speelman, Arlène D; Groothuis, Jan T; van Nimwegen, Marlies; van der Scheer, Ellis S; Borm, George F; Bloem, Bastiaan R; Hopman, Maria T E; Munneke, Marten

    2012-01-01

    Patients with Parkinson's disease (PD) are physically less active than controls, and autonomic dysfunction may contribute to this sedentary lifestyle. Specifically, an altered cardiovascular response to physical effort may restrict physical activities. To assess the cardiovascular responses to a submaximal exercise test in PD patients and controls, 546 sedentary PD patients and 29 sedentary healthy controls performed the Åstrand-Rhyming submaximal cycle exercise test. Average heart rate was used to estimate maximal oxygen consumption (VO2max). Variables that may affect submaximal activity in PD patients, including disease severity, fatigue, and level of physical activity in daily life, were recorded. Fewer PD patients (46%) completed the submaximal exercise test successfully than the controls (86%). The estimated VO2max of patients with a successful test was 34% lower than the controls (p physical activities further.

  8. THE INFLUENCE OF OBESITY AND AMBIENT TEMPERATURE ON PHYSIOLOGICAL AND OXIDATIVE RESPONSES TO SUBMAXIMAL EXERCISE

    OpenAIRE

    Ahn, N.; Kim, K.

    2014-01-01

    This study investigated the effects of obesity and ambient temperature on physiological responses and markers of oxidative stress to submaximal exercise in obese and lean people. Sixteen healthy males were divided into an obese group (n=8, %fat: 27.00±3.00%) and a lean group (n=8, %fat: 13.85±2.45%). Study variables were measured during a 60 min submaximal exercise test at 60% VO2max in a neutral (21±1°C) and a cold (4±1°C) environment. Heart rate, blood lactate, rectal temperature, serum lev...

  9. Variation in heart rate during submaximal exercise: Implications for monitoring training : Implications for monitoring training

    NARCIS (Netherlands)

    Lamberts, R.P.; Lemmink, K.A.P.M.; Durandt, J.J.; Lambert, M.I.

    2004-01-01

    A change in heart rate at a controlled submaximal exercise intensity is used as a marker of training status. However, the standard error of measurement has not been studied systematically, and therefore a change in heart rate, which can be considered relevant, has not been determined. Forty-four

  10. Systolic blood pressure reactivity during submaximal exercise and acute psychological stress in youth

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    Background: Studies in youth show an association between systolic blood-pressure (SBP) reactivity to acute psychological stress and carotid artery intima-media thickness (CIMT). However, it has not yet been determined whether SBP reactivity during submaximal exercise is also associated with CIMT i...

  11. THE INFLUENCE OF OBESITY AND AMBIENT TEMPERATURE ON PHYSIOLOGICAL AND OXIDATIVE RESPONSES TO SUBMAXIMAL EXERCISE

    Directory of Open Access Journals (Sweden)

    N. Ahn

    2014-07-01

    Full Text Available This study investigated the effects of obesity and ambient temperature on physiological responses and markers of oxidative stress to submaximal exercise in obese and lean people. Sixteen healthy males were divided into an obese group (n=8, %fat: 27.00±3.00% and a lean group (n=8, %fat: 13.85±2.45%. Study variables were measured during a 60 min submaximal exercise test at 60% VO2max in a neutral (21±1°C and a cold (4±1°C environment. Heart rate, blood lactate, rectal temperature, serum levels of malondialdehyde (MDA and superoxide dismutase (SOD were measured at rest, during exercise and in recovery. Heart rate of both groups was significantly lower (P<0.05 in the cold than the warm environment, but there were no significant differences between the two groups. Serum SOD activity increased to a significantly greater extent (P<0.05 in the cold than the neutral environment, and remained elevated for longer during exercise in the obese group than the lean group. Serum MDA level during submaximal exercise was not significantly different between conditions or groups. Cold stress in exercise may challenge antioxidant defence mechanisms in obese subjects, but lipid peroxidation remains unchanged.

  12. Prognostic value of treadmill stress echocardiography at extremes of exercise performance: submaximal high exercise capacity ≥ 10 metabolic equivalents.

    Science.gov (United States)

    Yao, Siu-Sun; Agarwal, Vikram; Chaudhry, Farooq A

    2014-03-01

    Submaximal stress testing or achieving High exercise capacity (≥ 10 metabolic equivalents, METS) is a predictor of favorable prognosis. The purpose of this study was to evaluate the prognostic value of submaximal or high exercise capacity stress echocardiography. We evaluated 1781 patients (55 ± 13 years; 59% male) undergoing treadmill stress echocardiography divided into 811 patients with submaximal (high exercise capacity (≥ 10 METS). Resting left ventricular ejection fraction and regional wall motion were assessed. The left ventricle was divided into 16 segments and scored on 5-point scale of wall motion. Abnormal stress echocardiography was defined as stress-induced ischemia (wall-motion score of ≥ 1 grade). Follow-up (3.3 ± 1.5 years) for nonfatal myocardial infarction (MI) (n = 40) and cardiac death (n = 52) were obtained. By univariate analysis, echocardiographic variables of ejection fraction, peak wall-motion score index (WMSI) and number of new ischemic wall-motion abnormalities were significant predictors of cardiac events. Cumulative survival was significantly worse in patients with abnormal (ischemic) versus normal (nonischemic) stress echocardiography in submaximal (4.4%/year vs. 1.3%/year, P high exercise capacity (1.5%/year vs. 0.2%/year, P high exercise capacity studies. © 2013, Wiley Periodicals, Inc.

  13. The Usefulness of Submaximal Exercise Gas Exchange in Pulmonary Arterial Hypertension: A Case Series

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    Paul R. Woods

    2010-04-01

    Full Text Available Introduction Submaximal exercise gas exchange may be a useful tool to track responses to therapy in pulmonary arterial hypertension (PAH patients. Methods Three patients diagnosed with idiopathic PAH, on differing therapies, were included. Standard clinical tests (echocardiography; 6 minute walk were performed pre and 3-5 months after treatment. Gas exchange was measured during 3 minutes of step exercise at both time points. Results Gas exchange variables, end tidal CO 2 (P ET CO 2 and the ratio of ventilation to CO 2 production (V E /VCO 2 , during submaximal exercise were able to track patient responses to therapy over a 3-5 month period. Two patients demonstrated positive improvements, with an increased P ET CO 2 and decreased V E /VCO 2 during light exercise, in response to an altered therapeutic regime. The third patient had a worsening of gas exchange (decreased P ET CO 2 and increased V E /VCO 2 following no changes in the medical regime from the baseline visit. Conclusion Gas exchange variables measured during light submaximal exercise, such as P ET CO 2 and V E /VCO 2 , may be able to better detect small changes in functional status following treatment and could, therefore, be a useful tool to track disease severity in PAH patients. Further study is required to determine the clinical usefulness of these gas exchange variables.

  14. Iron Status in Chronic Heart Failure: Impact on Symptoms, Functional Class and Submaximal Exercise Capacity.

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    Enjuanes, Cristina; Bruguera, Jordi; Grau, María; Cladellas, Mercé; Gonzalez, Gina; Meroño, Oona; Moliner-Borja, Pedro; Verdú, José M; Farré, Nuria; Comín-Colet, Josep

    2016-03-01

    To evaluate the effect of iron deficiency and anemia on submaximal exercise capacity in patients with chronic heart failure. We undertook a single-center cross-sectional study in a group of stable patients with chronic heart failure. At recruitment, patients provided baseline information and completed a 6-minute walk test to evaluate submaximal exercise capacity and exercise-induced symptoms. At the same time, blood samples were taken for serological evaluation. Iron deficiency was defined as ferritin < 100 ng/mL or transferrin saturation < 20% when ferritin is < 800 ng/mL. Additional markers of iron status were also measured. A total of 538 heart failure patients were eligible for inclusion, with an average age of 71 years and 33% were in New York Heart Association class III/IV. The mean distance walked in the test was 285 ± 101 meters among those with impaired iron status, vs 322 ± 113 meters (P=.002). Symptoms during the test were more frequent in iron deficiency patients (35% vs 27%; P=.028) and the most common symptom reported was fatigue. Multivariate logistic regression analyses showed that increased levels of soluble transferrin receptor indicating abnormal iron status were independently associated with advanced New York Heart Association class (P < .05). Multivariable analysis using generalized additive models, soluble transferrin receptor and ferritin index, both biomarkers measuring iron status, showed a significant, independent and linear association with submaximal exercise capacity (P=.03 for both). In contrast, hemoglobin levels were not significantly associated with 6-minute walk test distance in the multivariable analysis. In patients with chronic heart failure, iron deficiency but not anemia was associated with impaired submaximal exercise capacity and symptomatic functional limitation. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  15. Monitoring Training Progress During Exercise Training in Cancer Survivors : A Submaximal Exercise Test as an Alternative for a Maximal Exercise Test?

    NARCIS (Netherlands)

    May, Anne M.; van Weert, Ellen; Korstjens, Irene; Hoekstra-Weebers, Josette E.; van der Schans, Cees P.; Zonderland, Maria L.; Mesters, Ilse; van den Borne, Bart; Ros, Wynand J.

    May AM, van Weert E, Korstjens 1, Hoekstra-Weebers JE, van der Schans CP, Zonderland ML, Mesters 1, van den Borne B, Ros WJ. Monitoring training progress during exercise training in cancer survivors: a submaximal exercise test as an alternative for a maximal exercise test? Arch Phys Med Rehabil

  16. Effects of submaximal exercise and noise exposure on hearing loss.

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    Alessio, H M; Hutchinson, K M

    1991-12-01

    A recent Scandinavian study reported that persons cycling at moderate intensity for 10 min suffered hearing loss when the exercise was accompanied by noise. The noise consisted of a 1/3 octave band-filtered noise with a 2000 Hz center frequency at 104 dB SPL. In the present study, adults cycled at 50 rev.min-1 against a force that elicited an oxygen cost equal to 70% of VO2max--an intensity frequently recommended in exercise prescriptions--with and without noise administered via headphones. Repeated measures ANOVA with three factors revealed that although a temporary hearing loss occurred following exercise-and-noise, a similar and slightly greater hearing loss occurred following noise-only. Hearing sensitivity was not significantly altered by exercise-only (p greater than .05). In general, hearing loss values were greatest between 3000 and 4000 Hz. In conclusion, temporary hearing loss was driven by noise exposure, not exercise. However, persons who choose to exercise with personal headphones or in a noisy environment should be aware of potential premature hearing loss.

  17. Altitude Acclimatization Attentuates Plasma Ammonia during Submaximal Exercise,

    Science.gov (United States)

    1986-05-01

    citrulline synthesis in rat liver mitochondria : The effect of ammonia and energy. Int. J. Biochem. 10:235-239, 1979. 14 9. Buono, M.J., T.R. Clancy, and J.R...Mole, P.A., L.B. Oscal, and J.0. Holloszy. Adaptation of muscle to exercise. Increase in levels of palmityl CoA synthetase, carnitine

  18. Haemodynamic changes induced by submaximal exercise before a dive and its consequences on bubble formation

    Science.gov (United States)

    Blatteau, Jean‐Eric; Boussuges, Alain; Gempp, Emmanuel; Pontier, Jean‐Michel; Castagna, Olivier; Robinet, Claude; Galland, Francois‐Michel; Bourdon, Lionel

    2007-01-01

    Objectives To evaluate the effects of a submaximal exercise performed 2 h before a simulated dive on bubble formation and to observe the haemodynamic changes and their influence on bubble formation. Participants and methods 16 trained divers were compressed in a hyperbaric chamber to 400 kPa for 30 min and decompressed at a rate of 100 kPa/min with a 9 min stop at 130 kPa (French Navy MN90 procedure). Each diver performed two dives 3 days apart, one without exercise and one with exercise before the dive. All participants performed a 40 min constant‐load submaximal and calibrated exercise, which consisted of outdoor running 2 h before the dive. Circulating bubbles were detected with a precordial Doppler at 30, 60 and 90 min after surfacing. Haemodynamic changes were evaluated with Doppler echocardiography. Results A single bout of strenuous exercise 2 h before a simulated dive significantly reduced circulating bubbles. Post‐exercise hypotension (PEH) was observed after exercise with reductions in diastolic and mean blood pressure (DBP and MBP), but total peripheral resistance was unchanged. Stroke volume was reduced, whereas cardiac output was unchanged. Simulated diving caused a similar reduction in cardiac output independent of pre‐dive exercise, suggesting that pre‐dive exercise only changed DBP and MBP caused by reduced stroke volume. Conclusion A single bout of strenuous exercise 2 h before a dive significantly reduced the number of bubbles in the right heart of divers and protected them from decompression sickness. Declining stroke volume and moderate dehydration induced by a pre‐dive exercise might influence inert gas load and bubble formation. PMID:17138641

  19. Variation in heart rate during submaximal exercise: implications for monitoring training.

    Science.gov (United States)

    Lamberts, Robert P; Lemmink, Koen A P M; Durandt, Justin J; Lambert, Michael I

    2004-08-01

    A change in heart rate at a controlled submaximal exercise intensity is used as a marker of training status. However, the standard error of measurement has not been studied systematically, and therefore a change in heart rate, which can be considered relevant, has not been determined. Forty-four subjects (26.5 +/- 5.4 years; mean +/- standard deviation) participated in a submaximal running test at the same time of day for 5 consecutive days. Heart rates were determined during each of the 4 exercise intensities (2 minutes each) of increasing intensity and during the 1-minute recovery period after each stage. The repeatability of the heart rate on a day-to-day basis during the stages and recovery periods were high (intraclass correlation coefficient: 95% confidence interval R = 0.94- 0.99). The lowest variation in heart rate occurred in the fourth stage ( approximately 90% maximum heart rate) with heart rate varying 5 +/- 2 b.min(-1) (95% confidence interval for coefficient of variation = 1.1-1.4%). In conclusion, the standard error of measurement of submaximal heart rate is 1.1-1.4%. This magnitude of measurement error needs to be considered when heart rate is used as a marker of training status.

  20. [Submaximal exercise capacity and quality of life in exclusive water-pipe smokers].

    Science.gov (United States)

    Ben Saad, H; Babba, M; Boukamcha, R; Latiri, I; Knani, J; Slama, R; Bougmiza, I; Zbidi, A; Tabka, Z

    2010-05-01

    It is well known that oxidative stress is increased significantly by regular water-pipe smoking (WPS). This could lead to muscle dysfunction and thus to impairments of exercise and quality of life (QOL). Considering the impressive number of WP smokers, we intend to investigate the potential effect of WPS on submaximal exercise capacity and QOL. (1). To evaluate the submaximal exercise capacity by the 6-minutes walking test (6-MWT). (2). To compare the deficiency, incapacity and QOL data of exclusive WPS with those of two control groups (never smokers and exclusive cigarette smokers). (3). To determine the factors influencing the 6-minutes walk distance (6-MWD) of WPS subjects. A multicentre study including 180 exclusive WPS [> or =5 WP-year] men aged > or =40 years. Cigar or cigarette smoking, contraindications to the 6-MWT or cortico-steroid therapy will be exclusion criteria. QOL evaluation, spirometry, electrocardiogram and two 6-MWT will be performed. Signs of exercise impairment will be: 6-MWD or =5/10, haemoglobin saturation fall > or =5 points. Data from WPS subjects will be compared with those from 90 never smoking subjects and 90 exclusives cigarettes smokers. (1). WPS will affect significantly the submaximal exercise capacity. (2). Resting spirometric, 6-MWT and QOL data of exclusive WPS subjects will be significantly reduced compared to never smoking subjects. (3). The 6-MWD's of exclusive WPS subjects will be significantly influenced by cumulative WP consumption, by resting spirometric data, by obesity and by physical activity score. Copyright 2010 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  1. Cognitive Performance Enhancement Induced by Caffeine, Carbohydrate and Guarana Mouth Rinsing during Submaximal Exercise

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    Laura Pomportes

    2017-06-01

    Full Text Available The aim of this study was to investigate the influence of serial mouth rinsing (MR with nutritional supplements on cognitive performance (i.e., cognitive control and time perception during a 40-min submaximal exercise. Twenty-four participants completed 4 counterbalanced experimental sessions, during which they performed MR with either placebo (PL, carbohydrate (CHO: 1.6 g/25 mL, guarana complex (GUAc: 0.4 g/25 mL or caffeine (CAF: 67 mg/25 mL before and twice during exercise. The present study provided some important new insights regarding the specific changes in cognitive performance induced by nutritional supplements. The main results were: (1 CHO, CAF and GUA MR likely led participants to improve temporal performance; (2 CAF MR likely improved cognitive control; and (3 CHO MR led to a likely decrease in subjective perception of effort at the end of the exercise compared to PL, GUA and CAF. Moreover, results have shown that performing 40-min submaximal exercise enhances information processing in terms of both speed and accuracy, improves temporal performance and does not alter cognitive control. The present study opens up new perspectives regarding the use of MR to optimize cognitive performance during physical exercise.

  2. Test retest reliability and minimal detectable change of a novel submaximal graded exercise test in the measurement of graded exercise test duration.

    Science.gov (United States)

    Taylor, James D; Bandy, William D; Whittemore, Joe D

    2011-05-01

    Measurement of graded exercise test duration is clinically important and can be assessed by maximal graded exercise testing. Yet, limitations of maximal graded exercise testing exist. An alternative to maximal graded exercise testing is submaximal graded exercise testing. However, no studies have investigated the reliability of a submaximal graded exercise test in the measurement of graded exercise test duration. The purpose of this study was to determine the test-retest reliability and minimal detectable change (MDC) of a novel submaximal graded exercise test in the measurement of graded exercise test duration. Fifteen people (4 men, 11 women) with a mean age of 26.20 years (SD = 9.04) participated in this study. A novel submaximal graded exercise test was used to measure graded exercise test duration for each participant. Endpoints of the test were either 85% of age-predicted maximum heart rate or voluntarily stopping the test, whichever endpoint occurred first. Heart rate and graded exercise test duration were constantly measured throughout the test. Graded exercise test duration was defined as the total duration (minutes) of the test. For all participants, the submaximal graded exercise test was conducted at baseline and 48-72 hours thereafter. The intraclass correlation coefficient for the test-retest reliability of the test in determining graded exercise test duration was 0.94 (95% CI = 0.83-0.98). The MDC of the test in the measurement of graded exercise test duration was 0.86 minutes. The results suggest that clinicians can use this novel submaximal graded exercise test to reliably measure graded exercise test duration with a measurement error, as expressed by the MDC, of 0.86 minutes.

  3. Evaluation of Exercise Response in a Young, High Risk Population: Submaximal Invasive Cardiopulmonary Exercise Testing (ICPET) in Active Duty Soldiers

    Science.gov (United States)

    2017-03-17

    Submaximal Invasive Cardiopulmonary Exercise Testing iCPET in AD Soldiers presented at/published to American College of Cardiology’s 661h Annual...disclaimer statement for research involving animals . as required by AFMAN 40-401 IP : " The experiments reported herein were conducted according to the...principles set forth in the National Institute of Health Publication No. 80-23, Guide for the Care and Use of Laboratory Animals and the Animal

  4. The physiology of submaximal exercise: The steady state concept.

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    Ferretti, Guido; Fagoni, Nazzareno; Taboni, Anna; Bruseghini, Paolo; Vinetti, Giovanni

    2017-12-01

    The steady state concept implies that the oxygen flow is invariant and equal at each level along the respiratory system. The same is the case with the carbon dioxide flow. This condition has several physiological consequences, which are analysed. First, we briefly discuss the mechanical efficiency of exercise and the energy cost of human locomotion, as well as the roles played by aerodynamic work and frictional work. Then we analyse the equations describing the oxygen flow in lungs and in blood, the effects of ventilation and of the ventilation - perfusion inequality, and the interaction between diffusion and perfusion in the lungs. The cardiovascular responses sustaining gas flow increase in blood are finally presented. An equation linking ventilation, circulation and metabolism is developed, on the hypothesis of constant oxygen flow in mixed venous blood. This equation tells that, if the pulmonary respiratory quotient stays invariant, any increase in metabolic rate is matched by a proportional increase in ventilation, but by a less than proportional increase in cardiac output. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. The Impact of a Submaximal Level of Exercise on Balance Performance in Older Persons

    Science.gov (United States)

    2014-01-01

    Objective. The purpose of this study was to determine the impact of a submaximal level of exercise on balance performance under a variety of conditions. Material and Method. Thirteen community-dwelling older persons with intact foot sensation (age = 66.69 ± 8.17 years, BMI = 24.65 ± 4.08 kg/m2, female, n = 6) volunteered to participate. Subjects' balance performances were measured using the Modified Clinical Test of Sensory Integration of Balance (mCTSIB) at baseline and after test, under four conditions of stance: (1) eyes-opened firm-surface (EOF), (2) eyes-closed firm-surface (ECF), (3) eyes-opened soft-surface (EOS), and (4) eyes-closed soft-surface (ECS). The 6-minute walk test (6MWT) protocol was used to induce the submaximal level of exercise. Data was analyzed using the Wilcoxon Signed-Rank Test. Results. Balance changes during EOF (z = 0.00, P = 1.00) and ECF (z = −1.342, P = 0.180) were not significant. However, balance changes during EOS (z = −2.314, P = 0.021) and ECS (z = −3.089, P = 0.02) were significantly dropped after the 6MWT. Conclusion. A submaximal level of exercise may influence sensory integration that in turn affects balance performance, particularly on an unstable surface. Rehabilitation should focus on designing intervention that may improve sensory integration among older individuals with balance deterioration in order to encourage functional activities. PMID:25383386

  6. Hypotension and heart rate variability after resistance exercise performed maximal and submaximal order

    Directory of Open Access Journals (Sweden)

    Victor Gonçalves Corrêa Neto

    2017-06-01

    Full Text Available The aim of the study was verified the blood pressure responses and the cardiac autonomic modulation after the strength exercise in two different conditions (maximal and submaximal. The subjects were divided in three groups, such as: maximal repetitions (age: 20.5 ± 0.6 years, weight: 63.7 ± 14.8, height: 1.7 ± 0.1, body mass index: 22.8 ± 4.5 Kilogram per square meter (kg/m², submaximal repetitions (age: 25 ± 4.1 years, weight: 69.1 ± 12.8, height: 1.8 ± 0.1, body mass index: 22.2 ± 1.7 (kg/m²  and a control group (age: 23.7 ± 3.8 years, weight: 64.2 ± 15, height: 1.7 ± 0.1, body mass index: 21.8 ± 1.9 (kg/m². The blood pressure and the Heart Rate R-R intervals were measured before and during one hour after the session, with 10-minutes intervals length between measurements. The analyze of variance did not showed significant differences between experimental protocols to blood pressure (p > 0.05. However, the effect size was able to show that the most intense training caused a reduction in systolic blood pressure at times. Regarding cardiac autonomic response, the group that exercised the submaximal form exhibited a significant increase in LF / HF (p = 0.022 when 20 minutes’ post-exercise. There was a not significant difference in cardiac autonomic modulation between protocols. The high intensity protocol has caused blood pressure reductions in more moments and it was over safer in relation to cardiac autonomic modulation, since it did not cause increased sympathetic activity during recovery.

  7. Comparison of the YMCA and a Custom Submaximal Exercise Test for Determining VO2max.

    Science.gov (United States)

    Jamnick, Nicholas A; By, Savanny; Pettitt, Cherie D; Pettitt, Robert W

    2016-02-01

    The maximal oxygen uptake (VO2max) is deemed the highest predictor for all-cause mortality, and therefore, an ability to assess VO2max is important. The YMCA submaximal test is one of the most widely used tests to estimate VO2max; however, it has questionable validity. We validated a customized submaximal test that accounts for the nonlinear rise in VO2 relative to power output and compared its accuracy against the YMCA protocol. Fifty-six men and women performed a graded exercise test with a subsequent exhaustive, square wave bout for the verification of "true" VO2max. In counterbalanced order, subjects then completed the YMCA test and our new Mankato submaximal exercise test (MSET). The MSET consisted of a 3-min stage estimated at 35% VO2max and a second 3-min stage estimated at either 65% or 70% VO2max, where VO2max was estimated with a regression equation using sex, body mass index, age, and self-reported PA-R. VO2 values from the graded exercise test and square wave verification bout did not differ with the highest value used to identify "true" VO2max (45.1 ± 8.89 mL · kg(-1) · min(-1)). The MSET (43.6 ± 8.6 mL · kg(-1) · min(-1)) did not differ from "true" VO2max, whereas the YMCA test (41.1 ± 9.6 mL · kg(-1) · min(-1)) yielded an underestimation (P = 0.002). The MSET was moderately correlated with "true" VO2max (ICC = 0.73, CV of 11.3%). The YMCA test was poorly correlated with "true" VO2max (ICC = 0.29, CV of 15.1%). To our knowledge, this is the first study to examine submaximal exercise protocols versus a verified VO2max protocol. The MSET yielded better estimates of VO2max because of the protocol including a stage exceeding gas exchange threshold.

  8. VO2@RER1.0: a novel submaximal cardiopulmonary exercise index.

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    Chin, Clifford; Kazmucha, Jeffrey; Kim, Nancy; Suryani, Reny; Olson, Inger

    2010-01-01

    Maximal oxygen consumption (VO2max) is the "gold standard" by which to assess functional capacity; however, it is effort dependent. VO2@RER1.0 is defined when VO2 = VCO2. Between December 22, 1997 and November 9, 2004, 305 pediatric subjects underwent cycle ergometer cardiopulmonary exercise testing, exercised to exhaustion, and reached a peak respiratory exchange ratio > or = 1.10. Group 1 subjects achieved a peak VO2 > or = 80% of predicted VO2max; group 2 subjects achieved a peak VO2 subjects achieved a peak VO2 between 61 and 79% of predicted VO2max. Linear regression analysis was performed for VO2@RER1.0 as a function of predicted VO2 for group 1 subjects. A -2 SD regression line and equation was created. VO2@RER1.0 data from groups 2 and 3 were plotted onto the normative graph. Contingency table and relative-risk analysis showed that an abnormal VO2@RER1.0 predicted an abnormal peak VO2(positive-predictive value 83%, negative-predictive value 85%, sensitivity 84%, and specificity 84%). VO2@RER1.0 is a highly sensitive, specific, and predictive submaximal index of functional capacity. This submaximal index is easy to identify without subjectivity. This index may aid in the evaluation of subjects who cannot exercise to maximal parameters.

  9. Brief note about plasma catecholamines kinetics and submaximal exercise in untrained standardbreds

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    Paolo Baragli

    2010-03-01

    Full Text Available Four untrained standardbred horses performed a standardized exercise test on the treadmill and an automated blood collection system programmed to obtain blood samples every 15 s was used for blood collection in order to evaluate the kinetics of adrenaline and noradrenaline. The highest average values obtained for adrenaline and noradrenaline were 15.0 ± 3.0 and 15.8 ± 2.8 nmol/l respectively, with exponential accumulation of adrenaline (r = 0.977 and noradrenaline (r = 0.976 during the test. Analysis of the correlation between noradrenaline and adrenaline for each phase of the test shows that correlation coefficient decreases as the intensity of exercise increases (from r = 0.909 to r = 0.788. This suggests that during submaximal exercise, the process for release, distribution and clearance of adrenaline into blood circulation differs from that of noradrenaline.

  10. Blunted Maximal and Submaximal Responses to Cardiopulmonary Exercise Tests in Patients With Parkinson Disease.

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    Kanegusuku, Hélcio; Silva-Batista, Carla; Peçanha, Tiago; Nieuwboer, Alice; Silva, Natan D; Costa, Luiz A; de Mello, Marco T; Piemonte, Maria E; Ugrinowitsch, Carlos; Forjaz, Cláudia L

    2016-05-01

    To investigate submaximal and maximal responses during maximal cardiopulmonary exercise tests in subjects with Parkinson disease (PD). Cross-sectional. A PD association. A sample (N=68) of subjects with PD (n=48; mean age, 66±8y; modified Hoehn and Yahr stage between 2 and 3; "on" state of medication) and age-matched controls without PD (n=20; mean age, 64±9y). Maximal cardiopulmonary exercise test on a cycle ergometer. Oxygen uptake (V˙o2), systolic blood pressure (SBP), and heart rate assessed at rest, submaximal intensities (ie, anaerobic threshold [AT] and respiratory compensation point), and maximal intensity (peak exercise). Compared with control subjects, subjects with PD had lower V˙o2, heart rate, and SBP at respiratory compensation point and peak exercise (V˙o2: 14.6±3.6mL⋅kg⋅min vs 17.9±5.5mL⋅kg⋅min and 17.7±4.8mL⋅kg⋅min vs 21.5±6.6mL⋅kg⋅min; heart rate: 119±17beats/min vs 139±12beats/min and 132±20beats/min vs 158±13beats/min; SBP: 151±17mmHg vs 172±20mmHg and 166±21mmHg vs 187±24mmHg; P≤.05). They also had lower heart rate at AT (102±14beats/min vs 110±13beats/min; P≤.05), whereas V˙o2 and SBP at this intensity were similar to those of control subjects. Subjects with PD demonstrated blunted metabolic and cardiovascular responses to submaximal and maximal exercise tests, especially at intensities above AT, which are in line with autonomic disturbances present in patients with PD. Future studies need to determine how this affects performance, participation, and responses of these patients to exercise training at different intensities. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  11. Is the ventilatory threshold coincident with maximal fat oxidation during submaximal exercise in women?

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    Astorino, T A

    2000-09-01

    The purpose of this study was to detect the fraction of peak oxygen consumption (VO2peak) that elicits maximal rates of fat oxidation during submaximal treadmill exercise. It was hypothesized that this point would appear at a work rate just below the ventilatory threshold. subjects completed a protocol requiring them to exercise for 15 min on a treadmill at six different workloads, 25, 40, 55, 65, 75, and 85% VO2peak, over two separate visits. nine healthy, moderately-trained eumenorrheic females (age = 28.8+/-5.99 yrs, VO2peak = 47.20 +/-2.57 ml x kg(-1) x min(-1)) volunteered for the study. a one-way ANOVA with repeated measures was used to test for differences across exercise intensities in the metabolic variables (i.e. substrate oxidation, blood lactate concentration ([La-]), RER, and the contribution of fat to total energy expenditure). Following significant F ratios, post-hoc tests were used to detect differences between the means for various exercise intensities. Exercise at 75% VO2peak elicited the greatest rate of fat oxidation (4.75+/-0.49 kcal x min(-1)), and this intensity was coincident with the ventilatory threshold (76+/-7.41% VO2peak). Moreover, a significant difference (t(8) = -3.98, ppopulation has application in exercise prescription and refutes the belief that low-intensity exercise is preferred for fat metabolism.

  12. Reliability of heart rate variability threshold and parasympathetic reactivation after a submaximal exercise test

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    Carlos Janssen Gomes da Cruz

    Full Text Available Abstract The objective of this study was to evaluate reproducibility of heart rate variability threshold (HRVT and parasympathetic reactivation in physically active men (n= 16, 24.3 ± 5.1 years. During the test, HRVT was assessed by SD1 and r-MSSD dynamics. Immediately after exercise, r-MSSD was analyzed in segments of 60 seconds for a period of five minutes. High absolute and relatively reproducible analysis of HRVT were observed, as assessed by SD1 and r-MSSD dynamics (ICC = 0.92, CV = 10.8, SEM = 5.8. During the recovery phase, a moderate to high reproducibility was observed for r-MSSD from the first to the fifth minute (ICC = 0.69-0.95, CV = 7.5-14.2, SEM = 0.07-1.35. We conclude that HRVT and r-MSSD analysis after a submaximal stress test are highly reproducible measures that might be used to assess the acute and chronic effects of exercise training on cardiac autonomic modulation during and/or after a submaximal stress test.

  13. The Effects of Caffeine Supplementation on Physiological Responses to Submaximal Exercise in Endurance-Trained Men.

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    Glaister, Mark; Williams, Benjamin Henley; Muniz-Pumares, Daniel; Balsalobre-Fernández, Carlos; Foley, Paul

    2016-01-01

    The aim of this study was to evaluate the effects of caffeine on physiological responses to submaximal exercise, with a focus on blood lactate concentration ([BLa]). Using a randomised, single-blind, crossover design; 16 endurance-trained, male cyclists (age: 38 ± 8 years; height: 1.80 ± 0.05 m; body mass: 76.6 ± 7.8 kg; [Formula: see text]: 4.3 ± 0.6 L∙min-1) completed four trials on an electromagnetically-braked cycle ergometer. Each trial consisted of a six-stage incremental test (3 minute stages) followed by 30 minutes of passive recovery. One hour before trials 2-4, participants ingested a capsule containing 5 mg∙kg-1 of either caffeine or placebo (maltodextrin). Trials 2 and 3 were designed to evaluate the effects of caffeine on various physiological responses during exercise and recovery. In contrast, Trial 4 was designed to evaluate the effects of caffeine on [BLa] during passive recovery from an end-exercise concentration of 4 mmol∙L-1. Relative to placebo, caffeine increased [BLa] during exercise, independent of exercise intensity (mean difference: 0.33 ± 0.41 mmol∙L-1; 95% likely range: 0.11 to 0.55 mmol∙L-1), but did not affect the time-course of [BLa] during recovery (p = 0.604). Caffeine reduced ratings of perceived exertion (mean difference: 0.5 ± 0.7; 95% likely range: 0.1 to 0.9) and heart rate (mean difference: 3.6 ± 4.2 b∙min-1; 95% likely range: 1.3 to 5.8 b∙min-1) during exercise, with the effect on the latter dissipating as exercise intensity increased. Supplement × exercise intensity interactions were observed for respiratory exchange ratio (p = 0.004) and minute ventilation (p = 0.034). The results of the present study illustrate the clear, though often subtle, effects of caffeine on physiological responses to submaximal exercise. Researchers should be aware of these responses, particularly when evaluating the physiological effects of various experimental interventions.

  14. Aerobic interval training reduces vascular resistances during submaximal exercise in obese metabolic syndrome individuals.

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    Mora-Rodriguez, Ricardo; Fernandez-Elias, V E; Morales-Palomo, F; Pallares, J G; Ramirez-Jimenez, M; Ortega, J F

    2017-08-12

    The aim of this study was to determine the effects of high-intensity aerobic interval training (AIT) on exercise hemodynamics in metabolic syndrome (MetS) volunteers. Thirty-eight, MetS participants were randomly assigned to a training (TRAIN) or to a non-training control (CONT) group. TRAIN consisted of stationary interval cycling alternating bouts at 70-90% of maximal heart rate during 45 min day(-1) for 6 months. CONT maintained baseline physical activity and no changes in cardiovascular function or MetS factors were detected. In contrast, TRAIN increased cardiorespiratory fitness (14% in VO2PEAK; 95% CI 9-18%) and improved metabolic syndrome (-42% in Z score; 95% CI 83-1%). After TRAIN, the workload that elicited a VO2 of 1500 ml min(-1) increased 15% (95% CI 5-25%; P < 0.001). After TRAIN when subjects pedaled at an identical submaximal rate of oxygen consumption, cardiac output increased by 8% (95% CI 4-11%; P < 0.01) and stroke volume by 10% (95% CI, 6-14%; P < 0.005) being above the CONT group values at that time point. TRAIN reduced submaximal exercise heart rate (109 ± 15-106 ± 13 beats min(-1); P < 0.05), diastolic blood pressure (83 ± 8-75 ± 8 mmHg; P < 0.001) and systemic vascular resistances (P < 0.01) below CONT values. Double product was reduced only after TRAIN (18.2 ± 3.2-17.4 ± 2.4 bt min(-1) mmHg 10(-3); P < 0.05). The data suggest that intense aerobic interval training improves hemodynamics during submaximal exercise in MetS patients. Specifically, it reduces diastolic blood pressure, systemic vascular resistances, and the double product. The reduction in double product, suggests decreased myocardial oxygen demands which could prevent the occurrence of adverse cardiovascular events during exercise in this population. CLINICALTRIALS. NCT03019796.

  15. The Effect of Acute Sub-Maximal Endurance Exercise on Serum Angiogenic Indices in Sedentary Men

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    Kamal Ranjbar

    2014-06-01

    Full Text Available Background: Endurance training increases capillary density of skeletal muscle, but the molecular mechanism of this process is not yet clear. Therefore, the purpose of this study was to investigate the effect of acute sub maximal endurance exercise on serum levels of vascular endothelial growth factor (VEGF and matrix metaloproteinases 2 and 9 (MMP-2 and MMP-9 in sedentary men. Materials and Methods: Twelve healthy men (22.37±2.30 years, BMI=23.16 ±2.61 kg/mP 2 P participated in this study. Subjects exercised for 1h at 70% of VOR2R max, 3 days after the VOR2R max determination. Antecubital vein blood was collected at rest, immediately and 2h after the exercise. Serum VEGF, MMP-2 and MMP-9 were measured by ELISA methods5T. Results: Serum levels of VEGF and MMP-2 decreased immediately after the exercise. 2 hours after the exercise, serum levels of VEGF remained at a lower level but serum MMP-2 returned to its basal level. Also, serum levels of MMP-9 did not change significantly in response to exercise5T. Conclusion: Acute sub-maximal endurance exercise decreased the main factors involved in development of capillary density in sedentary men. This might to due to the fact that, sub maximal exercise could not provide the two main stimulating factors of angiogenesis, i.e. Shear stress and hypoxia. It could also be explained by the fact that the mechanism of development of capillary network following regular endurance training is different from that following an acute exercise5T.5T

  16. Normobaric Hypoxia and Submaximal Exercise Effects on Running Memory and Mood State in Women.

    Science.gov (United States)

    Seo, Yongsuk; Gerhart, Hayden D; Stavres, Jon; Fennell, Curtis; Draper, Shane; Glickman, Ellen L

    2017-07-01

    An acute bout of exercise can improve cognitive function in normoxic and hypoxic conditions. However, limited research supports the improvement of cognitive function and mood state in women. The purpose of this study was to examine the effects of hypoxia and exercise on working memory and mood state in women. There were 15 healthy women (age = 22 ± 2 yr) who completed the Automated Neuropsychological Assessment Metrics-4th Edition (ANAM), including the Running Memory Continuous Performance Task (RMCPT) and Total Mood Disturbance (TMD) in normoxia (21% O2), at rest in normoxia and hypoxia (12.5% O2), and during cycling exercise at 60% and 40% Vo2max in hypoxia. RMCPT was not significantly impaired at 30 (100.3 ± 17.2) and 60 (96.6 ± 17.3) min rest in hypoxia compared to baseline in normoxia (97.0 ± 17.0). However, RMCPT was significantly improved during exercise (106.7 ± 20.8) at 60% Vo2max compared to 60 min rest in hypoxia. Following 30 (-89.4 ± 48.3) and 60 min of exposure to hypoxia (-79.8 ± 55.9) at rest, TMD was impaired compared with baseline (-107.1 ± 46.2). TMD was significantly improved during exercise (-108.5 ± 42.7) at 40% Vo2max compared with 30 min rest in hypoxia. Also, RMCPT was significantly improved during exercise (104.0 ± 19.1) at 60% Vo2max compared to 60 min rest in hypoxia (96.6 ± 17.3). Hypoxia and an acute bout of exercise partially influence RMCPT and TMD. Furthermore, a moderate-intensity bout of exercise (60%) may be a more potent stimulant for improving cognitive function than low-intensity (40%) exercise. The present data should be considered by aeromedical personnel performing cognitive tasks in hypoxia.Seo Y, Gerhart HD, Stavres J, Fennell C, Draper S, Glickman EL. Normobaric hypoxia and submaximal exercise effects on running memory and mood state in women. Aerosp Med Hum Perform. 2017; 88(7):627-632.

  17. Reduced peripheral arterial blood flow with preserved cardiac output during submaximal bicycle exercise in elderly heart failure

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    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.

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

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    Julia Ratter

    2014-09-01

    [Ratter J, Radlinger L, Lucas C (2014 Several submaximal exercise tests are reliable, valid and acceptable in people with chronic pain, fibromyalgia or chronic fatigue: a systematic review. Journal of Physiotherapy 60: 144–150

  19. Substrate utilization during submaximal exercise in children with a severely obese parent

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    Eaves Audrey D

    2012-05-01

    Full Text Available Abstract Background We have reported a reduction in fatty acid oxidation (FAO at the whole-body level and in skeletal muscle in severely obese (BMI ≥ 40 kg/m2 individuals; this defect is retained in cell culture suggesting an inherent component. The purpose of the current study was to determine if an impairment in whole-body fatty acid oxidation (FAO was also evident in children with a severely obese parent. Methods Substrate utilization during submaximal exercise (cycle ergometer was determined in children ages 8–12 y with a severely obese parent (OP, n = 13 or two lean/non-obese (BMI range of 18 to 28 kg/m2 parents (LP, n = 13. A subgroup of subjects (n = 3/group performed 4 weeks of exercise training with substrate utilization measured after the intervention. Results The children did not differ in age (LP vs. OP, respectively (10.7 ± 0.5 vs. 10.2 ± 0.5 y, BMI percentile (65.3 ± 5.2 vs. 75.9 ± 7, Tanner Stage (1.4 ± 0.2 vs. 1.5 ± 0.2, VO2peak (40.3 ± 2.7 vs. 35.6 ± 2.6 ml/kg/min or physical activity levels (accelerometer. At the same absolute workload of 15 W (~38% VO2peak, RER was significantly (P ≤ 0.05 lower in LP vs. OP (0.83 ± 0.02 vs. 0.87 ± 0.01 which was reflected in a reduced reliance on FAO for energy production in the OP group (58.6 ± 5.1 vs. 43.1 ± 4.0% of energy needs during exercise from FAO. At a higher exercise intensity (~65% VO2peak there were no differences in substrate utilization between LP and OP. After exercise training RER tended to decrease (P = 0.06 at the 15 W workload, suggesting an increased reliance on FAO regardless of group. Conclusions These findings suggest that the decrement in FAO with severe obesity has an inherent component that may be overcome with exercise training.

  20. Application of "living high-training low" enhances cardiac function and skeletal muscle oxygenation during submaximal exercises in athletes.

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    Park, Hun-Young; Nam, Sang-Seok

    2017-03-31

    The aim of this study was to determine the efficiency of the application of living high-training low (LHTL) on cardiac function and skeletal muscle oxygenation during submaximal exercises compared with that of living low-training low (LLTL) in athletes. Male middle- and long-distance runners (n = 20) were randomly assigned into the LLTL group (n = 10, living at 1000-m altitude and training at 700-1330-m altitude) and the LHTL group (n = 10, living at simulated 3000-m altitude and training at 700-1330-m altitude). Their cardiac function and skeletal muscle oxygenation during submaximal exercises at sea level before and after training at each environmental condition were evaluated. There was a significant interaction only in the stroke volume (SV); however, the heart rate (HR), end-diastolic volume (EDV), and end-systolic volume (ESV) showed significant main effects within time; HR and SV significantly increased during training in the LHTL group compared with those in the LLTL group. EDV also significantly increased during training in both groups; however, the LHTL group had a higher increase than the LLTL group. ESV significantly increased during training in the LLTL group. There was no significant difference in the ejection fraction and cardiac output. The skeletal muscle oxygen profiles had no significant differences but improved in the LHTL group compared with those in the LLTL group. LHTL can yield favorable effects on cardiac function by improving the HR, SV, EDV, and ESV during submaximal exercises compared with LLTL in athletes.

  1. Analysing visual pattern of skin temperature during submaximal and maximal exercises

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    Balci, Gorkem Aybars; Basaran, Tahsin; Colakoglu, Muzaffer

    2016-01-01

    Aims of this study were to examine our hypotheses assuming that (a) skin temperature patterns would differ between submaximal exercise (SE) and graded maximal exercise test (GXT) and (b) thermal kinetics of Tskin occurring in SE and GXT might be similar in a homogenous cohort. Core temperature (Tcore) also observed in order to evaluate thermoregulatory responses to SE and GXT. Eleven moderately to well-trained male athletes were volunteered for the study (age: 22.2 ± 3.7 years; body mass: 73.8 ± 6.9 kg; height: 181 ± 6.3 cm; body surface area 1.93 ± 0.1 m2; body fat: 12.6% ± 4.2%; V ˙ O2max: 54 ± 9.9 mL min-1 kg-1). Under stabilized environmental conditions in climatic chamber, GXT to volitional exhaustion and 20-min SE at 60% of VO2max were performed on cycle ergometer. Thermal analyses were conducted in 2-min intervals throughout exercise tests. Tskin was monitored by a thermal camera, while Tcore was recorded via an ingestible telemetric temperature sensor. Thermal kinetic analyses showed that Tskin gradually decreased till the 7.58 ± 1.03th minutes, and then initiated to increase till the end of SE (Rsqr = 0.97), while Tskin gradually decreased throughout the GXT (Rsqr = 0.89). Decrease in the level of Tskin during the GXT was significantly below from the SE [F (4, 40) = 2.67, p = 0.07, ηp2 = 0.211]. In the meantime, Tcore continuously increased throughout the SE and GXT (p 0.05). However, total heat energies were calculated as 261.5 kJ/m2 and 416 kJ/m2 for GXT and SE, respectively (p exercises as expected. Tskin curves patterns found to be associated amongst participants at both GXT and SE. Therefore, Tskin kinetics may ensure an important data for monitoring thermoregulation in exercise.

  2. TEST-RETEST RELIABILITY OF THE AEROBIC POWER INDEX SUBMAXIMAL EXERCISE TEST IN CANCER PATIENTS

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    Bonnie J. Furzer

    2012-12-01

    Full Text Available The purpose of this study was to investigate the reliability of the Aerobic Power Index (API submaximal cardiorespiratory exercise test, as well as associated variables of oxygen uptake (ml·kg-1·min-1 and ratings of perceived exertion (RPE in cancer patients who are generally unable to complete maximal or lengthy aerobic fitness tests. Twenty male and female participants (11 male; 9 female aged between 18 and 70 y (mean = 53.28 ± 11. 82 y were recruited with medical consent within 4 weeks of completing chemotherapy treatment for a lymphohaematopoietic cancer (LHC. Of the twenty recruited participants' 2 were excluded from analysis due to disease relapse or complications unrelated to testing occurring within the month following testing. Intra-class correlation coefficient (ICC scores for power output (W·kg-1 and oxygen uptake (ml·kg-1·min-1 were highly reliable (R1 = 0.96 and 0.96, respectively and the ICC for RPE was moderately reliable (R1 = 0.83. Technical error of measurement results for power output (W·kg-1, oxygen uptake (ml·kg-1·min-1 and RPE were 0.11W·kg-1, 1.18 ml·kg-1·min-1 and 1.0 respectively. A Pearson's product-moment correlation demonstrated a strong relationship between power output (W·kg-1 and oxygen uptake (ml·kg-1·min-1 for both trials (r = 0.93 and 0.89, respectively. Results demonstrate that the API test is a highly reliable protocol for use with a LHC population and can be considered a clinically feasible, safe and tolerable exercise test

  3. Comparing the Effects of Rest and Massage on Return to Homeostasis Following Submaximal Aerobic Exercise: a Case Study.

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    Resnick, Portia B

    2016-03-01

    Postexercise massage can be used to help promote recovery from exercise on the cellular level, as well as systemically by increasing parasympathetic activity. No studies to date have been done to assess the effects of massage on postexercise metabolic changes, including excess postexercise oxygen consumption (EPOC). The purpose of this study was to compare the effects of massage recovery and resting recovery on a subject's heart rate variability and selected metabolic effects following a submaximal treadmill exercise session. One healthy 24-year-old female subject performed 30 minutes of submaximal treadmill exercise prior to resting or massage recovery sessions. Metabolic data were collected throughout the exercise sessions and at three 10 minute intervals postexercise. Heart rate variability was evaluated for 10 minutes after each of two 30-minute recovery sessions, either resting or massage. Heart rate returned to below resting levels (73 bpm) with 30 and 60 minutes of massage recovery (72 bpm and 63 bpm, respectively) compared to 30 and 60 minutes of resting recovery (77 bpm and 74 bpm, respectively). Heart rate variability data showed a more immediate shift to the parasympathetic state following 30 minutes of massage (1.152 LF/HF ratio) versus the 30-minute resting recovery (6.91 LF/HF ratio). It took 60 minutes of resting recovery to reach similar heart rate variability levels (1.216 LF/HF) found after 30 minutes of massage. Ventilations after 30 minutes of massage recovery averaged 7.1 bpm compared to 17.9 bpm after 30 minutes of resting recovery. No differences in EPOC were observed through either the resting or massage recovery based on the metabolic data collected. Massage was used to help the subject shift into parasympathetic activity more quickly than rest alone following a submaximal exercise session.

  4. Comparing the Effects of Rest and Massage on Return to Homeostasis Following Submaximal Aerobic Exercise: a Case Study

    Science.gov (United States)

    Resnick, Portia B.

    2016-01-01

    Introduction Postexercise massage can be used to help promote recovery from exercise on the cellular level, as well as systemically by increasing parasympathetic activity. No studies to date have been done to assess the effects of massage on postexercise metabolic changes, including excess postexercise oxygen consumption (EPOC). The purpose of this study was to compare the effects of massage recovery and resting recovery on a subject’s heart rate variability and selected metabolic effects following a submaximal treadmill exercise session. Methods One healthy 24-year-old female subject performed 30 minutes of submaximal treadmill exercise prior to resting or massage recovery sessions. Metabolic data were collected throughout the exercise sessions and at three 10 minute intervals postexercise. Heart rate variability was evaluated for 10 minutes after each of two 30-minute recovery sessions, either resting or massage. Results Heart rate returned to below resting levels (73 bpm) with 30 and 60 minutes of massage recovery (72 bpm and 63 bpm, respectively) compared to 30 and 60 minutes of resting recovery (77 bpm and 74 bpm, respectively). Heart rate variability data showed a more immediate shift to the parasympathetic state following 30 minutes of massage (1.152 LF/HF ratio) versus the 30-minute resting recovery (6.91 LF/HF ratio). It took 60 minutes of resting recovery to reach similar heart rate variability levels (1.216 LF/HF) found after 30 minutes of massage. Ventilations after 30 minutes of massage recovery averaged 7.1 bpm compared to 17.9 bpm after 30 minutes of resting recovery. Conclusions No differences in EPOC were observed through either the resting or massage recovery based on the metabolic data collected. Massage was used to help the subject shift into parasympathetic activity more quickly than rest alone following a submaximal exercise session. PMID:26977215

  5. Oxygen uptake efficiency slope, a new submaximal parameter in evaluating exercise capacity in chronic heart failure patients.

    Science.gov (United States)

    Van Laethem, Christophe; Bartunek, Jozef; Goethals, Marc; Nellens, Paul; Andries, Erik; Vanderheyden, Marc

    2005-01-01

    The oxygen uptake efficiency slope (OUES) is a new submaximal parameter which objectively predicts the maximal exercise capacity in children and healthy subjects. However, the usefulness of OUES in adult patients with and without advanced heart failure remains undetermined. The present study investigates the stability and the usefulness of OUES in adult cardiac patients with and without heart failure. Forty-five patients with advanced heart failure (group A) and 35 patients with ischemic heart disease but normal left ventricular ejection fraction (group B) performed a maximal exercise test. PeakVO2 and percentage of predicted peakVO2 were markers of maximal exercise capacity, whereas OUES, ventilatory anaerobic threshold (VAT), and slope VE/VCO2 were calculated as parameters of submaximal exercise. Group A patients had lower peakVO2 (P slope VE/VCO2 (P slope VE/VCO2, and OUES (all P slope VE/VCO2 (r = -.492, P failure patients unable to perform a maximal exercise test. Further studies are needed to confirm our hypothesis.

  6. Translation of submaximal exercise test responses to exercise prescription using the Talk Test.

    Science.gov (United States)

    Foster, Carl; Porcari, John P; Gibson, Mark; Wright, Glenn; Greany, John; Talati, Neepa; Recalde, Pedro

    2009-12-01

    The exercise intensity at the Talk Test (TT) has been shown to be highly correlated with objective physiological markers, a useful outcome marker in patients with heart disease, a useful tool for avoiding exertional ischemia, and responsive to both positive and negative changes in exercise capacity. This randomized observational study evaluated the ability of the intensity at the TT during exercise testing to define absolute training workloads. Sedentary adults (n = 14) performed an incremental Balke type exercise test (3.0-3.5 mph at 0% grade, +2% grade every 2 minutes). Heart rate (HR), rating of perceived exertion (RPE), and TT were evaluated at each stage. Subsequently, the subjects performed 3 x 20-minute exercise bouts with the workload over the last 10 minutes of each bout equal to the absolute intensity at the stage preceding the LP (LP-1), at the last positive stage of the TT (LP), and at the first equivocal stage of the TT (EQ). During LP-1, LP, and EQ, HR was 140 +/- 23, 151 +/- 20, and 160 +/- 21 bpm, or 73 +/- 11, 79 +/- 9, and 82 +/- 9 % HRmax; RPE (CR scale) was 3.6 +/- 1.5, 4.4 +/- 1.8, and 6.3 +/- 2.2. The TT Score-ranked as 1 = comfortable speech, 2 = slightly uncomfortable speech, and 3 = speech not comfortable-was 1.4 +/- 0.5, 1.8 +/- 0.4, and 2.6 +/- 0.5 LP-1, LP, and at EQ, LP, respectively. The results suggest that to prescribe absolute training intensity from the TT and to get appropriate HR, RPE, and TT responses in sedentary individuals during training, the workload needs to be based on the intensity approximately 1 stage (approximately 1.0-1.2 metabolic equivalents) below the LP stage observed during an incremental test.

  7. Gender differences in substrate utilization during submaximal exercise in endurance-trained subjects.

    Science.gov (United States)

    Roepstorff, Carsten; Steffensen, Charlotte H; Madsen, Marianne; Stallknecht, Bente; Kanstrup, Inge-Lis; Richter, Erik A; Kiens, Bente

    2002-02-01

    Substrate utilization across the leg during 90 min of bicycle exercise at 58% of peak oxygen uptake (VO(2 peak)) was studied in seven endurance-trained males and seven endurance-trained, eumenorrheic females by applying arteriovenous catheterization, stable isotopes, and muscle biopsies. The female and male groups were matched according to VO(2 peak) per kilogram of lean body mass, physical activity level, and training history of the subjects. All subjects consumed the same diet, well controlled in terms of nutrient composition as well as energy content, for 8 days preceding the experiment, and all females were tested in the midfollicular phase of the menstrual cycle. During exercise, respiratory exchange ratio (RER) and leg respiratory quotient (RQ) were similar in females and males. Myocellular triacylglycerol (TG) degradation was negligible in males but amounted to 12.4 +/- 3.2 mmol/kg dry wt in females and corresponded to 25.0 +/- 6.0 and 5.0 +/- 7.3% of total oxygen uptake in females and males, respectively (P < 0.05). Utilization of plasma fatty acids (12.0 +/- 2.5 and 9.6 +/- 1.5%), blood glucose (13.6 +/- 1.5 and 14.3 +/- 1.5%), and glycogen (48.5 +/- 4.9 and 42.8 +/- 2.1%) were similar in females and males. Thus, in females, measured substrate oxidation accounted for 99% of the leg oxygen uptake, whereas in males 28% of leg oxygen uptake was unaccounted for in terms of measured oxidized lipid substrates. These findings may indicate that males utilized additional lipid sources, presumably very low density lipoprotein-TG or TG located between muscle fibers. On the basis of RER and leg RQ, it is concluded that no gender difference existed in the relative contribution from carbohydrate and lipids to the oxidative metabolism across the leg during submaximal exercise at the same relative workload. However, an effect of gender appears to occur in the utilization of the different lipid sources.

  8. Identification of patients at low risk of dying after acute myocardial infarction, by simple clinical and submaximal exercise test criteria.

    Science.gov (United States)

    Campbell, S; A'Hern, R; Quigley, P; Vincent, R; Jewitt, D; Chamberlain, D

    1988-09-01

    A consecutive series of 559 hospital survivors of acute myocardial infarction aged less than 66 years were studied; 93 were designated prospectively as low-risk because they were suitable for early submaximal exercise testing and had none of the following clinical or exercise test 'risk factors': (1) angina for at least one month prior to infarction; (2) symptomatic ventricular arrhythmias, or (3) recurrent ischaemic pain, both after the first 24 h of infarction; (4) cardiac failure; (5) cardiomegaly; and (6) an abnormal exercise test (angina, ST-depression or poor blood pressure response). Altogether 301 patients were exercised; their mortality over a median follow-up of 2.4 years was 10.2%, versus 24.6% in the 258 patients not exercised (P = 0.0005). Absence of clinical 'risk factors' alone, in the exercised patients, identified 156 with a mortality of 5.4% versus 15.6% in the 145 with at least one clinical 'risk factor' (P = 0.004). The fully defined low-risk group comprised 93 of the former patients who had neither clinical nor exercise test 'risk factors'. None of these patients died compared with 19 of those with at least one 'risk factor' (mortality = 14.7%; P = 0.002). Their respective rates of non-fatal reinfarction were similar and never exceeded 5% per annum. Therefore, simple clinical and exercise test criteria can positively identify low-risk patients after infarction in whom secondary prevention may be inappropriate.

  9. Effects of Submaximal Aerobic Exercise on Regulatory T Cell Markers of Male Patients Suffering from Ischemic Heart Disease.

    Science.gov (United States)

    Raygan, Fariba; Sayyah, Mansour; Janesar Qamsari, Seyed Mohammad Reza; Nikoueinejad, Hassan; Sehat, Mojtaba

    2017-02-01

    There are confirmed beneficiary effects of exercise on atherosclerotic inflammation of ischemia-associated heart diseases. The purpose of this study was to evaluate the effect of aerobic exercise on T-regulatory cell markers of IL-35 as well as FoxP3 and T-helper2 marker of IL-33 in patients with ischemic heart disease (IHD). This research was performed on 44 asymptomatic male patients with ischemic heart disease. The participants were randomly assigned into two groups of submaximal aerobic exercise and control group. Blood samples were collected before and after the termination of the exercise protocol. Serum levels of IL-35 and IL-33 as well as the amount of FoxP3 gene expression in peripheral blood mononuclear cells were measured by Elisa and Real time PCR, respectively. Serum levels of IL-35 (p=0.001) as well as the amount of FoxP3 gene expression increased significantly (p=0.012)  in exercise group even after controlling the likely confounding effects of age, length of ischemia, duration of the disease, and the amount of such factors before exercise (p≤0.042). It seems that exercise may yield a better control of atherosclerotic inflammation in patients with ischemic heart disease through the induction of regulatory T cells.

  10. Interaction effects of time of day and sub-maximal treadmill exercise on the main determinants of blood fluidity.

    Science.gov (United States)

    Ahmadizad, Sajad; Bassami, Minoo

    2010-01-01

    The purpose of this study was to investigate the effects of time of day on responses of the main determinants of blood rheology to acute endurance exercise. Ten healthy male subjects (age, 26.9 +/- 5.5 yr) performed two bouts of running at 65% of VO2peak for 45 min on a motorised treadmill in the morning (08:00 h) and evening (20:00 h), which were followed by 30 min recovery. The two exercise trials were performed in two separate days with 7 days intervening. Haemorheological variables were measured before, immediately after exercise and after recovery. Haematocrit, haemoglobin and RBC count were increased significantly (p evening trials and normalised following recovery, irrespective of time of day. Plasma viscosity increased significantly (F2,18 = 12.4, p exercise in both trials and returned to pre-exercise level at the end of recovery. Baseline values (p exercise were significantly affected by time of day. Neither a significant main effect of exercise nor a significant (p > 0.05) time-of-day effect was found for plasma proteins. It was concluded that sub-maximal running at 08:00 or 20:00 h does not induce different responses in the main determinant of blood rheology.

  11. Regadenoson in Europe: first-year experience of regadenoson stress combined with submaximal exercise in patients undergoing myocardial perfusion scintigraphy.

    Science.gov (United States)

    Brinkert, M; Reyes, E; Walker, S; Latus, K; Maenhout, A; Mizumoto, R; Nkomo, C; Standbridge, K; Wechalekar, K; Underwood, S R

    2014-03-01

    Regadenoson was approved for clinical use in Europe in 2011. Since then, it has become the default form of stress at our institution. We have assessed the side-effect profile and tolerability of regadenoson in patients undergoing clinically indicated myocardial perfusion scintigraphy between July 2011 and July 2012. Clinical, stress and imaging data were recorded prospectively. Symptoms during stress were recorded and defined as mild, moderate or severe. An adverse event was defined as any symptom that persisted for more than 30 min or that required investigation or treatment. Of 1,764 consecutive patients, 1,581 (90%) received regadenoson combined with submaximal exercise unless contraindicated. Symptoms were common (63%) but transient and well-tolerated. The severity of symptoms was recorded in most patients as mild (84%). Dyspnoea (36%) and chest discomfort (12%) were the commonest side effects. Adverse events were reported in eight patients (0.5%), thought to be vasovagal in seven of these. All patients recovered fully without sequelae. There were no deaths, myocardial infarction or hospital admissions. Regadenoson stress was performed in 206 patients (12%) with asthma or chronic obstructive pulmonary disease (COPD) without bronchospasm or any other major side effect. We studied the symptom profile of regadenoson in the largest European cohort to date. Regadenoson combined with submaximal exercise was well tolerated, notably also in patients with asthma or COPD. The majority of regadenoson-related adverse events were vasovagal episodes without sequelae.

  12. Estimating Neural Control from Concentric vs. Eccentric Surface Electromyographic Representations during Fatiguing, Cyclic Submaximal Back Extension Exercises

    Directory of Open Access Journals (Sweden)

    Gerold R. Ebenbichler

    2017-05-01

    Full Text Available Purpose: To investigate the differences in neural control of back muscles activated during the eccentric vs. the concentric portions of a cyclic, submaximal, fatiguing trunk extension exercise via the analysis of amplitude and time-frequency parameters derived from surface electromyographic (SEMG data.Methods: Using back dynamometers, 87 healthy volunteers performed three maximum voluntary isometric trunk extensions (MVC's, an isometric trunk extension at 80% MVC, and 25 cyclic, dynamic trunk extensions at 50% MVC. Dynamic testing was performed with the trunk angular displacement ranging from 0° to 40° and the trunk angular velocity set at 20°/s. SEMG data was recorded bilaterally from the iliocostalis lumborum at L1, the longissimus dorsi at L2, and the multifidus muscles at L5. The initial value and slope of the root mean square (RMS-SEMG and the instantaneous median frequency (IMDF-SEMG estimates derived from the SEMG recorded during each exercise cycle were used to investigate the differences in MU control marking the eccentric vs. the concentric portions of the exercise.Results: During the concentric portions of the exercise, the initial RMS-SEMG values were almost twice those observed during the eccentric portions of the exercise. The RMS-SEMG values generally increased during the concentric portions of the exercise while they mostly remained unchanged during the eccentric portions of the exercise with significant differences between contraction types. Neither the initial IMDF-SEMG values nor the time-course of the IMDF-SEMG values significantly differed between the eccentric and the concentric portions of the exercise.Conclusions: The comparison of the investigated SEMG parameters revealed distinct neural control strategies during the eccentric vs. the concentric portions of the cyclic exercise. We explain these differences by relying upon the principles of orderly recruitment and common drive governing motor unit behavior.

  13. Dichloroacetate therapy attenuates the blood lactate response to submaximal exercise in patients with defects in mitochondrial energy metabolism.

    Science.gov (United States)

    Duncan, G E; Perkins, L A; Theriaque, D W; Neiberger, R E; Stacpoole, P W

    2004-04-01

    We determined acute and chronic effects of dichloroacetate (DCA) on maximal (MAX) and submaximal (SUB) exercise responses in patients with abnormal mitochondrial energetics. Subjects (n = 9) completed a MAX treadmill bout 1 h after ingesting 25 mg/kg DCA or placebo (PL). A 15-min SUB bout was completed the next day while receiving the same treatment. After a 1-d washout, MAX and SUB were repeated while receiving the alternate treatment (acute). Gas exchange and heart rate were measured throughout all tests. Blood lactate (Bla) was measured 0, 3, and 10 min after MAX, and 5, 10, and 15 min during SUB. MAX and SUB were repeated after 3 months of daily DCA or PL. After a 2-wk washout, a final MAX and SUB were completed after 3 months of alternate treatment (chronic). Average Bla during SUB was lower (P abnormal mitochondrial energetics.

  14. Cardiac autonomic dysfunction in chronic stroke women is attenuated after submaximal exercise test, as evaluated by linear and nonlinear analysis.

    Science.gov (United States)

    Francica, Juliana Valente; Bigongiari, Aline; Mochizuki, Luís; Scapini, Kátia Bilhar; Moraes, Oscar Albuquerque; Mostarda, Cristiano; Caperuto, Erico Chagas; Irigoyen, Maria Cláudia; De Angelis, Katia; Rodrigues, Bruno

    2015-09-29

    We evaluated cardiac autonomic modulation in women with chronic ischemic stroke (at least 4 years post-stroke) at rest and in response to submaximal exercise test. Fourteen post-stroke women (S group) and 10 healthy women (C group) participated in this study. Autonomic modulation (using linear and nonlinear analysis), blood pressure and metabolic variables at rest were evaluated immediately after the exercise test and during the recovery period (20 min). All participants underwent submaximal exercise test on cycle ergometer with gas analysis. At rest, the S group displayed higher lactate concentration, systolic (SBP) and diastolic blood pressure (DBP) values when compared to C group. Furthermore, the S group had lower heart rate variability (HRV) in time domain (SDNN: S = 30 ± 5 vs. 40 ± 8 ms; rMSSD: S = 14 ± 2 vs. C = 34 ± 3 ms), decreased high frequency band of pulse interval (S = 8.4 ± 2 vs. 33.1 ± 9 %) and 2V pattern of symbolic analysis (S = 17.3 ± 1 vs. 30 ± 3 %) (both indicators of cardiac vagal modulation) when compared to C group. Immediately after exercise, S group presented higher values of lactate, SBP, DBP and double product when compared to C group, as well as decreased heart rate recovery (HRR) measured at the first, second and third minutes. At recovery time, all HRV parameters in time and frequency domains improved in the S group; however, HF band remained lower when compared to C group. After the exercise test, women with chronic stroke presented reduced heart rate variability, reduced cardiac vagal modulation, as well as reduced HRR, while displayed an improvement of heart rate variability and cardiac vagal modulation when compared to their baseline. These results reinforce the importance of a physically active lifestyle for cardiovascular autonomic disorders observed in chronic stroke women.

  15. Effects of environmental temperature on physiological responses during submaximal and maximal exercises in soccer players

    Directory of Open Access Journals (Sweden)

    MiHyun No

    2016-09-01

    Conclusion: It is concluded that physiological responses and endurance exercise capacity are impaired under cool or hot conditions compared with moderate conditions, suggesting that environmental temperature conditions play an important role for exercise performance.

  16. Human skeletal muscle type 1 fibre distribution and response of stress-sensing proteins along the titin molecule after submaximal exhaustive exercise.

    Science.gov (United States)

    Koskinen, Satu O A; Kyröläinen, Heikki; Flink, Riina; Selänne, Harri P; Gagnon, Sheila S; Ahtiainen, Juha P; Nindl, Bradley C; Lehti, Maarit

    2017-11-01

    Early responses of stress-sensing proteins, muscle LIM protein (MLP), ankyrin repeat proteins (Ankrd1/CARP and Ankrd2/Arpp) and muscle-specific RING finger proteins (MuRF1 and MuRF2), along the titin molecule were investigated in the present experiment after submaximal exhaustive exercise. Ten healthy men performed continuous drop jumping unilaterally on a sledge apparatus with a submaximal height until complete exhaustion. Five stress-sensing proteins were analysed by mRNA measurements from biopsies obtained immediately and 3 h after the exercise from exercised vastus lateralis muscle while control biopsies were obtained from non-exercised legs before the exercise. Decreased maximal jump height and increased serum creatine kinase activities as indirect markers for muscle damage and HSP27 immunostainings on muscle biopsies as a direct marker for muscle damage indicated that the current exercised protocol caused muscle damage. mRNA levels for four (MLP, Ankrd1/CARP, MuRF1 and MuRF2) out of the five studied stress sensors significantly (p exercise. The magnitude of MLP and Ankrd2 responses was related to the proportion of type 1 myofibres. Our data showed that the submaximal exhaustive exercise with subject's own physical fitness level activates titin-based stretch-sensing proteins. These results suggest that both degenerative and regenerative pathways are activated in very early phase after the exercise or probably already during the exercise. Activation of these proteins represents an initial step forward adaptive remodelling of the exercised muscle and may also be involved in the initiation of myofibre repair.

  17. Met-enkephalin, beta-endorphin and cortisol responses to sub-maximal exercise after sleep disturbances.

    Science.gov (United States)

    Mougin, F; Simon-Rigaud, M L; Mougin, C; Bourdin, H; Jacquier, M C; Henriet, M T; Davenne, D; Kantelip, J P; Magnin, P; Gaillard, R C

    1992-01-01

    The present study compared the effects of partial sleep deprivation and the effects of an intake of a hypnotic compound (zolpidem) prior to bedtime, on sleep and on hormonal and metabolic adaptations to subsequent exercise. Sleep deprivation consisted of a delayed bedtime and an early getting-up time. Eight young subjects, who slept well and were highly trained athletes, were enrolled in this study. Sleep was recorded polygraphically and the following afternoon exercise was performed on a cycle ergometer for 30 min at 75% of maximal oxygen consumption (VO2max) after a 10-min warm up. Met-enkephalin, beta-endorphin, cortisol, and lactate concentrations were measured at rest and during exercise. The data obtained after experimental sleep, with and without medication were compared with those obtained in the reference condition with normal sleep. Both types of sleep reduction decreased the total sleep time, stage 2 sleep, and rapid eye movement sleep, whereas zolpidem administration did not modify either the duration of sleep or the sleep stages. After the reference night, plasma met-enkephalin did not show any significant change at the end of the submaximal exercise, whereas beta-endorphin, cortisol, and lactic acid concentrations increased significantly in all subjects. The changes in concentration in beta-endorphin were significantly related to the changes in cortisol (r = 0.78; P less than 0.01) and to the changes in plasma lactic acid (r = 0.58; P less than 0.05). Cortisol concentrations were also related to lactic acid values (r = 0.94; P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Acute dietary nitrate supplementation does not augment submaximal forearm exercise hyperemia in healthy young men

    National Research Council Canada - National Science Library

    Kim, Jin-Kwang; Moore, David J; Maurer, David G; Kim-Shapiro, Daniel B; Basu, Swati; Flanagan, Michael P; Skulas-Ray, Ann C; Kris-Etherton, Penny; Proctor, David N

    2015-01-01

    ... on exercising limb blood flow in humans. We hypothesized that acute dietary nitrate supplementation from beetroot juice would augment the increases in forearm blood flow, as well as the progressive dilation of the brachial artery...

  19. Prolonged submaximal eccentric exercise is associated with increased levels of plasma IL-6

    DEFF Research Database (Denmark)

    Rohde, Thomas; MacLean, D A; Richter, Erik

    1997-01-01

    To study the relationship between exercise-related muscle proteolysis and the cytokine response, a prolonged eccentric exercise model of one leg was used. Subjects performed two trials [a branched-chain amino acid (BCAA) supplementation and a control trial]. The release of amino acids from muscle...... during and after the eccentric exercise was decreased in the BCAA trial, suggesting a suppression of net muscle protein degradation. The plasma concentrations of interleukin (IL)-6 increased from 0.75 +/- 0.19 (preexercise) to 5.02 +/- 0.96 pg/ml (2 h postexercise) in the control trial and in the BCAA...... supplementation trial from 1.07 +/- 0.41 to 4.15 +/- 1.21 pg/ml. Eccentric exercise had no effect on the concentrations of neutrophils, lymphocytes, CD16+/CD56+, CD4+, CD8+, CD14+/CD38+, lymphocyte proliferative response, or cytotoxic activities. BCAA supplementation reduced the concentration of CD14+/CD38+ cells...

  20. Cerebral blood flow during submaximal and maximal dynamic exercise in humans

    DEFF Research Database (Denmark)

    Thomas, S N; Schroeder, T; Secher, N H

    1989-01-01

    Cerebral blood flow (CBF) in humans was measured at rest and during dynamic exercise on a cycle ergometer corresponding to 56% (range 27-85) of maximal O2 uptake (VO2max). Exercise bouts were performed by 16 male and female subjects, lasted 15 min each, and were carried out in a semisupine position....... CBF (133Xe clearance) was expressed as the initial slope index (ISI) and as the first compartment flow (F1). CBF at rest [ISI, 58 (range 45-73); F1, 76 (range 55-98) ml.100 g-1.min-1] increased during exercise [ISI to 79 (57-94) and F1 to 118 (75-164) ml.100 g-1.min-1, P less than 0.01]. CBF did...

  1. The Effect of Submaximal Exercise Preceded by Single Whole-Body Cryotherapy on the Markers of Oxidative Stress and Inflammation in Blood of Volleyball Players

    Directory of Open Access Journals (Sweden)

    Celestyna Mila-Kierzenkowska

    2013-01-01

    Full Text Available The aim of the study was to determine the effect of single whole-body cryotherapy (WBC session applied prior to submaximal exercise on the activity of antioxidant enzymes, the concentration of lipid peroxidation products, total oxidative status, and the level of cytokines in blood of volleyball players. The study group consisted of 18 male professional volleyball players, who were subjected to extremely cold air (−130∘C prior to exercise performed on cycloergometer. Blood samples were taken five times: before WBC, after WBC procedure, after exercise preceded by cryotherapy (WBC exercise, and before and after exercise without WBC (control exercise. The activity of catalase statistically significantly increased after control exercise. Moreover, the activity of catalase and superoxide dismutase was lower after WBC exercise than after control exercise (P<0.001. After WBC exercise, the level of IL-6 and IL-1β was also lower (P<0.001 than after control exercise. The obtained results may suggest that cryotherapy prior to exercise may have some antioxidant and anti-inflammatory properties. The relations between the level of studied oxidative stress and inflammatory markers may testify to the contribution of reactive oxygen species in cytokines release into the blood system in response to exercise and WBC.

  2. Core Temperature Measurement During Submaximal Exercise: Esophageal, Rectal, and Intestinal Temperatures

    Science.gov (United States)

    Lee, Stuart M. C.; Williams, W. Jon; Schneider, Suzanne M.

    2000-01-01

    The purpose of this study was to determine if intestinal temperature (Tin) might be in acceptable alternative to esophageal (Tes) and rectal temperature (Trec) to assess thermoregulation during supine exercise. We hypothesized that Tin would have values similar to Tes and a response time similar to Trec, but the rate of temperature change across time would not be different between measurement sites. Seven subjects completed a continuous supine protocol of 20 min of rest, 20 min of cycle exercise at 40% peak oxygen consumption (VO2pk), 20 min of cycle exercise at 65% V02pk, and 20 min of recovery. Tes, Trec, and Tin were recorded each min throughout the test. Temperatures were not different after 20 min of rest, but Trec was less than the Tes and Tin at the end of the 40% and 65% VO2pk stages. After 20 min of recovery, Tes was less than either Trec or Tin, which were not different from each other. Time to threshold for increased temperature from rest was greater for Trec than Tes but not different from Tin. Time to reach peak temperature was greater for Tin and Trec than Tes. Similarly, time to a decrease in temperature after exercise was greater for Trec than Tes, but not different from Tin. The rate of temperature change from threshold to the end of the 40% VO2pk stage was not different between measurement sites. However, the rate of change during recovery was more negative for Tes than Tin and Trec, which were different from each other. Measurement of Tin may he an acceptable alternative to Tes and Trec with an understanding of its limitations.

  3. Responses of Plasma Atrial Natriuretic Peptide to High Intensity Submaximal Exercise in the Heat,

    Science.gov (United States)

    1987-06-01

    been demonstrated that in the rat , cow and human adrenal tumor. ANP decreases ALDO synthesis (Atarashi et al.1984, Delean et al. . 1984, Goodfriend et al...observed in this study (Collins and Weiner. 1986). It has recently been demonstrated that hypothyroidism is characterized by decreased plasma levels of...anesthetized rats . Can J. Physiol. Pharmacol. 62: 819-826. Armstrong LE. Dziados JE (1986). Effects of heat exposure on the exercising adult. In: Bernhardt

  4. Pulmonary and leg VO2 during submaximal exercise: implications for muscular efficiency

    Science.gov (United States)

    Poole, D. C.; Gaesser, G. A.; Hogan, M. C.; Knight, D. R.; Wagner, P. D.

    1992-01-01

    Insights into muscle energetics during exercise (e.g., muscular efficiency) are often inferred from measurements of pulmonary gas exchange. This procedure presupposes that changes of pulmonary O2 (VO2) associated with increases of external work reflect accurately the increased muscle VO2. The present investigation addressed this issue directly by making simultaneous determinations of pulmonary and leg VO2 over a range of work rates calculated to elicit 20-90% of maximum VO2 on the basis of prior incremental (25 or 30 W/min) cycle ergometry. VO2 for both legs was calculated as the product of twice one-leg blood flow (constant-infusion thermodilution) and arteriovenous O2 content difference across the leg. Measurements were made 3-5 min after each work rate imposition to avoid incorporation of the VO2 slow component above the lactate threshold. For all 17 subjects, the slope of pulmonary VO2 (9.9 +/- 0.2 ml O2.W-1.min-1) was not different (P greater than 0.05) from that for leg VO2 (9.2 +/- 0.6 ml O2.W-1.min-1). Estimation of "delta" efficiency (i.e., delta work accomplished divided by delta energy expended, calculated from slope of VO2 vs. work rate and a caloric equivalent for O2 of 4.985 cal/ml) using pulmonary VO2 measurements (29.1 +/- 0.6%) was likewise not significantly different (P greater than 0.05) from that made using leg VO2 measurements (33.7 +/- 2.4%). These data suggest that the net VO2 cost of metabolic "support" processes outside the exercising legs changes little over a relatively broad range of exercise intensities. Thus, under the conditions of this investigation, changes of VO2 measured from expired gas reflected closely those occurring within the exercising legs.

  5. Ramadan fasting and the GH/IGF-1 axis of trained men during submaximal exercise.

    Science.gov (United States)

    Bouhlel, Ezzedine; Zaouali, Monia; Miled, Abdelhedi; Tabka, Zouhair; Bigard, Xavier; Shephard, Roy

    2008-01-01

    The aim of this study was to explore possible changes in body composition, blood glucose regulation, plasma growth hormone (GH), insulin-like growth factor 1 (IGF-1), insulin-like growth factor-binding protein-3 (IGFBP-3), and insulin concentrations of trained athletes in response to the intermittent fasting and dehydration of Ramadan observance. Nine trained male rugby players (age 19 +/- 2 years, height 1.78 +/- 0.74 m) were tested 3 times: before Ramadan (C), at the end of the first week (R1), and during the fourth week (R2). They performed a progressive cycle ergometer test at each visit. The work rate was increased in 6-min stages corresponding to 20, 30, 40, 50 and 60% of W max. Substrate oxidation was evaluated by indirect calorimetry. On each occasion, substrate and plasma hormone concentrations were measured at rest and at the end of the exercise. Ramadan fasting induced a significant decrease in body mass and body fat (R2 vs. C, p < 0.001). Plasma concentrations of glucose, insulin, GH, IGF-1 and IGFBP-3 did not change significantly between C and R2, either at rest or following exercise. Ramadan fasting induces positive changes in body composition without disturbing glucose regulation or activity of the GH/IGF-1 system. 2008 S. Karger AG, Basel.

  6. The Effect of Submaximal Exercise Preceded by Single Whole-Body Cryotherapy on the Markers of Oxidative Stress and Inflammation in Blood of Volleyball Players

    Science.gov (United States)

    Mila-Kierzenkowska, Celestyna; Szpinda, Michał; Augustyńska, Beata; Woźniak, Bartosz

    2013-01-01

    The aim of the study was to determine the effect of single whole-body cryotherapy (WBC) session applied prior to submaximal exercise on the activity of antioxidant enzymes, the concentration of lipid peroxidation products, total oxidative status, and the level of cytokines in blood of volleyball players. The study group consisted of 18 male professional volleyball players, who were subjected to extremely cold air (−130°C) prior to exercise performed on cycloergometer. Blood samples were taken five times: before WBC, after WBC procedure, after exercise preceded by cryotherapy (WBC exercise), and before and after exercise without WBC (control exercise). The activity of catalase statistically significantly increased after control exercise. Moreover, the activity of catalase and superoxide dismutase was lower after WBC exercise than after control exercise (P cryotherapy prior to exercise may have some antioxidant and anti-inflammatory properties. The relations between the level of studied oxidative stress and inflammatory markers may testify to the contribution of reactive oxygen species in cytokines release into the blood system in response to exercise and WBC. PMID:24489985

  7. Effects of a helium/oxygen mixture on individuals' lung function and metabolic cost during submaximal exercise for participants with obstructive lung diseases.

    Science.gov (United States)

    Häussermann, Sabine; Schulze, Anja; Katz, Ira M; Martin, Andrew R; Herpich, Christiane; Hunger, Theresa; Texereau, Joëlle

    2015-01-01

    Helium/oxygen therapies have been studied as a means to reduce the symptoms of obstructive lung diseases with inconclusive results in clinical trials. To better understand this variability in results, an exploratory physiological study was performed comparing the effects of helium/oxygen mixture (78%/22%) to that of medical air. The gas mixtures were administered to healthy, asthmatic, and chronic obstructive pulmonary disease (COPD) participants, both moderate and severe (6 participants in each disease group, a total of 30); at rest and during submaximal cycling exercise with equivalent work rates. Measurements of ventilatory parameters, forced spirometry, and ergospirometry were obtained. There was no statistical difference in ventilatory and cardiac responses to breathing helium/oxygen during submaximal exercise. For asthmatics, but not for the COPD participants, there was a statistically significant benefit in reduced metabolic cost, determined through measurement of oxygen uptake, for the same exercise work rate. However, the individual data show that there were a mixture of responders and nonresponders to helium/oxygen in all of the groups. The inconsistent response to helium/oxygen between individuals is perhaps the key drawback to the more effective and widespread use of helium/oxygen to increase exercise capacity and for other therapeutic applications.

  8. Effects of a helium/oxygen mixture on individuals’ lung function and metabolic cost during submaximal exercise for participants with obstructive lung diseases

    Science.gov (United States)

    Häussermann, Sabine; Schulze, Anja; Katz, Ira M; Martin, Andrew R; Herpich, Christiane; Hunger, Theresa; Texereau, Joëlle

    2015-01-01

    Background Helium/oxygen therapies have been studied as a means to reduce the symptoms of obstructive lung diseases with inconclusive results in clinical trials. To better understand this variability in results, an exploratory physiological study was performed comparing the effects of helium/oxygen mixture (78%/22%) to that of medical air. Methods The gas mixtures were administered to healthy, asthmatic, and chronic obstructive pulmonary disease (COPD) participants, both moderate and severe (6 participants in each disease group, a total of 30); at rest and during submaximal cycling exercise with equivalent work rates. Measurements of ventilatory parameters, forced spirometry, and ergospirometry were obtained. Results There was no statistical difference in ventilatory and cardiac responses to breathing helium/oxygen during submaximal exercise. For asthmatics, but not for the COPD participants, there was a statistically significant benefit in reduced metabolic cost, determined through measurement of oxygen uptake, for the same exercise work rate. However, the individual data show that there were a mixture of responders and nonresponders to helium/oxygen in all of the groups. Conclusion The inconsistent response to helium/oxygen between individuals is perhaps the key drawback to the more effective and widespread use of helium/oxygen to increase exercise capacity and for other therapeutic applications. PMID:26451096

  9. The effect of Sub-maximal exercise-rehabilitation program on cardio-respiratory endurance indexes and oxygen pulse in patients with spastic cerebral palsy

    Directory of Open Access Journals (Sweden)

    M Izadi

    2006-05-01

    Full Text Available Background: Physical or cardio-respiratory fitness are of the best important physiological variables in children with cerebral palsy (CP, but the researches on exercise response of individuals with CP are limited. Our aim was to determine the effect of sub-maximal rehabilitation program (aerobic exercise on maximal oxygen uptake, oxygen pulse and cardio- respiratory physiological variables of children with moderate to severe spastic cerebral palsy diplegia and compare with able-bodied children. Methods: In a controlled clinical trial study, 15 children with diplegia spastic cerebral palsy, were recruited on a voluntarily basis (experimental group and 18 subjects without neurological impairments selected as control group. In CP group, aerobic exercise program performed on the average of exercise intensity (144 beat per minute of heart rate, 3 times a week for 3 months. The time of each exercise session was 20-25 minutes. Dependent variables were measured in before (pretest and after (post test of rehabilitation program through Mac Master Protocol on Tantories cycle ergometer in CP group and compared with the control group. Results: The oxygen pulse (VO2/HR during ergometery protocol was significantly lower in CP group than normal group (P<0.05. No significant statistical difference in maximal oxygen uptake (VO2 max was found between groups. The rehabilitation program leads to little increase of this variable in CP group. After sub-maximal exercise in pretest and post test, the heart rate of patient group was greater than control group, and aerobic exercise leads to significant decrease in heart rate in CP patients(P<0.05. Conclusion: The patients with spastic cerebral palsy, because of high muscle tone, severe spasticity and involuntarily movements have higher energy cost and lower aerobic fitness than normal people. The rehabilitation exercise program can improve physiological function of muscle and cardio-respiratory endurance in these

  10. Evaluation of respiratory dynamics by volumetric capnography during submaximal exercise protocol of six minutes on treadmill in cystic fibrosis patients.

    Science.gov (United States)

    Parazzi, Paloma L F; Marson, Fernando A L; Ribeiro, Maria A G O; Schivinski, Camila I S; Ribeiro, José D

    2017-11-29

    Volumetric capnography provides the standard CO2 elimination by the volume expired per respiratory cycle and is a measure to assess pulmonary involvement. Thus, the objective of this study was to evaluate the respiratory dynamics of healthy control subjects and those with cystic fibrosis in a submaximal exercise protocol for six minutes on the treadmill, using volumetric capnography parameters (slope 3 [Slp3], Slp3/tidal volume [Slp3/TV], and slope 2 [Slp2]). This was a cross-sectional study with 128 subjects (cystic fibrosis, 64 subjects; controls, 64 subjects]. Participants underwent volumetric capnography before, during, and after six minutes on the treadmill. Statistical analysis was performed using the Friedman, Mann-Whitney, and Kruskal-Wallis tests, considering age and sex. An alpha=0.05 was considered. Six minutes on the treadmill evaluation: in cystic fibrosis, volumetric capnography parameters were different before, during, and after six minutes on the treadmill; the same was observed for the controls, except for Slp2. Regarding age, an Slp3 difference was observed in cystic fibrosis patients regardless of age, at all moments, and in controls for age≥12 years; a difference in Slp3/TV was observed in cystic fibrosis and controls, regardless of age; and an Slp2 difference in the cystic fibrosis, regardless of age. Regarding sex, Slp3 and Slp3/TV differences were observed in cystic fibrosis regardless of sex, and in controls in male participants; an Slp2 difference was observed in the cystic fibrosis and female participants. The analysis between groups (cystic fibrosis and controls) indicated that Slp3 and Slp3/TV has identified the CF, regardless of age and sex, while the Slp2 showed the CF considering age. Cystic fibrosis showed greater values of the parameters before, during, and after exercise, even when stratified by age and sex, which may indicate ventilation inhomogeneity in the peripheral pathways in the cystic fibrosis. Copyright © 2017 Sociedade

  11. Effects of a helium/oxygen mixture on individuals’ lung function and metabolic cost during submaximal exercise for participants with obstructive lung diseases

    Directory of Open Access Journals (Sweden)

    Häussermann S

    2015-09-01

    Full Text Available Sabine Häussermann,1 Anja Schulze,1 Ira M Katz,2,3 Andrew R Martin,4 Christiane Herpich,1 Theresa Hunger,1 Joëlle Texereau2 1Inamed GmbH, Gauting, Germany; 2Medical R&D, Air Liquide Santé International, Centre de Recherche Paris-Saclay, Les Loges-en-Josas, France; 3Department of Mechanical Engineering, Lafayette College, Easton, PA, USA; 4Department of Mechanical Engineering, University of Alberta, Edmonton, AB, CanadaBackground: Helium/oxygen therapies have been studied as a means to reduce the symptoms of obstructive lung diseases with inconclusive results in clinical trials. To better understand this variability in results, an exploratory physiological study was performed comparing the effects of helium/oxygen mixture (78%/22% to that of medical air.Methods: The gas mixtures were administered to healthy, asthmatic, and chronic obstructive pulmonary disease (COPD participants, both moderate and severe (6 participants in each disease group, a total of 30; at rest and during submaximal cycling exercise with equivalent work rates. Measurements of ventilatory parameters, forced spirometry, and ergospirometry were obtained.Results: There was no statistical difference in ventilatory and cardiac responses to breathing helium/oxygen during submaximal exercise. For asthmatics, but not for the COPD participants, there was a statistically significant benefit in reduced metabolic cost, determined through measurement of oxygen uptake, for the same exercise work rate. However, the individual data show that there were a mixture of responders and nonresponders to helium/oxygen in all of the groups.Conclusion: The inconsistent response to helium/oxygen between individuals is perhaps the key drawback to the more effective and widespread use of helium/oxygen to increase exercise capacity and for other therapeutic applications. Keywords: helium/oxygen, inspiratory capacity, oxygen uptake, COPD, asthma, obstructive airway diseases, exercise, heliox

  12. Submaximal exercise testing with near-infrared spectroscopy in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients compared to healthy controls: a case-control study.

    Science.gov (United States)

    Miller, Ruth R; Reid, W Darlene; Mattman, Andre; Yamabayashi, Cristiane; Steiner, Theodore; Parker, Shoshana; Gardy, Jennifer; Tang, Patrick; Patrick, David M

    2015-05-20

    Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating illness. Symptoms include profound fatigue and distinctive post-exertional malaise (PEM). We asked whether a submaximal exercise test would prove useful for identifying different patterns of tissue oxygen utilization in individuals with ME/CFS versus healthy subjects. Such a test has potential to aid with ME/CFS diagnosis, or to characterize patients' illness. A case-control study of 16 patients with ME/CFS compared to 16 healthy controls completing a 3-min handgrip protocol was performed. Response was measured using near-infrared spectroscopy, resulting in measurements of oxygenated (O2Hb) and deoxygenated hemoglobin (HHb) over wrist extensors and flexors. Changes in O2Hb (delta (d)O2Hb) and HHb (dHHb) absorbance between the first and last contraction were calculated, as were the force-time product of all contractions, measured as tension-time index (TTI), and ratings of perceived exertion (RPE). Individuals with ME/CFS demonstrated smaller dO2Hb and dHHb than controls. However, after adjusting for TTI and change in total hemoglobin (delta (d)tHb), differences in dO2Hb and dHHb were reduced, with large overlapping variances. RPE was significantly higher for cases than controls, particularly at rest. Relative to controls, participants with ME/CFS demonstrated higher RPE, lower TTI, and reduced dO2Hb and dHHb during repetitive handgrip exercise, although considerable variance was observed. With further study, submaximal exercise testing may prove useful for stratifying patients with a lower propensity for inducing PEM, and have the ability to establish baseline intensities for exercise prescription.

  13. Coconut Water Does Not Improve Markers of Hydration During Sub-maximal Exercise and Performance in a Subsequent Time Trial Compared with Water Alone.

    Science.gov (United States)

    Peart, Daniel J; Hensby, Andy; Shaw, Matthew P

    2017-06-01

    The purpose of this study was to compare markers of hydration during submaximal exercise and subsequent time trial performance when consuming water (PW) or coconut water (CW). There was also a secondary aim to assess the palatability of CW during exercise and voluntary intake during intense exercise. 10 males (age 27.9 ± 4.9 years, body mass 78.1 ± 10.1kg, average max minute power 300.2 ± 28.2W) completed 60-min of submaximal cycling followed by a 10-km time trial on two occasions. During these trials participants consumed either PW or CW in a randomized manner, drinking a 250 ml of the assigned drink between 10-15 min, 25-30 min and 40-45 min, and then drinking ad libitum from 55-min until the end of the time trial. Body mass and urine osmolality were recorded preexercise and then after 30-min, 60-min, and post time trial. Blood glucose, lactate, heart rate, rate of perceived exertion (RPE; 6-20) and ratings of thirst, sweetness, nausea, fullness and stomach upset (1 =very low/none, 5= very high) were recorded during each drink period. CW did not significantly improve time trial performance compared with PW (971.4 ± 50.5 and 966.6 ± 44.8 s respectively; p = .698) and there was also no significant differences between trials for any of the physiological variables measured. However there were subjective differences between the beverages for taste, resulting in a significantly reduced volume of voluntary intake in the CW trial (115 ± 95.41 ml and 208.7 ± 86.22 ml; p < .001).

  14. Vascular endothelial growth factor mRNA expression and arteriovenous balance in resonse to prolonged, submaximal exercise in humans

    DEFF Research Database (Denmark)

    Hiscock, N.; Fischer, C.P.; Pilegaard, Henriette

    2003-01-01

    VEGF, regulation of gene expression, exercise, angiogensis, skeletal muscle, peripheral vascular function......VEGF, regulation of gene expression, exercise, angiogensis, skeletal muscle, peripheral vascular function...

  15. Nuclear Forensic Field Exercise #1

    National Research Council Canada - National Science Library

    Larsson, Carey L; Hinton, Anthony

    2006-01-01

    .... As such, a radiological field exercise was held to review current forensic investigator methods and identify problem areas with respect to the collection of evidence from a contaminated crime scene...

  16. Racing Skiers and Swimmers’ Heart Electric Field during Ventricular Depolarization at Recovery Period after Moderate and Submaximal Physical Load

    Directory of Open Access Journals (Sweden)

    Svetlana V. Strelnikova

    2013-01-01

    Full Text Available The article presents the results of cardioelectrotopographic investigation of racing skiers and swimmers’ heart electric activity during ventricular depolarization at recovery period after moderate and submaximal physical load. Changes in ventricular depolarization time and ventricular depolarization phases ratio due to longer duration of the first and second cardioelectric potential inversions on the chest surface in racing skiers and less duration of the depolarization initial phase in swimmers were detected after moderate and submaximal load

  17. Effects of acute caffeinated coffee consumption on energy utilization related to glucose and lipid oxidation from short submaximal treadmill exercise in sedentary men.

    Science.gov (United States)

    Leelarungrayub, Donrawee; Sallepan, Maliwan; Charoenwattana, Sukanya

    2011-01-01

    Aim of this study was to evaluate the short term effect of coffee drinking on energy utilization in sedentary men. This study was performed in healthy sedentary men, who were randomized into three groups, control (n = 6), decaffeinated (n = 10), and caffeine (n = 10). The caffeine dose in coffee was rechecked and calculated for individual volunteers at 5 mg/kg. Baseline before drinking, complete blood count (CBC), glucose, antioxidant capacity, lipid peroxide, and caffeine in blood was evaluated. After drinking coffee for 1 hr, the submaximal exercise test with a modified Bruce protocol was carried out, and the VO2 and RER were analyzed individually at 80% maximal heart rate, then the blood was repeat evaluated. Three groups showed a nonsignificant difference in CBC results and physical characteristics. The caffeine group showed significant changes in all parameters; higher VO2 levels, (P = 0.037) and lower RER (P = 0.047), when compared to the baseline. Furthermore, the glucose level after exercise test increased significantly (P = 0.033) as well as lipid peroxide levels (P = 0.005), whereas antioxidant capacity did not change significantly (P = 0.759), when compared to the before exercise testing. In addition, the blood caffeine level also increased only in the caffeine group (P = 0.008). Short consumption of caffeinated coffee (5 mg/kg of caffeine), improves energy utilization and relates to glucose derivation and lipid oxidation.

  18. Beta2-adrenergic stimulation increases energy expenditure at rest, but not during submaximal exercise in active overweight men

    DEFF Research Database (Denmark)

    Onslev, Johan; Jacobson, Glenn A; Narkowicz, Christian K

    2017-01-01

    percentage and rac-formoterol-induced change in energy expenditure. During exercise, energy expenditure was not different between treatments, although carbohydrate oxidation was 15% higher (P = 0.021) for rac-formoterol than placebo. Rac-formoterol-induced shift in substrate choice from rest to exercise...

  19. Effect of acute exercise-induced fatigue on maximal rate of heart rate increase during submaximal cycling.

    Science.gov (United States)

    Thomson, Rebecca L; Rogers, Daniel K; Howe, Peter R C; Buckley, Jonathan D

    2016-01-01

    Different mathematical models were used to evaluate if the maximal rate of heart rate (HR) increase (rHRI) was related to reductions in exercise performance resulting from acute fatigue. Fourteen triathletes completed testing before and after a 2-h run. rHRI was assessed during 5 min of 100-W cycling and a sigmoidal (rHRIsig) and exponential (rHRIexp) model were applied. Exercise performance was assessed using a 5-min cycling time-trial. The run elicited reductions in time-trial performance (1.34 ± 0.19 to 1.25 ± 0.18 kJ · kg(-1), P exercise HR (73.0 ± 8.4 to 90.5 ± 11.4 beats · min(-1), P exercise and steady-state HR. rHRIsig was reduced following acute exercise-induced fatigue, and correlated with difference in performance.

  20. Neuromuscular blockade of slow twitch muscle fibres elevates muscle oxygen uptake and energy turnover during submaximal exercise in humans

    DEFF Research Database (Denmark)

    Krustrup, Peter; Secher, Niels; Relu, Mihai U.

    2008-01-01

    We tested the hypothesis that a greater activation of fast-twitch (FT) fibres during dynamic exercise leads to a higher muscle oxygen uptake (VO2 ) and energy turnover as well as a slower muscle on-kinetics. Subjects performed one-legged knee-extensor exercise for 10 min at an intensity of 30 W...... fibres, respectively. From 127 s of exercise, muscle VO2 was higher (P muscle VO2 response...... was slower (P muscle homogenate CP was lowered (P muscle lactate production was similar in CUR and CON (37.8 +/- 4.1 versus 35.2 +/- 6.2 mmol). Estimated total muscle ATP turnover was 19...

  1. The Effect of 4 Weeks Fixed and Mixed Intermittent Hypoxic Training (IHT) on Respiratory Metabolic and Acid-base Response of Capillary Blood During Submaximal Bicycle Exercise in Male Elite Taekwondo Players.

    Science.gov (United States)

    Park, Hun-Young; Sunoo, Sub; Nam, Sang-Seok

    2016-12-31

    The purpose of our study was to determine the effectiveness of 4 weeks fixed and mixed intermittent hypoxic training (IHT) and its difference from exercise training at sea-level on exercise load, respiratory metabolic and acid-base response of capillary blood during 80% maximal heart rate (HRmax) bicycle exercise in male elite Taekwondo players. Male elite Taekwondo players (n = 25 out of 33) were randomly assigned to training at sea-level (n = 8, control group), training at 16.5%O 2 (2000 m) simulated hypoxic condition (n = 9, fixed IHT group), and training at 14.5%O 2 (3000 m) up to 2 weeks and 16.5%O 2 (2000 m) simulated hypoxic condition (n = 8, mixed IHT group) for 3 weeks. We compared their average exercise load, respiratory metabolic, and acid-base response of the capillary blood during 80% HRmax submaximal bicycle exercise before and after 4 weeks training. Fixed and mixed IHT groups showed positive improvement in respiratory metabolic and acid-base response of the capillary blood during 80% HRmax submaximal bicycle exercise after 4 weeks training. However, all dependent variables showed no significant difference between fixed IHT and mix IHT. Results suggested that mixed and fixed IHT is effective in improving respiratory metabolic and acid-base response of capillary blood in male elite Taekwondo players. Thus, IHT could be a novel and effective method for improving exercise performance through respiratory metabolic and acid-base response.

  2. Acute citrulline malate supplementation improves upper- and lower-body submaximal weightlifting exercise performance in resistance-trained females.

    Science.gov (United States)

    Glenn, Jordan M; Gray, Michelle; Wethington, Lauren N; Stone, Matthew S; Stewart, Rodger W; Moyen, Nicole E

    2017-03-01

    Citrulline malate (CM) is a nonessential amino acid that increases exercise performance in males. However, based on physiological differences between genders, these results cannot be extrapolated to females. Therefore, the purpose of this investigation was to evaluate effects of acute CM supplementation on upper- and lower-body weightlifting performance in resistance-trained females. Fifteen females (23 ± 3 years) completed two randomized, double-blind trials consuming either CM (8 g dextrose + 8 g CM) or a placebo (8 g dextrose). One hour after supplement consumption, participants performed six sets each of upper- (i.e., bench press) and lower-body (i.e., leg press) exercises to failure at 80 % of previously established one-repetition maximum. Immediately after each set, repetitions completed, heart rate and rating of perceived exertion (RPE) were recorded. Repeated-measures analysis of variance indicated that subjects completed significantly (p = .045) more repetitions throughout upper-body exercise when consuming CM versus placebo (34.1 ± 5.7 vs. 32.9 ± 6.0, respectively). When consuming CM, similar significant (p = .03) improvements in total repetitions completed were observed for lower-body exercise (66.7 ± 30.5 vs. 55.13 ± 20.64, respectively). Overall RPE score was significantly lower (p = .02) in upper-body exercise when subjects consumed CM versus placebo (7.9 ± 0.3 and 8.6 ± 0.2, respectively). The supplement consumed exhibited no significant effects on heart rate at any time point. Acute CM supplementation in females increased upper- and lower-body resistance exercise performance and decreased RPE during upper-body exercise. These data indicate that athletes competing in sports with muscular endurance-based requirements may potentially improve performance by acutely supplementing CM.

  3. The Effect of Lower-Body Positive Pressure on the Cardiorespiratory Response at Rest and during Submaximal Running Exercise

    Directory of Open Access Journals (Sweden)

    Frédéric Stucky

    2018-01-01

    Full Text Available Anti-gravity treadmills facilitate locomotion by lower-body positive pressure (LBPP. Effects on cardiorespiratory regulation are unknown. Healthy men (30 ± 8 y, 178.3 ± 5.7 cm, 70.3 ± 8.0 kg; mean ± SD stood upright (n = 10 or ran (n = 9 at 9, 11, 13, and 15 km.h−1 (5 min stages with LBPP (0, 15, 40 mmHg. Cardiac output (CO, stroke volume (SV, heart rate (HR, blood pressure (BP, peripheral resistance (PR, and oxygen uptake (VO2 were monitored continuously. During standing, LBPP increased SV [by +29 ± 13 (+41% and +42 ± 15 (+60% ml, at 15 and 40 mmHg, respectively (p < 0.05] and decreased HR [by −15 ± 6 (−20% and −22 ± 9 (−29% bpm (p < 0.05] resulting in a transitory increase in CO [by +1.6 ± 1.0 (+32% and +2.0 ± 1.0 (+39% l.min−1 (p < 0.05] within the first seconds of LBPP. This was accompanied by a transitory decrease in end-tidal PO2 [by −5 ± 3 (−5% and −10 ± 4 (−10% mmHg (p < 0.05] and increase in VO2 [by +66 ± 53 (+26% and +116 ± 64 (+46% ml.min−1 (p < 0.05], suggesting increased venous return and pulmonary blood flow. The application of LBPP increased baroreflex sensitivity (BRS [by +1.8 ± 1.6 (+18% and +4.6 ± 3.7 (+47% at 15 and 40 mmHg LBPP, respectively P < 0.05]. After reaching steady-state exercise CO vs. VO2 relationships remained linear with similar slope and intercept for each participant (mean R2 = 0.84 ± 0.13 while MAP remained unchanged. It follows that (1 LBPP affects cardiorespiratory integration at the onset of exercise; (2 at a given LBPP, once reaching steady-state exercise, the cardiorespiratory load is reduced proportionally to the lower metabolic demand resulting from the body weight support; (3 the balance between cardiovascular response, oxygen delivery to the exercising muscles and blood pressure regulation is maintained at exercise steady-state; and (4 changes in baroreflex sensitivity may be involved in the regulation of cardiovascular parameters during LBPP.

  4. Heat storage in Asian elephants during submaximal exercise: behavioral regulation of thermoregulatory constraints on activity in endothermic gigantotherms.

    Science.gov (United States)

    Rowe, M F; Bakken, G S; Ratliff, J J; Langman, V A

    2013-05-15

    Gigantic size presents both opportunities and challenges in thermoregulation. Allometric scaling relationships suggest that gigantic animals have difficulty dissipating metabolic heat. Large body size permits the maintenance of fairly constant core body temperatures in ectothermic animals by means of gigantothermy. Conversely, gigantothermy combined with endothermic metabolic rate and activity likely results in heat production rates that exceed heat loss rates. In tropical environments, it has been suggested that a substantial rate of heat storage might result in a potentially lethal rise in core body temperature in both elephants and endothermic dinosaurs. However, the behavioral choice of nocturnal activity might reduce heat storage. We sought to test the hypothesis that there is a functionally significant relationship between heat storage and locomotion in Asian elephants (Elephas maximus), and model the thermoregulatory constraints on activity in elephants and a similarly sized migratory dinosaur, Edmontosaurus. Pre- and post-exercise (N=37 trials) measurements of core body temperature and skin temperature, using thermography were made in two adult female Asian elephants at the Audubon Zoo in New Orleans, LA, USA. Over ambient air temperatures ranging from 8 to 34.5°C, when elephants exercised in full sun, ~56 to 100% of active metabolic heat production was stored in core body tissues. We estimate that during nocturnal activity, in the absence of solar radiation, between 5 and 64% of metabolic heat production would be stored in core tissues. Potentially lethal rates of heat storage in active elephants and Edmontosaurus could be behaviorally regulated by nocturnal activity.

  5. Myocardial oxygen consumption at rest and during submaximal ...

    African Journals Online (AJOL)

    olayemitoyin

    2008-11-26

    Nov 26, 2008 ... Department of Physiology, JSS Medical College, Constituent College of JSS University, Mysore – 570015, ... determine the effect of increased adiposity on myocardial oxygen consumption at rest and during submaximal exercise in ... during exercise suggesting higher hemodynamic stress to the heart.

  6. Myocardial oxygen consumption at rest and during submaximal ...

    African Journals Online (AJOL)

    olayemitoyin

    2008-11-26

    Nov 26, 2008 ... and myocardial fatty acid utilization has been showed to decrease after weight loss from gastric bypass surgery or diet in obese persons (Fei ho et al., 1995,). During submaximal exercise and immediately after exercise, all three groups showed an increase in. RPP. The percentage increase in RPP was.

  7. Efeitos cardiovasculares da abstinência do fumo no repouso e durante o exercício submáximo em mulheres jovens fumantes Cardiovascular effects of smoking abstinence at rest and during submaximal exercise in young female smokers

    Directory of Open Access Journals (Sweden)

    Demilto Yamaguchi da Pureza

    2007-10-01

    Full Text Available OBJETIVO: O objetivo do presente estudo foi verificar o efeito da abstinência do fumo nas respostas cardiovasculares ao exercício físico progressivo submáximo em mulheres sedentárias fumantes. MÉTODOS: A pressão arterial sistólica (PAS e diastólica (PAD e a freqüência cardíaca (FC foram medidas de forma não invasiva em mulheres jovens não fumantes (MNF, n = 7 e fumantes (MF, n = 7, sem e com abstinência do fumo por 24 horas, em repouso, durante a realização do teste submáximo em bicicleta ergométrica e na recuperação. RESULTADOS: Em repouso, a PAD e a FC foram maiores nas MF (76 ± 1mmHg e 86 ± 5bpm quando comparadas com as MNF (68 ± 2mmHg e 72 ± 2bpm. Após 24 horas sem o tabaco essas medidas foram normalizadas. Durante o exercício, a PAS e a FC aumentaram nos grupos estudados. A PAD foi maior nas MF (~15% em relação às MNF em todos os estágios do exercício. Na situação de abstinência, a PAD aumentou somente no último estágio de exercício. Na recuperação tanto a PAD quanto a FC foram maiores nas MF, na situação basal e com abstinência de 24h, quando comparadas as MNF. CONCLUSÃO: Estes resultados demonstram que mulheres jovens fumantes apresentam prejuízo em parâmetros hemodinâmicos em repouso e em resposta ao exercício submáximo, os quais, podem ser em parte revertidos pela abstinência em curto prazo do uso do tabaco.OBJECTIVE: The objective of the present study was to verify the effect of tobacco smoking abstinence on cardiovascular responses to progressive submaximal physical exercise in sedentary female smokers. METHODS: Systolic blood pressure (SBP, diastolic blood pressure (DBP and heart rate (HR were non-invasively measured in young non-smoking women (NSW, n = 7 and smoking women (SW, n = 7, with and without tobacco abstinence for 24 hours, at rest, during the accomplishment of a submaximal bicycle ergometric test and recovery period. RESULTS: At rest, DBP and HR were higher in the SW group

  8. Myocardial oxygen consumption at rest and during submaximal ...

    African Journals Online (AJOL)

    Overweight and obesity are major risk factors for cardiovascular diseases. The objective of this study was to determine the effect of increased adiposity on myocardial oxygen consumption at rest and during submaximal exercise in young adults. The study consisted of 85 young adults (18-22years) grouped into 3 based on ...

  9. Influence of menstrual phase on ventilatory response to submaximal ...

    African Journals Online (AJOL)

    Objectives. To determine whether an increase in respiratory drive, due to elevated progesterone and oestrogen concentration during various menstrual phases, persists throughout prolonged submaximal exercise and potentially contributes to fatigue. Furthermore, to determine whether the difference in the ventilatory ...

  10. Addition of atropine to submaximal exercise stress testing in patients evaluated for suspected ischaemia with SPECT imaging: a randomized, placebo-controlled trial

    Energy Technology Data Exchange (ETDEWEB)

    Manganelli, Fiore; Sauro, Rosario; Di Lorenzo, Emilio; Rosato, Giuseppe [San Giuseppe Moscati Hospital, Department of Cardiology and Heart Surgery, Avellino (Italy); Spadafora, Marco; Varrella, Paola; Peluso, Giuseppina [San Giuseppe Moscati Hospital, Nuclear Medicine Unit, Avellino (Italy); Daniele, Stefania [Institute of Diagnostic and Nuclear Development (SDN), Naples (Italy); Cuocolo, Alberto [Institute of Diagnostic and Nuclear Development (SDN), Naples (Italy); University Federico II, Department of Biomorphological and Functional Sciences, Naples (Italy); National Council of Research, Institute of Biostructures and Bioimages, Naples (Italy)

    2011-02-15

    To evaluate the effects of the addition of atropine to exercise testing in patients who failed to achieve their target heart rate (HR) during stress myocardial perfusion imaging with single-photon emission computed tomography (SPECT). The study was a prospective, randomized, placebo-controlled design. Patients with suspected or known coronary artery disease who failed to achieve a target HR ({>=}85% of maximal predicted HR) during exercise SPECT imaging were randomized to receive intravenous atropine (n = 100) or placebo (n = 101). The two groups of patients did not differ with respect to demographic or clinical characteristics. A higher proportion of patients in the atropine group achieved the target HR compared to the placebo group (60% versus 3%, p < 0.0001). SPECT imaging was abnormal in a higher proportion of patients in the atropine group as compared to the placebo group (57% versus 42%, p < 0.05). Stress-induced myocardial ischaemia was present in more patients in the atropine group as compared to placebo (47% versus 29%, p < 0.01). In both groups of patients, no major side effects occurred. The addition of atropine at the end of exercise testing is more effective than placebo in raising HR to adequate levels, without additional risks of complications. The use of atropine in patients who initially failed to achieve their maximal predicted HR is associated with a higher probability of achieving a diagnostic myocardial perfusion study. (orig.)

  11. Muscular and pulmonary O2 uptake kinetics during moderate- and high-intensity sub-maximal knee-extensor exercise in humans

    DEFF Research Database (Denmark)

    Krustrup, Peter; Jones, Andrew M.; Wilkerson, Daryl P.

    2009-01-01

    The purpose of this investigation was to determine the contribution of muscle O2 consumption (m O2) to pulmonary O2 uptake (p O2) during both low-intensity (LI) and high-intensity (HI) knee extension exercise, and during subsequent recovery, in humans. Seven healthy male subjects (age 20-25 years...... kinetics for LI (30 +/- 3 vs. 30 +/- 3 s) but was slightly higher (Pintensities. In recovery, agreement between the responses was more limited both for LI (36 +/- 4 vs. 18 +/- 4 s, P

  12. A comparison of field methods to assess cardiorespiratory fitness among neophyte exercisers.

    Science.gov (United States)

    D'Alonzo, Karen T; Marbach, Kate; Vincent, Linda

    2006-07-01

    There is evidence to suggest that aerobic fitness levels among adults have declined markedly over the past 2 to 3 decades. Submaximal field measures of aerobic fitness, such as step tests, may now be seen as aversive by contemporary neophyte exercisers. In this study, a single-factor within-subjects (repeated measures) factorial design was used to compare three field measures of cardiorespiratory fitness among sedentary women: (a) the Queen's College step test (QCST), (b) the Rockport 1-mile walk (RW), and (c) a nonexercise estimation of VO(2) max (NE). The sample consisted of 31 racially and ethnically diverse female college students (mean age of 24.8 years). No significant within-subjects differences were found in the three measures of V0(2) max (F = 1.89, p = .17) among Black, Hispanic, White non-Hispanic, or Asian women, but relative perceived exertion scores were significantly higher for the QCST than for the RW (t = 9.79, p test and the NE test are comparable to the QCST as valid and reliable field measures of aerobic fitness and appear to be good alternatives to step testing among sedentary individuals.

  13. Submaximal arm crank ergometry : Effects of crank axis positioning on mechanical efficiency, physiological strain and perceived discomfort

    NARCIS (Netherlands)

    van Drongelen, S; Maas, J C; Scheel-Sailer, A; Van Der Woude, L H V

    2009-01-01

    PURPOSE: To evaluate the effect of the spatial orientation of the crank axis on mechanical efficiency, physiological strain and perceived discomfort in submaximal synchronous arm crank ergometry. METHODS: Twelve able-bodied individuals performed 12 submaximal exercise bouts of 3 minutes (women: 20

  14. Classroom to Community: Field Studies for Exercise Science Students

    Science.gov (United States)

    Melton, Deana; Dail, Teresa K.

    2017-01-01

    The field of kinesiology has seen growth in terms of the number of highly specialized subdisciplines, such as exercise physiology, motor learning, biomechanics, sport and exercise psychology, and fitness management. While some undergraduate students may be comfortable with a chosen concentration, others may enter the kinesiology curriculum lacking…

  15. Radiological field exercises for forensic investigators. Technical memorandum

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, C.L. [Defence R and D Canada (DRDC), Ottawa, Ontario (Canada); Clement, C.; Estan, D. [Canadian Nuclear Safety Commission, Ottawa, Ontario (Canada); McDiarmid, C.; Tessier, M. [Royal Canadian Mounted Police (RCMP), Ottawa, Ontario (Canada)

    2006-06-15

    A series of tabletop and field exercises were designed and executed to test traditional forensic investigation procedures in a crime scene with radioactive material present. This allowed for specific training needs of forensic identification specialists to be identified and revised procedures to be drafted. Two scenarios were exercised, first as tabletop discussions with the Royal Canadian Mounted Police (RCMP), the Canadian Nuclear Safety Commission (CNSC), and DRDC Ottawa, and then as field exercises with the participation of the RCMP and Ottawa Police Services (OPS) forensic investigators. These exercises produced a number of lessons learned with regard to protocols for forensic investigators and led to the development of a one-page fact sheet on performing forensic identification tasks in a radiation environment. (author)

  16. Field exercises are useful for improving public health emergency responses

    Directory of Open Access Journals (Sweden)

    Kirsty Hope

    2010-12-01

    Full Text Available Problem: Emergencies resulting from disease outbreaks and extreme environmental events present significant challenges for health services.Context: Preparing to effectively manage emergencies is a core activity in public health units. Field exercises support consolidation of biopreparedness by testing plans, identifying weaknesses, providing training opportunities and developing surge capacity.Action: An extended field exercise to test response to a novel influenza strain was conducted in New South Wales, Australia in September 2008, eight months before the influenza A(H1N1 2009 pandemic emerged. Lasting four days and involving over 300 participants, the exercise was set in the early response phase with the staggered presentation of 41 cases to 36 emergency departments in the health area. An additional 150 contacts were written into a complex scenario to test the public health response.Outcome: The subsequent pandemic emergence in mid-2009 offered a unique opportunity to assess the field exercise format for disaster preparedness. Most roles were adequately tested with recognized benefit during the actual pandemic response. However, the exercise did not adequately challenge the public health planning team that synthesizes surveillance data and forecasts risk, nor did it identify planning issues that became evident during the subsequent pandemic. Discussion: Field exercises offer the opportunity to rigorously test public health emergency preparedness but can be expensive and labour-intensive. Our exercise provided effective and timely preparation for the influenza A(H1N1 2009 pandemic but showed that more emphasis needs to be placed on the role and training of the public health planning team.

  17. Is an elevated submaximal heart rate associated with psychomotor slowness in young elite soccer players?

    NARCIS (Netherlands)

    Brink, Michel S.; Visscher, Chris; Schmikli, Sandor L.; Nederhof, E.; Lemmink, Koen A. P. M.

    2013-01-01

    The aim of the present study was to find early markers for overreaching that are applicable in sport practice. In a group of elite soccer players aged 1518, the stressrecovery balance and reaction times before and after exercise were assessed. Overreaching was indicated by an elevated submaximal

  18. Assessment of cardiorespiratory fitness using submaximal protocol in older adults with mood disorder and Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Natacha Alves de Oliveira

    2013-01-01

    Full Text Available BACKGROUND: Evidence has shown benefits for mental health through aerobic training oriented in percentage of VO2max, indicating the importance of this variable for clinical practice. OBJECTIVE: To validate a method for estimating VO2max using a submaximal protocol in elderly patients with clinically diagnosis as major depressive disorder (MDD and Parkinson's disease (PD. METHODS: The sample comprised 18 patients (64.22 ± 9.92 years with MDD (n = 7 and with PD (n = 11. Three evaluations were performed: I disease staging, II direct measurement of VO2max and III submaximal exercise test. Linear regression was performed to verify the accuracy of estimation in VO2max established in ergospirometry and the predicted VO2max from the submaximal test measurement. We also analyzed the correlation between the Bland-Altman procedures. RESULTS: The regression analysis showed that VO2max values estimated by submaximal protocol associated with the VO2max measured, both in absolute values (R² = 0.65; SEE = 0.26; p < 0.001 and the relative (R² = 0.56; SEE = 3.70; p < 0.001. The Bland-Altman plots for analysis of agreement of showed a good correlation between the two measures. DISCUSSION: The VO2max predicted by submaximal protocol demonstrated satisfactory criterion validity and simple execution compared to ergospirometry.

  19. Which factors determine the freely chosen cadence during submaximal cycling?

    Science.gov (United States)

    Vercruyssen, Fabrice; Brisswalter, Jeanick

    2010-03-01

    The present review of cycling science focuses on the identification of criteria that affect the freely chosen cadence (FCC) during submaximal exercise of short and prolonged durations. Cadence selection during submaximal cycling constitutes a potential parameter affecting the endurance performance in subjects of varying aerobic fitness level and experience. The activity constraints such as specificity (e.g. cycle bout of triathlon) and exercise duration may play an important role in the selection of cadence and must be taken into consideration in the task description. The 'holistic' approach of this review is based on a multifactorial analysis considering the cycling constraints, and the physiological and biomechanical factors of cadence selection so as to establish any interrelationships between these factors. During cycle bouts of short duration (<15 min), it has been well argued that experienced cyclists, trained runners and triathletes adopt high cadences (80-100 rpm) systematically above the energetically optimal cadence (EOC) at which the oxygen uptake is minimal (55-65 rpm). The choice of a high cadence has been shown to be dependent upon several factors, such as the aerobic fitness level, the reduction in forces applied to the cranks, the lower extremity net joint moments and minimal neuromuscular fatigue. However, with increasing exercise duration the FCC has been reported to be close to the EOC exclusively in endurance athletes practising a variety of activities, suggesting an impact of training mode on the muscular adaptations and the organisation of the movement pattern. Copyright 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  20. Eight weeks of intermittent hypoxic training improves submaximal physiological variables in highly trained runners.

    Science.gov (United States)

    Holliss, Ben A; Burden, Richard J; Jones, Andrew M; Pedlar, Charles R

    2014-08-01

    It is unclear whether intermittent hypoxic training (IHT) results in improvements in physiological variables associated with endurance running. Twelve highly trained runners (VO2peak 70.0 ± 3.5 ml·kg-1·min-1) performed incremental treadmill tests to exhaustion in normobaric normoxia and hypoxia (16.0% FIO2) to assess submaximal and maximal physiological variables and the limit of tolerance (T-Lim). Participants then completed 8 weeks of moderate to heavy intensity normoxic training (control [CONT]) or IHT (twice weekly 40 minutes runs, in combination with habitual training), in a single blinded manner, before repeating the treadmill tests. Submaximal heart rate decreased significantly more after IHT (-5 ± 5 b·min-1; p = 0.001) than after CONT ( -1 ± 5 b·min-1; p = 0.021). Changes in submaximal V[Combining Dot Above]O2 were significantly different between groups (p ≤ 0.05); decreasing in the IHT group in hypoxia (-2.6 ± 1.7 ml·kg-1·min-1; p = 0.001) and increasing in the CONT group in normoxia (+1.1 ± 2.1 ml·kg-1·min-1; p = 0.012). There were no VO2peak changes within either group, and while T-Lim improved post-IHT in hypoxia (p = 0.031), there were no significant differences between groups. Intermittent hypoxic training resulted in a degree of enhanced cardiovascular fitness that was evident during submaximal, but not maximal intensity exercise. These results suggest that moderate to heavy intensity IHT provides a mean of improving the capacity for submaximal exercise and may be useful for pre-acclimatization for subsequent exercise in hypoxia, but additional research is required to establish its efficacy for athletic performance at sea level.

  1. Modelling Mass Casualty Decontamination Systems Informed by Field Exercise Data

    Directory of Open Access Journals (Sweden)

    Richard Amlôt

    2012-10-01

    Full Text Available In the event of a large-scale chemical release in the UK decontamination of ambulant casualties would be undertaken by the Fire and Rescue Service (FRS. The aim of this study was to track the movement of volunteer casualties at two mass decontamination field exercises using passive Radio Frequency Identification tags and detection mats that were placed at pre-defined locations. The exercise data were then used to inform a computer model of the FRS component of the mass decontamination process. Having removed all clothing and having showered, the re-dressing (termed re-robing of casualties was found to be a bottleneck in the mass decontamination process during both exercises. Computer simulations showed that increasing the capacity of each lane of the re-robe section to accommodate 10 rather than five casualties would be optimal in general, but that a capacity of 15 might be required to accommodate vulnerable individuals. If the duration of the shower was decreased from three minutes to one minute then a per lane re-robe capacity of 20 might be necessary to maximise the throughput of casualties. In conclusion, one practical enhancement to the FRS response may be to provide at least one additional re-robe section per mass decontamination unit.

  2. Modelling Mass Casualty Decontamination Systems Informed by Field Exercise Data

    Science.gov (United States)

    Egan, Joseph R.; Amlôt, Richard

    2012-01-01

    In the event of a large-scale chemical release in the UK decontamination of ambulant casualties would be undertaken by the Fire and Rescue Service (FRS). The aim of this study was to track the movement of volunteer casualties at two mass decontamination field exercises using passive Radio Frequency Identification tags and detection mats that were placed at pre-defined locations. The exercise data were then used to inform a computer model of the FRS component of the mass decontamination process. Having removed all clothing and having showered, the re-dressing (termed re-robing) of casualties was found to be a bottleneck in the mass decontamination process during both exercises. Computer simulations showed that increasing the capacity of each lane of the re-robe section to accommodate 10 rather than five casualties would be optimal in general, but that a capacity of 15 might be required to accommodate vulnerable individuals. If the duration of the shower was decreased from three minutes to one minute then a per lane re-robe capacity of 20 might be necessary to maximise the throughput of casualties. In conclusion, one practical enhancement to the FRS response may be to provide at least one additional re-robe section per mass decontamination unit. PMID:23202768

  3. Prolonged administration of recombinant human erythropoietin increases submaximal performance more than maximal aerobic capacity

    DEFF Research Database (Denmark)

    Thomsen, J J; Rentsch, R L; Robach, P

    2007-01-01

    The effects of recombinant human erythropoietin (rHuEpo) treatment on aerobic power (VO2max) are well documented, but little is known about the effects of rHuEpo on submaximal exercise performance. The present study investigated the effect on performance (ergometer cycling, 20-30 min at 80......HuEpo treatment VO2max increased (PVO2max) was increased by 54.0 and 54.3% (P... week 11), TTE was decreased by 26.8% as compared to pre rHuEpo administration. In conclusion, in healthy non-athlete subjects rHuEpo administration prolongs submaximal exercise performance by about 54% independently of the approximately 12% increase in VO2max....

  4. Walking the Talk: Continuous Improvement of a Quality Management Field Exercise

    Science.gov (United States)

    Coy, Steven; Adams, Jeffery

    2012-01-01

    This article provides results from a three semester case study of the pedagogical efficacy of an innovative quality management field exercise. A series of direct and indirect measures were used to assess the extent to which the field exercise met a set of learning objectives. The results indicate that the assessment framework is useful in…

  5. Construct validation of a non-exercise measure of cardiorespiratory fitness in older adults

    Directory of Open Access Journals (Sweden)

    Kramer Arthur F

    2010-02-01

    Full Text Available Abstract Background Cardiorespiratory fitness (CRF is associated with a decreased risk of all-cause mortality but is rarely assessed in medical settings due to burdens of time, cost, risk, and resources. The purpose of this study was to test the construct validity of a regression equation developed by Jurca and colleagues (2005 to estimate CRF without exercise testing in community dwelling older adults. Methods Participants (n = 172 aged 60 to 80 years with no contraindications to submaximal or maximal exercise testing completed a maximal graded exercise test (GXT and the submaximal Rockport 1-mile walk test on separate occasions. Data included in the regression equation (age, sex, body mass index, resting heart rate, and physical activity were obtained via measurement or self-report. Participants also reported presence of cardiovascular conditions. Results The multiple R for the regression equation was .72, p and CRF estimated from this equation was significantly correlated with the MET value from the GXT (r = 0.66 and with CRF estimated from submaximal field testing (r = 0.67. All three CRF indices were significantly and inversely associated with reporting more cardiovascular conditions. Conclusions This research provides preliminary evidence that a non-exercise estimate of CRF is at least as valid as field test estimates of CRF and represents a low-risk, low-cost, and expedient method for estimating fitness in older adults.

  6. Low doses of caffeine reduce heart rate during submaximal cycle ergometry

    Directory of Open Access Journals (Sweden)

    Wetter Thomas J

    2007-10-01

    Full Text Available Abstract Background The purpose of this study was to examine the cardiovascular effects of two low-levels of caffeine ingestion in non habitual caffeine users at various submaximal and maximal exercise intensities. Methods Nine male subjects (19–25 yr; 83.3 ± 3.1 kg; 184 ± 2 cm, underwent three testing sessions administered in a randomized and double-blind fashion. During each session, subjects were provided 4 oz of water and a gelatin capsule containing a placebo, 1.5 mg/kg caffeine, or 3.0 mg/kg caffeine. After thirty minutes of rest, a warm-up (30 Watts for 2 min the pedal rate of 60 rpm was maintained at a steady-state output of 60 watts for five minutes; increased to 120 watts for five minutes and to 180 watts for five minutes. After a 2 min rest the workload was 180 watts for one minute and increased by 30 watts every minute until exhaustion. Heart rate (HR was measured during the last 15-seconds of each minute of submaximal exercise. Systolic blood pressure (BP was measured at rest and during each of the three sub-maximal steady state power outputs. Minute ventilation (VE, Tidal volume (VT, Breathing frequency (Bf, Rating of perceived exertion (RPE, Respiratory exchange ratio (RER, and Oxygen consumption (VO2 were measured at rest and during each minute of exercise. Results Caffeine at 1.5 and 3.0 mg/kg body weight significantly lowered (p E, VT, VO2, RPE, maximal power output or time to exhaustion. Conclusion In non habitual caffeine users it appears that consuming a caffeine pill (1.5 & 3.0 mg/kg at a dose comparable to 1–3 cups of coffee lowers heart rate during submaximal exercise but not at near maximal and maximal exercise. In addition, this caffeine dose also only appears to affect systolic blood pressure at rest but not during cycling exercise.

  7. [Comparison of submaximal front crawl and breast stroke swimming in relation to energy expenditure].

    Science.gov (United States)

    Sugiyama, K; Katamoto, S

    1992-11-01

    The purpose of this study was to compare the energy expenditure during submaximal front crawl (Fr) and breast stroke (Br) swimming. Six male college swimmers performed submaximal and maximal exercise tests in both styles in a swimming flume. In submaximal exercise tests, they swam at the following given velocities for 5 min, Br: 0.3, 0.5 and 0.7 m/sec; Fr: 0.3, 0.5, 0.7 and 0.9 m/sec. In maximal exercise tests, following submaximal swimming at 0.9 m/sec in Br and 1.1 m/sec in Fr, swimming velocity was increased progressively by 0.1 m/sec every 1 min until the subjects reached to voluntary exhaustion. VO2max obtained from the maximal swimming tests in Br and Fr were 4.27 and 4.18 l/min, respectively. And there was no significant difference between these two values. VO2 during Br and Fr swimming at four and five submaximal velocities were 1.06, 1.30, 1.79, 2.65 l/min and 1.17, 1.34, 1.63, 2.04, 3.05 l/min, respectively. And, it was found that VO2 at 0.3 and 0.9 m/sec were significantly different (p styles curvilinearly increased with swimming velocity, and these relationships were well fitted for the regression equation of the second order (Br: y = 3.84625x2 - 1.95914x + 1.310463,r2 = 0.999 (p < 0.05), Fr: y = 3.233446x2 - 2.28136x + 1.611524, r2 = 0.979 (p < 0.05)). It was calculated that the two curves crossed at a point on 0.49 m/sec, and that VO2 at this point was 1.27 l/min. This value equivalented to 30.4% VO2max in Br and 29.7% VO2max in Fr.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Exercises

    Science.gov (United States)

    ... exercising. Count out loud as you do the exercises. View Chronic Obstructive Pulmonary Disease (COPD) Home Techniques to ... Intimacy Importance of Being Together Body Changes with Age Communicating with Your Partner Exercise and Sexual Activity Less Strenuous Positions for Sexual ...

  9. Effects of music tempo upon submaximal cycling performance.

    Science.gov (United States)

    Waterhouse, J; Hudson, P; Edwards, B

    2010-08-01

    In an in vivo laboratory controlled study, 12 healthy male students cycled at self-chosen work-rates while listening to a program of six popular music tracks of different tempi. The program lasted about 25 min and was performed on three occasions--unknown to the participants, its tempo was normal, increased by 10% or decreased by 10%. Work done, distance covered and cadence were measured at the end of each track, as were heart rate and subjective measures of exertion, thermal comfort and how much the music was liked. Speeding up the music program increased distance covered/unit time, power and pedal cadence by 2.1%, 3.5% and 0.7%, respectively; slowing the program produced falls of 3.8%, 9.8% and 5.9%. Average heart rate changes were +0.1% (faster program) and -2.2% (slower program). Perceived exertion and how much the music was liked increased (faster program) by 2.4% and 1.3%, respectively, and decreased (slower program) by 3.6% and 35.4%. That is, healthy individuals performing submaximal exercise not only worked harder with faster music but also chose to do so and enjoyed the music more when it was played at a faster tempo. Implications of these findings for improving training regimens are discussed.

  10. Effect of inspiratory muscle warm-up on submaximal rowing performance.

    Science.gov (United States)

    Arend, Mati; Mäestu, Jarek; Kivastik, Jana; Rämson, Raul; Jürimäe, Jaak

    2015-01-01

    Performing inspiratory muscle warm-up might increase exercise performance. The aim of this study was to investigate the impact of inspiratory muscle warm-up to submaximal rowing performance and to find if there is an effect on lactic acid accumulation and breathing parameters. Ten competitive male rowers aged between 19 and 27 years (age, 23.1 ± 3.8 years; height, 188.1 ± 6.3 cm; body mass, 85.6 ± 6.6 kg) were tested 3 times. During the first visit, maximal inspiratory pressure (MIP) assessment and the incremental rowing test were performed to measure maximal oxygen consumption and maximal aerobic power (Pamax). A submaximal intensity (90% Pamax) rowing test was performed twice with the standard rowing warm-up as test 1 and with the standard rowing warm-up and specific inspiratory muscle warm-up as test 2. During the 2 experimental tests, distance, duration, heart rate, breathing frequency, ventilation, peak oxygen consumption, and blood lactate concentration were measured. The only value that showed a significant difference between the test 1 and test 2 was breathing frequency (52.2 ± 6.8 vs. 53.1 ± 6.8, respectively). Heart rate and ventilation showed a tendency to decrease and increase, respectively, after the inspiratory muscle warm-up (p < 0.1). Despite some changes in respiratory parameters, the use of 40% MIP intensity warm-up is not suggested if the mean intensity of the competition is at submaximal level (at approximately 90% maximal oxygen consumption). In conclusion, the warm-up protocol of the respiratory muscles used in this study does not have a significant influence on submaximal endurance performance in highly trained male rowers.

  11. Muscle and intensity based hamstring exercise classification in elite female track and field athletes: implications for exercise selection during rehabilitation

    Directory of Open Access Journals (Sweden)

    Tsaklis P

    2015-06-01

    Full Text Available Panagiotis Tsaklis,1,2 Nikos Malliaropoulos,3–5,10 Jurdan Mendiguchia,6 Vasileios Korakakis,7–9 Kyriakos Tsapralis,11 Debasish Pyne,5 Peter Malliaras101Department of Physiotherapy, Laboratory of Biomechanics and Ergonomics, Alexander Technological Educational Institute of Thessaloniki, Thessaloniki, Greece; 2Department of Mechanical Engineering, Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA; 3National Track and Field Centre, Sports Injury Clinic, Sports Medicine Clinic of SEGAS, 4Thessaloniki Sports Medicine Clinic, Thessaloniki, Greece; 5Rheumatology Department, Sports Medicine Clinic, Mile End Hospital, London, UK; 6Department of Physical Therapy, Zentrum Rehabilitation and Performance Center, Pamplona, Spain; 7Aspetar, Orthopaedic and Sports Medicine Hospital, Doha, Qatar; 8Faculty of Physical Education and Sport Science, University of Thessaly, Trikala, 9Hellenic Orthopaedic Manipulative Therapy Diploma, Athens, Greece; 10Centre for Sports and Exercise Medicine, Queen Mary, University of London, London, UK; 11K Tsapralis Isokinetic Medical Group, Bologna, ItalyBackground: Hamstring injuries are common in many sports, including track and field. Strains occur in different parts of the hamstring muscle but very little is known about whether common hamstring loading exercises specifically load different hamstring components. The purpose of this study was to investigate muscle activation of different components of the hamstring muscle during common hamstring loading exercises.Methods: Twenty elite female track and field athletes were recruited into this study, which had a single-sample, repeated-measures design. Each athlete performed ten hamstring loading exercises, and an electromyogram (EMG was recorded from the biceps femoris and semitendinosus components of the hamstring. Hamstring EMG during maximal voluntary isometric contraction (MVIC was used to normalize the mean data across ten repetitions of each

  12. Neuromuscular function of the quadriceps muscle during isometric maximal, submaximal and submaximal fatiguing voluntary contractions in knee osteoarthrosis patients.

    Directory of Open Access Journals (Sweden)

    Anett Mau-Moeller

    and neuromuscular activation, but also with an impaired position and torque control at submaximal torque levels, an altered EMG-torque relationship and a higher performance fatigability of the quadriceps muscle. It is recommended that the rehabilitation includes strengthening and fatiguing exercises at maximal and submaximal force levels.

  13. Exercise testing in Warmblood sport horses under field conditions

    NARCIS (Netherlands)

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

    2014-01-01

    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

  14. Effect of music on submaximal cycling

    African Journals Online (AJOL)

    Boutcher SH, Trenske M. The effects of sensory deprivation and music on perceived exertion and affect during exercise. Journal of Sport and Exercise. Psychology 1990; 12: 167-76. 4. Grant S, Aitchison T, Henderson E, et al. A comparison of the reproduc- ibility and the sensitivity to change of visual analogue scales, Borg ...

  15. Low dose of dichloroacetate infusion reduces blood lactate after submaximal exercise in horses Baixa dose de infusão de dicloroacetato reduz o lactato sanguíneo após exercício submáximo em cavalos

    Directory of Open Access Journals (Sweden)

    Guilherme C. Ferraz

    2013-01-01

    Full Text Available The acute administration of an indirect activator of the enzyme pyruvate dehydrogenase (PDH in human athletes causes a reduction in blood lactate level during and after exercise. A single IV dose (2.5m.kg-1 of dichloroacetate (DCA was administered before a submaximal incremental exercise test (IET with five velocity steps, from 5.0 m.s-1 for 1 min to 6.0, 6.5, 7.0 and 7.5m.s-1 every 30s in four untrained mares. The blood collections were done in the period after exercise, at times 1, 3, 5, 10, 15 and 20 min. Blood lactate and glucose (mM were determined electro-enzymatically utilizing a YSI 2300 automated analyzer. There was a 15.3% decrease in mean total blood lactate determined from the values obtained at all assessment times in both trials after the exercise. There was a decrease in blood lactate 1, 3, 5, 10, 15 and 20 min after exercise for the mares that received prior DCA treatment, with respective mean values of 6.31±0.90 vs 5.81±0.50, 6.45±1.19 vs 5.58±1.06, 6.07±1.56 vs 5.26±1.12, 4.88±1.61 vs 3.95±1.00, 3.66±1.41 vs 2.86±0.75 and 2.75±0.51 vs 2.04±0.30. There was no difference in glucose concentrations. By means of linear regression analysis, V140, V160, V180 and V200 were determined (velocity at which the rate heart is 140, 160, 180, and 200 beats/minute, respectively. The velocities related to heart rate did not differ, indicating that there was no ergogenic effect, but prior administration of a relatively low dose of DCA in mares reduced lactatemia after an IET.A administração aguda de um ativador indireto da enzima piruvato desidrogenase (PD em atletas da espécie humana provoca redução na concentração de lactato sanguíneo durante e após exercício. Uma dose única, intravenosa de 2.5m.kg-1 de dicloroacetato (DCA foi administrada antes de um exercício teste incremental submáximo (ETI com cinco etapas de velocidade sendo 5,0 ms-1 por 1 minuto e 6,0, 6,5, 7,0, e 7,5 ms-1 a cada 30 segundos em quatro

  16. Small Combat Arms Unit Leader Training Techniques: Rules of Play for Infantry Field Opposition Exercise

    Science.gov (United States)

    1979-01-01

    Opposition Exercise) originally represented a translation of the EFFTRAIN TOX - Tactical Opposition (Infantry Map Game) Exercise - to a field environment...symbols and grid tick marks). lie first plots the impact location per grid coordinate or registration adjustment request. He than translates the...understanding of those risks andt a knowlodge of what has boon success- ful (or unsuccessful) In similar situations. 46 ANNEX A MINIMUM FOX

  17. A Student Run Field Exercise in Applied Tourism Geography

    Science.gov (United States)

    De Bres, Karen; Coomansingh, Johnny

    2006-01-01

    The purpose of this paper is to discuss the field project and the field experiences of 60 undergraduates in a lower level geography course. Cumulative based learning was the main teaching technique. The Eisenhower Center, the Dickinson County Historical Society Museum, and Old Abilene Town, a renovated/reconstructed frontier town, were selected…

  18. Effect of oxygen on postoperative cardiovascular response to exercise

    DEFF Research Database (Denmark)

    Kjaersgaard, M; Lie, C; Bisgaard, T

    2000-01-01

    OBJECTIVE: To evaluate the effect of supplemental oxygen on postoperative cardiovascular response to submaximal exercise. DESIGN: Randomised, controlled study. SETTING: University hospital, Denmark. SUBJECTS: 16 patients having major abdominal operations. INTERVENTIONS: A submaximal exercise test...... in non-surgical patients and surgical patients not taking exercise. These findings do not suggest that decreased peripheral tissue oxygenation is responsible for the impaired cardiovascular response to exercise in postoperative patients....... oximeter. MAIN OUTCOME MEASURES: Heart rate during exercise. RESULTS: At similar workloads there were significantly lower heart rates (median decrease 3 min(-1)) during exercise tests with oxygen compared with air (p

  19. Inductive plethysmography potential as a surrogate for ventilatory measurements during rest and moderate physical exercise

    Directory of Open Access Journals (Sweden)

    Ramona Cabiddu

    2016-01-01

    Full Text Available Background: Portable respiratory inductive plethysmography (RIP systems have been validated for ventilatory assessment during resting conditions and during incremental treadmill exercise. However, in clinical settings and during field-based exercise, intensity is usually constant and submaximal. A demonstration of the ability of RIP to detect respiratory measurements accurately during constant intensity conditions would promote and validate the routine use of portable RIP devices as an alternative to ergospirometry (ES, the current gold standard technique for ventilatory measures. Objective: To investigate the agreement between respiratory variables recorded by a portable RIP device and by ES during rest and constant intensity exercise. Method: Tidal volume (VT, respiratory rate (RR and minute ventilation (VE were concurrently acquired by portable RIP and ES in seven healthy male volunteers during standing rest position and constant intensity treadmill exercise. Results: Significant agreement was found between RIP and ES acquisitions during the standing rest position and constant intensity treadmill exercise for RR and during the standing rest position for VE. Conclusion: Our results suggest that portable RIP devices might represent a suitable alternative to ES during rest and during constant submaximal exercise.

  20. Prediction of Maximum Oxygen Uptake Using Both Exercise and Non-Exercise Data

    Science.gov (United States)

    George, James D.; Paul, Samantha L.; Hyde, Annette; Bradshaw, Danielle I.; Vehrs, Pat R.; Hager, Ronald L.; Yanowitz, Frank G.

    2009-01-01

    This study sought to develop a regression model to predict maximal oxygen uptake (VO[subscript 2max]) based on submaximal treadmill exercise (EX) and non-exercise (N-EX) data involving 116 participants, ages 18-65 years. The EX data included the participants' self-selected treadmill speed (at a level grade) when exercise heart rate first reached…

  1. Effects of submaximal and supramaximal interval training on determinants of endurance performance in endurance athletes.

    Science.gov (United States)

    Paquette, M; Le Blanc, O; Lucas, S J E; Thibault, G; Bailey, D M; Brassard, P

    2017-03-01

    We compared the effects of submaximal and supramaximal cycling interval training on determinants of exercise performance in moderately endurance-trained men. Maximal oxygen consumption (VO2max ), peak power output (Ppeak ), and peak and mean anaerobic power were measured before and after 6 weeks (3 sessions/week) of submaximal (85% maximal aerobic power [MP], HIIT85 , n = 8) or supramaximal (115% MP, HIIT115 , n = 9) interval training to exhaustion in moderately endurance-trained men. High-intensity training volume was 47% lower in HIIT115 vs HIIT85 (304 ± 77 vs 571 ± 200 min; P training was generally associated with increased VO2max (HIIT85 : +3.3 ± 3.1 mL/kg/min; HIIT115 : +3.3 ± 3.6 ml/kg/min; Time effect P = 0.002; Group effect: P = 0.95), Ppeak (HIIT85 : +18 ± 9 W; HIIT115 : +16 ± 27 W; Time effect P = 0.045; Group effect: P = 0.49), and mean anaerobic power (HIIT85 : +0.42 ± 0.69 W/kg; HIIT115 : +0.55 ± 0.65 W/kg; Time effect P = 0.01; Group effect: P = 0.18). Six weeks of submaximal and supramaximal interval training performed to exhaustion seems to equally improve VO2max and anaerobic power in endurance-trained men, despite half the accumulated time spent at the target intensity. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. F-door spaces and F-submaximal spaces

    Directory of Open Access Journals (Sweden)

    Lobna Dridi

    2013-04-01

    Full Text Available Submaximal spaces and door spaces play an enigmatic role in topology. In this paper, reinforcing this role, we are concerned with reaching two main goals: The first one is to characterize topological spaces X such that F(X is a submaximal space (resp., door space for some covariant functor Ff rom the category Top to itself. T0, and FH functors are completely studied. Secondly, our interest is directed towards the characterization of maps f given by a flow (X, f in the category Set, such that (X,P(f is submaximal (resp., door where P(f is a topology on X whose closed sets are exactly the f-invariant sets.

  3. The validity of submaximal ratings of perceived exertion to predict one repetition maximum.

    Science.gov (United States)

    Eston, Roger; Evans, Harrison James Llewelyn

    2009-01-01

    The One Repetition Maximum (1-RM) test is commonly used to assess strength. However, direct assessments of 1-RM are time consuming and unsafe for novice lifters. Whilst various equations exist to predict 1-RM, there is limited research on the validity of these equations. The purpose of this study was to assess the validity of using sub-maximal ratings of perceived exertion (RPE) to predict 1-RM in young adults, using the Borg 6-20 RPE Scale. Twenty healthy participants (ten male (Mean ± SD, 20.8 ± 0.6 y, 75.7 ± 9.3 kg, 1.8 ± 0.07 m) and ten female (20.3 ± 0.7 y, 68.4 ± 10.0 kg, 1.68 ± 0.03 m)) completed two trials involving resistance exercises for both the upper and lower body. In the first trial the 1-RM for the bilateral biceps curl (BC) and the bilateral knee extension (KE) were determined for each participant. In the second trial, participants performed blinded repetitions which were equivalent to 20, 40 and 60 % of 1-RM for both exercises. The RPE was recorded immediately after two repetitions had been completed at each intensity. The order of intensity of the repetitions was randomly assigned with participants wearing blindfolds to exclude the possibility of pre-determined judgments about load and RPE. Individual RPE recorded at each intensity was subjected to linear regression analysis and the line of best fit was extrapolated to RPE 20 to predict 1-RM in both exercises. There was no significant difference (p > 0.05) between the 1-RM predicted from RPE 20 and measured 1-RM for both exercises for the men and women. Measured and predicted values for men were 46.0 ± 4.6 and 45.2 ± 6. 1 kg for biceps curl, and 46.3 ± 3.8 and 43.0 ± 7.1 kg for knee extension, respectively. Measured and predicted values for women were 18.6 ± 5.7 and 19.3 ± 5.6 kg for biceps curl, and 25.5 ± 9.6 and 27.2 ± 12.6 kg for knee extension, respectively. Pearson product-moment correlation coefficients between actual and predicted 1-RM for the BC and KE were 0.97 and 0

  4. Exercise

    Science.gov (United States)

    ... it can lead to weakness of muscles, decreased bone density with an increased risk of fracture, and shallow, inefficient breathing. An exercise program needs to fit the capabilities and limitations ...

  5. Submaximal cardiopulmonary thresholds on a robotics-assisted tilt table, a cycle and a treadmill: a comparative analysis.

    Science.gov (United States)

    Saengsuwan, Jittima; Nef, Tobias; Laubacher, Marco; Hunt, Kenneth J

    2015-11-10

    The robotics-assisted tilt table (RATT), including actuators for tilting and cyclical leg movement, is used for rehabilitation of severely disabled neurological patients. Following further engineering development of the system, i.e. the addition of force sensors and visual bio-feedback, patients can actively participate in exercise testing and training on the device. Peak cardiopulmonary performance parameters were previously investigated, but it also important to compare submaximal parameters with standard devices. The aim of this study was to evaluate the feasibility of the RATT for estimation of submaximal exercise thresholds by comparison with a cycle ergometer and a treadmill. 17 healthy subjects randomly performed six maximal individualized incremental exercise tests, with two tests on each of the three exercise modalities. The ventilatory anaerobic threshold (VAT) and respiratory compensation point (RCP) were determined from breath-by-breath data. VAT and RCP on the RATT were lower than the cycle ergometer and the treadmill: oxygen uptake (V'O2) at VAT was [mean (SD)] 1.2 (0.3), 1.5 (0.4) and 1.6 (0.5) L/min, respectively (p < 0.001); V'O2 at RCP was 1.7 (0.4), 2.3 (0.8) and 2.6 (0.9) L/min, respectively (p = 0.001). High correlations for VAT and RCP were found between the RATT vs the cycle ergometer and RATT vs the treadmill (R on the range 0.69-0.80). VAT and RCP demonstrated excellent test-retest reliability for all three devices (ICC from 0.81 to 0.98). Mean differences between the test and retest values on each device were close to zero. The ventilatory equivalent for O2 at VAT for the RATT and cycle ergometer were similar and both were higher than the treadmill. The ventilatory equivalent for CO2 at RCP was similar for all devices. Ventilatory equivalent parameters demonstrated fair-to-excellent reliability and repeatability. It is feasible to use the RATT for estimation of submaximal exercise thresholds: VAT and RCP on the RATT were lower than the

  6. Differential contributions of ankle plantarflexors during submaximal isometric muscle action

    DEFF Research Database (Denmark)

    Masood, Tahir; Bojsen-Møller, Jens; Kalliokoski, Kari K

    2014-01-01

    The objective of this study was to investigate the relative contributions of superficial and deep ankle plantarflexors during repetitive submaximal isometric contractions using surface electromyography (SEMG) and positron emission tomography (PET). Myoelectric signals were obtained from twelve....... The findings of this study provide valuable reference for studies where individual muscle contributions are estimated using models and simulations....

  7. An Investigation into Submaximal Endurance in Children with Motor ...

    African Journals Online (AJOL)

    This study investigated the submaximal endurance levels of children with motor difficulties, using the six-minute walk test (6MWT). A prospective, cross-sectional study was conducted. Forty-eight children between ages seven and ten years were enrolled. They came from similar socio-economic backgrounds and attended ...

  8. Exercise

    DEFF Research Database (Denmark)

    Idorn, Manja; thor Straten, Eivind Per

    2016-01-01

    We recently demonstrated that voluntary exercise leads to an influx of immune cells in tumors and a greater than 60% reduction in tumor incidence and growth across several mouse models. Improved immunological control of tumor progression may have important clinical implications in the prevention...... and treatment of cancer in humans....

  9. Statistical Shape Modelling and Markov Random Field Restoration (invited tutorial and exercise)

    DEFF Research Database (Denmark)

    Hilger, Klaus Baggesen

    This tutorial focuses on statistical shape analysis using point distribution models (PDM) which is widely used in modelling biological shape variability over a set of annotated training data. Furthermore, Active Shape Models (ASM) and Active Appearance Models (AAM) are based on PDMs and have proven...... themselves a generic holistic tool in various segmentation and simulation studies. Finding a basis of homologous points is a fundamental issue in PDMs which effects both alignment and decomposition of the training data, and may be aided by Markov Random Field Restoration (MRF) of the correspondence...... deformation field between shapes. The tutorial demonstrates both generative active shape and appearance models, and MRF restoration on 3D polygonized surfaces. ''Exercise: Spectral-Spatial classification of multivariate images'' From annotated training data this exercise applies spatial image restoration...

  10. Effects of Submaximal Endurance Training and Vitamin D3 Supplementation on Pain Threshold in Diabetic Rats

    Directory of Open Access Journals (Sweden)

    S. Jalal Taherabadi

    2013-07-01

    Full Text Available Background: According to beneficial effects of endurance training and vitamin D3 in diabetes mellitus, purpose of this study is effects submaximal endurance training and vitamin D3 supplementation on pain threshold in streptozotocin induced diabetic rats.Materials and Methods: Male Wistar rats (250±20 g, N=40 were made diabetic by streptozotocin (60 mg/kg, subcutaneously. 72 h after injection diabetes induction was confirmed by tail vein blood glucose concentration (>300 mg/dl. Then animals were divided to five groups: diabetic control (DC, diabetic trained (DT, diabetic -vitamin D (DD, diabetic trained and vitamin D (DTD, and control (C. Animals were submitted to endurance training by treadmill and vitamin D3 treatment (twice aweek, intrapretonally for 4 weeks. 48 h after at the end of exercise and treatment protocol, we used tail-flick to assess the effects of training and vitamin D3 on thermal pain threshold. We used one way ANOVA statistical analysis to compare differences between groups, significance level of p<0.05 was considered.Results: Diabetic induced hyperalgesia were decreased significantly by vitamin D but not 4 weeks endurance exercise training. Concurrent effects of training and vitamin D on thermal pain threshold were not significantly higher than vitamin D effects alone.Conclusion: It is concluded that vitamin D administration given at the time of diabetes induction may be able to restore thermal hyperalgesia. But effects of endurance exercise training needs to more investigation in diabetic rats.

  11. Live high:train low increases muscle buffer capacity and submaximal cycling efficiency.

    Science.gov (United States)

    Gore, C J; Hahn, A G; Aughey, R J; Martin, D T; Ashenden, M J; Clark, S A; Garnham, A P; Roberts, A D; Slater, G J; McKenna, M J

    2001-11-01

    This study investigated whether hypoxic exposure increased muscle buffer capacity (beta(m)) and mechanical efficiency during exercise in male athletes. A control (CON, n=7) and a live high:train low group (LHTL, n=6) trained at near sea level (600 m), with the LHTL group sleeping for 23 nights in simulated moderate altitude (3000 m). Whole body oxygen consumption (VO2) was measured under normoxia before, during and after 23 nights of sleeping in hypoxia, during cycle ergometry comprising 4 x 4-min submaximal stages, 2-min at 5.6 +/- 0.4 W kg(-1), and 2-min 'all-out' to determine total work and VO(2peak). A vastus lateralis muscle biopsy was taken at rest and after a standardized 2-min 5.6 +/- 0.4 W kg(-1) bout, before and after LHTL, and analysed for beta(m) and metabolites. After LHTL, beta(m) was increased (18%, P buffer capacity. Further, reduced VO2 during normoxic exercise after LHTL suggests that improved exercise efficiency is a fundamental adaptation to LHTL.

  12. Stability Ball Sitting versus Chair Sitting During Sub-maximal Arm Ergometry.

    Science.gov (United States)

    Marks, Charles R C; Hylland, Kristina E; Terrell, Jacob

    It was predicted that sitting on a stability ball during arm ergometry would elevate cardiovascular parameters when compared to sitting on a chair and that this would be associated with greater recruitment of trunk and leg skeletal muscles. Open-circuit spirometry, videotaping, blood pressure, heart rate, and EMG were conducted during rest and four minute stages of 15 W, 30 W, and 45 W using a Monark arm ergometer. Twenty-six apparently healthy adults exercised twice, once sitting on a stability ball and the other sitting on a chair (order randomized), with 45 to 60 minutes of rest between. ANOVA for repeated measures and paired-t testing were used for analysis. Oxygen consumption was significantly 10 to 16% higher during exercise while sitting on the stability ball. There were no significant differences between sitting modes for heart rate, SBP, and DBP. Also, resting and exercise rectus femoris and 45 W external oblique EMGs were significantly higher on the stability ball. Finally, the knee was significantly more extended with the feet farther apart and more forward on the stability ball. The stability ball significantly elevates oxygen consumption during sub-maximal arm cranking without significantly increasing heart rate or blood pressure and this is associated with increased thigh muscle activation and lower leg repositioning.

  13. Construct validation of a non-exercise measure of cardiorespiratory fitness in older adults.

    Science.gov (United States)

    Mailey, Emily L; White, Siobhan M; Wójcicki, Thomas R; Szabo, Amanda N; Kramer, Arthur F; McAuley, Edward

    2010-02-08

    Cardiorespiratory fitness (CRF) is associated with a decreased risk of all-cause mortality but is rarely assessed in medical settings due to burdens of time, cost, risk, and resources. The purpose of this study was to test the construct validity of a regression equation developed by Jurca and colleagues (2005) to estimate CRF without exercise testing in community dwelling older adults. Participants (n = 172) aged 60 to 80 years with no contraindications to submaximal or maximal exercise testing completed a maximal graded exercise test (GXT) and the submaximal Rockport 1-mile walk test on separate occasions. Data included in the regression equation (age, sex, body mass index, resting heart rate, and physical activity) were obtained via measurement or self-report. Participants also reported presence of cardiovascular conditions. The multiple R for the regression equation was .72, p testing (r = 0.67). All three CRF indices were significantly and inversely associated with reporting more cardiovascular conditions. This research provides preliminary evidence that a non-exercise estimate of CRF is at least as valid as field test estimates of CRF and represents a low-risk, low-cost, and expedient method for estimating fitness in older adults.

  14. THE VALIDITY OF SUBMAXIMAL RATINGS OF PERCEIVED EXERTION TO PREDICT ONE REPETITION MAXIMUM

    Directory of Open Access Journals (Sweden)

    Harrison James Llewelyn Evans

    2009-12-01

    Full Text Available The One Repetition Maximum (1-RM test is commonly used to assess strength. However, direct assessments of 1-RM are time consuming and unsafe for novice lifters. Whilst various equations exist to predict 1-RM, there is limited research on the validity of these equations. The purpose of this study was to assess the validity of using sub-maximal ratings of perceived exertion (RPE to predict 1-RM in young adults, using the Borg 6-20 RPE Scale. Twenty healthy participants (ten male (Mean ± SD, 20.8 ± 0.6 y, 75.7 ± 9.3 kg, 1.8 ± 0.07 m and ten female (20.3 ± 0.7 y, 68.4 ± 10.0 kg, 1.68 ± 0.03 m completed two trials involving resistance exercises for both the upper and lower body. In the first trial the 1-RM for the bilateral biceps curl (BC and the bilateral knee extension (KE were determined for each participant. In the second trial, participants performed blinded repetitions which were equivalent to 20, 40 and 60 % of 1-RM for both exercises. The RPE was recorded immediately after two repetitions had been completed at each intensity. The order of intensity of the repetitions was randomly assigned with participants wearing blindfolds to exclude the possibility of pre-determined judgments about load and RPE. Individual RPE recorded at each intensity was subjected to linear regression analysis and the line of best fit was extrapolated to RPE 20 to predict 1-RM in both exercises. There was no significant difference (p > 0.05 between the 1-RM predicted from RPE 20 and measured 1-RM for both exercises for the men and women. Measured and predicted values for men were 46.0 ± 4.6 and 45.2 ± 6. 1 kg for biceps curl, and 46.3 ± 3.8 and 43.0 ± 7.1 kg for knee extension, respectively. Measured and predicted values for women were 18.6 ± 5.7 and 19.3 ± 5.6 kg for biceps curl, and 25.5 ± 9.6 and 27.2 ± 12.6 kg for knee extension, respectively. Pearson product-moment correlation coefficients between actual and predicted 1-RM for the BC and KE were 0

  15. A new submaximal cycle ergometer test for prediction of VO2max.

    Science.gov (United States)

    Ekblom-Bak, E; Björkman, F; Hellenius, M-L; Ekblom, B

    2014-04-01

    Maximal oxygen uptake (VO2max) is an important, independent predictor of cardiovascular health and mortality. Despite this, it is rarely measured in clinical practice. The aim of this study was to create and evaluate a submaximal cycle ergometry test based on change in heart rate (HR) between a lower standard work rate and an individually chosen higher work rate. In a mixed population (n = 143) with regard to sex (55% women), age (21-65 years), and activity status (inactive to highly active), a model included change in HR per unit change in power, sex, and age for the best estimate of VO2max. The association between estimated and observed VO2max for the mixed sample was r = 0.91, standard error of estimate = 0.302 L/min, and mean measured VO2max = 3.23 L/min. The corresponding coefficient of variation was 9.3%, a significantly improved precision compared with one of the most commonly used submaximal exercise tests, the Åstrand test, which in the present study was estimated to be 18.1%. Test-retest reliability analysis over 1 week revealed no mean difference in the estimated VO2max (-0.02 L/min, 95% confidence interval: -0.07-0.03). The new test is low-risk, easily administered, and valid for a wide capacity range, and is therefore suitable in situations as health evaluations in the general population. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Relationships between field performance tests in high-level soccer players

    DEFF Research Database (Denmark)

    Ingebrigtsen, Jørgen; Brochmann, Marit; Castagna, Carlo

    2014-01-01

    In order to reduce athlete testing time, the aim of this study was to investigate the relationship between the Yo-Yo intermittent recovery test level 1 (IR1) and 2 (IR2) test performances, maximal sprinting speed (10, 20 and 35 m), repeated sprint ability (RSA) (7x35 m), and sub-maximal heart rates...... using only one of the Yo-Yo tests and a RSA test, in a general soccer-specific field test protocol. The sub-maximal heart rate measures during Yo-Yo tests are reproducible and may be utilized for frequent, time-efficient and non-exhaustive testing of intermittent exercise capacity of high-level soccer...

  17. Enriched Open Field Facilitates Exercise and Social Interaction in 2 Strains of Guinea Pigs (Cavia porcellus)

    Science.gov (United States)

    Brewer, Jacob S; Bellinger, Seanceray A; Joshi, Prianca; Kleven, Gale A

    2014-01-01

    Current housing guidelines for laboratory rodents include recommendations for enrichment. Working with guinea pigs, we have developed an open-field enrichment paradigm that provides several aspects of this species’ natural environment. These naturalistic aspects include access to increased space for exploration, access to western timothy (Phleum pratense L.) hay, and grouping as a herd to facilitate social interaction. To determine the immediate effect on behavior from access to the enriched environment, female guinea pigs from 2 strains, IAF Hairless and NIH Hartley, were observed in both standard home cages and an open-field enriched environment. Subjects were housed with cagemates in pairs for the home-cage observation and were grouped as a herd when in the open-field arena. Behaviors were videorecorded for 1 h and then scored. Salivary cortisol levels were measured both prior to and immediately after behavioral observations. Analyses revealed higher levels of activity and social interaction in the open-field arena compared with the home cage, with no significant change in salivary cortisol levels. These results suggest that exposure to the open-field environment provide increased opportunities for exercise and social enrichment. Although additional studies are needed to determine long-term effects on experimental outcomes, the open-field configuration holds promise as a laboratory enrichment paradigm for guinea pigs. PMID:25199089

  18. Nuclear forensic field exercise no.1: work performed in support of CRTI project 04-0030TD. Technical memorandum

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, C. [Defence R and D Canada - Ottawa, Ottawa, Ontario (Canada); Hinton, A. [Canadian Nuclear Safety Commission, Ottawa, Ontario (Canada)

    2006-11-15

    DRDC Ottawa is leading a project designed in part to develop protocols for forensic investigators working in a radiologically contaminated environment. As such, a radiological field exercise was held to review current forensic investigator methods and identify problem areas with respect to the collection of evidence from a contaminated crime scene. The Canadian Nuclear Safety Commission (CNSC), DRDC Ottawa, Royal Canadian Mounted Police (RCMP) and the Ottawa Police Service (OPS) CBRN Forensic Investigation Specialists participated in the exercise. This document provides a description of the scenario and the responder actions during the exercise, and gives lessons learned and recommendations that will feed directly into the forensic investigator protocols. (author)

  19. A submaximal test for the assessment of knee extensor endurance capacity.

    Science.gov (United States)

    De Ruiter, Cornelis J; Mallee, Max I P; Leloup, Lara E C; De Haan, Arnold

    2014-02-01

    We aimed to develop an undemanding test for endurance capacity of the knee extensor muscles, which can also be applied to frail participants. We hypothesized 1) that the first objective indications for peripheral fatigue during incremental unilateral repetitive isometric knee extensor contractions could be used to assess a fatigue threshold (FT), 2) that torque at FT would depend on training status, and 3) that this torque could easily be sustained for 30 min. Five trained and five untrained participants performed 5-min bouts of 60 repetitive contractions (3-s on and 2-s off). Torque, set at 25% maximal voluntary contraction (MVC), was increased by 5% MVC in subsequent bouts. The highest torque for which rectified surface EMG remained stable during the bout was defined as the FT. On separate occasions, 30-min bouts were performed at and above the FT to assess sustainable torque. Changes in gas exchange parameters, HR, and RPE were monitored to corroborate FT. At FT (RPE = 5.7 ± 1.7), torque was higher (P MVC) than in untrained participants (30.5% ± 1.8% MVC). Sustainable torque was ∼4% higher than (P MVC, significant increases in rectified surface EMG and V˙O2 were found. During incremental knee extensor contractions, FT could be assessed at a submaximal exercise intensity. FT was higher in trained than in untrained participants and was related to exercise sustainability. With the use of FT, changes in endurance capacity of single muscle groups can potentially also be determined in frail participants for whom exercise performed until exhaustion is unwarranted.

  20. Is energy expenditure taken into account in human sub-maximal jumping? - a simulation study

    NARCIS (Netherlands)

    Vanrenterghem, J.; Bobbert, M.F.; Casius, L.J.R.; de Clercq, D.

    2008-01-01

    This paper presents a simulation study that was conducted to investigate whether the stereotyped motion pattern observed in human sub-maximal jumping can be interpreted from the perspective of energy expenditure. Human sub-maximal vertical countermovement jumps were compared to jumps simulated with

  1. A New Submaximal Rowing Test to Predict 2,000-m Rowing Ergometer Performance

    NARCIS (Netherlands)

    Otter, Ruby T. A.; Brink, Michel S.; Lamberts, Robert P.; Lemmink, Koen A. P. M.

    Otter, RTA, Brink, MS, Lamberts, RP, and Lemmink, KAPM. A new submaximal rowing test to predict 2,000-m rowing ergometer performance. J Strength Cond Res 29(9): 2426-2433, 2015-The purpose of this study was to assess predictive value of a new submaximal rowing test (SmRT) on 2,000-m ergometer rowing

  2. Comparing VO2max determined by using the relation between heart rate and accelerometry with submaximal estimated VO2max.

    Science.gov (United States)

    Tönis, T M; Gorter, K; Vollenbroek-Hutten, M M R; Hermens, H

    2012-08-01

    An exploratory study to identify parameters that can be used for estimating a subject's cardio-respiratory physical fitness level, expressed as VO2max, from a combination of heart rate and 3D accelerometer data. Data were gathered from 41 healthy subjects (23 male, 18 female) aged between 20 and 29 years. The measurement protocol consisted of a sub-maximal single stage treadmill walking test for VO2max estimation followed by a walking test at two different speeds (4 and 5.5 kmh-1) for parameter determination. The relation between measured heart rate and accelerometer output at different walking speeds was used to get an indication of exercise intensity and the corresponding heart rate at that intensity. Regression analysis was performed using general subject measures (age, gender, weight, length, BMI) and intercept and slope of the relation between heart rate and accelerometer output during walking as independent variables to estimate the VO2max. A linear regression model using a combination of the slope and intercept parameters, together with gender revealed the highest percentage of explained variance (R2 = 0.90) and had a standard error of the estimate (SEE) of 2.052 mL O2kg-1min-1 with VO2max. Results are comparable with current commonly used sub-maximal laboratory tests to estimate VO2max. The combination of heart rate and accelerometer data seems promising for ambulant estimation of VO2max-.

  3. Exposure to a combination of heat and hyperoxia during cycling at submaximal intensity does not alter thermoregulatory responses

    Directory of Open Access Journals (Sweden)

    C Zinner

    2016-02-01

    Full Text Available In this study, we tested the hypothesis that breathing hyperoxic air (FinO2 = 0.40 while exercising in a hot environment exerts negative effects on the total tissue level of haemoglobin concentration (tHb; core (Tcore and skin (Tskin temperatures; muscle activity; heart rate; blood concentration of lactate; pH; partial pressure of oxygen (PaO2 and carbon dioxide; arterial oxygen saturation (SaO2; and perceptual responses. Ten well-trained male athletes cycled at submaximal intensity at 21°C or 33°C in randomized order: first for 20 min while breathing normal air (FinO2 = 0.21 and then 10 min with FinO2 = 0.40 (HOX. At both temperatures, SaO2 and PaO2, but not tHb, were increased by HOX. Tskin and perception of exertion and thermal discomfort were higher at 33°C than 21°C (p 0.07. Blood lactate and heart rate were higher at 33°C than 21°C. In conclusion, during 30 min of submaximal cycling at 21°C or 33°C, Tcore, Tskin and Tbody, tHb, muscle activity and ratings of perceived exertion and thermal discomfort were the same under normoxic and hyperoxic conditions. Accordingly, breathing hyperoxic air (FinO2 = 0.40 did not affect thermoregulation under these conditions.

  4. Evaluation of the American College of Sports Medicine submaximal treadmill running test for predicting VO2max.

    Science.gov (United States)

    Marsh, Clare E

    2012-02-01

    The purpose of this study was to assess the validity of the American College of Sports Medicine's (ACSM's) submaximal treadmill running test in predicting VO2max. Twenty-one moderately well-trained men aged 18-34 years performed 1 maximal treadmill test to determine maximal oxygen uptake (M VO2max) and 2 submaximal treadmill tests using 4 stages of continuous submaximal exercise. Estimated VO2max was predicted by extrapolation to age-predicted maximal heart rate (HRmax) and calculated in 2 ways: using data from all submaximal stages between 110 b·min(-1) and 85% HRmax (P VO2max-All), and using data from the last 2 stages only (P VO2max-2). The measured VO2max was overestimated by 3% on average for the group but was not significantly different to predicted VO2max (1-way analysis of variance [ANOVA] p = 0.695; M VO2max = 53.01 ± 5.38; P VO2max-All = 54.27 ± 7.16; P VO2max-2 = 54.99 ± 7.69 ml·kg(-1)·min(-1)), although M VO2max was not overestimated in all the participants--it was underestimated in 30% of observations. Pearson's correlation, standard error of estimate (SEE), and total error (E) between measured and predicted VO2max were r = 0.646, 4.35, 4.08 ml·kg(-1)·min(-1) (P VO2max-All) and r = 0.642, 4.21, 3.98 ml·kg(-1)·min(-1) (P VO2max-2) indicating that the accuracy in prediction (error) was very similar whether using P VO2max-All or P VO2max-2, with up to 70% of the participants predicted scores within 1 SEE (∼4 ml·kg(-1)·min(-1)) of M VO2max. In conclusion, the ACSM equation provides a reasonably good estimation of VO2max with no difference in predictive accuracy between P VO2max-2 and P VO2max-All, and hence, either approach may be equally useful in tracking an individual's aerobic fitness over time. However, if a precise knowledge of VO2max is required, then it is recommended that this be measured directly.

  5. Aging and exercise performance.

    Science.gov (United States)

    Mahler, D A; Cunningham, L N; Curfman, G D

    1986-05-01

    Diverse physiologic changes occur in the oxygen transport system during the aging process. Physical performance and VO2max decline with age, but the changes may be attenuated by exercise training. Increased ventilation is required during exercise in order to compensate for reduced efficiency of gas exchange. Cardiovascular alterations include prolonged duration of myocardial contraction, a slightly reduced left ventricular ejection fraction during exercise, decreased heart rate during both submaximal and maximal exercise, and attenuation of myocardial response to beta-adrenergic stimulation. Cardiac output during exercise can be maintained in the elderly owing to a greater dependence on ventricular filling. Appropriate exercise training leads to enhanced efficiency of the lungs, heart, and skeletal muscles. These physiologic benefits contribute to an increase in functional capacity and an enhanced sense of well-being. Exercise testing is recommended for individuals who have cardiorespiratory symptoms and for those at risk for the development of coronary artery disease. Reasonable goals for an aerobic training program are continuous activity for 30 minutes at a moderate intensity of exertion at least 3 days per week. The intensity of exercise should be based on a prescribed training heart rate. The exercise prescription should be individualized and should incorporate one or more activities for optimal enjoyment and compliance. Opportunities and facilities for indoor exercise are important during inclement weather. Regular physical exercise is important at any age!

  6. The Effect of Two Different Modes of Exercise Swimming and Vitamin C Supplementation on Anemia Indices in Male Wistar Rat

    OpenAIRE

    Fatemeh Lashkari; Mohammad Ali Samavati Sharif; Kamal Ranjbar

    2015-01-01

    Introduction: It has been shown that long term swimming exercise leads to anemia. Therefore the aim of the present study was the effect of vitamin C supplement and maximal and submaximal swimming exercise on anemia in without iron deficiency rats.Methods: For this purpose, 60 male wistar rats (6-8 week age and 170 -190 g weight) were divided into 6 groups: 1: Control rats (Con, n=10) 2: Vitamin C supplementation (Con+C, n=10) 3: Submaximal swimming (S, n=10) 4: Submaximal swimming + Vitamin C...

  7. The effect of maximal vs submaximal exertion on postprandial lipid levels in individuals with and without coronary heart disease.

    Science.gov (United States)

    Aronov, David M; Bubnova, Marina G; Perova, Natalia V; Orekhov, Alexander N; Bobryshev, Yuri V

    Decisions about fat consumption and levels of physical activity are among the everyday choices we make in life and risk of coronary heart disease (CHD) can be affected by those choices. The purpose of this study was to investigate the influence of a standard fat load combined with physical exertion of different intensities on the plasma lipid profile of CHD patients and CHD-free individuals. This study looked at the influence of different intensities of physical exercise on postprandial lipid metabolism in 20 healthy men and 36 men with diagnosis of CHD. Venous blood samples were obtained after overnight fasting, 3 hours after standard fat load (before the physical load), and immediately after maximal or submaximal physical exercise on bicycle ergometer. After fat load total cholesterol (TC) concentration did not change in either group. However, after the addition of maximal exercise, TC, triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and apolipoprotein (Apo) B increased significantly (P < .01) in both groups. After fat load and maximal exercise, there was no change in high-density lipoprotein cholesterol (HDL-C) in healthy men, but in men with CHD, HDL-C fell significantly (P < .01); and Apo AI rose in healthy men (P < .01) but dropped significantly (P < .01) in men with CHD. Submaximal physical exercise (60% of max VO2 load for 40 minutes) after fat load decreased TG level in CHD patients (P < .01) and improved other lipid parameters in both groups significantly (↓LDL-C, ↑HDL-C, ↑Apo AI, ↓Apo B, P < .01). We observed a worsening of physical work capacity in men with CHD (significant reduction of duration and total amount of work performed, maximal VO2, oxygen pulse), during maximal stress test performed 3 hours after fat load. There was a doubling of the number of abnormal stress test results (P < .01). Healthy persons showed an increase in respiratory parameters (ventilation, CO2 production, maximal VO2, and oxygen

  8. Developing new VO2max prediction models from maximal, submaximal and questionnaire variables using support vector machines combined with feature selection.

    Science.gov (United States)

    Abut, Fatih; Akay, Mehmet Fatih; George, James

    2016-12-01

    Maximal oxygen uptake (VO2max) is an essential part of health and physical fitness, and refers to the highest rate of oxygen consumption an individual can attain during exhaustive exercise. In this study, for the first time in the literature, we combine the triple of maximal, submaximal and questionnaire variables to propose new VO2max prediction models using Support Vector Machines (SVM's) combined with the Relief-F feature selector to predict and reveal the distinct predictors of VO2max. For comparison purposes, hybrid models based on double combinations of maximal, submaximal and questionnaire variables have also been developed. By utilizing 10-fold cross-validation, the performance of the models has been calculated using multiple correlation coefficient (R) and root mean square error (RMSE). The results show that the best values of R and RMSE, with 0.94 and 2.92mLkg-1min-1 respectively, have been obtained by combining the triple of relevantly identified maximal, submaximal and questionnaire variables. Compared with the results of the rest of hybrid models in this study and the other prediction models in literature, the reported values of R and RMSE have been found to be considerably more accurate. The predictor variables gender, age, maximal heart rate (MX-HR), submaximal ending speed (SM-ES) of the treadmill and Perceived Functional Ability (Q-PFA) questionnaire have been found to be the most relevant variables in predicting VO2max. The results have also been compared with that of Multilayer Perceptron (MLP) and Tree Boost (TB), and it is seen that SVM significantly outperforms other regression methods for prediction of VO2max. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Exercise Physiology as a specialization within the field of Physical Education: An analysis from the own institutional context

    Directory of Open Access Journals (Sweden)

    Miriam Marracino

    2009-11-01

    Full Text Available The purpose of this paper is to analyze the existence of an apparent contradiction between the ideas and beliefs that guide our institution's academic activity, the Department of Physical Education,from the Faculty of Humanities and Education Ciences at La Plata National University, and the implementation of the "Exercise Physiology Specialization", a graduate career in the field of Physical Education

  10. Evaluation of supplementing active peptide's effect on recovering skeletal muscle micro-injury after track and field exercises.

    Science.gov (United States)

    Li, Caifeng; Yang, Zongyou

    2017-01-01

    To explore the effect of supplementing active peptide on recovering skeletal muscle injury after track and field exercises. choose 80 patients (contain teenagers) with skeletal muscle micro-injury after the track and field exercises from March 2015 to July 2016, divide them into two groups. Normal treatment of micro-injury of skeletal muscle is given to the control group while active peptide is supplemented to the experimental group based on normal treatment. Compare the two groups to find the differences in relevant indexes of skeletal muscle after track and field exercises. Patients with micro-injury of skeletal muscle after track and field exercises may have inflammation at the early stage, so they need a long time for recovery. Relevant indexes of the experimental group after the treatment of supplementing active peptide are better than those of the control group (Pinjury on skeletal muscle and reduce the extravasations of creatine kinase in the cell, so as to improve the patients' anti-fatigue ability and endurance level.

  11. Reliability and Seasonal Changes of Submaximal Variables to Evaluate Professional Cyclists.

    Science.gov (United States)

    Rodríguez-Marroyo, Jose A; Pernía, Raúl; Villa, José G; Foster, Carl

    2017-11-01

    The aim of this study was to determine the reliability and validity of several submaximal variables that can be easily obtained by monitoring cyclists' performances. Eighteen professional cyclists participated in this study. In a first part (n = 15) the test-retest reliability of heart rate (HR) and rating of perceived exertion (RPE) during a progressive maximal test was measured. Derived submaximal variables based on HR, RPE, and power output (PO) responses were analyzed. In a second part (n = 7) the pattern of the submaximal variables according to cyclists' training status was analyzed. Cyclists were assessed 3 times during the season: at the beginning of the season, before the Vuelta a España, and the day after this Grand Tour. Part 1: No significant differences in maximal and submaximal variables between test-retest were found. Excellent ICCs (0.81-0.98) were obtained in all variables. Part 2: The HR and RPE showed a rightward shift from early to peak season. In addition, RPE showed a left shift after the Vuelta a España. Submaximal variables based on RPE had the best relationship with both performance and changes in performance. The present study showed the reliability of different maximal and submaximal variables used to assess cyclists' performances. Submaximal variables based on RPE seem to be the best to monitor changes in training status over a season.

  12. A Systematic Review of Submaximal Cycle Tests to Predict, Monitor, and Optimize Cycling Performance.

    Science.gov (United States)

    Capostagno, Benoit; Lambert, Michael I; Lamberts, Robert P

    2016-09-01

    Finding the optimal balance between high training loads and recovery is a constant challenge for cyclists and their coaches. Monitoring improvements in performance and levels of fatigue is recommended to correctly adjust training to ensure optimal adaptation. However, many performance tests require a maximal or exhaustive effort, which reduces their real-world application. The purpose of this review was to investigate the development and use of submaximal cycling tests that can be used to predict and monitor cycling performance and training status. Twelve studies met the inclusion criteria, and 3 separate submaximal cycling tests were identified from within those 12. Submaximal variables including gross mechanical efficiency, oxygen uptake (VO2), heart rate, lactate, predicted time to exhaustion (pTE), rating of perceived exertion (RPE), power output, and heart-rate recovery (HRR) were the components of the 3 tests. pTE, submaximal power output, RPE, and HRR appear to have the most value for monitoring improvements in performance and indicate a state of fatigue. This literature review shows that several submaximal cycle tests have been developed over the last decade with the aim to predict, monitor, and optimize cycling performance. To be able to conduct a submaximal test on a regular basis, the test needs to be short in duration and as noninvasive as possible. In addition, a test should capture multiple variables and use multivariate analyses to interpret the submaximal outcomes correctly and alter training prescription if needed.

  13. Influence of dynamic versus static core exercises on performance in field based fitness tests.

    Science.gov (United States)

    Parkhouse, Kelly L; Ball, Nick

    2011-10-01

    Minimal evidence supports the claim that core stability training transfers into improved performance and the most effective training method to perform core exercises is still unknown. The purpose of the study was to compare the effects of a 6 week unstable static versus unstable dynamic core training program, on field based fitness tests. A static (n = 6) and dynamic (n = 6) training group performed two 45 min sessions per week for six weeks. Seven performance tests, consisting of three core (plank; double leg lowering; back extensions), one static (standing stork) and three dynamic (overhead medicine ball throw; vertical jump; 20 m sprint), were administered pre- and post training. Between group differences were assessed using a repeated measures MANOVA (P core tests (P  0.05). Findings indicate that both types of training improved specific measures of core stability but did not transfer into any sport-related skill. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  14. Inflight Exercise Regimen for the 2-Hour Prebreathe Protocol

    Science.gov (United States)

    Foster, Philip P.; Gernhardt, Michael L.; Woodruff, Kristin K.; Schneider, Susan M.; Homick, Jerry L. (Technical Monitor)

    2000-01-01

    A 10 min aerobic prebreathe exercise up to 75% V-O2(sub max) on a dual-cycle ergometer, included in the 2-hour prebreathe protocol, has been shown to dramatically reduce the incidence of decompression sickness (DCS) at altitude. In-flight only leg ergometry will be available. A balanced exercise was developed using surgical tubing with the ergometer on-orbit. We hypothesize that a 75% V02max workload, individually prescribed, would be achieved using a target heart rate to regulate the intensity of the arm exercise. VO2, heart rate (HR) / ECG, V-CO2 /V-O2, V(sub E), and V(sub T), and rate of perceived exertion (Borg scale) were measured in eleven healthy subjects who passed a US Air Force Class III Physical examination. A V-O2 peak test was performed to assess the sub-maximal exercise prescription. Two series of sub-maximal tests were performed: (1) leg ergometer/hand ergometer and (2) leg ergometer/surgical tubes. We found no significant differences (P > 0.05) in comparing the means for V-O2 and HR between the predicted and measured values during the final 4 minute-stage at "75% V-O2 workload" or between the two types of sub-maximal tests. The prescribed prebreathe sub-maximal exercise performed with flight certified surgical tubes was achieved using the target HR.

  15. Validated Predictions of Metabolic Energy Consumption for Submaximal Effort Movement.

    Directory of Open Access Journals (Sweden)

    George A Tsianos

    2016-06-01

    Full Text Available Physical performance emerges from complex interactions among many physiological systems that are largely driven by the metabolic energy demanded. Quantifying metabolic demand is an essential step for revealing the many mechanisms of physical performance decrement, but accurate predictive models do not exist. The goal of this study was to investigate if a recently developed model of muscle energetics and force could be extended to reproduce the kinematics, kinetics, and metabolic demand of submaximal effort movement. Upright dynamic knee extension against various levels of ergometer load was simulated. Task energetics were estimated by combining the model of muscle contraction with validated models of lower limb musculotendon paths and segment dynamics. A genetic algorithm was used to compute the muscle excitations that reproduced the movement with the lowest energetic cost, which was determined to be an appropriate criterion for this task. Model predictions of oxygen uptake rate (VO2 were well within experimental variability for the range over which the model parameters were confidently known. The model's accurate estimates of metabolic demand make it useful for assessing the likelihood and severity of physical performance decrement for a given task as well as investigating underlying physiologic mechanisms.

  16. Effects of menstrual phase and amenorrhea on exercise performance in runners.

    Science.gov (United States)

    De Souza, M J; Maguire, M S; Rubin, K R; Maresh, C M

    1990-10-01

    There are few well controlled studies in terms of subject selection, menstrual classification, and exercise protocol that have examined both maximal and submaximal exercise responses during different phases of the menstrual cycle in eumenorrheic runners and compared these runners to amenorrheic runners. Thus, the purpose of this study was to measure selected physiological and metabolic responses to maximal and submaximal exercise during two phases of the menstrual cycle in eumenorrheic runners and amenorrheic runners. Eight eumenorrheic runners (29.0 +/- 4.2 yr) and eight amenorrheic runners (24.5 +/- 5.7 yr) matched for physical, gynecological, and training characteristics were studied. The eumenorrheic runners performed one maximal and one submaximal (40 min at 80% VO2max) treadmill run during both the early follicular (days 2-4) and midluteal (6-8 d from LH surge) phases. The amenorrheic runners performed one maximal and one submaximal (40 min at 80% VO2max) treadmill run. Cycle phases were documented by urinary luteinizing hormone and progesterone assays and by plasma estradiol and progesterone assays. No differences were observed in oxygen uptake, minute ventilation, heart rate, respiratory exchange ratio, rating of perceived exertion, time to fatigue (maximal), and plasma lactate (following the maximal and submaximal exercise tests) between the follicular and luteal phases in the eumenorrheic runners and the amenorrheic runners. We conclude that neither menstrual phase (follicular vs luteal) nor menstrual status (eumenorrheic vs amenorrheic) alters or limits exercise performance in female athletes.

  17. Acute Warm-up Effects in Submaximal Athletes: An EMG Study of Skilled Violinists.

    Science.gov (United States)

    McCrary, J Matt; Halaki, Mark; Sorkin, Evgeny; Ackermann, Bronwen J

    2016-02-01

    Warm-up is commonly recommended for injury prevention and performance enhancement across all activities, yet this recommendation is not supported by evidence for repetitive submaximal activities such as instrumental music performance. The objective of this study is to quantify the effects of cardiovascular, core muscle, and musical warm-ups on muscle activity levels, musical performance, and subjective experience in skilled violinists. Fifty-five undergraduate, postgraduate, or professional violinists performed five randomly ordered 45-s musical excerpts of varying physical demands both before and after a randomly assigned 15-min, moderate-intensity cardiovascular, core muscle, musical (technical violin exercises), or inactive control warm-up protocol. Surface EMG data were obtained for 16 muscles of the trunk, shoulders, and right arm during each musical performance. Sound recording and perceived exertion (RPE) data were also obtained. Sound recordings were randomly ordered and rated for performance quality by blinded adjudicators. Questionnaire data regarding participant pain sites and fitness levels were used to stratify participants according to pain and fitness levels. Data were analyzed using two- and three-factor ANCOVA (surface EMG and sound recording) and Wilcoxon matched pairs tests (RPE). None of the three warm-up protocols had significant effects on muscle activity levels (P ≥ 0.10). Performance quality did not significantly increase (P ≥ 0.21). RPE significantly decreased (P 0.23). Acute physiological and musical benefits from cardiovascular, core muscle, and musical warm-ups in skilled violinists are limited to decreases in RPE. This investigation provides data from the performing arts in support of sports medical evidence suggesting that warm-up only effectively enhances maximal strength and power performance.

  18. Dissociation between lactate and proton exchange in muscle during intense exercise in man

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Juel, Carsten; Hellsten, Ylva

    1997-01-01

    , the difference between net proton and lactate release was positive throughout exercise and of similar magnitude in N and H. 5. The present data suggest that (1) H+ exchange in muscle during submaximal exercise can to a large extent occur through mechanisms other than via coupling to lactate; (2) muscle transport...

  19. Ethnic differences in vascular responses to aerobic exercise.

    Science.gov (United States)

    Foulds, Heather J A; Bredin, Shannon S D; Warburton, Darren E R

    2015-02-01

    Indigenous populations currently experience greater rates of cardiovascular disease. Although ethnic differences in cardiovascular responses to exercise have previously been identified, these responses among indigenous populations are unknown. This investigation aimed to evaluate the vascular responses to aerobic exercise of Canadian indigenous and European adults. Twelve age- and sex-matched indigenous and European adults completed a cycle ergometer maximal aerobic power test and submaximal 30 min of 60% maximal aerobic capacity on two separate days. Blood pressure, pulse wave velocity, baroreceptor sensitivity, arterial compliance, vascular resistance, and intima-media thickness were directly measured before and after aerobic exercises. Vascular responses to exercise were generally similar between indigenous and European adults including decreases in baroreceptor sensitivity and vascular resistance after maximal exercise. No changes in intima-media thickness, pulse wave velocity, and arterial compliance were observed after exercise in either group. However, after submaximal exercise, only European adults demonstrated reductions in baroreceptor sensitivity (spectral: 9.2 ± 4.3 to 11.5 ± 6.7 ms·mm Hg, P = 0.41, vs 15.8 ± 8.3 m·s to 8.9 ± 5.7 ms·mm Hg, P = 0.02; sequence: 14.6 ± 5.4 to 16.5 ± 11.0 ms·mm Hg, P = 0.48, vs 26.2 ± 10.5 m·s to 15.4 ± 9.4 ms·mm Hg, P = 0.02). Similarly, decreases in blood pressure after exercise were observed only among European adults. Indigenous adults demonstrated vascular responses similar to those demonstrated by European adults, although blood pressure was only observed to decrease among European adults after maximal and submaximal exercise, and baroreceptor sensitivity, after submaximal exercise.

  20. Exercise performance, core temperature, and metabolism after prolonged restricted activity and retraining in dogs

    Science.gov (United States)

    Nazar, K.; Greenleaf, J. E.; Pohoska, E.; Turlejska, E.; Kaciuba-Uscilko, H.; Kozlowski, S.

    1992-01-01

    Physiological effects of restricted activity (RA) and subsequent retraining have been studied. Ten male mongrel dogs performed a submaximal exercise endurance test on a treadmill during kennel control, after 8 weeks of cage confinement and after eight weeks of retraining using the same treadmill protocol 1 h/d for 6 d/week. Data obtained show that RA reduces exercise endurance, the effectiveness of exercise thermoregulation, muscle glycogen stores, and the lipolytic response to exercise and to noradrenaline stimulation.

  1. Actual Versus Predicted Cardiovascular Demands in Submaximal Cycle Ergometer Testing.

    Science.gov (United States)

    Hoehn, Amanda M; Mullenbach, Megan J; Fountaine, Charles J

    The Astrand-Rhyming cycle ergometer test (ARCET) is a commonly administered submaximal test for estimating aerobic capacity. Whereas typically utilized in clinical populations, the validity of the ARCET to predict VO 2max in a non-clinical population, especially female, is less clear. Therefore, the purpose of this study was to determine the accuracy of the ARCET in a sample of healthy and physically active college students. Subjects (13 females, 10 males) performed a maximal cycle ergometer test to volitional exhaustion to determine VO 2max . At least 48 hours later, subjects performed the ARCET protocol. Predicted VO 2max was calculated following the ARCET format using the age corrected factor. There was no significant difference (p=.045) between actual (41.0±7.97 ml/kg/min) and predicted VO 2max (40.3±7.58 ml/kg/min). When split for gender there was a significant difference between actual and predicted VO 2 for males, (45.1±7.74 vs. 42.7±8.26 ml/kg/min, p=0.029) but no significant difference observed for females, (37.9±6.9 vs. 38.5±6.77 ml/kg/min, p=0.675). The correlation between actual and predicted VO 2 was r=0.84, phealthy college population of both male and female subjects. Implications of this study suggest the ARCET can be used to assess aerobic capacity in both fitness and clinical settings where measurement via open-circuit spirometry is either unavailable or impractical.

  2. Effects of music during exercise on RPE, heart rate and the autonomic nervous system.

    Science.gov (United States)

    Yamashita, S; Iwai, K; Akimoto, T; Sugawara, J; Kono, I

    2006-09-01

    The purpose of this study was to investigate the relationship between the influence of music on RPE during sub-maximal exercise and on the autonomic nervous system before and after sub-maximal exercise. Heart rate (HR), HR variability (HRV) and rates of physical fatigue (RPE) during exercise at 60% and at 40% VO2max with and without music were measured. The exercise protocol consisted of a 30-min seated rest (control) period followed by a 30-min submaximal cycling exercise and a 35-min recovery period. Autonomic-nervous activity was measured before and after exercise. During exercise, RPE was recorded every 3 min and HR was recorded for every minute. Although RPE did not differ during exercise at 60% VO2max, this value was lower during exercise at 40% VO2max in the presence, than in the absence of a favorite piece music (P music. These findings suggested that music evokes a ''distraction effect'' during low intensity exercise, but might not influence the autonomic nervous system. Therefore, when jogging or walking at comparatively low exercise intensity, listening to a favorite piece of music might decrease the influence of stress caused by fatigue, thus increasing the ''comfort'' level of performing the exercise.

  3. Warfighter Physiological Status Monitoring (WPSM): Energy Balance and Thermal Status During a 10-Day Cold Weather U.S. Marine Corps Infantry Officer Course Field Exercise

    National Research Council Canada - National Science Library

    Hoyt, Reed

    2001-01-01

    ...) during a 10-day field exercise (FEX) at Quantico, VA. Question: Does intense physical activity, limited sleep, and restricted rations, combined with cold/damp weather, result in excessively negative energy balance and hypothermia? Methods...

  4. Hemodynamic responses to single sessions of aerobic exercise and resistance exercise in pregnancy.

    Science.gov (United States)

    Petrov Fieril, Karolina; Glantz, Anna; Fagevik Olsen, Monika

    2016-09-01

    Previous research on maternal hemodynamic responses to a single exercise session during pregnancy is sparse, especially considering immediate responses to resistance exercise. The aim of the study was to examine blood pressure, heart rate, body temperature, and Rating of Perceived Exertion in healthy pregnant women during single sessions of continuous submaximal exercise in pregnancy week 21. A cross-over design was used. Twenty healthy pregnant women from four prenatal clinics in Gothenburg, Sweden, were included. On day 1, the women did 30 min of aerobic exercise and on day 3 they did 30 min of resistance exercise. Blood pressure, heart rate, and Rating of Perceived Exertion were measured after 15 and 30 min of exercise. After 15 and 30 min of exercise, there was a significant increase in systolic blood pressure and heart rate (p exercise (p = 0.01) than resistance exercise (p = 0.03). Resistance exercise was perceived as more intense than aerobic exercise after 15 min (p = 0.02) and 30 min (p = 0.001) of exercise. Five minutes after completing the exercise, blood pressure quickly reverted to normal although heart rate was still increased (p = 0.001). There was no correlation between heart rate and Rating of Perceived Exertion (rs  = 0.05-0.43). Maternal hemodynamic responses were essentially the same, regardless of whether the exercise was submaximal aerobic or resistance exercise, although resistance exercise was perceived as more intense. Aerobic and resistance exercise corresponding to "somewhat hard" seems to have no adverse effect with regard to maternal hemodynamic responses in healthy pregnancy. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

  5. Field Botanist for a Day: A Group Exercise for the Introductory Botany Lab

    Science.gov (United States)

    Barbatt, Natalie M.

    2004-01-01

    A group exercise, suggested to be most effective when used near the semester-end, enables entry-level students to appreciate the application of plant biology and makes botany labs experimental. It is believed that this series of labs helps students to appreciate their own learning when they teach and explain things to others.

  6. Uncertainty Exposed: A Field Lab Exercise Where GIS Meets the Real World

    Science.gov (United States)

    Prisley, Stephen P.; Luebbering, Candice

    2011-01-01

    Students in natural resources programs commonly take courses in geospatial technologies. An awareness of the uncertainty of spatial data and algorithms can be an important outcome of such courses. This article describes a laboratory exercise in a graduate geographic information system (GIS) class that involves collection of data for the assessment…

  7. Effect of orthostatic stress on exercise performance after bedrest

    Science.gov (United States)

    Convertino, V. A.; Goldwater, D. J.; Sandler, H.

    1982-01-01

    The cardiorespiratory responses to supine against upright exercise were compared to determine the orthostatic effects of gravity on exercise performance following bedrest. Five healthy male subjects underwent seven days of continuous bedrest. A deconditioning effect was manifested by significant increases in ventilation volume, carbon dioxide production, respiratory exchange ratio, heart rate, heart rate-pressure product, and diastolic blood pressure during submaximal exercise following bedrest. The major finding from this study was that bedrest resulted in a general decrease in exercise tolerance, which was more stressful in the upright posture compared to the supine position, judging from specific submaximal cardiorespiratory responses to cycle ergometry. The data support the hypothesis that there is an orthostatic factor to the reduction in work tolerance following bedrest deconditioning, in addition to the effects caused by increased physical activity.

  8. Effect of music on submaximal cycling | Schie | South African Journal ...

    African Journals Online (AJOL)

    Objective. Athletes frequently report training to music, yet there have been relatively few studies that have addressed the benefit of exercising with music. Design. Volunteer men and women (N=30), aged between 18 and 40 years, performed an initial familiarisation session. Part of this session involved the measurement of ...

  9. Attitudes of Iranian Male University Students Toward Sport and Exercise with Reference to Age, Educational Level, and Field of Study

    Directory of Open Access Journals (Sweden)

    Mirsafian Hamidreza

    2014-12-01

    Full Text Available This article aimed to discover the attitudes of Iranian male university students toward sport and exercise. This study is based on the same research as another published paper regarding the attitudes of Iranian female students toward sport and exercise. Participants (N = 821 were selected from different educational levels and fields of study from among 12 public universities. Data were collected by a modified and developed version of Kenyon's scale (1968, which measures the attitudes of people toward physical activity. For the analysis of the data, independent sample t-test and multivariate analysis of variance (MANOVA were employed (p < 0.05. The results indicated that the attitudes of the respondents can be identified as fitness (3.96 ± 1.02, catharsis (3.84 ± 0.80, social (3.82 ± 1.10, aesthetic (3.03 ± 1.14, vertigo (2.15 ± 1.16, and ascetic (2.07 ± 0.79. Furthermore, it was found that various demographic and social characteristics affected participants' attitudes toward sport and exercise (p < 0.05. Based on the results, it was concluded that the sport programs should be organized around students' dominant attitudes toward regular activities. In addition, planning and organizing sport programs with regard to the wide attitudinal differences between male and female students could be a big step toward improving students' participation rate in sporting activities at Iranian universities.

  10. Cardiovascular responses during a submaximal exercise test in patients with Parkinson's disease.

    NARCIS (Netherlands)

    Speelman, A.D.; Groothuis, J.T.; Nimwegen, M. van; Scheer, E.S. van der; Borm, G.F.; Bloem, B.R.; Hopman, M.T.E.; Munneke, M.

    2012-01-01

    BACKGROUND: Patients with Parkinson's disease (PD) are physically less active than controls, and autonomic dysfunction may contribute to this sedentary lifestyle. Specifically, an altered cardiovascular response to physical effort may restrict physical activities. OBJECTIVE: To assess the

  11. Sex and Exercise Intensity Do Not Influence Oxygen Uptake Kinetics in Submaximal Swimming

    Science.gov (United States)

    Reis, Joana F.; Millet, Gregoire P.; Bruno, Paula M.; Vleck, Veronica; Alves, Francisco B.

    2017-01-01

    The aim of this study was to compare the oxygen uptake (V˙O2) kinetics in front crawl between male and female swimmers at moderate and heavy intensity. We hypothesized that the time constant for the primary phase V˙O2 kinetics was faster in men than in women, for both intensities. Nineteen well trained swimmers (8 females mean ± SD; age 17.9 ± 3.5 years; mass 55.2 ± 3.6 kg; height 1.66 ± 0.05 m and 11 male 21.9 ± 2.8 years; 78.2 ± 11.1 kg; 1.81 ± 0.08 m) performed a discontinuous maximal incremental test and two 600-m square wave transitions for both moderate and heavy intensities to determine the V˙O2 kinetics parameters using mono- and bi-exponential models, respectively. All the tests involved breath-by-breath analysis of front crawl swimming using a swimming snorkel. The maximal oxygen uptake (V˙O2max) was higher in men than in women [4,492 ± 585 ml·min−1 and 57.7 ± 4.4 ml·kg−1·min−1 vs. 2,752.4 ± 187.9 ml·min−1 (p ≤ 0.001) and 50.0 ± 5.7 ml·kg−1·min−1(p = 0.007), respectively]. Similarly, the absolute amplitude of the primary component was higher in men for both intensities (moderate: 1,736 ± 164 vs. 1,121 ± 149 ml·min−1; heavy: 2,948 ± 227 vs. 1,927 ± 243 ml·min−1, p ≤ 0.001, for males and females, respectively). However, the time constant of the primary component (τp) was not influenced by sex (p = 0.527) or swimming intensity (p = 0.804) (moderate: 15.1 ± 5.6 vs. 14.4 ± 5.1 s; heavy: 13.5 ± 3.3 vs. 16.0 ± 4.5 s, for females and males, respectively). The slow component in the heavy domain was not significantly different between female and male swimmers (3.2 ± 2.4 vs. 3.8 ± 1.0 ml·kg−1·min−1, p = 0.476). Overall, only the absolute amplitude of the primary component was higher in men, while the other V˙O2 kinetics parameters were similar between female and male swimmers at both moderate and heavy intensities. The mechanisms underlying these similarities remain unclear. PMID:28239356

  12. Estimation of maximal oxygen uptake via submaximal exercise testing in sports, clinical, and home settings

    NARCIS (Netherlands)

    Sartor, F.; Vernillo, G.; de Morree, H.M.; Bonomi, A.G.; La Torre, A.; Kubis, H.P.; Veicsteinas, A.

    2013-01-01

    Assessment of the functional capacity of the cardiovascular system is essential in sports medicine. For athletes, the maximal oxygen uptake (V˙O2max) provides valuable information about their aerobic power. In the clinical setting, the V˙O2max provides important diagnostic and prognostic information

  13. Within- and Between-Day Repeatability and Variability in Children's Physiological Responses during Submaximal Treadmill Exercise

    Science.gov (United States)

    Amorim, Paulo R. S.; Byrne, Nuala Mary; Hills, Andrew P.

    2009-01-01

    The purpose of this study was to verify within- and between-day repeatability and variability in children's oxygen uptake (VO[subscript 2]), gross economy (GE; VO[subscript 2] divided by speed) and heart rate (HR) during treadmill walking based on self-selected speed (SS). Fourteen children (10.1 plus or minus 1.4 years) undertook three testing…

  14. Description of a standardized rehabilitation program based on sub-maximal eccentric following a platelet-rich plasma infiltration for jumper’s knee

    Science.gov (United States)

    Kaux, Jean-François; Forthomme, Bénédicte; Namurois, Marie-Hélène; Bauvir, Philippe; Defawe, Nathalie; Delvaux, François; Lehance, Cédric; Crielaard, Jean-Michel; Croisier, Jean-Louis

    2014-01-01

    Summary Introduction. Different series emphasized the necessity of rehabilitation program after infiltration of platelet-rich plasma (PRP) in case of tendinopathy. However, most of them describe only briefly the reeducation protocol and these programs vary. Our aim was to extensively describe a specific standardized rehabilitation program. Methods. After a review of literature of post-PRP infiltration protocols, we had developed a standardized rehabilitation protocol. This protocol was evaluated by 30 subjects with chronic jumper’s knee who. A standardised progressive sub-maximal eccentric program supervised by a physical therapist for 6 weeks was started 1 week post-infiltration. The patient benefited also from electromyostimulation, isometric strengthening and stretching of the quadriceps, cycloergometer and cryotherapy. After the supervised program, the patient had to make an auto-reeducation added to the reathletisation protocol for 6 more weeks which was followed by maintenance exercises up to 1 year. The assessments were made using a VAS, IKDC and VISA-P scores. Results. The VAS, IKDC and VISA-P scores decreased very significantly with time. The compliance to auto-reeducation was good. Conclusions. We proposed a simple and efficient protocol based on sub-maximal eccentric reeducation to add to PRP infiltrations in case of patellar tendinopathy. PMID:24932453

  15. Exercise responses during functional electrical stimulation cycling in individuals with spinal cord injury.

    Science.gov (United States)

    Hasnan, Nazirah; Ektas, Nalan; Tanhoffer, Aldre Izabel P; Tanhoffer, Ricardo; Fornusek, Che; Middleton, James W; Husain, Ruby; Davis, Glen M

    2013-06-01

    This study compared acute exercise responses during arm cranking, functional electrical stimulation (FES)-assisted leg cycling, and combined arm and leg ("hybrid") cycling in individuals with spinal cord injury during maximal and submaximal exercise. Nine male subjects with long-standing neurological lesions from C7 to T12 were recruited. All subjects performed arm crank ergometry (ACE), FES leg cycle exercise (FES-LCE), combined ACE + FES-LCE, and cycling on a hybrid FES tricycle (HYBRID). They were assessed for their peak exercise responses in all four modalities. Subsequently, their submaximal heart rates (HR), cardiac outputs (Q), stroke volumes (SV), and arteriovenous oxygen extractions (Ca-Cv)O2 were measured at 40%, 60%, and 80% of mode-specific V˙O2peak. Arm exercise alone and arm + leg exercise resulted in significantly higher V˙O2peak and HRpeak compared with FES-LCE (P spinal cord injury population.

  16. Young and middle-aged women's changes of heart rate during exercise and its connection with Earth's local magnetic field fluctuations.

    OpenAIRE

    Lileikytė, Ingrida

    2017-01-01

    The aim: to determine the heart rate change of women of different ages during exercise and its connection with fluctuation of the Earth‘s magnetic field. Tasks: 1. To determine individual heart rate changes of young and middle-aged women during different phases of aerobic exercise. 2. To assess the heart rate changes of women of different ages during exercise. 3. To determine connections between the heart rate of women of different ages and Earth‘s local magnetic field‘s fluctuation during ph...

  17. Intensity-dependent EMG response for the biceps brachii during sustained maximal and submaximal isometric contractions.

    Science.gov (United States)

    Carr, Joshua C; Beck, Travis W; Ye, Xin; Wages, Nathan P

    2016-09-01

    There have been recent attempts to characterize the mechanisms associated with fatigue-induced task failure. We compared the time to failure and the corresponding changes in the surface electromyogram (EMG) during sustained maximal and submaximal isometric force tasks. EMG activity was measured from the biceps brachii of 18 male participants as they sustained either a maximal or submaximal (60 % MVC) isometric contraction of the dominant elbow flexors until force could not be maintained above 55 % MVC. Intensity-dependent patterns of change were observed for EMG amplitude and mean power frequency (MNF) between the two force tasks. Interestingly, the only significant predictor of failure time was the rate of change in EMG MNF during the submaximal task (r (2) = 0.304). In addition, EMG amplitude at submaximal failure was significantly lower (p EMG response emphasize the basis of neuromuscular fatigue and task dependency. Additionally, our data suggest that the EMG MNF should be used when monitoring the progression of local muscle fatigue.

  18. THE EFFECT OF SUBMAXIMAL INHALATION ON MEASURES DERIVED FROM FORCED EXPIRATORY SPIROMETRY

    Science.gov (United States)

    THE EFFECT OF SUBMAXIMAL INHALATION ON MEASURES DERIVED FROM FORCED EXPIRATORY SPIROMETRY. William F. McDonnell Human Studies Division, NHEERL, U.S. Environmental Protection Agency, RTP, NC 27711. Short-term exposure to ozone results in a neurally-mediated decrease in the ab...

  19. Calibration of EMG to force for knee muscles is applicable with submaximal voluntary contractions

    NARCIS (Netherlands)

    Doorenbosch, C.A.M.; Joosten, A.; Harlaar, J.

    2005-01-01

    Purpose: In this study, the influence of using submaximal isokinetic contractions about the knee compared to maximal voluntary contractions as input to obtain the calibration of an EMG-force model for knee muscles is investigated. Methods: Isokinetic knee flexion and extension contractions were

  20. Variability of Respiration and Metabolism: Responses to Submaximal Cycling and Running.

    Science.gov (United States)

    Armstrong, Lawrence E.; Costill, David L.

    1985-01-01

    This investigation examined day-to-day variations in metabolic measurements during submaximal running and cycling. Significant differences were found in the oxygen uptake (VO2) of runners and cyclists and the minute ventilation (VE) of cyclists while running, but blood lactic acid (HLA) did not differ day to day. (Author/MT)

  1. Safety and feasibility of regadenoson use for suboptimal heart rate response during symptom-limited standard Bruce exercise stress test.

    Science.gov (United States)

    Partington, Sara L; Lanka, Viswanatha; Hainer, Jon; Blankstein, Ron; Skali, Hicham; Forman, Daniel E; Di Carli, Marcelo F; Dorbala, Sharmila

    2012-10-01

    Regadenoson during exercise stress test (ETT) can provide maximal hyperemia for myocardial perfusion imaging (MPI), along with exercise information. Our aim was to study the feasibility and safety of regadenoson injection at peak ETT for submaximal heart rate (HR) response. Consecutive patients who underwent SPECT MPI with standard Bruce ETT or supine-regadenoson (Supine-Reg) were analyzed. ETT patients were grouped as ETT-Max [maximal HR > 0.85 * (220 - age), N = 1,522], ETT-Submax (submaximal HR no regadenoson, N = 504), ETT-Reg (submaximal HR and regadenoson, N = 211). The HR during ETT was submaximal in 715 (32%) patients. Of these, 211 patients (30%) underwent ETT-Reg (mean exercise duration: 5.5 ± 2.5 minutes). ETT-Reg patients had a higher frequency of hypertension, diabetes, smoking and beta-blocker use, similar rest systolic blood pressure (SBP), but lower rest and peak HR and peak SBP compared to ETT-Max patients. There were no serious complications with regadenoson. Side effects (49% vs 6%, P < .0001) were fewer and aminophylline use was lower with ETT-Reg compared to Supine-Reg (0.5% vs 8.1%, P = .001). Submaximal HR response to ETT is common. ETT-Reg is safe, feasible, and well-tolerated. ETT-Reg facilitates a diagnostic MPI with reporting of functional capacity, exercise ECG/hemodynamic changes and MPI at maximal hyperemia.

  2. Heavy strength training improves running and cycling performance following prolonged submaximal work in well-trained female athletes.

    Science.gov (United States)

    Vikmoen, Olav; Rønnestad, Bent R; Ellefsen, Stian; Raastad, Truls

    2017-03-01

    The purpose of this study was to investigate the effects of adding heavy strength training to female duathletes' normal endurance training on both cycling and running performance. Nineteen well-trained female duathletes ( V O 2max cycling: 54 ± 3 ml∙kg -1 ∙min -1 , VO 2max running: 53 ± 3 ml∙kg -1 ∙min -1 ) were randomly assigned to either normal endurance training ( E , n  = 8) or normal endurance training combined with strength training ( E+S , n  = 11). The strength training consisted of four lower body exercises [3 × 4-10 repetition maximum (RM)] twice a week for 11 weeks. Running and cycling performance were assessed using 5-min all-out tests, performed immediately after prolonged periods of submaximal work (3 h cycling or 1.5 h running). E+S increased 1RM in half squat (45 ± 22%) and lean mass in the legs (3.1 ± 4.0%) more than E Performance during the 5-min all-out test increased in both cycling (7.0 ± 4.5%) and running (4.7 ± 6.0%) in E+S, whereas no changes occurred in E The changes in running performance were different between groups. E+S reduced oxygen consumption and heart rate during the final 2 h of prolonged cycling, whereas no changes occurred in E No changes occurred during the prolonged running in any group. Adding strength training to normal endurance training in well-trained female duathletes improved both running and cycling performance when tested immediately after prolonged submaximal work. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  3. Cardiovascular control during exercise in type 2 diabetes mellitus.

    Science.gov (United States)

    Green, Simon; Egaña, Mikel; Baldi, J Chris; Lamberts, Regis; Regensteiner, Judith G

    2015-01-01

    Controlled studies of male and female subjects with type 2 diabetes mellitus (DM) of short duration (~3-5 years) show that DM reduces peak VO2 (L·min(-1) and mL·kg(-1)·min(-1)) by an average of 12-15% and induces a greater slowing of the dynamic response of pulmonary VO2 during submaximal exercise. These effects occur in individuals less than 60 years of age but are reduced or absent in older males and are consistently associated with significant increases in the exercise pressor response despite normal resting blood pressure. This exaggerated pressor response, evidence of exertional hypertension in DM, is manifest during moderate submaximal exercise and coincides with a more constrained vasodilation in contracting muscles. Maximum vasodilation during contractions involving single muscle groups is reduced by DM, and the dynamic response of vasodilation during submaximal contractions is slowed. Such vascular constraint most likely contributes to exertional hypertension, impairs dynamic and peak VO2 responses, and reduces exercise tolerance. There is a need to establish the effect of DM on dynamic aspects of vascular control in skeletal muscle during whole-body exercise and to clarify contributions of altered cardiovascular control and increased arterial stiffness to exertional hypertension.

  4. Reciprocal effects of treatment-induced increases in exercise and improved eating, and their psychosocial correlates, in obese adults seeking weight loss: a field-based trial.

    Science.gov (United States)

    Annesi, James J; Porter, Kandice J

    2013-12-05

    A better understanding of interrelations of exercise and improved eating, and their psychosocial correlates of self-efficacy, mood, and self-regulation, may be useful for the architecture of improved weight loss treatments. Theory-based research within field settings, with samples possessing high probabilities of health risks, might enable rapid application of useful findings. Adult volunteers with severe obesity (body mass index [BMI] 35-50 kg/m²; age = 43.0 ± 9.5 y; 83% female) were randomly assigned to six monthly cognitive-behavioral exercise support sessions paired with either group-based nutrition education (n = 145) or cognitive behavioral methods applied to improved eating (n = 149). After specification of mediation models using a bias-corrected bootstrapping procedure, a series of reciprocal effects analyses assessed: a) the reciprocal effects of changes in exercise and fruit and vegetable intake, resulting from the treatments, b) the reciprocal effects of changes in the three psychosocial variables tested (i.e. self-efficacy, mood, and self-regulation) and fruit and vegetable change, resulting from change in exercise volume, and c) the reciprocal effects of changes in the three psychosocial variables and exercise change, resulting from change in fruit and vegetable intake. Mediation analyses suggested a reciprocal effect between changes in exercise volume and fruit and vegetable intake. After inclusion of psychosocial variables, also found were reciprocal effects between change in fruit and vegetable intake and change in mood, self-efficacy for controlled eating, and self-regulation for eating; and change in exercise volume and change in mood and exercise-related self-regulation. Findings had implications for behavioral weight-loss theory and treatment. Specifically, results suggested that treatments should focus upon, and leverage, the transfer effects from each of the primary weight-loss behaviors (exercise and healthy eating) to the other. Findings

  5. Dynamic cerebral autoregulation changes during sub-maximal handgrip maneuver.

    Directory of Open Access Journals (Sweden)

    Ricardo C Nogueira

    Full Text Available PURPOSE: We investigated the effect of handgrip (HG maneuver on time-varying estimates of dynamic cerebral autoregulation (CA using the autoregressive moving average technique. METHODS: Twelve healthy subjects were recruited to perform HG maneuver during 3 minutes with 30% of maximum contraction force. Cerebral blood flow velocity, end-tidal CO₂ pressure (PETCO₂, and noninvasive arterial blood pressure (ABP were continuously recorded during baseline, HG and recovery. Critical closing pressure (CrCP, resistance area-product (RAP, and time-varying autoregulation index (ARI were obtained. RESULTS: PETCO₂ did not show significant changes during HG maneuver. Whilst ABP increased continuously during the maneuver, to 27% above its baseline value, CBFV raised to a plateau approximately 15% above baseline. This was sustained by a parallel increase in RAP, suggestive of myogenic vasoconstriction, and a reduction in CrCP that could be associated with metabolic vasodilation. The time-varying ARI index dropped at the beginning and end of the maneuver (p<0.005, which could be related to corresponding alert reactions or to different time constants of the myogenic, metabolic and/or neurogenic mechanisms. CONCLUSION: Changes in dynamic CA during HG suggest a complex interplay of regulatory mechanisms during static exercise that should be considered when assessing the determinants of cerebral blood flow and metabolism.

  6. Evaluation of the Ration, Cold Weather during a 10-Day Cold Weather Field Training Exercise

    Science.gov (United States)

    1987-06-15

    the field, medics collected a daily sample from each subject’s first urine and recorded specific gravity and ketone levels as indicated by dipsticks...Rice ^’^ (± u-^J Chicken Soup ^’j ^.^I’ll Fruit Soup (Strawberry) ^-^ T n ^^ Fruit Soup ( Raspberry ) ^’^ (± u.aj Lemon Tea 5 9 ?4. 0.6...Soup ( Raspberry ) 20 Lemon Tea 31 Orange Beverage 24 Cocoa *0 Coffee ^7 Apple Cider ^^ Cookies (Chocolate Covered) 62 Cookies (Oatmeal) 69

  7. Non-invasive measurement of adrenal response after standardized exercise tests in prepubertal children

    NARCIS (Netherlands)

    Heijsman, Sigrid M.; Koers, Nicoline F.; Bocca, Gianni; van der Veen, Betty S.; Appelhof, Maaike; Kamps, Arvid W. A.

    Objective: To determine the feasibility of non-invasive evaluation of adrenal response in healthy prepubertal children by standardized exercise tests. Methods: On separate occasions, healthy prepubertal children performed a submaximal cycling test, a maximal cycling test, and a 20-m shuttle-run

  8. A Submaximal Running Test With Postexercise Cardiac Autonomic and Neuromuscular Function in Monitoring Endurance Training Adaptation.

    Science.gov (United States)

    Vesterinen, Ville; Nummela, Ari; Laine, Tanja; Hynynen, Esa; Mikkola, Jussi; Häkkinen, Keijo

    2017-01-01

    Vesterinen, V, Nummela, A, Laine, T, Hynynen, E, Mikkola, J, and Häkkinen, K. A submaximal running test with postexercise cardiac autonomic and neuromuscular function in monitoring endurance training adaptation. J Strength Cond Res 31(1): 233-243, 2017-The aim of this study was to investigate whether a submaximal running test (SRT) with postexercise heart rate recovery (HRR), heart rate variability (HRV), and countermovement jump (CMJ) measurements could be used to monitor endurance training adaptation. Thirty-five endurance-trained men and women completed an 18-week endurance training. Maximal endurance performance and maximal oxygen uptake were measured every 8 weeks. In addition, SRTs with postexercise HRR, HRV, and CMJ measurements were carried out every 4 weeks. Submaximal running test consisted of two 6-minute stages at 70 and 80% of maximum heart rate (HRmax) and a 3-minute stage at 90% HRmax, followed by a 2-minute recovery stage for measuring postexercise HRR, HRV, and CMJ test. The highest responders according to the change of maximal endurance performance showed a significant improvement in running speeds during stages 2 and 3 in SRT, whereas no changes were observed in the lowest responders. The strongest correlation was found between the change of maximal endurance performance and running speed during stage 3, whereas no significant relationships were found between the change of maximal endurance performance and the changes of postexercise HRR, HRV, and CMJ. Running speed at 90% HRmax intensity was the most sensitive variable to monitor adaptation to endurance training. The present submaximal test showed potential to monitor endurance training adaptation. Furthermore, it may serve as a practical tool for athletes and coaches to evaluate weekly the effectiveness of training program without interfering in the normal training habits.

  9. Aircraft Field Exercise to Develop Multi-Spectral and Infrared Imaging for CTBT On-Site Inspections

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, J R [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Smith, M O [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zelinski, M E [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-08-23

    The Comprehensive Test Ban Treaty (CTBT) permits Multi-Spectral and InfraRed Imaging (MSIR) to be performed as part of an On-Site Inspection (OSI) for the purpose of reducing the search area for the location of a possible underground nuclear explosion (UNE). Dedicated airborne MSIR measurements have not been made in conjunction with historical or recent UNE’s. Satellite data has been used to show that MSIR observables can be used to reduce the search area, but the satellite data do not have the spatial resolution or spectral and thermal capabilities desired to fully characterize the MSIR observables. Consequently, there is insufficient information currently available to confidently specify an MSIR instrument to be used on an Additional Overflight as part of an OSI. The potential MSIR observables are known, but not well characterized. The possibility of using airborne MSIR measurements to characterize some of those observables has been assessed here for a variety of field exercise scenarios. The main challenge in making aircraft measurements is to have confidence that the field conditions will accurately reproduce the MSIR observable compared to a UNE. The four types of events expected to generate relevant MSIR observables are (1) underground coal fires, (2) road traffic measurements, (3) underground mining operations, and (4) certain carefully staged explosions, such as the Source Physics Experiment.

  10. Erythrocyte membrane fluidity and indices of plasmatic oxidative damage after acute physical exercise in humans.

    Science.gov (United States)

    Berzosa, C; Gómez-Trullén, E M; Piedrafita, E; Cebrián, I; Martínez-Ballarín, E; Miana-Mena, F J; Fuentes-Broto, L; García, J J

    2011-06-01

    Optimal levels of membrane fluidity are essential for numerous cell functions including cell growth, solute transport and signal transduction. Since exercise enhances free radical production, our aim was to evaluate in healthy male subjects the effects of an acute bout of maximal and submaximal exercise on the erythrocyte membrane fluidity and its possible relation to the oxidative damage overproduction due to exercise. Subjects (n = 34) performed three cycloergometric tests: a continuous progressive exercise, a strenuous exercise until exhaustion and an acute bout of exercise at an intensity corresponding to 70% of maximal work capacity for 30 min. Venous blood samples were collected before and immediately after these exercises. Erythrocyte membrane fluidity was assessed by fluorescence spectroscopy. Plasma malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) concentrations and carbonyl content of plasmatic proteins were used as an index of lipid and protein oxidation, respectively. Exercise produced a dramatic drop in the erythrocyte membrane fluidity as compared to resting time, but this was not accompanied by significant changes in the plasmatic MDA and 4-HDA concentrations. The highest erythrocyte membrane rigidity was detected immediately after strenuous exercise until exhaustion was performed. Protein carbonyl levels were higher after exhaustive exercises than at rest. Continuous progressive and strenuous exercises until exhaustion, but not submaximal workload, resulted in a significant enhanced accumulation of carbonylated proteins in the plasma. These findings are consistent with the idea that exercise exaggerates oxidative damage, which may contribute, at least partially, to explain the rigidity in the membrane of the erythrocytes due to acute exercise.

  11. Characterization of Symmetry Properties of First Integrals for Submaximal Linearizable Third-Order ODEs

    Directory of Open Access Journals (Sweden)

    K. S. Mahomed

    2013-01-01

    Full Text Available The relationship between first integrals of submaximal linearizable third-order ordinary differential equations (ODEs and their symmetries is investigated. We obtain the classifying relations between the symmetries and the first integral for submaximal cases of linear third-order ODEs. It is known that the maximum Lie algebra of the first integral is achieved for the simplest equation and is four-dimensional. We show that for the other two classes they are not unique. We also obtain counting theorems of the symmetry properties of the first integrals for these classes of linear third-order ODEs. For the 5 symmetry class of linear third-order ODEs, the first integrals can have 0, 1, 2, and 3 symmetries, and for the 4 symmetry class of linear third-order ODEs, they are 0, 1, and 2 symmetries, respectively. In the case of submaximal linear higher-order ODEs, we show that their full Lie algebras can be generated by the subalgebras of certain basic integrals.

  12. Effects of continuous vs interval exercise training on oxygen uptake efficiency slope in patients with coronary artery disease

    OpenAIRE

    Prado, D.M.L.; Rocco,E.A.; SILVA, A. G.; Rocco, D.F.; Pacheco, M.T.; Silva,P.F.; Furlan, V

    2016-01-01

    The oxygen uptake efficiency slope (OUES) is a submaximal index incorporating cardiovascular, peripheral, and pulmonary factors that determine the ventilatory response to exercise. The purpose of this study was to evaluate the effects of continuous exercise training and interval exercise training on the OUES in patients with coronary artery disease. Thirty-five patients (59.3±1.8 years old; 28 men, 7 women) with coronary artery disease were randomly divided into two groups: continuous exercis...

  13. "Sport & Exercise Pedagogy". The Case for a New Integrative Sub-Discipline in the Field of Sport & Exercise Sciences/Kinesiology/Human Movement Sciences

    Science.gov (United States)

    Armour, Kathleen M.; Chambers, Fiona C.

    2014-01-01

    The European Union Sport Unit has identified the societal and educational role of sport as a central topic in its new research agenda. It is argued that European Union (EU) citizens should be supported to learn continuously across the life course. In the sport/physical activity (PA) context, the role of teachers, coaches and exercise instructors…

  14. Effects of aerobic endurance, muscle strength, and motor control exercise on physical fitness and musculoskeletal injury rate in preprofessional dancers: an uncontrolled trial.

    Science.gov (United States)

    Mistiaen, Wilhelm; Roussel, Nathalie A; Vissers, Dirk; Daenen, Liesbeth; Truijen, Steven; Nijs, Jo

    2012-06-01

    The purpose of this study was to evaluate musculoskeletal injury rate and physical fitness before and 6 months after an endurance, strength, and motor control exercise program in preprofessional dancers. This uncontrolled trial was completed at a college offering a professional bachelor degree in dance. Forty preprofessional dancers underwent a test battery before and after a 6-month lasting exercise program in addition to their regular dance lessons. Physical fitness was evaluated by means of a submaximal exercise test with continuous physiological monitoring and by a field test for explosive strength. Anthropometric measurements were taken to analyze the influence of fitness training on body composition. Musculoskeletal injury incidence and quality of life were recorded during the 6-month lasting intervention. An intention-to-treat analysis ("last observation carried forward" method) was used with a Student t test for normally distributed variables. The Wilcoxon signed rank and Mann-Whitney U tests were used as nonparametric tests. Physical fitness improved after the 6 months of additional training program (Pdancing. The combination of regular dance lessons with an additional exercise program resulted in improved physical fitness in preprofessional dancers, without affecting the aesthetical appearance. A relatively high injury rate was observed during the intervention period. These results suggest that a randomized, controlled trial should be performed to examine the effectiveness of additional exercise in dancers on physical fitness and musculoskeletal injury rate. Copyright © 2012 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  15. A Naval Academy midshipman with ehrlichiosis after summer field exercises in Quantico, Virginia.

    Science.gov (United States)

    Rooney, T B; McGue, T E; Delahanty, K C

    2001-02-01

    A case of human ehrlichiosis (caused by infection with Ehrlichia chaffeensis) is presented. The patient was a female Naval Academy midshipman with a 26-day history of daily field training with the U.S. Marines near Quantico, Virginia. She presented with a several-day history of myalgias, fever, and frontal headache. During her clinical course, she developed fever to 104 degrees F, dry cough, dyspnea on exertion, arthralgias, and nephrotic syndrome. She did not develop a rash. Laboratory studies were significant for thrombocytopenia, equivocal Lyme enzyme immunosorbent assay with a negative confirmatory western immunoblot, equivocal Rocky Mountain spotted fever acute serology without a convalescent increase in immunoglobulin G, and immunoglobulin G/immunoglobulin M serology positive for human monocytic ehrlichiosis. She manifested known sequelae for this emerging disease, including dyspnea, pedal edema, increased transminases, and nephrotic syndrome.

  16. Battlefield ethics training: integrating ethical scenarios in high-intensity military field exercises

    Directory of Open Access Journals (Sweden)

    Megan M. Thompson

    2014-08-01

    Full Text Available There is growing evidence that modern missions have added stresses and ethical complexities not seen in previous military operations and that there are links between battlefield stressors and ethical lapses. Military ethicists have concluded that the ethical challenges of modern missions are not well addressed by current military ethics educational programs. Integrating the extant research in the area, we propose that scenario-based operational ethics training in high-intensity military field training settings may be an important adjunct to traditional military ethics education and training. We make the case as to why this approach will enhance ethical operational preparation for soldiers, supporting their psychological well-being as well as mission effectiveness.

  17. Impact of wireless electronic medical record system on the quality of patient documentation by emergency field responders during a disaster mass-casualty exercise.

    Science.gov (United States)

    Chan, Theodore C; Griswold, William G; Buono, Colleen; Kirsh, David; Lyon, Joachim; Killeen, James P; Castillo, Edward M; Lenert, Leslie

    2011-08-01

    The use of wireless, electronic, medical records and communications in the prehospital and disaster field is increasing. This study examines the role of wireless, electronic, medical records and communications technologies on the quality of patient documentation by emergency field responders during a mass-casualty exercise. A controlled, side-to-side comparison of the quality of the field responder patient documentation between responders utilizing National Institutes of Health-funded, wireless, electronic, field, medical record system prototype ("Wireless Internet Information System for medicAl Response to Disasters" or WIISARD) versus those utilizing conventional, paper-based methods during a mass-casualty field exercise. Medical data, including basic victim identification information, acuity status, triage information using Simple Triage and Rapid Treatment (START), decontamination status, and disposition, were collected for simulated patients from all paper and electronic logs used during the exercise. The data were compared for quality of documentation and record completeness comparing WIISARD-enabled field responders and those using conventional paper methods. Statistical analysis was performed with Fisher's Exact Testing of Proportions with differences and 95% confidence intervals reported. One hundred simulated disaster victim volunteers participated in the exercise, 50 assigned to WIISARD and 50 to the conventional pathway. Of those victims who completed the exercise and were transported to area hospitals, medical documentation of victim START components and triage acuity were significantly better for WIISARD compared to controls (overall acuity was documented for 100% vs 89.5%, respectively, difference = 10.5% [95%CI = 0.5-24.1%]). Similarly, tracking of decontamination status also was higher for the WIISARD group (decontamination status documented for 59.0% vs 0%, respectively, difference = 9.0% [95%CI = 40.9-72.0%]). Documentation of disposition and

  18. Exercise capacity in lean versus obese women.

    Science.gov (United States)

    Hulens, M; Vansant, G; Lysens, R; Claessens, A L; Muls, E

    2001-10-01

    The aim of this study was to assess the nature and magnitude of the differences in submaximal and maximal exercise capacity parameters between lean and obese women. A total of 225 healthy obese women 18-65 years (BMI> or=30 kg/m(2)) and 81 non-athletic lean women (BMI< or=26 kg/m(2)) were selected. Anthropometric measurements (weight and height), body composition assessment (bioelectrical impedance method) and a maximal exercise capacity test on a bicycle ergometer were performed. Oxygen uptake (VO(2)), carbon dioxide production (VCO(2)), expired ventilation (VE), respiratory quotient (RQ), breathing efficiency (VE/VO(2)), mechanical efficiency (ME) and anaerobic threshold (AT) were calculated. At a submaximal intensity load of 70 W, VO(2) (l/min) was larger in the obese women and was already 78% of their peak VO(2), whereas in the non-obese it was only 69% (P=0.0001). VE (l/min) was larger, VE/VO(2) did not differ and ME was lower in obese compared to the lean women. AT occurred at the same percentage of peak VO(2) in both lean and obese women. At peak effort, achieved load, terminal VO(2) (l min(-1) kg(-1)), VE, heart rate, RQ respiratory exchange ratio and perceived exertion were lower in obese subjects compared to the non-obese. Obese subjects mentioned significantly more musculoskeletal pain as a reason to end the test, whereas in lean subjects it was leg fatigue. Lean women recovered better as after 2 min they were already at 35% of the peak VO(2), whereas in the obese women it was 47% (P=0.0001). Our results confirm that exercise capacity is decreased in obesity, both at submaximal and peak intensity, and during recovery. Moreover, at peak effort musculoskeletal pain was an important reason to end the test and not true leg fatigue. These findings are important when designing exercise programs for obese subjects.

  19. Effect of strength training with blood flow restriction on muscle power and submaximal strength in eumenorrheic women.

    Science.gov (United States)

    Gil, Ana L S; Neto, Gabriel R; Sousa, Maria S C; Dias, Ingrid; Vianna, Jeferson; Nunes, Rodolfo A M; Novaes, Jefferson S

    2017-03-01

    Blood flow restriction (BFR) training stimulates muscle size and strength by increasing muscle activation, accumulation of metabolites and muscle swelling. This method has been used in different populations, but no studies have evaluated the effects of training on muscle power and submaximal strength (SS) in accounted for the menstrual cycle. The aim of this study was to analyse the effect of strength training (ST) with BFR on the muscle power and SS of upper and lower limbs in eumenorrheic women. Forty untrained women (18-40 years) were divided randomly and proportionally into four groups: (i) high-intensity ST at 80% of 1RM (HI), (ii) low-intensity ST at 20% of 1RM combined with partial blood flow restriction (LI + BFR), (iii) low-intensity ST at 20% of 1RM (LI) and d) control group (CG). Each training group performed eight training sessions. Tests with a medicine ball (MB), horizontal jump (HJ), vertical jump (VJ), biceps curls (BC) and knee extension (KE) were performed during the 1st day follicular phase (FP), 14th day (ovulatory phase) and 26-28th days (luteal phase) of the menstrual cycle. There was no significant difference among groups in terms of the MB, HJ, VJ or BC results at any time point (P>0·05). SS in the KE exercise was significantly greater in the LI + BFR group compared to the CG group (P = 0·014) during the LP. Therefore, ST with BFR does not appear to improve the power of upper and lower limbs and may be an alternative to improve the SS of lower limbs of eumenorrheic women. © 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  20. Effects of Dietary Acid Load on Exercise Metabolism and Anaerobic Exercise Performance

    Directory of Open Access Journals (Sweden)

    Susan L. Caciano, Cynthia L. Inman, Elizabeth E. Gockel-Blessing, Edward P. Weiss

    2015-06-01

    Full Text Available Dietary acid load, quantified as the potential renal acid load (PRAL of the diet, affects systemic pH and acid-base regulation. In a previous cross-sectional study, we reported that a low dietary PRAL (i.e. alkaline promoting diet is associated with higher respiratory exchange ratio (RER values during maximal exercise. The purpose of the present study was to confirm the previous findings with a short-term dietary intervention study. Additionally, we sought to determine if changes in PRAL affects submaximal exercise RER (as a reflection of substrate utilization and anaerobic exercise performance. Subjects underwent a graded treadmill exercise test (GXT to exhaustion and an anaerobic exercise performance test on two occasions, once after following a low-PRAL diet and on a separate occasion, after a high-PRAL diet. The diets were continued as long as needed to achieve an alkaline or acid fasted morning urine pH, respectively, with all being 4-9 days in duration. RER was measured during the GXT with indirect calorimetry. The anaerobic performance test was a running time-to-exhaustion test lasting 1-4 min. Maximal exercise RER was lower in the low-PRAL trial compared to the high-PRAL trial (1.10 ± 0.02 vs. 1.20 ± 0.05, p = 0.037. The low-PRAL diet also resulted in a 21% greater time to exhaustion during anaerobic exercise (2.56 ± 0.36 vs. 2.11 ± 0.31 sec, p = 0.044 and a strong tendency for lower RER values during submaximal exercise at 70% VO2max (0.88 ± 0.02 vs. 0.96 ± 0.04, p = 0.060. Contrary to our expectations, a short-term low-PRAL (alkaline promoting diet resulted in lower RER values during maximal-intensity exercise. However, the low-PRAL diet also increased anaerobic exercise time to exhaustion and appears to have shifted submaximal exercise substrate utilization to favor lipid oxidation and spare carbohydrate, both of which would be considered favorable effects in the context of exercise performance.

  1. Separate and combined effects of exercise training and weight loss on exercise efficiency and substrate oxidation.

    Science.gov (United States)

    Amati, Francesca; Dubé, John J; Shay, Chris; Goodpaster, Bret H

    2008-09-01

    Perturbations in body weight have been shown to affect energy expenditure and efficiency during physical activity. The separate effects of weight loss and exercise training on exercise efficiency or the proportion of energy derived from fat oxidation during physical activity, however, are not known. The purpose of this study was to determine the separate and combined effects of exercise training and weight loss on metabolic efficiency, economy (EC), and fat oxidation during steady-state moderate submaximal exercise. Sixty-four sedentary older (67 +/- 0.5 yr) overweight to obese (30.7 +/- 0.4 kg/m(2)) volunteers completed 4 mo of either diet-induced weight loss (WL; n = 11), exercise training (EX; n = 36), or the combination of both interventions (WLEX; n = 17). Energy expenditure, gross efficiency (GE), EC, and proportion of energy expended from fat (EF) were determined during a 1-h submaximal (50% of peak aerobic capacity) cycle ergometry exercise before the intervention and at the same absolute work rate after the intervention. We found that EX increased GE by 4.7 +/- 2.2%. EC was similarly increased by 4.2 +/- 2.1% by EX. The addition of concomitant WL to EX (WLEX) resulted in greater increases in GE (9.0 +/- 3.3%) compared with WL alone but not compared with EX alone. These effects remained after adjusting for changes in lean body mass. The proportion of energy derived from fat during the bout of moderate exercise increased with EX and WLEX but not with WL. From these findings, we conclude that exercise training, either alone or in combination with weight loss, increases both exercise efficiency and the utilization of fat during moderate physical activity in previously sedentary, obese older adults. Weight loss alone, however, significantly improves neither efficiency nor utilization of fat during exercise.

  2. Reflecting on the PRET A Rapporter Framework Via a Field Study of Adolescents? Perceptions of Technology and Exercise

    Directory of Open Access Journals (Sweden)

    Helen M Edwards

    2013-01-01

    Full Text Available PRET A Rapporter (PRETAR was developed to explicitly structure user-centered evaluation studies to ensure all necessary elements are individually and independently considered. Its creators see its benefit as twofold: for study design and in retrospective evaluations. We evaluate PRETAR’s potential by applying it retrospectively to one of our eHealth field studies in which we investigated the design requirements for mobile technologies that would support and motivate adolescents to exercise opportunistically. We also use PRETAR to evaluate the key literature for this eHealth study. This shows that typically the research methodology is under-reported. Then we document the study in terms of its purpose, resources, ethical concerns, data collection and analysis techniques, and manner of reporting the study. Finally, our reflection on the use of PRETAR leads us to propose that four different modes of the framework should be applied during the course of a study, that is, when reviewing, planning, conducting, and discussing.

  3. Music during exercise: does tempo influence psychophysical responses?

    OpenAIRE

    Elliott, David

    2007-01-01

    This study examined whether music of different tempi would influence the psychophysical responses of exercise participants performing a sub-maximal cycle task. Specifically, the investigation assessed the effect of musical tempo upon aerobic work rate and whether dissociation, and/or, arousal could be implicated in any physical responses. Eighteen student participants (10 females, 8 males) were required to partake in four experimental conditions: no music, ‘slow’ music, ‘moderately fast’ musi...

  4. Virtual Reality Exercise for Anxiety and Depression: A Preliminary Review of Current Research in an Emerging Field

    Directory of Open Access Journals (Sweden)

    Nan Zeng

    2018-03-01

    Full Text Available Objective: Although current evidence supports the use of virtual reality (VR in the treatment of mental disorders, it is unknown whether VR exercise would be beneficial to mental health. This review synthesized literature concerning the effect of VR exercise on anxiety and depression among various populations. Methods: Ten electronic databases were searched for studies on this topic from January 2000 through October 2017. Studies were eligible if the article: (1 was peer-reviewed; (2 was published in English; and (3 used quantitative measures in assessing anxiety- and depression-related outcomes. Results: A total of five empirical studies met the eligibility criteria. These studies included two randomized clinical trials, one control trial, and two cross-sectional studies. Four studies reported significant improvements in anxiety- and depression-related measures following VR exercise, including reduced tiredness and tension, in addition to increased energy and enjoyment. Nonetheless, one study failed to support the effectiveness of VR exercise over traditional exercise alone on depressive symptoms. Conclusions: Findings favor VR exercise in alleviating anxiety and depression symptomology. However, existing evidence is insufficient to support the advantages of VR exercise as a standalone treatment over traditional therapy in the alleviation of anxiety and depression given the paucity of studies, small sample sizes, and lack of high-quality research designs. Future studies may build upon these limitations to discern the optimal manner by which to employ VR exercise in clinical settings.

  5. Optoelectronic plethysmography compared to spirometry during maximal exercise.

    Science.gov (United States)

    Layton, Aimee M; Moran, Sienna L; Garber, Carol Ewing; Armstrong, Hilary F; Basner, Robert C; Thomashow, Byron M; Bartels, Matthew N

    2013-01-15

    The purpose of this study was to compare simultaneous measurements of tidal volume (Vt) by optoelectronic plethysmography (OEP) and spirometry during a maximal cycling exercise test to quantify possible differences between methods. Vt measured simultaneously by OEP and spirometry was collected during a maximal exercise test in thirty healthy participants. The two methods were compared by linear regression and Bland-Altman analysis at submaximal and maximal exercise. The average difference between the two methods and the mean percentage discrepancy were calculated. Submaximal exercise (SM) and maximal exercise (M) Vt measured by OEP and spirometry had very good correlation, SM R=0.963 (pspirometry. OEP could measure exercise Vt as much as 0.188 L above and -0.017 L below that of spirometry. The discrepancy between measurements was -2.0 ± 7.2% at SM and -2.4 ± 3.9% at M. In conclusion, Vt measurements at during exercise by OEP and spirometry are closely correlated and the difference between measurements was insignificant. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Tear osmolarity is sensitive to exercise-induced fluid loss but is not associated with common hydration measures in a field setting.

    Science.gov (United States)

    Holland, Justin J; Ray, Michelle; Irwin, Christopher; Skinner, Tina L; Leveritt, Michael; Desbrow, Ben

    2017-08-16

    This investigation (i) examined changes in tear osmolarity in response to fluid loss that occurs with exercise in a field setting, and (ii) compared tear osmolarity with common field and laboratory hydration measures.  Sixty-three participants [age 27.8 ± 8.4 years, body mass 72.15 ± 10.61 kg] completed a self-paced 10 km run outside on a predetermined course. Body mass, tear fluid, venous blood and urine samples were collected immediately before and after exercise.  Significant (p  0.05) with plasma osmolality (rs = 0.24), urine osmolality (rs = 0.14), urine specific gravity (rs = 0.13) or relative body mass loss (r = 0.20).  Tear osmolarity is responsive to exercise-induced fluid loss but does not correlate with the changes observed using other common measures of hydration status in the field setting. Practitioners shouldn't directly compare or replace other common hydration measures with tear osmolarity in the field. BML: Body Mass Loss; CV: Coefficient of Variation; Posm: Plasma osmolality; SD: Standard Deviation; Tosm: Tear Osmolarity; Uosm: Urine Osmolality; USG: Urine Specific Gravity; WBGT: Wet bulb globe thermometer.

  7. Exercise thermoregulation after 14 days of bed rest

    Science.gov (United States)

    Greenleaf, J. E.; Reese, R. D.

    1980-01-01

    The effects of bed rest and exercise training during bed rest on body temperature and thermoregulatory responses at rest and during exercise are investigated. Seven male subjects underwent three two-week periods of bed rest during which isometric, isotonic, or no exercises were performed, separated by two ambulatory control periods and preceded by a two-week control period, during which they exercised regularly. Rectal and mean skin temperatures and sweating responses were determined during 70-min submaximal supine exercise during the bed rest and recovery periods. Measurements reveal a reduction in basal oral temperature during the control-recovery periods, with a relatively constant level during bed rest periods, and a significant increase in the rectal temperature elavation brought on by exercise following all three bed-rest regimes. It is concluded that the excessive increase in rectal temperature could be influenced by changes in skin heat conductance or the inhibition of sweating.

  8. Effects of music during exercise in different training status.

    Science.gov (United States)

    Baldari, C; Macone, D; Bonavolontà, V; Guidetti, L

    2010-09-01

    This study examined the interaction of exercise and music to establish the impact of these factors on state-anxiety and time to exhaustion comparing trained and active participants. Twenty-six university students (13 trained, 13 active) completed the State-anxiety Inventory questionnaire before and after a submaximal treadmill running until volitional exhaustion in both music and no-music condition. ANOVA showed that both trained and active groups significantly reduced their State-Anxiety scores after exercise tasks (Pmusic. Finding also revealed that active group reported a higher significant reduction of their state anxiety score after exercise in music condition compared to no-music task (Pmusic (Pmusic during exercise may improve this effect in active but not in trained participants. Further, listening to music during exercise may prolong the participants' exercise experience but different training status seems to qualify differently this response.

  9. Heart rate response and parasympathetic modulation during recovery from exercise in boys and men.

    Science.gov (United States)

    Guilkey, Justin P; Overstreet, Matthew; Fernhall, Bo; Mahon, Anthony D

    2014-08-01

    The purpose of this study was to examine the influence of postexercise parasympathetic modulation, measured by heart rate variability (HRV), on heart rate recovery (HRR) in boys (n = 13, 10.1 ± 0.8 years) and men (n = 13, 23.9 ± 1.5 years) following maximal and submaximal exercise. Subjects completed 10 min of supine rest, followed by graded exercise on a cycle ergometer to maximal effort. On a separate day, subjects exercised at an intensity equivalent to ventilatory threshold. Immediately following both exercise bouts, 1-min HRR was assessed in the supine position. HRV was analyzed under controlled breathing during the final 5 min of rest and recovery in the time and frequency domains and transformed to natural log (ln) values. Boys had a greater 1-min HRR than men following maximal (58 ± 8 vs. 47 ± 11 beats·min(-1)) and submaximal (59 ± 8 vs. 47 ± 15 beats·min(-1)) exercise (p 0.05). In conclusion, it appears that greater parasympathetic modulation accounts for greater HRR following maximal exercise in boys versus men. Although submaximal HRR was greater in boys, parasympathetic responses were similar between groups.

  10. The effect of lifelong exercise dose on cardiovascular function during exercise

    Science.gov (United States)

    Carrick-Ranson, Graeme; Hastings, Jeffrey L.; Bhella, Paul S.; Fujimoto, Naoki; Shibata, Shigeki; Palmer, M. Dean; Boyd, Kara; Livingston, Sheryl; Dijk, Erika

    2014-01-01

    An increased “dose” of endurance exercise training is associated with a greater maximal oxygen uptake (V̇o2max), a larger left ventricular (LV) mass, and improved heart rate and blood pressure control. However, the effect of lifelong exercise dose on metabolic and hemodynamic response during exercise has not been previously examined. We performed a cross-sectional study on 101 (69 men) seniors (60 yr and older) focusing on lifelong exercise frequency as an index of exercise dose. These included 27 who had performed ≤2 exercise sessions/wk (sedentary), 25 who performed 2–3 sessions/wk (casual), 24 who performed 4–5 sessions/wk (committed) and 25 who performed ≥6 sessions/wk plus regular competitions (Masters athletes) over at least the last 25 yr. Oxygen uptake and hemodynamics [cardiac output, stroke volume (SV)] were collected at rest, two levels of steady-state submaximal exercise, and maximal exercise. Doppler ultrasound measures of LV diastolic filling were assessed at rest and during LV loading (saline infusion) to simulate increased LV filling. Body composition, total blood volume, and heart rate recovery after maximal exercise were also examined. V̇o2max increased in a dose-dependent manner (P exercise, cardiac output and SV were largest in committed exercisers and Masters athletes (P exercise, effective arterial elastance, an index of ventricular-arterial coupling, was lower in committed exercisers and Masters athletes (P exercise frequency. These data suggest that performing four or more weekly endurance exercise sessions over a lifetime results in significant gains in V̇o2max, SV, and heart rate regulation during exercise; however, improved SV regulation during exercise is not coupled with favorable effects on LV filling, even when the heart is fully loaded. PMID:24458750

  11. Reduced modulation of pain in older adults following isometric and aerobic exercise

    Science.gov (United States)

    Naugle, Kelly M.; Naugle, Keith E.; Riley, Joseph L.

    2016-01-01

    Laboratory based studies show that acute aerobic and isometric exercise reduces sensitivity to painful stimuli in young healthy individuals, indicative of a hypoalgesic response. However, little is known regarding the effect of aging on exercise-induced hypoalgesia (EIH). The purpose of this study was to examine age differences in EIH following submaximal isometric exercise, and moderate and vigorous aerobic exercise. Healthy older and younger adults completed one training session and four testing sessions consisting of either a submaximal isometric handgrip exercise, vigorous or moderate intensity stationary cycling, or quiet rest (control). The following measures were taken pre and post exercise/quiet rest: 1) pressure pain thresholds (PPTs), 2) suprathreshold pressure pain ratings, 3) pain ratings during 30-s of prolonged noxious heat stimulation, and 3) temporal summation of heat pain. The results revealed age differences in EIH following isometric and aerobic exercise, with younger adults experiencing greater EIH compared to older adults. The age differences in EIH varied across pain induction techniques and exercise type. These results provide evidence for abnormal pain modulation following acute exercise in older adults. PERSPECTIVE This article enhances our understanding of the influence of a single bout of exercise on pain sensitivity and perception in healthy older compared to younger adults. This knowledge could potentially help clinicians optimize exercise as a method of pain management. PMID:26993959

  12. Reduced Modulation of Pain in Older Adults After Isometric and Aerobic Exercise.

    Science.gov (United States)

    Naugle, Kelly M; Naugle, Keith E; Riley, Joseph L

    2016-06-01

    Laboratory-based studies show that acute aerobic and isometric exercise reduces sensitivity to painful stimuli in young healthy individuals, indicative of a hypoalgesic response. However, little is known regarding the effect of aging on exercise-induced hypoalgesia (EIH). The purpose of this study was to examine age differences in EIH after submaximal isometric exercise and moderate and vigorous aerobic exercise. Healthy older and younger adults completed 1 training session and 4 testing sessions consisting of a submaximal isometric handgrip exercise, vigorous or moderate intensity stationary cycling, or quiet rest (control). The following measures were taken before and after exercise/quiet rest: 1) pressure pain thresholds, 2) suprathreshold pressure pain ratings, 3) pain ratings during 30 seconds of prolonged noxious heat stimulation, and 4) temporal summation of heat pain. The results revealed age differences in EIH after isometric and aerobic exercise, with younger adults experiencing greater EIH compared with older adults. The age differences in EIH varied across pain induction techniques and exercise type. These results provide evidence for abnormal pain modulation after acute exercise in older adults. This article enhances our understanding of the influence of a single bout of exercise on pain sensitivity and perception in healthy older compared with younger adults. This knowledge could help clinicians optimize exercise as a method of pain management. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

  13. Effects of Pedal Speed and Crank Length on Pedaling Mechanics during Submaximal Cycling

    Science.gov (United States)

    BARRATT, PAUL RICHARD; MARTIN, JAMES C.; ELMER, STEVE J.; KORFF, THOMAS

    2016-01-01

    ABSTRACT During submaximal cycling, the neuromuscular system has the freedom to select different intermuscular coordination strategies. From both a basic science and an applied perspective, it is important to understand how the central nervous system adjusts pedaling mechanics in response to changes in pedaling conditions. Purpose To determine the effect of changes in pedal speed (a marker of muscle shortening velocity) and crank length (a marker of muscle length) on pedaling mechanics during submaximal cycling. Methods Fifteen trained cyclists performed submaximal isokinetic cycling trials (90 rpm, 240 W) using pedal speeds of 1.41 to 1.61 m·s−1 and crank lengths of 150 to 190 mm. Joint powers were calculated using inverse dynamics. Results Increases in pedal speed and crank length caused large increases knee and hip angular excursions and velocities (P 0.05). Joint moments and joint powers were less affected by changes in the independent variables, but some interesting effects and trends were observed. Most noteworthy, knee extension moments and powers tended to decrease, whereas hip extension power tended to increase with an increase in crank length. Conclusions The distribution of joint moments and powers is largely maintained across a range of pedaling conditions. The crank length induced differences in knee extension moments, and powers may represent a trade-off between the central nervous system’s attempts to simultaneously minimize muscle metabolic and mechanical stresses. These results increase our understanding of the neural and mechanical mechanisms underlying multi-joint task performance, and they have practical relevance to coaches, athletes, and clinicians. PMID:26559455

  14. Effects of pentoxifylline on hemorheologic alterations induced by incremental treadmill exercise in thoroughbreds.

    Science.gov (United States)

    Weiss, D J; Geor, R J; Burger, K

    1996-09-01

    To determine whether pentoxifylline treatment altered hematologic, rheologic, electrolyte, or blood gas test results of Thoroughbreds during submaximal treadmill exercise. 5 healthy Thoroughbreds that had raced within the past year and had no history of exercise-induced pulmonary hemorrhage. Mixed venous blood samples were obtained before exercise, at treadmill speeds of 9 and 13 m/s, and 20 minutes after exercise; hematologic, rheologic, electrolyte, and blood gas test results were determined. Pentoxifylline treatment resulted in a 45% reduction in RBC filtration pressures for horses at rest. The improved RBC filterability persisted during treadmill exercise. Horses treated with pentoxifylline had a greater decrease in Po2 values and a lesser increase in plasma lactate concentration during treadmill exercise. Administration of pentoxifylline improved RBC deformability of horses at rest and during treadmill exercise. Improved RBC deformability resulting from pentoxifylline treatment may reduce exercise-associated shear stress in pulmonary capillaries, thereby attenuating exercise-induced pulmonary hemorrhage.

  15. Effects of wheel and hand-rim size on submaximal propulsion in wheelchair athletes.

    Science.gov (United States)

    Mason, Barry S; Van Der Woude, Lucas H V; Tolfrey, Keith; Lenton, John P; Goosey-Tolfrey, Victoria L

    2012-01-01

    This study aimed to investigate the effects of fixed gear ratio wheel sizes on the physiological and biomechanical responses to submaximal wheelchair propulsion. Highly trained wheelchair basketball players (N = 13) propelled an adjustable sports wheelchair in three different wheel sizes (24, 25, and 26 inches) on a motor-driven treadmill. Each wheel was equipped with force-sensing hand-rims (SMARTWheel), which collected kinetic and temporal data. Oxygen uptake (V˙O2) and HR responses were measured with high-speed video footage collected to determine three-dimensional upper body joint kinematics. Mean power output and work per cycle decreased progressively with increasing wheel size (P wheelchair propulsion.

  16. Telemetry pill versus rectal and esophageal temperature during extreme rates of exercise-induced core temperature change

    NARCIS (Netherlands)

    Teunissen, L.P.J.; Haan, A. de; Koning, J.J. de; Daanen, H.A.M.

    2012-01-01

    Core temperature measurement with an ingestible telemetry pill has been scarcely investigated during extreme rates of temperature change, induced by short high-intensity exercise in the heat. Therefore, nine participants performed a protocol of rest, (sub)maximal cycling and recovery at 30 °C. The

  17. Effects of exercise in polluted air on the aerobic power, serum lactate level and cell blood count of active individuals

    Directory of Open Access Journals (Sweden)

    Mehdi Kargarfard

    2011-01-01

    Conclusions: Exercise in high-polluted air resulted in a significant reduction in the performance at submaximal levels of physical exertion. Therefore, the acute exposure to polluted air may cause a significant reduction in the performance of active individuals. The clinical importance of these findings should be assessed in longitudinal studies.

  18. Evaluation of an Exercise Field Test Using Heart Rate Monitors to Assess Cardiorespiratory Fitness and Heart Rate Recovery in an Asymptomatic Population

    OpenAIRE

    Coolbaugh, Crystal L; Anderson, Ivan B.; Wilson, Machelle D.; David A Hawkins; Amsterdam, Ezra A.

    2014-01-01

    PURPOSE: Measures of cardiorespiratory fitness (CRF) and heart rate recovery (HRR) can improve risk stratification for cardiovascular disease, but these measurements are rarely made in asymptomatic individuals due to cost. An exercise field test (EFT) to assess CRF and HRR would be an inexpensive method for cardiovascular disease risk assessment in large populations. This study assessed 1) the predictive accuracy of a 12-minute run/walk EFT for estimating CRF ([Formula: see text]) and 2) the ...

  19. Balance in single-limb stance in healthy subjects – reliability of testing procedure and the effect of short-duration sub-maximal cycling

    Directory of Open Access Journals (Sweden)

    Roberts David

    2003-06-01

    Full Text Available Abstract Background To assess balance in single-limb stance, center of pressure movements can be registered by stabilometry with force platforms. This can be used for evaluation of injuries to the lower extremities. It is important to ensure that the assessment tools we use in the clinical setting and in research have minimal measurement error. Previous studies have shown that the ability to maintain standing balance is decreased by fatiguing exercise. There is, however, a need for further studies regarding possible effects of general exercise on balance in single-limb stance. The aims of this study were: 1 to assess the test-retest reliability of balance variables measured in single-limb stance on a force platform, and 2 to study the effect of exercise on balance in single-limb stance, in healthy subjects. Methods Forty-two individuals were examined for test-retest reliability, and 24 individuals were tested before (pre-exercise and after (post-exercise short-duration, sub-maximal cycling. Amplitude and average speed of center of pressure movements were registered in the frontal and sagittal planes. Mean difference between test and retest with 95% confidence interval, the intraclass correlation coefficient, and the Bland and Altman graphs with limits of agreement, were used as statistical methods for assessing test-retest reliability. The paired t-test was used for comparisons between pre- and post-exercise measurements. Results No difference was found between test and retest. The intraclass correlation coefficients ranged from 0.79 to 0.95 in all stabilometric variables except one. The limits of agreement revealed that small changes in an individual's performance cannot be detected. Higher values were found after cycling in three of the eight stabilometric variables. Conclusions The absence of systematic variation and the high ICC values, indicate that the test is reliable for distinguishing among groups of subjects. However, relatively large

  20. Heterogeneous recruitment of quadriceps muscle portions and fibre types during moderate intensity knee-extensor exercise: effect of thigh occlusion

    DEFF Research Database (Denmark)

    Krustrup, Peter; Söderlund, Karin; Relu, Mihai U.

    2009-01-01

    The involvement of quadriceps femoris muscle portions and fibre type recruitment was studied during submaximal knee-extensor exercise without and with thigh occlusion (OCC) and compared with responses during intense exercise. Six healthy male subjects performed 90-s of moderate exercise without...... (MOD; 29+/-4 W) and with thigh OCC, and moderate exercise followed by 90-s of intense exercise (HI; 65+/-8 W). Temperatures were continuously measured in m. vastus lateralis (VL), vastus medialis (VM) and rectus femoris (RF) and successive muscle biopsies were obtained from VL. During MOD, muscle...

  1. Low-protein vegetarian diet does not have a short-term effect on blood acid–base status but raises oxygen consumption during submaximal cycling

    Directory of Open Access Journals (Sweden)

    Hietavala Enni-Maria

    2012-11-01

    Full Text Available Abstract Background Acid–base balance refers to the equilibrium between acids and bases in the human body. Nutrition may affect acid–base balance and further physical performance. With the help of PRAL (potential renal acid load, a low-protein vegetarian diet (LPVD was designed to enhance the production of bases in body. The aim of this study was to investigate if LPVD has an effect on blood acid–base status and performance during submaximal and maximal aerobic cycling. Methods Nine healthy, recreationally active men (age 23.5 ± 3.4 yr participated in the study and were randomly divided into two groups in a cross-over study design. Group 1 followed LPVD for 4 days and group 2 ate normally (ND before performing a cycle ergometer test. The test included three 10-min stages at 40, 60 and 80% of VO2max. The fourth stage was performed at 100% of VO2max until exhaustion. After 10–16 days, the groups started a second 4-day diet, and at the end performed the similar ergometer test. Venous blood samples were collected at the beginning and at the end of both diet periods and after every stage cycled. Results Diet caused no significant difference in venous blood pH, strong ion difference (SID, total concentration of weak acids (Atot, partial pressure of CO2 (pCO2 or HCO3- at rest or during cycling between LPVD and ND. In the LPVD group, at rest SID significantly increased over the diet period (38.6 ± 1.8 vs. 39.8 ± 0.9, p=0.009. Diet had no significant effect on exercise time to exhaustion, but VO2 was significantly higher at 40, 60 and 80% of VO2max after LPVD compared to ND (2.03 ± 0.25 vs. 1.82 ± 0.21 l/min, p=0.035; 2.86 ± 0.36 vs. 2.52 ± 0.33 l/min, p Conclusion There was no difference in venous blood acid–base status between a 4-day LPVD and ND. VO2 was increased during submaximal cycling after LPVD suggesting that the exercise economy was poorer. This had no further effect on maximal aerobic performance. More studies are needed to

  2. Exercise performance over the menstrual cycle in temperate and hot, humid conditions.

    Science.gov (United States)

    Janse DE Jonge, Xanne A K; Thompson, Martin W; Chuter, Vivienne H; Silk, Leslie N; Thom, Jeanette M

    2012-11-01

    This study investigated the effects of the menstrual cycle on prolonged exercise performance both in temperate (20°C, 45% relative humidity) and hot, humid (32°C, 60% relative humidity) conditions. For each environmental condition, 12 recreationally active females were tested during the early follicular (day 3-6) and midluteal (day 19-25) phases, verified by measurement of estradiol and progesterone. For all four tests, thermoregulatory, cardiorespiratory, and perceptual responses were measured during 60 min of exercise at 60% of maximal oxygen consumption followed by an incremental test to exhaustion. No differences in exercise performance between menstrual cycle phases were found during temperate conditions (n = 8) despite a higher resting and submaximal exercise core temperature (Tc) in the luteal phase. In hot, humid conditions (n = 8), however, prolonged exercise performance, as exercise time to fatigue, was significantly reduced during the luteal phase. This finding was not only accompanied by higher resting and submaximal exercise Tc but also a higher rate of increase in Tc during the luteal phase. Furthermore, submaximal exercise HR, minute ventilation, and RPE measures were higher during the luteal phase in hot, humid conditions. No significant differences were found over the menstrual cycle in heat loss responses (partitional calorimetry, sweat rate, upper arm sweat composition) and Tc at exhaustion. In temperate conditions, no changes in prolonged exercise performance were found over the menstrual cycle, whereas in hot, humid conditions, performance was decreased during the luteal phase. The combination of both exercise and heat stress with the elevated luteal phase Tc at the onset of exercise resulted in physiological and perceptual changes and a greater thermosensitivity, which may explain the decrease in performance.

  3. Effects of dietary Acid load on exercise metabolism and anaerobic exercise performance.

    Science.gov (United States)

    Caciano, Susan L; Inman, Cynthia L; Gockel-Blessing, Elizabeth E; Weiss, Edward P

    2015-06-01

    Dietary acid load, quantified as the potential renal acid load (PRAL) of the diet, affects systemic pH and acid-base regulation. In a previous cross-sectional study, we reported that a low dietary PRAL (i.e. alkaline promoting diet) is associated with higher respiratory exchange ratio (RER) values during maximal exercise. The purpose of the present study was to confirm the previous findings with a short-term dietary intervention study. Additionally, we sought to determine if changes in PRAL affects submaximal exercise RER (as a reflection of substrate utilization) and anaerobic exercise performance. Subjects underwent a graded treadmill exercise test (GXT) to exhaustion and an anaerobic exercise performance test on two occasions, once after following a low-PRAL diet and on a separate occasion, after a high-PRAL diet. The diets were continued as long as needed to achieve an alkaline or acid fasted morning urine pH, respectively, with all being 4-9 days in duration. RER was measured during the GXT with indirect calorimetry. The anaerobic performance test was a running time-to-exhaustion test lasting 1-4 min. Maximal exercise RER was lower in the low-PRAL trial compared to the high-PRAL trial (1.10 ± 0.02 vs. 1.20 ± 0.05, p = 0.037). The low-PRAL diet also resulted in a 21% greater time to exhaustion during anaerobic exercise (2.56 ± 0.36 vs. 2.11 ± 0.31 sec, p = 0.044) and a strong tendency for lower RER values during submaximal exercise at 70% VO2max (0.88 ± 0.02 vs. 0.96 ± 0.04, p = 0.060). Contrary to our expectations, a short-term low-PRAL (alkaline promoting) diet resulted in lower RER values during maximal-intensity exercise. However, the low-PRAL diet also increased anaerobic exercise time to exhaustion and appears to have shifted submaximal exercise substrate utilization to favor lipid oxidation and spare carbohydrate, both of which would be considered favorable effects in the context of exercise performance. Key pointsShort-term (4-9 days) changes in

  4. Dietary nitrate supplementation and exercise performance.

    Science.gov (United States)

    Jones, Andrew M

    2014-05-01

    Dietary nitrate is growing in popularity as a sports nutrition supplement. This article reviews the evidence base for the potential of inorganic nitrate to enhance sports and exercise performance. Inorganic nitrate is present in numerous foodstuffs and is abundant in green leafy vegetables and beetroot. Following ingestion, nitrate is converted in the body to nitrite and stored and circulated in the blood. In conditions of low oxygen availability, nitrite can be converted into nitric oxide, which is known to play a number of important roles in vascular and metabolic control. Dietary nitrate supplementation increases plasma nitrite concentration and reduces resting blood pressure. Intriguingly, nitrate supplementation also reduces the oxygen cost of submaximal exercise and can, in some circumstances, enhance exercise tolerance and performance. The mechanisms that may be responsible for these effects are reviewed and practical guidelines for safe and efficacious dietary nitrate supplementation are provided.

  5. Achilles tendinopathy alters stretch shortening cycle behaviour during a sub-maximal hopping task.

    Science.gov (United States)

    Debenham, James R; Travers, Mervyn J; Gibson, William; Campbell, Amity; Allison, Garry T

    2016-01-01

    To describe stretch shortening cycle behaviour of the ankle and lower limb in patients with Achilles tendinopathy (AT) and establish differences with healthy volunteers. Between-subjects case-controlled. Fifteen patients with AT (mean age 41.2±12.7 years) and 11 healthy volunteers (CON) (mean age 23.2±6.7 years) performed sub-maximal single-limb hopping on a custom built sledge-jump system. Using 3D motion analysis and surface EMG, temporal kinematic (lower limb stiffness, ankle angle at 80ms pre-contact, ankle angle at contact, peak ankle angle, ankle stretch amplitude) and EMG measures (onset, offset and peak times relative to contact) were captured. Data between AT and CON were compared statistically using a linear mixed model. Patients with AT exhibited significantly increased lower limb stiffness when compared to healthy volunteers (pbehaviour during sub-maximal hopping when compared with healthy volunteers. Patients with AT hop with greater lower limb stiffness, in a greater degree of ankle dorsiflexion and have a greater stretch amplitude. Likewise, delayed muscle activity is evident. These findings have implications in terms of informing the understanding of the pathoaetiology and management of AT. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  6. [Sub-maximal aerobic capacity and quality of life of patients with rheumatoid arthritis].

    Science.gov (United States)

    Lataoui, S; Belghali, S; Zeglaoui, H; Bouajina, E; Ben Saad, H

    2017-01-01

    Studies about sub-maximal aerobic capacity of patients with rheumatoid arthritis are scarce. To assess the sub-maximal aerobic capacity of these patients through the 6-min walk test, estimated age of the "muscular and cardiorespiratory" chain. Thirty-seven consecutive patients (aged 20 to 60 years) with newly diagnosed rheumatoid arthritis will be included. Non-inclusion criteria will be: use of drugs (e.g.; methotrexate, beta-blockers), orthopaedic or rheumatologic conditions (other than rheumatoid arthritis) that may alter walking ability and recent infections. Exclusion criteria will be: 6-min walking test contra-indications and imperfect performance of the required lung function and walking maneuvers. Signs of walking intolerance will be: test interruption, distance ≤lower limit of normal, dyspnea score ≥5/10 (visual analogue scale) at the end of the test, haemoglobin oxygen saturation (SpO2) drop ≥5%, cardiac frequency at the end of the test ≤60% of maximum predicted. An estimated "muscular and cardiorespiratory chain" age higher than the chronological one will be considered as a sign of accelerated ageing. A high percentage of patients suffering from rheumatoid arthritis would show evidences of walking limitation and accelerated "muscular and cardiorespiratory chain" ageing. There would be a significant correlation between the walking test and clinical, biological, radiological and pulmonary function data and the patients' quality-of-life status. Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  7. Impaired Muscle Oxygenation and Elevated Exercise Blood Pressure in Hypertensive Patients: Links With Vascular Stiffness.

    Science.gov (United States)

    Dipla, Konstantina; Triantafyllou, Areti; Koletsos, Nikolaos; Papadopoulos, Stavros; Sachpekidis, Vasileios; Vrabas, Ioannis S; Gkaliagkousi, Eugenia; Zafeiridis, Andreas; Douma, Stella

    2017-08-01

    This study examined in vivo (1) skeletal muscle oxygenation and microvascular function, at rest and during handgrip exercise, and (2) their association with macrovascular function and exercise blood pressure (BP), in newly diagnosed, never-treated patients with hypertension and normotensive individuals. Ninety-one individuals (51 hypertensives and 40 normotensives) underwent office and 24-hour ambulatory BP, arterial stiffness, and central aortic BP assessment, followed by a 5-minute arterial occlusion and a 3-minute submaximal handgrip exercise. Changes in muscle oxygenated and deoxygenated hemoglobin and tissue oxygen saturation were continuously monitored by near-infrared spectroscopy and beat-by-beat BP by Finapres. Hypertensives had higher (Pexercising at the same submaximal intensity, hypertensives required a significantly greater (Pexercise. © 2017 American Heart Association, Inc.

  8. Exercise thermoregulation with bed rest, confinement, and immersion deconditioning.

    Science.gov (United States)

    Greenleaf, J E

    1997-03-15

    Altered thermoregulation following exposure to prolonged (12-14 days) of bed rest and 6 hr of head-down thermoneutral water immersion in humans, and cage confinement (8 weeks) in male, mongrel dogs resulted in occasional increased core temperature (Tcore) at rest, but consistent "excessive" increase in Tcore during submaximal exercise. This excessive increase in Tcore in nonexercising and exercising subjects was independent of the mode (isometric or isotonic) of exercise training during bed rest, and was associated with the consistent hypovolemia in men but not in women taking estrogen supplementation (1.25 mg premarin/ day) which restored plasma volume during bed rest to ambulatory control levels. Post-bed rest exercise sweating (evaporative heat loss) was unchanged or higher than control levels; however, calculated tissue heat conductance was significantly lower in men, and forearm venoconstriction was greater (venous volume was reduced) in women during exercise after bed rest. Because sweating appeared proportional to the increased level of Tcore, these findings suggest that one major factor for the excessive hyperthermia is decreased core to periphery heat conduction. Exercising dogs respond like humans with excessive increase in both rectal (Tre) and exercising muscle temperatures (Tmu) after confinement and, after eight weeks of exercise training on a treadmill following confinement, they had an attenuated rate of increase of Tre even below ambulatory control levels. Intravenous infusion of glucose also attenuated not only the rise in Tre during exercise in normal dogs, but also the excessive rise in Tre and exercising Tmu after confinement. Oral glucose also appeared to reduce the rate of increase in excessive Tre in men after immersion deconditioning. There was a greater rate of rise in Tcore in two cosmonauts during supine submaximal exercise (65% VO2 max) on the fifth recovery day after the 115-day Mir 18 mission. Thus, the excessive rise in core

  9. Exercise thermoregulation with bed rest, confinement, and immersion deconditioning

    Science.gov (United States)

    Greenleaf, J. E.

    1997-01-01

    Altered thermoregulation following exposure to prolonged (12-14 days) of bed rest and 6 hr of head-down thermoneutral water immersion in humans, and cage confinement (8 weeks) in male, mongrel dogs resulted in occasional increased core temperature (Tcore) at rest, but consistent "excessive" increase in Tcore during submaximal exercise. This excessive increase in Tcore in nonexercising and exercising subjects was independent of the mode (isometric or isotonic) of exercise training during bed rest, and was associated with the consistent hypovolemia in men but not in women taking estrogen supplementation (1.25 mg premarin/ day) which restored plasma volume during bed rest to ambulatory control levels. Post-bed rest exercise sweating (evaporative heat loss) was unchanged or higher than control levels; however, calculated tissue heat conductance was significantly lower in men, and forearm venoconstriction was greater (venous volume was reduced) in women during exercise after bed rest. Because sweating appeared proportional to the increased level of Tcore, these findings suggest that one major factor for the excessive hyperthermia is decreased core to periphery heat conduction. Exercising dogs respond like humans with excessive increase in both rectal (Tre) and exercising muscle temperatures (Tmu) after confinement and, after eight weeks of exercise training on a treadmill following confinement, they had an attenuated rate of increase of Tre even below ambulatory control levels. Intravenous infusion of glucose also attenuated not only the rise in Tre during exercise in normal dogs, but also the excessive rise in Tre and exercising Tmu after confinement. Oral glucose also appeared to reduce the rate of increase in excessive Tre in men after immersion deconditioning. There was a greater rate of rise in Tcore in two cosmonauts during supine submaximal exercise (65% VO2 max) on the fifth recovery day after the 115-day Mir 18 mission. Thus, the excessive rise in core

  10. Impact of a Submaximal Warm-Up on Endurance Performance in Highly Trained and Competitive Male Runners

    Science.gov (United States)

    Zourdos, Michael C.; Bazyler, Caleb D.; Jo, Edward; Khamoui, Andy V.; Park, Bong-Sup; Lee, Sang-Rok; Panton, Lynn B.; Kim, Jeong-Su

    2017-01-01

    Purpose: The purpose of this investigation was to examine the effects of a submaximal running warm-up on running performance in male endurance athletes (n = 16, M[subscript age] = 21 ± 2 years, M[subscript VO2max] = 69.3 ± 5.1 mL/kg/min). Method: Endurance performance was determined by a 30-min distance trial after control and submaximal running…

  11. Towards real-time eruption forecasting in the Auckland Volcanic Field: application of BET_EF during the New Zealand National Disaster Exercise `Ruaumoko'

    Science.gov (United States)

    Lindsay, Jan; Marzocchi, Warner; Jolly, Gill; Constantinescu, Robert; Selva, Jacopo; Sandri, Laura

    2010-03-01

    The Auckland Volcanic Field (AVF) is a young basaltic field that lies beneath the urban area of Auckland, New Zealand’s largest city. Over the past 250,000 years the AVF has produced at least 49 basaltic centers; the last eruption was only 600 years ago. In recognition of the high risk associated with a possible future eruption in Auckland, the New Zealand government ran Exercise Ruaumoko in March 2008, a test of New Zealand’s nation-wide preparedness for responding to a major disaster resulting from a volcanic eruption in Auckland City. The exercise scenario was developed in secret, and covered the period of precursory activity up until the eruption. During Exercise Ruaumoko we adapted a recently developed statistical code for eruption forecasting, namely BET_EF (Bayesian Event Tree for Eruption Forecasting), to independently track the unrest evolution and to forecast the most likely onset time, location and style of the initial phase of the simulated eruption. The code was set up before the start of the exercise by entering reliable information on the past history of the AVF as well as the monitoring signals expected in the event of magmatic unrest and an impending eruption. The average probabilities calculated by BET_EF during Exercise Ruaumoko corresponded well to the probabilities subjectively (and independently) estimated by the advising scientists (differences of few percentage units), and provided a sound forecast of the timing (before the event, the eruption probability reached 90%) and location of the eruption. This application of BET_EF to a volcanic field that has experienced no historical activity and for which otherwise limited prior information is available shows its versatility and potential usefulness as a tool to aid decision-making for a wide range of volcano types. Our near real-time application of BET_EF during Exercise Ruaumoko highlighted its potential to clarify and possibly optimize decision-making procedures in a future AVF eruption

  12. Cold exposure enhances fat utilization but not non-esterified fatty acids, glycerol or catecholamines availability during submaximal walking and running.

    Science.gov (United States)

    Gagnon, Dominique D; Rintamäki, Hannu; Gagnon, Sheila S; Cheung, Stephen S; Herzig, Karl-Heinz; Porvari, Katja; Kyröläinen, Heikki

    2013-01-01

    Cold exposure modulates the use of carbohydrates (CHOs) and fat during exercise. This phenomenon has mostly been observed in controlled cycling studies, but not during walking and running when core temperature and oxygen consumption are controlled, as both may alter energy metabolism. This study aimed at examining energy substrate availability and utilization during walking and running in the cold when core temperature and oxygen consumption are maintained. Ten lightly clothed male subjects walked or ran for 60-min, at 50% and 70% of maximal oxygen consumption, respectively, in a climatic chamber set at 0°C or 22°C. Thermal, cardiovascular, and oxidative responses were measured every 15-min during exercise. Blood samples for serum non-esterified fatty acids (NEFAs), glycerol, glucose, beta-hydroxybutyrate (BHB), plasma catecholamines, and serum lipids were collected immediately prior, and at 30- and 60-min of exercise. Skin temperature strongly decreased while core temperature did not change during cold trials. Heart rate (HR) was also lower in cold trials. A rise in fat utilization in the cold was seen through lower respiratory quotient (RQ) (-0.03 ± 0.02), greater fat oxidation (+0.14 ± 0.13 g · min(-1)) and contribution of fat to total energy expenditure (+1.62 ± 1.99 kcal · min(-1)). No differences from cold exposure were observed in blood parameters. During submaximal walking and running, a greater reliance on derived fat sources occurs in the cold, despite the absence of concurrent alterations in NEFAs, glycerol, or catecholamine concentrations. This disparity may suggest a greater reliance on intra-muscular energy sources such as triglycerides during both walking and running.

  13. Cold exposure enhances fat utilization but not non-esterified fatty acids, glycerol or catecholamines availability during submaximal walking and running

    Directory of Open Access Journals (Sweden)

    Dominique Daniel Gagnon

    2013-05-01

    Full Text Available Cold exposure modulates the use of carbohydrates and fat during exercise. This phenomenon has mostly been observed in controlled cycling studies, but not during walking and running when core temperature and oxygen consumption are controlled, as both may alter energy metabolism. This study aimed at examining energy substrate availability and utilization during walking and running in the cold when core temperature and oxygen consumption are maintained. Ten lightly clothed male subjects walked or ran for 60-min, at 50% and 70% of maximal oxygen consumption, respectively, in a climatic chamber set at 0°C or 22°C. Thermal, cardiovascular, and oxidative responses were measured every 15-min during exercise. Blood samples for serum non-esterified fatty acids, glycerol, glucose, beta-hydroxybutyrate, plasma catecholamines, and serum lipids were collected immediately prior, and at 30- and 60-min of exercise. Skin temperature strongly decreased while core temperature did not change during cold trials. Heart rate was also lower in cold trials. A rise in fat utilization in the cold was seen through lower respiratory quotient (-0.03 ± 0.02, greater fat oxidation (+0.14 ± 0.13 g•min-1 and contribution of fat to total energy expenditure (+1.62 ± 1.99 kcal•min-1. No differences from cold exposure were observed in blood parameters. During submaximal walking and running, a greater reliance on derived fat sources occurs in the cold, despite the absence of concurrent alterations in non-esterified fatty acids, glycerol, or catecholamine concentrations. This disparity may suggest a greater reliance on intra-muscular energy sources such as triglycerides during both walking and running.

  14. Non-exercise estimation of VO2max using the International Physical Activity Questionnaire

    Science.gov (United States)

    Schembre, Susan M.; Riebe, Deborah A.

    2011-01-01

    Non-exercise equations developed from self-reported physical activity can estimate maximal oxygen uptake (VO2max) as well as submaximal exercise testing. The International Physical Activity Questionnaire (IPAQ) is the most widely used and validated self-report measure of physical activity. This study aimed to develop and test a VO2max estimation equation derived from the IPAQ-Short Form (IPAQ-S). College-aged males and females (n = 80) completed the IPAQ-S and performed a maximal exercise test. The estimation equation was created with multivariate regression in a gender-balanced subsample of participants, equally representing five levels of fitness (n = 50) and validated in the remaining participants (n = 30). The resulting equation explained 43% of the variance in measured VO2max (SEE = 5.45 ml·kg-1·min-1). Estimated VO2max for 87% of individuals fell within acceptable limits of error observed with submaximal exercise testing (20% error). The IPAQ-S can be used to successfully estimate VO2max as well as submaximal exercise tests. Development of other population-specific estimation equations is warranted. PMID:21927551

  15. Relations of self-regulation and self-efficacy for exercise and eating and BMI change: A field investigation

    Directory of Open Access Journals (Sweden)

    Annesi James J

    2010-09-01

    Full Text Available Abstract Objectives This study aimed to assess relations of self-regulatory skill use with self-efficacy for exercise and appropriate eating, and the resulting change in weight associated with participation in a nutrition and exercise treatment supported by cognitive-behavioral methods. Methods Adults with severe obesity (N = 95; mean BMI = 40.5 ± 3.9 kg/m2 participated in a 6-month exercise and nutrition treatment emphasizing self-regulatory skills. Changes in self-regulatory skills usage, self-efficacy, overall mood, and BMI were measured. Relations of changes in self-regulatory skill use and self-efficacy, for both physical activity and appropriate eating, were assessed, as was the possibility of mood change being a mediator of these relationships. Indirect effects of the variables associated with the present treatment on BMI change were then estimated. Results For both exercise and appropriate eating, changes in self-regulation were associated with self-efficacy change. Mood change partially mediated the relationship between changes in self-regulation for appropriate eating and self-efficacy for appropriate eating. Self-efficacy changes for physical activity and controlled eating, together, explained a significant portion of the variance in BMI change (R2 = 0.26, p Conclusion Findings suggest that training in self-regulation for exercise and eating may benefit self-efficacy and weight-loss outcomes. Thus, these variables should be considered in both the theory and behavioral treatment of obesity.

  16. Special Needs to Prescribe Exercise Intensity for Scientific Studies

    Directory of Open Access Journals (Sweden)

    Peter Hofmann

    2011-01-01

    exercise training. A wide range of intensities is used to prescribe exercise, but this approach is limited. Usually percentages of maximal oxygen uptake (VO2 or heart rate (HR are applied to set exercise training intensity but this approach yields substantially variable metabolic and cardiocirculatory responses. Heterogeneous acute responses and training effects are explained by the nonuniform heart rate performance curve during incremental exercise which significantly alters the calculations of %HRmax and %HRR target HR data. Similar limitations hold true for using %VO2max and %VO2R. The solution of these shortcomings is to strictly apply objective submaximal markers such as thresholds or turn points and to tailor exercise training within defined regions.

  17. Exercise thermoregulation in men after 6 hours of immersion

    Science.gov (United States)

    Greenleaf, J. E.; Spaul, W. A.; Kravik, S. E.; Wong, N.; Elder, C. A.

    1985-01-01

    The present investigation is concerned with thermoregulation at rest and during exercise after water-immersion deconditioning, giving particular attention to the effects of fluid shifts and negative water balance on sweat rate and rectal temperature. Six healthy males 20-35 years old were used in the experiments. Rectal and mean skin temperature, skin heat conductance, heart rate, and total body sweat rate were measured during 70 min of supine leg exercise at 50 percent of peak O2 uptake. The data were taken after a 6-h control period in air and after immersion to the neck in water (34.5 C) for 6 h after overnight food and fluid restriction. Attention is given to end exercise heart rates and data during exercise. The obtained results suggest that, compared with control responses, the equilibrium level of core temperature during submaximal exercise is regulated at a higher level after immersion.

  18. Prevention: Exercise

    Medline Plus

    Full Text Available ... Smoking Weight Patient Safety Exercise Strengthening Strengthen Your Core! Stretching/Flexibility Aerobic Exercise Cervical Exercise Strength Training for the Elderly Other Back Pack Safety ...

  19. Impact of menstrual cycle phase on the exercise status of young, sedentary women.

    Science.gov (United States)

    Redman, Leanne M; Scroop, Garry C; Norman, Robert J

    2003-11-01

    The purpose of the present study was to compare exercise status during the follicular (FP) and luteal (LP) phases of the menstrual cycle of a single group of young, sedentary women, where the marked differential in the blood concentrations of 17beta-oestradiol ([E(2)]) and progesterone ([P(4)]) has the potential to alter the metabolic response to exercise. Fourteen females [21.8 (4.0) years, peak oxygen uptake ( VO(2peak)) cycle ergometer exercise while measurements were made of several metabolic and hormonal variables. With the incremental exercise test, time to exhaustion, maximal power output and total work done were not different between the two phases, nor were the absolute values for VO(2peak) or the corresponding values for ventilation ( VE), respiratory frequency ( f(R)) and heart rate (HR). Resting, end-exercise and peak (post-exercise) plasma lactate concentrations and the lactate threshold were not different between the two phases either. However, as the workloads increased during the incremental protocol, plasma lactate concentration, carbon dioxide output ( VCO(2)) and the respiratory exchange ratio (RER) all were lower during LP, while oxygen uptake ( VO(2)) was higher. With steady-state submaximal exercise, at workloads corresponding to 25% and 75% of menstrual cycle phase-specific VO(2peak), VO(2) and the oxygen pulse ( VO(2)/HR) were higher and RER and plasma lactate concentration lower during LP. Regardless of phase, [E(2)] increased with both incremental and steady-state submaximal exercise, while [P(4)] was unchanged. It is concluded that while exercise capacity, as defined by VO(2peak) and the lactate threshold, is unaffected by cycle phase in young, sedentary women, the metabolic responses in the LP during both incremental and steady-state submaximal exercise suggest a greater dependence on fat as an energy source.

  20. Effects of prior exercise on the action of insulin-like growth factor I in skeletal muscle

    Science.gov (United States)

    Henriksen, E. J.; Louters, L. L.; Stump, C. S.; Tipton, C. M.

    1992-01-01

    Prior exercise increases insulin sensitivity for glucose and system A neutral amino acid transport activities in skeletal muscle. Insulin-like growth factor I (IGF-I) also activates these transport processes in resting muscle. It is not known, however, whether prior exercise increases IGF-I action in muscle. Therefore we determined the effect of a single exhausting bout of swim exercise on IGF-I-stimulated glucose transport activity [assessed by 2-deoxy-D-glucose (2-DG) uptake] and system A activity [assessed by alpha-(methylamino)isobutyric acid (MeAIB) uptake] in the isolated rat epitrochlearis muscle. When measured 3.5 h after exercise, the responses to a submaximal concentration (0.2 nM), but not a maximal concentration (13.3 nM), of insulin for activation of 2-DG uptake and MeAIB uptake were enhanced. In contrast, prior exercise increased markedly both the submaximal (5 nM) and maximal (20 nM) responses to IGF-I for activation of 2-DG uptake, whereas only the submaximal response to IGF-I (3 nM) for MeAIB uptake was enhanced after exercise. We conclude that 1) prior exercise significantly enhances the response to a submaximal concentration of IGF-I for activation of the glucose transport and system A neutral amino acid transport systems in skeletal muscle and 2) the enhanced maximal response for IGF-I action after exercise is restricted to the signaling pathway for activation of the glucose transport system.

  1. The Role of Field Exercises in Ecological Learning and Values Education: Action Research on the Use of Campus Wetlands

    Science.gov (United States)

    Sukhontapatipak, Chutamas; Srikosamatara, Sompoad

    2012-01-01

    Providing undergraduate biology students with ecological knowledge and environmental awareness is critical for developing professionalism in sustainable development. In addition to the cognitive and psychomotor development, outdoor ecological exercises combining place-based education and experiential learning can stimulate the affective domain of…

  2. The using of the track-and-field exercises in the process of formation of sport style of life of children of junior education

    Directory of Open Access Journals (Sweden)

    Frolova N.A.

    2010-04-01

    Full Text Available The problem of application of track-and-field exercises is lighted up for the decision of tasks of forming of sporting lifestyle junior schoolboys. The analysis of scientific literature is conducted on marked issue. Facilities of track-and-field have a wide spectrum of operating on an organism. They render assistance to the decision of health, educate and educational tasks in the process of physical education. Also form basis for mastering of maintenance of school on-line tutorial. It is well-proven that the use of facilities of track-and-field is rendered by an assistance initial sporting preparation of children in the conditions of general school.

  3. Cycling on rollers: Kreitler fan resistance at submaximal levels of effort.

    Science.gov (United States)

    Reiser, R F; Hart, C R

    2008-03-01

    The goal of this investigation was to characterize the commercially available fan unit for the KreitlerAlloy rollers at submaximal levels of effort (cyclist rode six times at each of three fan inlet settings (closed, half, and full open) and five fan speeds (900, 1800, 2700, 3600, and 4500 rpm). Fan power requirements were isolated by subtracting roller resistance from separate trials. Power requirements relative to fan inlet and fan speed possessed a significant interaction with the main effects for each also significant (all p or = 0.997). Fan resistance was virtually non existent at 900 rpm. Fan resistance then significantly increased with increasing fan speed and inlet opening. At 4500 rpm power requirements of the fan reached 269 +/- 6, 352 +/- 7, and 406 +/- 9 W with the inlet closed, half, and fully open, respectively (p training and testing environments.

  4. The effect of short-duration sub-maximal cycling on balance in single-limb stance in patients with anterior cruciate ligament injury: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Roberts David

    2004-11-01

    Full Text Available Abstract Background It has previously been shown that an anterior cruciate ligament (ACL injury may lead to impaired postural control, and that the ability to maintain postural control is decreased by fatigue in healthy subjects. To our knowledge, no studies have reported the effect of fatigue on postural control in subjects with ACL injury. This study was aimed at examining the effect of fatigue on balance in single-limb stance in subjects with ACL injury, and to compare the effects, and the ability to maintain balance, with that of a control group of uninjured subjects. Methods Thirty-six patients with unilateral, non-operated, non-acute ACL injury, and 24 uninjured subjects were examined with stabilometry before (pre-exercise and immediately after (post-exercise short-duration, sub-maximal cycling. In addition, the post-exercise measurements were compared, to evaluate the instantaneous ability to maintain balance and any possible recovery. The amplitude and average speed of center of pressure movements were registered in the frontal and sagittal planes. The paired t-test was used for the intra-group comparisons, and the independent t-test for the inter-group comparisons, with Bonferroni correction for multiple comparisons. Results No differences were found in the effects of exercise between the patients and the controls. Analysis of the post-exercise measurements revealed greater effects or a tendency towards greater effects on the injured leg than in the control group. The average speed was lower among the patients than in the control group. Conclusions The results of the present study showed no differences in the effects of exercise between the patients and the controls. However, the patients seemed to react differently regarding ability to maintain balance in single-limb stance directly after exercise than the control group. The lower average speed among the patients may be an expression of different neuromuscular adaptive strategies than

  5. Muscle vibration sustains motor unit firing rate during submaximal isometric fatigue in humans.

    Science.gov (United States)

    Griffin, L; Garland, S J; Ivanova, T; Gossen, E R

    2001-09-15

    1. In keeping with the 'muscular wisdom hypothesis', many studies have documented that the firing rate of the majority of motor units decreased during fatiguing isometric contractions. The present study investigated whether the application of periodic muscle vibration, which strongly activates muscle spindles, would alter the modulation of motor unit firing rate during submaximal fatiguing isometric contractions. 2. Thirty-three motor units from the lateral head of the triceps brachii muscle were recorded from 10 subjects during a sustained isometric 20 % maximal voluntary contraction (MVC) of the elbow extensors. Vibration was interposed on the contraction for 2 s every 10 s. Twenty-two motor units were recorded from the beginning of the fatigue task. The discharge rate of the majority of motor units remained constant (12/22) or increased (4/22) with fatigue. Six motor units demonstrated a reduction in discharge rate that later returned toward initial values; these motor units had higher initial discharge rates than the other 16 motor units. 3. In a second series of experiments, four subjects held a sustained isometric 20 % MVC for 2 min and then vibration was applied as above for the remainder of the contraction. In this case, motor units initially demonstrated a decrease in firing rate that increased after the vibration was applied. Thus muscle spindle disfacilitation of the motoneurone pool may be associated with the decline of motor unit discharge rate observed during the first 2 min of the contraction. 4. In a third set of experiments, seven subjects performed the main experiment on one occasion and repeated the fatigue task without vibration on a second occasion. Neither the endurance time of the fatiguing contraction nor the MVC torque following fatigue was affected by the application of vibration. This finding calls into question the applicability of the muscular wisdom hypothesis to submaximal contractions.

  6. Reciprocal effects of treatment-induced increases in exercise and improved eating, and their psychosocial correlates, in obese adults seeking weight loss: a field-based trial

    OpenAIRE

    Annesi, James J.; Porter, Kandice J

    2013-01-01

    Background A better understanding of interrelations of exercise and improved eating, and their psychosocial correlates of self-efficacy, mood, and self-regulation, may be useful for the architecture of improved weight loss treatments. Theory-based research within field settings, with samples possessing high probabilities of health risks, might enable rapid application of useful findings. Methods Adult volunteers with severe obesity (body mass index [BMI] 35–50 kg/m2; age = 43.0 ± 9.5 y; 83% f...

  7. Skeletal muscle metabolism during prolonged exercise in Pompe disease

    Directory of Open Access Journals (Sweden)

    Nicolai Preisler

    2017-07-01

    Full Text Available Objective: Pompe disease (glycogenosis type II is caused by lysosomal alpha-glucosidase deficiency, which leads to a block in intra-lysosomal glycogen breakdown. In spite of enzyme replacement therapy, Pompe disease continues to be a progressive metabolic myopathy. Considering the health benefits of exercise, it is important in Pompe disease to acquire more information about muscle substrate use during exercise. Methods: Seven adults with Pompe disease were matched to a healthy control group (1:1. We determined (1 peak oxidative capacity (VO2peak and (2 carbohydrate and fatty acid metabolism during submaximal exercise (33 W for 1 h, using cycle-ergometer exercise, indirect calorimetry and stable isotopes. Results: In the patients, VO2peak was less than half of average control values; mean difference −1659 mL/min (CI: −2450 to −867, P = 0.001. However, the respiratory exchange ratio increased to >1.0 and lactate levels rose 5-fold in the patients, indicating significant glycolytic flux. In line with this, during submaximal exercise, the rates of oxidation (ROX of carbohydrates and palmitate were similar between patients and controls (mean difference 0.226 g/min (CI: 0.611 to −0.078, P = 0.318 and mean difference 0.016 μmol/kg/min (CI: 1.287 to −1.255, P = 0.710, respectively. Conclusion: Reflecting muscle weakness and wasting, Pompe disease is associated with markedly reduced maximal exercise capacity. However, glycogenolysis is not impaired in exercise. Unlike in other metabolic myopathies, skeletal muscle substrate use during exercise is normal in Pompe disease rendering exercise less complicated for e.g. medical or recreational purposes.

  8. Skeletal muscle metabolism during prolonged exercise in Pompe disease.

    Science.gov (United States)

    Preisler, Nicolai; Laforêt, Pascal; Madsen, Karen Lindhardt; Husu, Edith; Vissing, Christoffer Rasmus; Hedermann, Gitte; Galbo, Henrik; Lindberg, Christopher; Vissing, John

    2017-08-01

    Pompe disease (glycogenosis type II) is caused by lysosomal alpha-glucosidase deficiency, which leads to a block in intra-lysosomal glycogen breakdown. In spite of enzyme replacement therapy, Pompe disease continues to be a progressive metabolic myopathy. Considering the health benefits of exercise, it is important in Pompe disease to acquire more information about muscle substrate use during exercise. Seven adults with Pompe disease were matched to a healthy control group (1:1). We determined (1) peak oxidative capacity (VO2peak) and (2) carbohydrate and fatty acid metabolism during submaximal exercise (33 W) for 1 h, using cycle-ergometer exercise, indirect calorimetry and stable isotopes. In the patients, VO2peak was less than half of average control values; mean difference -1659 mL/min (CI: -2450 to -867, P = 0.001). However, the respiratory exchange ratio increased to >1.0 and lactate levels rose 5-fold in the patients, indicating significant glycolytic flux. In line with this, during submaximal exercise, the rates of oxidation (ROX) of carbohydrates and palmitate were similar between patients and controls (mean difference 0.226 g/min (CI: 0.611 to -0.078, P = 0.318) and mean difference 0.016 µmol/kg/min (CI: 1.287 to -1.255, P = 0.710), respectively). Reflecting muscle weakness and wasting, Pompe disease is associated with markedly reduced maximal exercise capacity. However, glycogenolysis is not impaired in exercise. Unlike in other metabolic myopathies, skeletal muscle substrate use during exercise is normal in Pompe disease rendering exercise less complicated for e.g. medical or recreational purposes. © 2017 The authors.

  9. Disproportional changes in hematocrit, plasma volume, and proteins during exercise and bed rest.

    Science.gov (United States)

    Van Beaumont, W.; Greenleaf, J. E.; Juhos, L.

    1972-01-01

    The interrelationships between the changes in plasma volume, hematocrit, and plasma proteins during muscular exercise and bed rest were investigated. Proportionally, the changes in hematocrit are always smaller than the changes in plasma volume. For this reason changes in the concentration of blood constituents can only be quantitated on the basis of plasma volume changes. During short periods of intensive exercise, there was a small loss of plasma proteins. With prolonged submaximal exercise there was a net gain in plasma protein, which contributes to stabilization of the vascular volume. Prolonged bed rest induced hypoproteinemia; this loss of plasma protein probably plays an important role in recumbency hypovolemia.

  10. Exhaled nitric oxide predicts exercise-induced bronchoconstriction in asthmatic school children

    DEFF Research Database (Denmark)

    Buchvald, Frederik; Hermansen, Mette N; Nielsen, Kim G

    2005-01-01

    to a standardized submaximal exercise test on the treadmill were measured in 111 school children with asthma. EIB could be excluded with a probability of 90% in asthmatic children with FeNO levels ... reducing the need for exercise testing. OBJECTIVE: The aim of this study was to estimate the value of FeNO as a predictor of EIB in asthmatic children. METHODS: Stable outpatient asthmatic school children performed standard exercise challenge tests and measurement of FeNO. RESULTS: FeNO and response...

  11. A Low-Glycemic Diet Lifestyle Intervention Improves Fat Utilization during Exercise in Older Obese Humans

    DEFF Research Database (Denmark)

    Solomon, Thomas; Haus, Jacob M; Cook, Marc A

    2013-01-01

    Objective: To determine the influence of dietary glycemic index on exercise training-induced adaptations in substrate oxidation in obesity. Design and Methods: Twenty older, obese individuals undertook 3 months of fully supervised aerobic exercise and were randomized to low- (LoGIX) or high......-glycemic (HiGIX) diets. Changes in indirect calorimetry (VO2 ; VCO2 ) were assessed at rest, during a hyperinsulinemic-euglycemic clamp, and during submaximal exercise (walking: 65% VO2 max, 200 kcal energy expenditure). Intramyocellular lipid (IMCL) was measured by (1) H-magnetic resonance spectroscopy...

  12. Eccentric exercise decreases maximal insulin action in humans

    DEFF Research Database (Denmark)

    Asp, Svend; Daugaard, J R; Kristiansen, S

    1996-01-01

    ) necessary to maintain euglycaemia during maximal insulin stimulation was lower during PEC compared with CC (15.7%, 81.3 +/- 3.2 vs. 96.4 +/- 8.8 mumol kg-1 min-1, P 2 days after unaccustomed eccentric exercise, muscle and whole-body insulin action is impaired at maximal...... subjects participated in two euglycaemic clamps, performed in random order. One clamp was preceded 2 days earlier by one-legged eccentric exercise (post-eccentric exercise clamp (PEC)) and one was without the prior exercise (control clamp (CC)). 2. During PEC the maximal insulin-stimulated glucose uptake...... over the eccentric thigh was marginally lower when compared with the control thigh, (11.9%, 64.6 +/- 10.3 vs. 73.3 +/- 10.2 mumol kg-1 min-1, P = 0.08), whereas no inter-thigh difference was observed at a submaximal insulin concentration. The glycogen concentration was lower in the eccentric thigh...

  13. Regadenoson in Europe: first-year experience of regadenoson stress combined with submaximal exercise in patients undergoing myocardial perfusion scintigraphy

    OpenAIRE

    Brinkert, M.; Reyes, E.; Walker, S.; Latus, K.; Maenhout, A.; Mizumoto, R.; Nkomo, C.; Standbridge, K.; Wechalekar, K.; Underwood, S. R.

    2013-01-01

    Purpose Regadenoson was approved for clinical use in Europe in 2011. Since then, it has become the default form of stress at our institution. We have assessed the side-effect profile and tolerability of regadenoson in patients undergoing clinically indicated myocardial perfusion scintigraphy between July 2011 and July 2012. Methods Clinical, stress and imaging data were recorded prospectively. Symptoms during stress were recorded and defined as mild, moderate or severe. An adverse event was d...

  14. Differential glucose uptake in quadriceps and other leg muscles during one-legged dynamic submaximal knee-extension exercise

    DEFF Research Database (Denmark)

    Kalliokoski, Kari K; Boushel, Robert; Langberg, Henning

    2011-01-01

    to mean GU in QF (=100%), GU was on average 73% in VL, 84% in rectus femoris, 115% in vastus medialis, and 142% in VI. Variable activation of hamstring muscles and muscles of the lower leg was also observed. These results show that GU of different muscles of quadriceps muscle group as well as between...

  15. Basic science behind the cardiovascular benefits of exercise.

    Science.gov (United States)

    Wilson, Mathew G; Ellison, Georgina M; Cable, N Tim

    2016-01-01

    Cardiorespiratory fitness is a strong predictor of cardiovascular (CV) disease and all-cause mortality, with increases in cardiorespiratory fitness associated with corresponding decreases in CV disease risk. The effects of exercise upon the myocardium and vascular system are dependent upon the frequency, intensity and duration of the exercise itself. Following a prolonged period (≥6 months) of regular intensive exercise in previously untrained individuals, resting and submaximal exercising heart rates are typically 5-20 beats lower, with an increase in stroke volume of ∼20% and enhanced myocardial contractility. Structurally, all four heart chambers increase in volume with mild increases in wall thickness, resulting in greater cardiac mass due to increased myocardial cell size. With this in mind, the present paper aims to review the basic science behind the CV benefits of exercise. Attention will be paid to understanding (1) the relationship between exercise and cardiac remodelling; (2) the cardiac cellular and molecular adaptations in response to exercise, including the examination of molecular mechanisms of physiological cardiac growth and applying these mechanisms to identify new therapeutic targets to prevent or reverse pathological remodelling and heart failure; and (3) vascular adaptations in response to exercise. Finally, this review will briefly examine how to optimise the CV benefits of exercise by considering how much and how intense exercise should be. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  16. Walking tests during the exercise training: Specific use for the cardiac rehabilitation

    OpenAIRE

    Casillas, J.-M.; Hannequin, A.; Besson, D.; Benaïm, S.; Krawcow, C.; Laurent, Y.; Gremeaux, V.

    2013-01-01

    International audience; Walk tests, principally the six-minute walk test (6mWT), constitute a safe, useful submaximal tool for exercise tolerance testing in cardiac rehabilitation (CR). The 6mWT result reflects functional status, walking autonomy and efficacy of CR on walking endurance, which is more pronounced in patients with low functional capacity (heart failure - cardiac surgery). The 6mWT result is a strong predictor of mortality. However, clinically significant changes and reliability ...

  17. Effects of reducing exposure to air pollution on submaximal cardiopulmonary test in patients with heart failure: Analysis of the randomized, double-blind and controlled FILTER-HF trial.

    Science.gov (United States)

    Vieira, Jefferson L; Guimaraes, Guilherme V; de Andre, Paulo A; Saldiva, Paulo H Nascimento; Bocchi, Edimar A

    2016-07-15

    Air pollution exposure could mitigate the health benefits of exercise in patients with heart failure (HF). We tested the effects of a respiratory filter on HF patients exposed to air pollution during exercise. Ancillary analysis of the FILTER-HF trial, focused on the exercise outcomes. In a randomized, double-blind, 3-way crossover design, 26 HF patients and 15 control volunteers were exposed to clean air, unfiltered dilute diesel engine exhaust (DE), or filtered DE for 6min during a submaximal cardiopulmonary testing in a controlled-exposure facility. Prospectively collected data included six-minute walking test [6mwt], VO2, VE/VCO2 Slope, O2Pulse, pulmonary ventilation [VE], tidal volume, VD/Vt, oxyhemoglobin saturation and CO2-rebreathing. Compared to clean air, DE adversely affected VO2 (11.0±3.9 vs. 8.4±2.8ml/kg/min; peffects of pollution on VO2 and O2Pulse. Given the worldwide prevalence of exposure to traffic-related air pollution, these findings are relevant for public health especially in this highly susceptible population. The filter intervention holds great promise that needs to be tested in future studies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. A New Submaximal Rowing Test to Predict 2,000-m Rowing Ergometer Performance.

    Science.gov (United States)

    Otter, Ruby T A; Brink, Michel S; Lamberts, Robert P; Lemmink, Koen A P M

    2015-09-01

    The purpose of this study was to assess predictive value of a new submaximal rowing test (SmRT) on 2,000-m ergometer rowing time-trial performance in competitive rowers. In addition, the reliability of the SmRT was investigated. Twenty-four competitive male rowers participated in this study. After determining individual HRmax, all rowers performed an SmRT followed by a 2,000-m rowing ergometer time trial. In addition, the SmRT was performed 4 times (2 days in between) to determine the reliability. The SmRT consists of two 6-minute stages of rowing at 70 and 80% HRmax, followed by a 3-minute stage at 90% HRmax. Power was captured during the 3 stages, and 60 seconds of heart rate recovery (HRR60s) was measured directly after the third stage. Results showed that predictive value of power during the SmRT on 2,000-m rowing time also increased with stages. CVTEE% is 2.4, 1.9, and 1.3%. Pearson correlations (95% confidence interval [95% CI]) were -0.73 (-0.88 to -0.45), -0.80 (-0.94 to -0.67), and -0.93 (-0.97 to -0.84). 2,000-m rowing time and HRR60s showed no relationship. Reliability of power during the SmRT improved with the increasing intensity of the stages. The coefficient of variation (CVTEM%) was 9.2, 5.6, and 0.4%. Intraclass correlation coefficients (ICC) and 95% CI were 0.91 (0.78-0.97), 0.92 (0.81-0.97), and 0.99 (0.97-1.00). The CVTEM% and ICC of HRR60s were 8.1% and 0.93 (0.82-0.98). In conclusion, the data of this study shows that the SmRT is a reliable test that it is able to accurately predict 2,000-m rowing time on an ergometer. The SmRT is a practical and valuable submaximal test for rowers, which can potentially assist with monitoring, fine-tuning and optimizing training prescription in rowers.

  19. Validity and reliability of a field technique for sweat Na+ and K+ analysis during exercise in a hot‐humid environment

    Science.gov (United States)

    Baker, Lindsay B.; Ungaro, Corey T.; Barnes, Kelly A.; Nuccio, Ryan P.; Reimel, Adam J.; Stofan, John R.

    2014-01-01

    Abstract This study compared a field versus reference laboratory technique for extracting (syringe vs. centrifuge) and analyzing sweat [Na+] and [K+] (compact Horiba B‐722 and B‐731, HORIBA vs. ion chromatography, HPLC) collected with regional absorbent patches during exercise in a hot‐humid environment. Sweat samples were collected from seven anatomical sites on 30 athletes during 1‐h cycling in a heat chamber (33°C, 67% rh). Ten minutes into exercise, skin was cleaned/dried and two sweat patches were applied per anatomical site. After removal, one patch per site was centrifuged and sweat was analyzed with HORIBA in the heat chamber (CENTRIFUGE HORIBA) versus HPLC (CENTRIFUGE HPLC). Sweat from the second patch per site was extracted using a 5‐mL syringe and analyzed with HORIBA in the heat chamber (SYRINGE HORIBA) versus HPLC (SYRINGE HPLC). CENTRIFUGE HORIBA, SYRINGE HPLC, and SYRINGE HORIBA were highly related to CENTRIFUGE HPLC ([Na+]: ICC = 0.96, 0.94, and 0.93, respectively; [K+]: ICC = 0.87, 0.92, and 0.84, respectively), while mean differences from CENTRIFUGE HPLC were small but usually significant ([Na+]: 4.7 ± 7.9 mEql/L, −2.5 ± 9.3 mEq/L, 4.0 ± 10.9 mEq/L (all P sweat [Na+] and [K+] obtained with SYRINGE HORIBA falls within ±15.4 mEq/L and ±0.68 mEq/L, respectively, of CENTRIFUGE HPLC 95% of the time. The field (SYRINGE HORIBA) method of extracting and analyzing sweat from regional absorbent patches may be useful in obtaining sweat [Na+] when rapid estimates in a hot‐humid field setting are needed. PMID:24793982

  20. DHEA, DHEA-S and cortisol responses to acute exercise in older adults in relation to exercise training status and sex.

    Science.gov (United States)

    Heaney, Jennifer L J; Carroll, Douglas; Phillips, Anna C

    2013-04-01

    The aim of the present study was to investigate resting measures of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEA-S) and cortisol, and the response and recovery of these hormones to acute exercise, in male and female older adults of different exercise training status. Participants were 49 community-dwelling older adults (23 females) aged between 60 and 77 years who were either sedentary (n=14), moderately active (n=14) or endurance trained (n=21). Participants undertook an acute bout of exercise in the form of an incremental submaximal treadmill test. The exercise lasted on average 23 min 49 s (SD=2 min 8 s) and participants reached 76.5% (SD=5.44) of the predicted maximal heart rate. Blood samples were collected prior to exercise, immediately, and 1 h post-exercise. DHEA levels significantly increased immediately post-exercise; however, DHEA-S levels only significantly increased in females. Cortisol significantly decreased immediately post-exercise and 1 h post-exercise compared to pre-exercise. There were no significant differences in resting hormone levels or hormonal responses to exercise between training status groups. The findings suggest that exercise can stimulate DHEA production in older adults and that hormonal responses to exercise differ between male and female older adults.

  1. Pulsed electromagnetic field and exercises in patients with shoulder impingement syndrome: a randomized, double-blind, placebo-controlled clinical trial.

    Science.gov (United States)

    Galace de Freitas, Diego; Marcondes, Freddy Beretta; Monteiro, Renan Lima; Rosa, Sabrina Gonçalves; Maria de Moraes Barros Fucs, Patrícia; Fukuda, Thiago Yukio

    2014-02-01

    To evaluate the effects of pulsed electromagnetic field (PEMF) and exercises in reducing pain and improving function and muscle strength in patients with shoulder impingement syndrome (SIS). Double-blind, randomized controlled trial with a 3-month posttreatment follow-up. Outpatient rehabilitation of a public hospital. Patients (N=56) between 40 and 60 years of age, with a diagnosis of SIS, were randomly assigned to receive active PEMF (n=26; mean age, 50.1y) or placebo PEMF (n=30; mean age, 50.8y). After 3 weeks of active or placebo PEMF, both groups performed the same program of exercises that focused on shoulder strengthening. A visual analog scale, the University of California/Los Angeles shoulder rating scale, the Constant-Murley shoulder score, and handheld dynamometry for muscle strength were used as outcome measures at baseline (pretreatment), at 3 weeks (after active or placebo PEMF), at 9 weeks (postexercise), and at 3 months posttreatment. Patients in the active PEMF group had a higher level of function and less pain at all follow-up time frames compared with baseline (Pshoulder dynamometry, the active PEMF group had increased strength for lateral rotation at 9 weeks (Pshoulder strength in the placebo PEMF group (P>.05), as well as no significant differences (P>.05) for all outcome measures. The combination of PEMF and shoulder exercises is effective in improving function and muscle strength and decreasing pain in patients with SIS. However, these results should be carefully interpreted because of the lack of differences between groups. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  2. Prevention: Exercise

    Medline Plus

    Full Text Available ... A SPECIALIST Prevention Strengthening Exercise Committee Exercise Committee Core Strengthening Many popular forms of exercise focus on ... acute pain, you should stop doing it. Transverse Core Strengthening This strengthens the muscles that cross from ...

  3. Prevention: Exercise

    Medline Plus

    Full Text Available ... Smoking Weight Patient Safety Exercise Strengthening Strengthen Your Core! Stretching/Flexibility Aerobic Exercise Cervical Exercise Strength Training for the Elderly Other Back Pack Safety Pregnancy ...

  4. Exercise Physiologists

    Science.gov (United States)

    ... SITE MAP | EN ESPAÑOL Occupational Outlook Handbook > Healthcare > Exercise Physiologists PRINTER-FRIENDLY EN ESPAÑOL Summary What They ... of workers and occupations. What They Do -> What Exercise Physiologists Do About this section Exercise physiologists analyze ...

  5. The intent to exercise influences the cerebral O(2)/carbohydrate uptake ratio in humans

    DEFF Research Database (Denmark)

    Dalsgaard, Mads K; Ide, Kojiro; Cai, Yan

    2002-01-01

    to 3.7 +/- 0.2 in the first minutes of the recovery (P exercise did not change the uptake ratio significantly. Yet, in a second experiment, when submaximal exercise required a maximal effort due to partial neuromuscular blockade, the ratio decreased and remained low (4.9 +/- 0.2......During and after maximal exercise there is a 15-30 % decrease in the metabolic uptake ratio (O(2)/[glucose + 1/2 lactate]) and a net lactate uptake by the human brain. This study evaluated if this cerebral metabolic uptake ratio is influenced by the intent to exercise, and whether a change could......) in the early recovery (n = 10; P 2) when the brain is activated by exhaustive exercise, and that such metabolic changes are influenced by the will to exercise. We speculate that the uptake ratio...

  6. Physiological and nutritional aspects of post-exercise recovery: specific recommendations for female athletes.

    Science.gov (United States)

    Hausswirth, Christophe; Le Meur, Yann

    2011-10-01

    Gender-based differences in the physiological response to exercise have been studied extensively for the last four decades, and yet the study of post-exercise, gender-specific recovery has only been developing in more recent years. This review of the literature aims to present the current state of knowledge in this field, focusing on some of the most pertinent aspects of physiological recovery in female athletes and how metabolic, thermoregulatory, or inflammation and repair processes may differ from those observed in male athletes. Scientific investigations on the effect of gender on substrate utilization during exercise have yielded conflicting results. Factors contributing to the lack of agreement between studies include differences in subject dietary or training status, exercise intensity or duration, as well as the variations in ovarian hormone concentrations between different menstrual cycle phases in female subjects, as all are known to affect substrate metabolism during sub-maximal exercise. If greater fatty acid mobilization occurs in females during prolonged exercise compared with males, the inverse is observed during the recovery phase. This could explain why, despite mobilizing lipids to a greater extent than males during exercise, females lose less fat mass than their male counterparts over the course of a physical training programme. Where nutritional strategies are concerned, no difference appears between males and females in their capacity to replenish glycogen stores; optimal timing for carbohydrate intake does not differ between genders, and athletes must consume carbohydrates as soon as possible after exercise in order to maximize glycogen store repletion. While lipid intake should be limited in the immediate post-exercise period in order to favour carbohydrate and protein intake, in the scope of the athlete's general diet, lipid intake should be maintained at an adequate level (30%). This is particularly important for females specializing in

  7. Vascular Dynamics and Peripheral Oxygen Uptake in Obese Individuals during Progressive Physical Exercise.

    Science.gov (United States)

    Brunani, Amelia; Lanzi, Stefano; Codecasa, Franco; Cornacchia, Mauro; Maestrini, Sabrina; Soranna, Davide; Zambon, Antonella; Cattaldo, Stefania; Fanari, Paolo; Malatesta, Davide; Salvadori, Alberto

    2017-01-01

    Obese men show higher O2 consumption than lean men during physical exercise, with a trend toward higher peripheral O2 extraction; this is probably due to their larger muscle mass. The aim of this study was to examine this phenomenon by measuring 2 vasoactive substances, endothelin-1 (ET-1) and nitric oxide (NO), during a progressive submaximal exercise. Seventeen obese (body mass index [BMI] 38.6) and 15 lean (BMI 22.5) men performed a maximal progressive cycle ergometer exercise to determine peak power output (PPO) and peak O2 consumption (V∙O2peak); thereafter, they performed a submaximal cycle ergometer incremental test (every 6 min) at the same percentage of V∙O2peak until they reached 57.5% PPO. Blood samples were collected at rest and at the end of every step to measure ET-1 and NO concentrations. At rest, the ET-1 and NO concentrations in obese men and lean controls were the same. However, during exercise, the ET-1 concentration at each step was significantly lower (p < 0.05) in the obese group. There was no significant difference in NO concentration between the 2 groups, although the increase at the beginning of the exercise session was faster in obese individuals. During submaximal exercise, end-tidal O2 pressure (PETO2) was lower in the obese group, with a significant difference in the PETO2/fat-free mass ratio at each step. ET-1 and NO levels during physical exercise are different in obese versus lean men. This may support the notion that increased O2 consumption in obesity is due to different behaviors of the cardiorespiratory and circulatory systems. © 2017 S. Karger AG, Basel.

  8. "Tailored" submaximal step test for VO2max prediction in healthy older adults.

    Science.gov (United States)

    Pogliaghi, Silvia; Bellotti, Cecilia; Paterson, Donald H

    2014-04-01

    The authors developed and validated a "tailored" version of the Astrand-Rhyming step test (tA-R) and a new equation for VO2max prediction in older adults (OA). Sixty subjects (age 68 ± 4 yr, 30 male, 30 female) performed their tA-R step test (5-min, 30-cm step, tailored stepping rate) and an incremental cycling test to exhaustion. VO2max was (a) predicted using the standard A-R equation (predicted VO2max), (b) predicted based on the authors' new multiple linear equation (equation VO2max), and (c) directly measured by incremental cycling test (direct VO2max). Agreement among values of VO2max was evaluated by Bland-Altman analysis. The predicted VO2max was not significantly different from the direct VO2max, yet with relatively large imprecision. The equation VO2max allowed more precise as well as accurate predictions of VO2max compared with standard A-R prediction. The "tailored" version of the Astrand-Rhyming step test and the new prediction equation appear suitable for a rapid (5-min), safe (submaximal), accurate, and precise VO2max prediction in healthy OA.

  9. Predictability of maximum voluntary isometric knee extension force from submaximal contractions in older adults.

    Science.gov (United States)

    Stackhouse, Scott K; Stevens, Jennifer E; Johnson, Christopher D; Snyder-Mackler, Lynn; Binder-Macleod, Stuart A

    2003-01-01

    The purposes of this study were to develop and test a model describing the relationship between the central activation ratio (CAR; a measure of voluntary muscle activation) and percent maximum voluntary contraction (%MVC) force for old adults and to provide a method for more accurate determination of voluntary muscle activation failure. Twenty-one adults (ages 64-81) performed isometric testing of the quadriceps at 25%, 50%, 75%, and 100% MVC. During each contraction, a 100-HZ, 120-ms train of electrical pulses was delivered to the quadriceps muscle to quantify voluntary muscle activation. Similar to a young, healthy population (ages 20-35), a curvilinear relationship existed between the CAR and %MVC force for older adults. Predictions of subjects' MVCs using the linear model of CAR-%MVC force relationship generally demonstrated poor agreement with actual MVCs. Predictions of MVC from submaximal contractions (25%, 50%, and 75%) using a previously identified curvilinear young adult CAR-%MVC relationship were good [ICC (2,1): 0.81, 0.96, and 0.82, respectively]. Similar agreement was obtained from the curvilinear older adult CAR-%MVC relationship. These data suggest that the CAR-%MVC relationship is similar in young and older adult subjects and that curvilinear models of this relationship can predict MVC forces in older adults more accurately. Reexamination of the relationship between the CAR and %MVC force may allow a more accurate determination of how failure of voluntary muscle activation contributes to weakness in old adults.

  10. 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.

  11. Prevention: Exercise

    Medline Plus

    Full Text Available ... strengthening programs. Simple exercises can be done at home as well. Some specific core strengthening exercises are described below. ... © 2017 North American Spine Society | ...

  12. Clinical physiology of exercise in pregnancy: a literature review.

    Science.gov (United States)

    Wolfe, Larry A; Weissgerber, Tracey L

    2003-06-01

    To review the existing literature on the physiology of exercise in pregnancy as a basis for clinical practice guidelines for prenatal exercise prescription. MEDLINE search for English language abstracts and articles published between 1966 and 2003 related to physiological adaptations to pregnancy, effects of pregnancy on responses to acute exercise and aerobic conditioning, effects of acute maternal exercise on indexes of fetal well-being, impact of physical conditioning on birth weight and other pregnancy outcomes, and use of exercise to prevent or treat gestational diabetes mellitus and preeclampsia. Maximal aerobic power (VO(2)max, L/min) is well-preserved in pregnant women who remain physically active, but anaerobic working capacity may be reduced in late gestation. The increase in resting heart rate, reduction in maximal heart rate, and resulting smaller heart rate reserve render heart rate a less precise way of estimating exercise intensity. As rating of perceived exertion (RPE) is not altered by pregnancy, the use of revised pulse rate target zones along with Borg's RPE scale is recommended to prescribe exercise intensity during pregnancy. Responses to prolonged submaximal exercise (>30 min) in late gestation include a moderate reduction in maternal blood glucose concentration, which may transiently reduce fetal glucose availability. The normal response to sustained submaximal exercise is an increase in fetal heart rate (FHR) baseline. Transient reductions in FHR reactivity, fetal breathing movements, and FHR variability may also occur in association with more strenuous exercise. Controlled prospective studies have demonstrated that moderate prenatal exercise during the second and third trimesters is useful to improve aerobic fitness and maternal-fetal physiological reserve without affecting fetal growth. The Physical Activity Readiness Medical Examination for Pregnancy is recommended for use by physicians and midwives to provide medical clearance for

  13. Psychosocial Influences on Exercise-Induced Hypoalgesia.

    Science.gov (United States)

    Brellenthin, Angelique G; Crombie, Kevin M; Cook, Dane B; Sehgal, Nalini; Koltyn, Kelli F

    2017-03-01

    The purpose of this study was to examine psychosocial influences on exercise-induced hypoalgesia (EIH). Randomized controlled trial. Clinical research unit in a hospital. Fifty-eight healthy men and women (mean age = 21 ± 3 years) participated in this study. Participants were first asked to complete a series of baseline demographic and psychological questionnaires including the Pain Catastrophizing Scale, the Fear of Pain Questionnaire, and the Family Environment Scale. Following this, they were familiarized with both temporal summation of heat pain and pressure pain testing protocols. During their next session, participants completed the Profile of Mood States, rated the intensity of heat pulses, and indicated their pressure pain thresholds and ratings before and after three minutes of submaximal, isometric exercise. Situational catastrophizing was assessed at the end of the experimental session. Results indicated that experimental pain sensitivity was significantly reduced after exercise ( P   0.05). Positive family environments predicted attenuated pain sensitivity and greater EIH, whereas negative and chronic pain-present family environments predicted worse pain and EIH outcomes. Situational catastrophizing and negative mood state also predicted worse pain and EIH outcomes and were additionally associated with increased ratings of perceived exertion and muscle pain during exercise. This study provides preliminary evidence that psychosocial variables, such as the family environment and mood states, can affect both pain sensitivity and the ability to modulate pain through exercise-induced hypoalgesia.

  14. Physiologic considerations for exercise performance in women.

    Science.gov (United States)

    Charkoudian, Nisha; Joyner, Michael J

    2004-06-01

    Women exhibit several anatomic and physiologic characteristics that distinguish their responses to exercise from those of men. Women are smaller than men, have less muscle mass, and more fat mass for a given body size. Blood volume, stroke volume, and cardiac output are all lower in women than in men. These and other factors contribute to lower maximal aerobic power (even for similar training status) in women. The reproductive hormones, estrogen and progesterone, can influence ventilation, substrate metabolism, and thermoregulation during exercise. Women have a greater tendency for EIAH, which can limit VO2max as well as submaximal exercise performance at higher intensities. Women tend to use a greater percentage of fats during exercise, but also rely on CHOs. Thermoregulatory control is altered significantly over the course of the menstrual cycle by fluctuations in circulating levels of progesterone and estrogen. It is important for women to include regular exercise in their daily routines, particularly because regular physical activity has been implicated in the prevention of osteoporosis, breast cancer, heart disease, and depression.

  15. Aquatic exercise training for fibromyalgia.

    Science.gov (United States)

    Bidonde, Julia; Busch, Angela J; Webber, Sandra C; Schachter, Candice L; Danyliw, Adrienne; Overend, Tom J; Richards, Rachel S; Rader, Tamara

    2014-10-28

    Exercise training is commonly recommended for individuals with fibromyalgia. This review examined the effects of supervised group aquatic training programs (led by an instructor). We defined aquatic training as exercising in a pool while standing at waist, chest, or shoulder depth. This review is part of the update of the 'Exercise for treating fibromyalgia syndrome' review first published in 2002, and previously updated in 2007. The objective of this systematic review was to evaluate the benefits and harms of aquatic exercise training in adults with fibromyalgia. We searched The Cochrane Library 2013, Issue 2 (Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Health Technology Assessment Database, NHS Economic Evaluation Database), MEDLINE, EMBASE, CINAHL, PEDro, Dissertation Abstracts, WHO international Clinical Trials Registry Platform, and AMED, as well as other sources (i.e., reference lists from key journals, identified articles, meta-analyses, and reviews of all types of treatment for fibromyalgia) from inception to October 2013. Using Cochrane methods, we screened citations, abstracts, and full-text articles. Subsequently, we identified aquatic exercise training studies. Selection criteria were: a) full-text publication of a randomized controlled trial (RCT) in adults diagnosed with fibromyalgia based on published criteria, and b) between-group data for an aquatic intervention and a control or other intervention. We excluded studies if exercise in water was less than 50% of the full intervention. We independently assessed risk of bias and extracted data (24 outcomes), of which we designated seven as major outcomes: multidimensional function, self reported physical function, pain, stiffness, muscle strength, submaximal cardiorespiratory function, withdrawal rates and adverse effects. We resolved discordance through discussion. We evaluated interventions using mean differences

  16. Effects of parental smoking on exercise systolic blood pressure in adolescents.

    Science.gov (United States)

    Hacke, Claudia; Weisser, Burkhard

    2015-05-11

    In adults, exercise blood pressure seems to be more closely related to cardiovascular risk than resting blood pressure; however, few data are available on the effects of familial risk factors, including smoking habits, on exercise blood pressure in adolescents. Blood pressure at rest and during exercise, parental smoking, and other familial risk factors were investigated in 532 adolescents aged 12 to 17 years (14.6±1.5 years) in the Kiel EX.PRESS. (EXercise PRESSure) Study. Exercise blood pressure was determined at 1.5 W/kg body weight using a standardized submaximal cycle ergometer test. Mean resting blood pressure was 113.1±12.8/57.2±7.1 mm Hg, and exercise blood pressure was 149.9±19.8/54.2±8.6 mm Hg. Parental smoking increased exercise systolic blood pressure (+4.0 mm Hg, 3.1 to 4.9; P=0.03) but not resting blood pressure of the subjects (adjusted for age, sex, height, body mass index percentile, fitness). Parental overweight and familial hypertension were related to both higher resting and exercise systolic blood pressure values, whereas associations with an inactive lifestyle and a low educational level of the parents were found only with adolescents' blood pressure during exercise. The cumulative effect of familial risk factors on exercise systolic blood pressure was more pronounced than on blood pressure at rest. Parental smoking might be a novel risk factor for higher blood pressure, especially during exercise. In addition, systolic blood pressure during a submaximal exercise test was more closely associated with familial risk factors than was resting blood pressure, even in adolescents. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  17. Assessment Of Physiological Cardio respiratory Parameters During Sub maximal Exercise On Acute Exposure To Normobaric Hypoxia In Healthy Young Males

    Directory of Open Access Journals (Sweden)

    Bipin K Shrestha

    2016-06-01

    Full Text Available To estimate changes in SBP, DBP, HR, RR and Lactate Level at Near Sea Level (NSL and at Simulated altitude (3000meters at rest and during sub-maximal exercise.Mean Resting values at NSL vs. Hypoxic Chamber were: SBP (1276vs1325mmHg, DBP (703vs786mmHg, HR (725vs806bpm, RR (254vs293/min and LL (2.10.35vs2.50.42mmol/l. Similarly, mean values at the end of exercise were: SBP (1529vs16913mmHg, DBP (836vs926mmHg, HR (13412vs1557bpm, RR (356vs516/min and LL (7.110.89vs8.011.03mmol/l.  A significant difference exists in mean resting values of SBP, DBP, HR and RR at NSL and on acute exposure to Normobaric Hypoxia. Sub-maximal exercise in hypoxic conditions appears to depend more on anaerobic metabolism and results in greater sympathetic activity. Keywords: Cardiorespiratory parameters, Normobaric hypoxia, Sub-maximal exercise, Near Sea Level

  18. State Labour Inspectorate – specialized authority exercising supervising and control tasks in the field of labour security and health

    Directory of Open Access Journals (Sweden)

    Nicolae ROMANDAŞ

    2016-06-01

    Full Text Available In present, State Labour Inspectorate is the main supervisory body in health and safety at the work, and has all the rights to exercise an efficient control in order to target the compliance of employers of legal regulations which aim mentioned sphere. Therefore, the mechanism which involves changes in work culture, the most important from of them which refers to security and healthy of work place, take place in our society for harmonization and labor market adjustment. It is obviously that more units start to realize that human resources are most important capital of an organization and is the decisive factor in the production process. That’s why employers should be conscious about the fact that security of an employee it’s not an expanse, but a necessary investment to avoid some costs, direct or indirect caused by work stoppages in the case of a serious and imminent danger or in cases the most unfortunate, the consequences of accidents at work and occupational diseases.

  19. Mental fatigue does not affect maximal anaerobic exercise performance.

    Science.gov (United States)

    Martin, Kristy; Thompson, Kevin G; Keegan, Richard; Ball, Nick; Rattray, Ben

    2015-04-01

    Mental fatigue can negatively impact on submaximal endurance exercise and has been attributed to changes in perceived exertion rather than changes in physiological variables. The impact of mental fatigue on maximal anaerobic performance is, however, unclear. Therefore, the aim of the present study was to induce a state of mental fatigue to examine the effects on performance, physiological and perceptual variables from subsequent tests of power, strength and anaerobic capacity. Twelve participants took part in the single-blind, randomised, crossover design study. Mental fatigue was induced by 90 min of the computer-based Continuous Performance Task AX version. Control treatment consisted of 90 min of watching emotionally neutral documentaries. Participants consequently completed countermovement jump, isometric leg extension and a 3-min all-out cycling tests. Results of repeated measures analysis of variance and paired t tests revealed no difference in any performance or physiological variable. Rating of perceived exertion tended to be greater when mentally fatigued (mental fatigue = 19 ± 1 vs control = 18 ± 1, p = 0.096, [Formula: see text] = .232) and intrinsic motivation reduced (mental fatigue = 11 ± 4 vs control = 13 ± 6, p = 0.063, d = 0.597) in the mental fatigue condition. Near identical responses in performance and physiological parameters between mental fatigue and control conditions suggest that peripheral mechanisms primarily regulate maximal anaerobic exercise. Whereas mental fatigue can negatively impact submaximal endurance exercise, it appears that explosive power, voluntary maximal strength and anaerobic work capacity are unaffected.

  20. Relationships between field performance tests in high-level soccer players.

    Science.gov (United States)

    Ingebrigtsen, Jørgen; Brochmann, Marit; Castagna, Carlo; Bradley, Paul S; Ade, Jack; Krustrup, Peter; Holtermann, Andreas

    2014-04-01

    submaximal HRs after 2 and 4 minutes were independently associated with Yo-Yo IR1 and IR2 performances (p ≤ 0.01). In conclusion, Yo-Yo IR1 and 2 test performances, as well as sprint and RSA performances, correlated very largely, and it may therefore be considered using only one of the Yo-Yo tests and a RSA test, in a general soccer-specific field test protocol. The submaximal HR measures during Yo-Yo tests are reproducible and may be used for frequent, time-efficient, and nonexhaustive testing of intermittent exercise capacity of high-level soccer players.

  1. Exercise Prescription.

    Science.gov (United States)

    Ribisl, Paul M.

    If exercise programs are to become effective in producing the desired results, then the correct exercise prescription must be applied. Four variables should be controlled in the prescription of exercise: (a) type of activity, (b) intensity, (c) duration, and (d) frequency. The long-term prescription of exercise involves the use of a (a) starter…

  2. Cardiovascular adaptation in people with multiple sclerosis following a twelve week exercise programme suggest deconditioning rather than autonomic dysfunction caused by the disease. Results from a randomized controlled trial.

    Science.gov (United States)

    Feltham, M G; Collett, J; Izadi, H; Wade, D T; Morris, M G; Meaney, A J; Howells, K; Sackley, C; Dawes, H

    2013-12-01

    Guidelines for optimal exercise doses in people with multiple sclerosis (MS) have to be established. We need to ascertain the basic physiological and perceptual response and adaptation to different exercise doses in this clinical population. The aim of this paper was to explore the response during maximal and sub-maximal exercise in people with MS prior to and following two different twelve week exercise programmes. Sub-analysis of per protocol exercise data of a two group, single blinded, randomised control trial. Multicentre (community leisure and rehabilitation centres). Participants with MS assigned to a continuous (N.=12; mean±SE age=52.3±2.08; Barthel index median & range=19&13-20) or interval (N.=9; mean±SE age=49.3±3.5; Barthel index median & range=19&18-20) exercise programme. Cardiovascular, respiratory and perceptual exercise response and adaption was measured at maximal and sub-maximal levels of physical exercise prior to and following a twelve week exercise programme, delivered at different intensities. Irrespective of the type of exercise programme followed, there was a significant increase in peak power (z=-1.98; P=0.05) and normalised oxygen uptake during unloaded cycling (z =-2.00; P=0.05). At discharge from the exercise programmes, the cardiovascular response to sub-maximal exercise had significantly changed (t(360) =-4.62; pphysical exercise following a twelve week programme is analogous to non-diseased adults. Cardiovascular adaptation in people with MS following a twelve week exercise programme suggests deconditioning rather than autonomic dysfunction caused by the disease.

  3. Effects of antiorthostatic bedrest on the cardiorespiratory responses to exercise

    Science.gov (United States)

    Convertino, V. A.; Bisson, R.; Bates, R.; Goldwater, D.; Sandler, H.

    1981-01-01

    The cardiorespiratory changes in exercise performance induced by horizontal and antiorthostatic bed rest are compared in order to determine the physiological changes occurring in the antiorthostatic position and their degree of similarity to those observed in weightlessness. Systolic and diastolic pressures, heart rates, maximum oxygen uptake, ventilation volume during and following 5 min of submaximal exercise in the supine position and body weight and composition were determined in subjects before and following 7 days of bed rest in the horizontal or 6-deg head-down positions. Bed rest is found to result in a general decrease in exercise tolerance as indicated by cardiorespiratory parameters in both groups, with the 6-deg head-down treatment causing greater cardiovascular deconditioning. When compared with space flight data, the antiorthostatic position is shown to simulate the effects of weightlessness more effectively than horizontal bed rest

  4. Field versus race pace conditions to provoke exercise-induced bronchoconstriction in elite swimmers: Influence of training background

    Directory of Open Access Journals (Sweden)

    Michael D. Kennedy

    2017-06-01

    Conclusion: All conditions have poor sensitivity to diagnose EIB and total accumulated ventilation (distance swum did not influence AHR. These results also indicate that elite swimmers, despite many risk factors, are not limited by respiratory function in race conditions. It is proposed that the swim field test not be used for AHR assessment in swimmers due to too high relative humidity.

  5. Affect-regulated exercise intensity: does training at an intensity that feels 'good' improve physical health?

    Science.gov (United States)

    Parfitt, Gaynor; Alrumh, Amnah; Rowlands, Alex V

    2012-11-01

    Affect-regulated exercise to feel 'good' can be used to control exercise intensity amongst both active and sedentary individuals and should support exercise adherence. It is not known, however, whether affect-regulated exercise training can lead to physical health gains. The aim of this study was to examine if affect-regulated exercise to feel 'good' leads to improved fitness over the course of an 8-week training programme. A repeated measures design (pretest-posttest) with independent groups (training and control). 20 sedentary females completed a submaximal graded exercise test and were then allocated to either a training group or control group. The training group completed two supervised sessions and one unsupervised session per week for 8 weeks. Exercise intensity was affect-regulated to feel 'good'. Following the 8 weeks of training, both groups completed a second submaximal graded exercise test. Repeated measures analyses of variance indicated a significant increase in the time to reach ventilatory threshold in the training group (318 ± 23.7s) compared to control (248 ± 16.9s). Overall compliance to training was high (>92%). Participants in the training group exercised at intensities that would be classified as being in the lower range of the recommended guidelines (≈ 50% V˙O(2) max) for cardiovascular health. Affect-regulated exercise to feel 'good' can be used in a training programme to regulate exercise intensity. This approach led to a 19% increase in time to reach ventilatory threshold, which is indicative of improved fitness. Copyright © 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  6. Cortical and spinal mechanisms of task failure of sustained submaximal fatiguing contractions.

    Directory of Open Access Journals (Sweden)

    Petra S Williams

    Full Text Available In this and the subsequent companion paper, results are presented that collectively seek to delineate the contribution that supraspinal circuits have in determining the time to task failure (TTF of sustained submaximal contractions. The purpose of this study was to compare adjustments in supraspinal and spinal excitability taken concurrently throughout the performance of two different fatigue tasks with identical mechanical demands but different TTF (i.e., force-matching and position-matching tasks. On separate visits, ten healthy volunteers performed the force-matching or position-matching task at 15% of maximum strength with the elbow flexors to task failure. Single-pulse transcranial magnetic stimulation (TMS, paired-pulse TMS, paired cortico-cervicomedullary stimulation, and brachial plexus electrical stimulation were delivered in a 6-stimuli sequence at baseline and every 2-3 minutes throughout fatigue-task performance. Contrary to expectations, the force-matching task TTF was 42% shorter (17.5 ± 7.9 min than the position-matching task (26.9 ± 15.11 min; p0.05. Therefore, failure occurred after a similar mean decline in motorneuron excitability developed (p0.10 and an index of upstream excitation of the motor cortex remained constant (p>0.40. Together, these results suggest that as fatigue develops prior to task failure, the increase in corticospinal excitability observed in relationship to the decrease in spinal excitability results from a combination of decreasing intracortical inhibition with constant levels of intracortical facilitation and upstream excitability that together eventually fail to provide the input to the motor cortex necessary for descending drive to overcome the spinal cord resistance, thereby contributing to task failure.

  7. Cortical and Spinal Mechanisms of Task Failure of Sustained Submaximal Fatiguing Contractions

    Science.gov (United States)

    Williams, Petra S.; Hoffman, Richard L.; Clark, Brian C.

    2014-01-01

    In this and the subsequent companion paper, results are presented that collectively seek to delineate the contribution that supraspinal circuits have in determining the time to task failure (TTF) of sustained submaximal contractions. The purpose of this study was to compare adjustments in supraspinal and spinal excitability taken concurrently throughout the performance of two different fatigue tasks with identical mechanical demands but different TTF (i.e., force-matching and position-matching tasks). On separate visits, ten healthy volunteers performed the force-matching or position-matching task at 15% of maximum strength with the elbow flexors to task failure. Single-pulse transcranial magnetic stimulation (TMS), paired-pulse TMS, paired cortico-cervicomedullary stimulation, and brachial plexus electrical stimulation were delivered in a 6-stimuli sequence at baseline and every 2–3 minutes throughout fatigue-task performance. Contrary to expectations, the force-matching task TTF was 42% shorter (17.5±7.9 min) than the position-matching task (26.9±15.11 min; pmuscle fatigue (p = 0.59). There were no task-specific differences for the total amount or rate of change in the neurophysiologic outcome variables over time (p>0.05). Therefore, failure occurred after a similar mean decline in motorneuron excitability developed (p0.10) and an index of upstream excitation of the motor cortex remained constant (p>0.40). Together, these results suggest that as fatigue develops prior to task failure, the increase in corticospinal excitability observed in relationship to the decrease in spinal excitability results from a combination of decreasing intracortical inhibition with constant levels of intracortical facilitation and upstream excitability that together eventually fail to provide the input to the motor cortex necessary for descending drive to overcome the spinal cord resistance, thereby contributing to task failure. PMID:24667484

  8. Inspiratory muscle training improves exercise capacity with thoracic load carriage.

    Science.gov (United States)

    Shei, Ren-Jay; Chapman, Robert F; Gruber, Allison H; Mickleborough, Timothy D

    2018-02-01

    Thoracic load carriage (LC) exercise impairs exercise performance compared to unloaded exercise, partially due to impaired respiratory mechanics. We investigated the effects of LC on exercise and diaphragmatic fatigue in a constant-load exercise task; and whether inspiratory muscle training (IMT) improved exercise capacity and diaphragmatic fatigue with LC. Twelve recreationally active males completed three separate running trials to exhaustion (T lim ) at a fixed speed eliciting 70% of their V˙O 2max . The first two trials were completed either unloaded (UL) or while carrying a 10 kg backpack (LC). Subjects then completed 6 weeks of either true IMT or placebo-IMT. Posttraining, subjects completed an additional LC trial identical to the pretraining LC trial. Exercise metabolic and ventilatory measures were recorded. Diaphragm fatigue was assessed as the difference between preexercise and postexercise twitch diaphragmatic pressure (P di, tw ), assessed by bilateral stimulation of the phrenic nerve with esophageal balloon-tipped catheters measuring intrathoracic pressures. T lim was significantly shorter (P  0.05). Minute ventilation and breathing mechanics were unchanged post-IMT (P > 0.05). Six weeks of flow-resistive IMT improved exercise capacity, but did not mitigate diaphragmatic fatigue following submaximal, constant-load running to volitional exhaustion with LC. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  9. 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

    2017-10-12

    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.

  10. Health benefits of exercise in an aging society.

    Science.gov (United States)

    Larson, E B; Bruce, R A

    1987-02-01

    The effects of regular aerobic exercise are important to an aging society increasingly preoccupied with exercise. Traditionally, most attention has been directed to the relationship between a physically active life-style and cardiovascular mortality. In an aging society, however, active life expectancy and maintenance of independence may be as important as effects of regular exercise on longevity. Regular exercise results in increased maximum aerobic capacity due to peripheral changes in muscle (increased capacity for aerobic metabolism and improved substrate and oxygen extraction with a widened arteriovenous oxygen difference) and also due to cardiovascular changes with increased stroke volume and cardiac output in normal persons. "Therapeutic benefits" of conditioning probably occur at submaximal work loads common to everyday activity, when cardiac work and myocardial oxygen consumption are less for any given work load, muscles are more efficient, and relative oxygen requirements are less. Aging is associated with a linear decline in maximum aerobic capacity. The rate of decline is twofold greater when comparing sedentary with physically active middle-aged men. Thus, regular exercise could conceivably lower functional aerobic age by slowing this functional decline. Exercise, particularly excessive exercise, is also associated with serious hazards, including sudden death, nonfatal myocardial infarction, excessive fatigue, hyperthermia, and significant musculoskeletal problems. Accounts of the health effects of exercise should consider a wide range of risks and benefits, especially those related to improving function, minimizing disability, and prolonging independent living.

  11. Cardiorespiratory response to exercise on a large therapeutic roll.

    Science.gov (United States)

    Gappmaier, Eduard; Tavazoie, Sima F; Jacketta, Michael G

    2013-09-01

    Large therapeutic rolls (LTR) and balls are popular rehabilitation tools and have also been advertised as cardiovascular training devices. The aim of this study was to determine if individuals of varying fitness levels would reach aerobic training levels by evidence-based standards as described in American College of Sports Medicine (ACSM) publications. Fourteen volunteers performed a maximal exercise test and on subsequent days, two submaximal exercise tests on the LTR (LTR-A and -B). LTR-A consisted of four 5-minute stages of exercise at progressive intensity levels. LTR-B included 20 minutes of continuous exercise. Oxygen consumption (VO2) and heart rate (HR) during exercise on the LTR were compared with ACSM recommended standards. The average (range) peak intensity achieved during LTR-A was 66.8% (51.7-82.7%) of maximal VO2 reserve (VO2R) and 82.9% (70.7%-91.2%) of maximal heart rate (HRmax). During LTR-B, HR and VO2 of all participants was maintained at moderate exercise intensity and averaged 56% of VO2R and 78% of HRmax during the 20 minute exercise period. These findings suggest that individuals with a wide range of aerobic fitness are able to reach and maintain aerobic training levels with appropriate exercise on a large therapeutic roll or ball.

  12. Effect of acute aerobic exercise and histamine receptor blockade on arterial stiffness in African Americans and Caucasians.

    Science.gov (United States)

    Yan, Huimin; Ranadive, Sushant M; Lane-Cordova, Abbi D; Kappus, Rebecca M; Behun, Michael A; Cook, Marc D; Woods, Jeffrey A; Wilund, Kenneth R; Baynard, Tracy; Halliwill, John R; Fernhall, Bo

    2017-02-01

    African Americans (AA) exhibit exaggerated central blood pressure (BP) and arterial stiffness measured by pulse wave velocity (PWV) in response to an acute bout of maximal exercise compared with Caucasians (CA). However, whether potential racial differences exist in central BP, elastic, or muscular arterial distensibility after submaximal aerobic exercise remains unknown. Histamine receptor activation mediates sustained postexercise hyperemia in CA but the effect on arterial stiffness is unknown. This study sought to determine the effects of an acute bout of aerobic exercise on central BP and arterial stiffness and the role of histamine receptors, in AA and CA. Forty-nine (22 AA, 27 CA) young and healthy subjects completed the study. Subjects were randomly assigned to take either histamine receptor antagonist or control placebo. Central blood BP and arterial stiffness measurements were obtained at baseline, and at 30, 60, and 90 min after 45 min of moderate treadmill exercise. AA exhibited greater central diastolic BP, elevated brachial PWV, and local carotid arterial stiffness after an acute bout of submaximal exercise compared with CA, which may contribute to their higher risk of cardiovascular disease. Unexpectedly, histamine receptor blockade did not affect central BP or PWV in AA or CA after exercise, but it may play a role in mediating local carotid arterial stiffness. Furthermore, histamine may mediate postexercise carotid arterial dilation in CA but not in AA. These observations provide evidence that young and healthy AA exhibit an exaggerated hemodynamic response to exercise and attenuated vasodilator response compared with CA.NEW & NOTEWORTHY African Americans are at greater risk for developing cardiovascular disease than Caucasians. We are the first to show that young and healthy African Americans exhibit greater central blood pressure, elevated brachial stiffness, and local carotid arterial stiffness following an acute bout of submaximal exercise

  13. DIURNAL VARIATION OF HAEMOSTATIC RESPONSE TO EXERCISE IN YOUNG SEDENTARY MALES

    OpenAIRE

    Marefat Siahkouhian; Davar Khodadadi; Lotfali Bolboli

    2013-01-01

    The aim of this study was to evaluate diurnal variations in the haemostatic response to submaximal exercise performed by young, sedentary men. Fifteen healthy young sedentary males aged 25.6 ± 1.34 (mean ± SD) years performed two exercise sessions, morning and evening, at 70% of maximal oxygen consumption ( V . O2max) on a cycle ergometer for 30 min. Platelet count (PC), activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen, tissue plasminogen activator (tPA) and pla...

  14. Exercise and functional foods

    Directory of Open Access Journals (Sweden)

    Naito Yuji

    2006-06-01

    Full Text Available Abstract Appropriate nutrition is an essential prerequisite for effective improvement of athletic performance, conditioning, recovery from fatigue after exercise, and avoidance of injury. Nutritional supplements containing carbohydrates, proteins, vitamins, and minerals have been widely used in various sporting fields to provide a boost to the recommended daily allowance. In addition, several natural food components have been found to show physiological effects, and some of them are considered to be useful for promoting exercise performance or for prevention of injury. However, these foods should only be used when there is clear scientific evidence and with understanding of the physiological changes caused by exercise. This article describes various "functional foods" that have been reported to be effective for improving exercise performance or health promotion, along with the relevant physiological changes that occur during exercise.

  15. Effects of training status on PDH regulation in human skeletal muscle during exercise

    DEFF Research Database (Denmark)

    Gudiksen, Anders; Bertholdt, Lærke; Stankiewicz, Tomasz

    2017-01-01

    of this study was to investigate the impact of training state on post-translational regulation of PDHa activity during submaximal and exhaustive exercise. Eight untrained and nine endurance exercise-trained healthy male subjects performed incremental exercise on a cycle ergometer: 40 min at 50% incremental peak...... power output (IPPO), 10 min at 65% (IPPO), followed by 80% (IPPO) until exhaustion. Trained subjects had higher (P muscle PDH......Pyruvate dehydrogenase (PDH) is the gateway enzyme for carbohydrate-derived pyruvate feeding into the TCA cycle. PDH may play a central role in regulating substrate shifts during exercise, but the influence of training state on PDH regulation during exercise is not fully elucidated. The purpose...

  16. Sympathetic influence on cerebral blood flow and metabolism during exercise in humans

    DEFF Research Database (Denmark)

    Seifert, Thomas; Secher, Niels H

    2011-01-01

    This review focuses on the possibility that autonomic activity influences cerebral blood flow (CBF) and metabolism during exercise in humans. Apart from cerebral autoregulation, the arterial carbon dioxide tension, and neuronal activation, it may be that the autonomic nervous system influences CBF......-oxidative carbohydrate uptake during exercise. Adrenaline appears to accelerate cerebral glycolysis through a beta2-adrenergic receptor mechanism since noradrenaline is without such an effect. In addition, the exercise-induced cerebral non-oxidative carbohydrate uptake is blocked by combined beta 1/2-adrenergic blockade......, but not by beta1-adrenergic blockade. Furthermore, endurance training appears to lower the cerebral non-oxidative carbohydrate uptake and preserve cerebral oxygenation during submaximal exercise. This is possibly related to an attenuated catecholamine response. Finally, exercise promotes brain health as evidenced...

  17. Hypoxia and exercise provoke both lactate release and lactate oxidation by the human brain

    DEFF Research Database (Denmark)

    Overgaard, Morten; Rasmussen, Peter; Bohm, Aske M

    2012-01-01

    Lactate is shuttled between organs, as demonstrated in the Cori cycle. Although the brain releases lactate at rest, during physical exercise there is a cerebral uptake of lactate. Here, we evaluated the cerebral lactate uptake and release in hypoxia, during exercise and when the two interventions...... were combined. We measured cerebral lactate turnover via a tracer dilution method ([1-(13)C]lactate), using arterial to right internal jugular venous differences in 9 healthy individuals (5 males and 4 females), at rest and during 30 min of submaximal exercise in normoxia and hypoxia (F(i)o(2) 10......%, arterial oxygen saturation 72±10%, mean±SD). Whole-body lactate turnover increased 3.5-fold and 9-fold at two workloads in normoxia and 18-fold during exercise in hypoxia. Although middle cerebral artery mean flow velocity increased during exercise in hypoxia, calculated cerebral mitochondrial oxygen...

  18. Genetic Influences on Physiological and Subjective Responses to an Aerobic Exercise Session among Sedentary Adults

    Directory of Open Access Journals (Sweden)

    Hollis C. Karoly

    2012-01-01

    Full Text Available Objective. To determine whether genetic variants suggested by the literature to be associated with physiology and fitness phenotypes predicted differential physiological and subjective responses to a bout of aerobic exercise among inactive but otherwise healthy adults. Method. Participants completed a 30-minute submaximal aerobic exercise session. Measures of physiological and subjective responding were taken before, during, and after exercise. 14 single nucleotide polymorphisms (SNPs that have been previously associated with various exercise phenotypes were tested for associations with physiological and subjective response to exercise phenotypes. Results. We found that two SNPs in the FTO gene (rs8044769 and rs3751812 were related to positive affect change during exercise. Two SNPs in the CREB1 gene (rs2253206 and 2360969 were related to change in temperature during exercise and with maximal oxygen capacity (VO2 max. The SLIT2 SNP rs1379659 and the FAM5C SNP rs1935881 were associated with norepinephrine change during exercise. Finally, the OPRM1 SNP rs1799971 was related to changes in norepinephrine, lactate, and rate of perceived exertion (RPE during exercise. Conclusion. Genetic factors influence both physiological and subjective responses to exercise. A better understanding of genetic factors underlying physiological and subjective responses to aerobic exercise has implications for development and potential tailoring of exercise interventions.

  19. Different types of compression clothing do not increase sub-maximal and maximal endurance performance in well-trained athletes.

    Science.gov (United States)

    Sperlich, Billy; Haegele, Matthias; Achtzehn, Silvia; Linville, John; Holmberg, Hans-Christer; Mester, Joachim

    2010-04-01

    Three textiles with increasing compressive surface were compared with non-compressive conventional clothing on physiological and perceptual variables during sub-maximal and maximal running. Fifteen well-trained endurance athletes (mean+/-s: age 27.1+/-4.8 years, VO(2max) 63.7+/-4.9 ml x min(-1) x kg(-1)) performed four sub-maximal (approximately 70% VO(2max)) and maximal tests with and without different compression stockings, tights, and whole-body compression suits. Arterial lactate concentration, oxygen saturation and partial pressure, pH, oxygen uptake, and ratings of muscle soreness were recorded before, during, and after all tests. In addition, we assessed time to exhaustion. Sub-maximal (P=0.22) and maximal oxygen uptake (P=0.26), arterial lactate concentration (P=0.16; 0.20), pH (P=0.23; 0.46), oxygen saturation (P=0.13; 0.26), and oxygen partial pressure (P=0.09; 0.20) did not differ between the types of clothing (effect sizes=0.00-0.45). Ratings of perceived exertion (P=0.10; 0.15), muscle soreness (P=0.09; 0.10) and time to exhaustion (P=0.16) were also unaffected by the different clothing (effect sizes=0.28-0.85). This was the first study to evaluate the effect on endurance performance of different types of compression clothing with increasing amounts of compressive surface. Overall, there were no performance benefits when using the compression garments.

  20. The effect of menstruation on chosen physiological and biochemical reactions caused by the physical effort with the submaximal intensity

    Directory of Open Access Journals (Sweden)

    P Zieliński

    2003-03-01

    Full Text Available The aim of this work was to determine the influence of the menstruation phase on changes of respective indicators of the gas exchange and on biochemical parameters of blood during physical efforts with the sub-maximal intensity. Fifteen female students of the Academy of Physical Education took part in the study. Girls were aged from 19 to 22 years old and did not practice sports. The effort tests were conducted in the follicular and luteal phase of two succeeding menstrual cycles. As far the aerobic capacity determination is concerned, one cyclo-ergometric test with graded effort was conducted and it was performed till the “refusal”. It allowed to mark a threshold (TDMA and a maximal level of physiological and biochemical indicators. Basing on the results of the graded test individual loads were determined for every next effort trial (repeated 4 times in every phase of the two succeeding menstrual cycles. The aim of this trial was to evaluate the reaction of women’s constitution on work with the sub-maximal intensity. The above trial consisted on two 10 min efforts divided with the 2 min pause (the first effort with the intensity of 80% of the TDMA threshold, second with the intensity bigger about 30-40% of difference between TDMA and a maximal load established by the graded test. The research did not reveal statistically significant differentiation as considering effort changes of basic physiological and biochemical indicators, determining reaction of women’s organisms on work with the sub- and over- threshold intensity (TDMA. It showed that menstruation has not significant effect on the level of changes of analysed parameters caused by the physical effort with the sub-maximal intensity.

  1. The Limits of Exercise Physiology

    DEFF Research Database (Denmark)

    Gabriel, Brendan M; Zierath, Juleen R

    2017-01-01

    Many of the established positive health benefits of exercise have been documented by historical discoveries in the field of exercise physiology. These investigations often assess limits: the limits of performance, or the limits of exercise-induced health benefits. Indeed, several key findings have...... been informed by studying highly trained athletes, in addition to healthy or unhealthy people. Recent progress has been made in regard to skeletal muscle metabolism and personalized exercise regimes. In this perspective, we review some of the historical milestones of exercise physiology, discuss how...... these inform contemporary knowledge, and speculate on future questions....

  2. Sports drinks, exercise training, and competition.

    Science.gov (United States)

    von Duvillard, Serge P; Arciero, Paul J; Tietjen-Smith, Tara; Alford, Ken

    2008-01-01

    A plethora of investigations examining fluid intake before, during, and after training and competition have suggested that a lack of adequate fluid intake will impair or decrease physical performance. Depending upon the type of training or competition, individuals training for prolonged endurance events should drink fluids containing carbohydrates and electrolytes during and after training or competition. Inadequate hydration will cause significant decrements in performance, increase thermal stress, reduce plasma volume, accelerate fatigue, and possibly cause injuries associated with fluid and sweat loss. However, overdrinking may cause Na+ depletion and in some cases lead to hyponatremia. Maintaining proper hydration before, during, and after training and competition will help reduce fluid loss, maintain performance, lower submaximal exercise heart rate, maintain plasma volume, and reduce heat stress, heat exhaustion, and possibly heat stroke.

  3. Diet and exercise effects on aerobic fitness and body composition in seriously mentally ill adults.

    Science.gov (United States)

    Giannopoulou, Ifigenia; Botonis, Petros; Kostara, Christina; Skouroliakou, Maria

    2014-01-01

    Low exercise capacity and high obesity levels are the main characteristics of people with serious mental illness (SMI). We conducted a pilot study on the effects of a 3-month exercise and dietary intervention on the aerobic capacity and body composition of obese adults with SMI taking Olanzapine, a second generation antipsychotic medication known to induce weight increments. Fifty adults with SMI (15 males and 35 females) followed a 3-month weight loss intervention programme based on exercise and diet. Pre- and post-intervention, a submaximal [Formula: see text]O2 exercise test was performed in order to assess [Formula: see text]O2max anthropometric and body composition measurements were also performed. All participants were obese (body mass index (BMI): 33.61 ± 0.91 kg/m(2)). Pre- and post-intervention, a submaximal [Formula: see text]O2 exercise test on the treadmill was performed in order to assess [Formula: see text]O2max anthropometric and body composition measurements were also performed. Significant reductions in body weight, BMI, body fat and waist circumference were found from pre to post (p diet improves the aerobic capacity and body composition of obese adults with SMI, despite the use of Olanzapine.

  4. Effect of Peer Influence on Exercise Behavior and Enjoyment in Recreational Runners.

    Science.gov (United States)

    Carnes, Andrew J; Petersen, Jennifer L; Barkley, Jacob E

    2016-02-01

    Fitness professionals and popular media sources often recommend exercising with a partner to increase exercise motivation, adherence, intensity, and/or duration. Although competition with peers has been shown to enhance maximal athletic performance, experimental research examining the impact of peer influence on submaximal exercise behavior in adults is limited. The purpose of this study was to determine the effects of the presence of familiar and unfamiliar peers, vs. running alone, on recreational runners' voluntary running duration, distance, intensity, liking (i.e., enjoyment), and ratings of perceived exertion (RPEs). Recreational runners (n = 12 males, n = 12 females) completed 3 experimental trials, each under a different social condition, in a randomized order. Each trial consisted of self-paced running for a duration voluntarily determined by the participant. The 3 social conditions were running alone, with a sex- and fitness-matched familiar peer, or with a sex- and fitness-matched unfamiliar peer. A wrist-worn global positioning system was used to record running duration, distance, and average speed. Liking and RPE were assessed at the end of each trial. Mixed model regression analysis showed no significant effects of social condition (p ≥ 0.40) for any of the dependent variables. The presence of a familiar or unfamiliar peer did not alter recreational runners' running behavior, liking, or perceived exertion during submaximal exercise. However, exercising with others may have other benefits (e.g., reduced attrition) not examined herein.

  5. Effects of the menstrual cycle on exercise performance.

    Science.gov (United States)

    Janse de Jonge, Xanne A K

    2003-01-01

    This article reviews the potential effects of the female steroid hormone fluctuations during the menstrual cycle on exercise performance. The measurement of estrogen and progesterone concentration to verify menstrual cycle phase is a major consideration in this review. However, even when hormone concentrations are measured, the combination of differences in timing of testing, the high inter- and intra-individual variability in estrogen and progesterone concentration, the pulsatile nature of their secretion and their interaction, may easily obscure possible effects of the menstrual cycle on exercise performance. When focusing on studies using hormone verification and electrical stimulation to ensure maximal neural activation, the current literature suggests that fluctuations in female reproductive hormones throughout the menstrual cycle do not affect muscle contractile characteristics. Most research also reports no changes over the menstrual cycle for the many determinants of maximal oxygen consumption (VO2max), such as lactate response to exercise, bodyweight, plasma volume, haemoglobin concentration, heart rate and ventilation. Therefore, it is not surprising that the current literature indicates that VO2max is not affected by the menstrual cycle. These findings suggest that regularly menstruating female athletes, competing in strength-specific sports and intense anaerobic/aerobic sports, do not need to adjust for menstrual cycle phase to maximise performance. For prolonged exercise performance, however, the menstrual cycle may have an effect. Even though most research suggests that oxygen consumption, heart rate and rating of perceived exertion responses to sub-maximal steady-state exercise are not affected by the menstrual cycle, several studies report a higher cardiovascular strain during moderate exercise in the mid-luteal phase. Nevertheless, time to exhaustion at sub-maximal exercise intensities shows no change over the menstrual cycle. The significance of

  6. Prediction of VO2max in Children and Adolescents Using Exercise Testing and Physical Activity Questionnaire Data.

    Science.gov (United States)

    Black, Nate E; Vehrs, Pat R; Fellingham, Gilbert W; George, James D; Hager, Ron

    2016-01-01

    The purpose of this study was to evaluate the use of a treadmill walk-jog-run exercise test previously validated in adults and physical activity questionnaire data to estimate maximum oxygen consumption (VO2max) in boys (n = 62) and girls (n = 66) aged 12 to 17 years old. Data were collected from Physical Activity Rating (PA-R) and Perceived Functional Ability (PFA) questionnaires, a walk-jog-run submaximal treadmill exercise test, and a maximal graded exercise test. Regression analysis resulted in the development of 2 models to predict VO2max. Submaximal exercise test data were used to build the following model (R2 = .73; SEE = 4.59 mL + kg(- 1) + min(- 1)): VO2max (mL + kg(- 1) + min(- 1)) = 26.890+(5.877 × Gender; 0 = female; 1 = male) - (0.782 × Body Mass Index [BMI])+(0.438 × PFA Score) +(2.712 × Treadmill Speed; mph) +(0.746 × Age) +(0.449 × PA-R Score). Maximal exercise test data were used to build the following model (R2 = .83; SEE = 3.63 mL + kg(- 1) + min(- 1)): VO2max (mL + kg(- 1) + min(- 1)) = 10.716+(1.334 × Maximal Treadmill Grade) +(5.203 × Treadmill Speed; mph) +(3.494 × Gender; 0 = female; 1 = male) - (0.413 × BMI) +(0.249 × PFA). The results of this study demonstrate, for the first time, that regression equations that use both exercise data and physical activity questionnaire data can accurately predict VO2max in youth. The submaximal and maximal exercise tests that use self-selected treadmill speeds can be used to assess cardiorespiratory fitness of youth with a wide range of fitness levels.

  7. Prevention: Exercise

    Medline Plus

    Full Text Available ... provide well-rounded core strengthening programs. Simple exercises can be done at home as well. Some specific ... benefit from this exercise... Sagittal Core Strengthening You can stretch and strengthen the low back muscles that ...

  8. Simulation Exercises

    Science.gov (United States)

    Tansey, Pat

    1976-01-01

    Describes five simulation exercises: a problem for a student teacher, an industrial relations game, a series of student problems; an international relations crisis, and a sociological exercise on public and private opinions. (LS)

  9. Prevention: Exercise

    Medline Plus

    Full Text Available ... martial arts all provide well-rounded core strengthening programs. Simple exercises can be done at home as ... doctor or physical therapist to prescribe an exercise program that matches your abilities. Neck Press This is ...

  10. Prevention: Exercise

    Science.gov (United States)

    ... be done at home as well. Some specific core strengthening exercises are described below. If any of the following ... balls, you will experience more benefit from this exercise... Sagittal Core Strengthening You can stretch and strengthen the low ...

  11. Prevention: Exercise

    Medline Plus

    Full Text Available ... strengthening programs. Simple exercises can be done at home as well. Some specific core strengthening exercises are ... a Success Story to Share? | Contact Us SPINE CARE PROVIDERS GO HERE © 2017 North American Spine Society | ...

  12. Prevention: Exercise

    Medline Plus

    Full Text Available ... prescribe an exercise program that matches your abilities. Neck Press This is an isometric exercise to strengthen your neck. Press your palm against your forehead, then use ...

  13. Prevention: Exercise

    Medline Plus

    Full Text Available ... Back Pain Basics Book RESOURCES Patient Information Feature Articles Patient Q&A Success Stories ... Committee Exercise Committee Core Strengthening Many popular forms of exercise focus on ...

  14. Prevention: Exercise

    Medline Plus

    Full Text Available ... Strengthen Your Core! Stretching/Flexibility Aerobic Exercise Cervical Exercise Strength Training for the Elderly Other Back Pack Safety Pregnancy and Back Pain Preventing Osteoporosis Back Pain Basics ...

  15. Exercise Headaches

    Science.gov (United States)

    ... headaches may require emergency medical attention. Symptoms Primary exercise headaches These headaches: Are usually described as throbbing ... sides of the head in most cases Secondary exercise headaches These headaches may cause: The same symptoms ...

  16. Exercise-Induced Muscle Damage and Running Economy in Humans

    Directory of Open Access Journals (Sweden)

    Cláudio de Oliveira Assumpção

    2013-01-01

    Full Text Available Running economy (RE, defined as the energy demand for a given velocity of submaximal running, has been identified as a critical factor of overall distance running performance. Plyometric and resistance trainings, performed during a relatively short period of time (~15–30 days, have been successfully used to improve RE in trained athletes. However, these exercise types, particularly when they are unaccustomed activities for the individuals, may cause delayed onset muscle soreness, swelling, and reduced muscle strength. Some studies have demonstrated that exercise-induced muscle damage has a negative impact on endurance running performance. Specifically, the muscular damage induced by an acute bout of downhill running has been shown to reduce RE during subsequent moderate and high-intensity exercise (>65% VO2max. However, strength exercise (i.e., jumps, isoinertial and isokinetic eccentric exercises seems to impair RE only for subsequent high-intensity exercise (~90% VO2max. Finally, a single session of resistance exercise or downhill running (i.e., repeated bout effect attenuates changes in indirect markers of muscle damage and blunts changes in RE.

  17. Exercise-Induced Muscle Damage and Running Economy in Humans

    Science.gov (United States)

    Assumpção, Cláudio de Oliveira; Lima, Leonardo Coelho Rabello; Oliveira, Felipe Bruno Dias; Greco, Camila Coelho; Denadai, Benedito Sérgio

    2013-01-01

    Running economy (RE), defined as the energy demand for a given velocity of submaximal running, has been identified as a critical factor of overall distance running performance. Plyometric and resistance trainings, performed during a relatively short period of time (~15–30 days), have been successfully used to improve RE in trained athletes. However, these exercise types, particularly when they are unaccustomed activities for the individuals, may cause delayed onset muscle soreness, swelling, and reduced muscle strength. Some studies have demonstrated that exercise-induced muscle damage has a negative impact on endurance running performance. Specifically, the muscular damage induced by an acute bout of downhill running has been shown to reduce RE during subsequent moderate and high-intensity exercise (>65% VO2max). However, strength exercise (i.e., jumps, isoinertial and isokinetic eccentric exercises) seems to impair RE only for subsequent high-intensity exercise (~90% VO2max). Finally, a single session of resistance exercise or downhill running (i.e., repeated bout effect) attenuates changes in indirect markers of muscle damage and blunts changes in RE. PMID:23431253

  18. Is an elevated submaximal heart rate associated with psychomotor slowness in young elite soccer players?

    NARCIS (Netherlands)

    E. Nederhof; C. Visscher; S.L. Schmikli; Koen A.P.M. Lemmink; Michel S. Brink

    2013-01-01

    Abstract The aim of the present study was to find early markers for overreaching that are applicable in sport practice. In a group of elite soccer players aged 15–18, the stress–recovery balance and reaction times before and after exercise were assessed. Overreaching was indicated by an elevated

  19. Isokinetic performance capacity of trunk muscles. Part II: Coefficient of variation in isokinetic measurement in maximal effort and in submaximal effort.

    Science.gov (United States)

    Luoto, S; Hupli, M; Alaranta, H; Hurri, H

    1996-12-01

    It has been claimed that with the aid of isokinetic trunk strength measuring devices it is possible to distinguish true muscular weakness from submaximal effort in the test. This proposition is based on the presumption that in the isokinetic trunk strength test identical performances can only be reproduced by maximal effort. The purpose of this study was to investigate whether it is possible to distinguish maximal effort from submaximal with the aid of the coefficient of variation (CV) in an isokinetic trunk muscle strength test. The study group included 35 (21 male and 14 female) subjects of whom 12 were healthy, 10 had a mild low-back pain and 13 had a more severe chronic low-back pain. The subjects performed five consecutive bendings both with maximal (100%) and submaximal (50%) efforts at a speed of 90 degrees/second. In maximal effort only healthy subjects reached an average level of CV close to 10% both in extension and in flexion. In the chronic low-back pain group the average CV was close to 20%. The difference in CV was statistically significant (p < 0.05-0.02) between the healthy and the chronic low-back pain subjects. In the submaximal effort all health groups had a CV of approximately 20% or more and no significant differences were found. The group of slightly variable measurements (CV = 11-20%) was remarkably large in both the maximal and submaximal effort. The results suggest that an effort with a CV of 11-20% cannot be classified as definitely submaximal or maximal. When the CV is less than 10% the effort can be fairly certainly classified as maximal.

  20. Exercise testing and training in people with Huntington's disease.

    Science.gov (United States)

    Dawes, H; Collett, J; Debono, K; Quinn, L; Jones, K; Kelson, M J; Simpson, S A; Playle, R; Backx, K; Wasley, D; Nemeth, A H; Rosser, A; Izardi, H; Busse, M

    2015-02-01

    To explore exercise response in people with Huntington's disease (HD). Experimental observational study with a randomly allocated subgroup before/after interventional study. Community. People with HD (n=30) and a healthy comparator group (n=20). Thirteen people from the HD group were randomly allocated to an exercise training program. Heart rate (HR) and perceived exertion on the Borg-CR10 scale (RPE) during a submaximal cycle ergometer exercise test (three minute unloaded and nine minute 65%-75%HRmaximum phase). Expired air and lactate measures were available for 8 people with HD during the exercise. A 12 week gym and home walking exercise programme (n=13). People with HD achieved a lower work rate at nine minutes (82±42(0-195) v 107±35(50 -185) Watts (phealthy group and did not achieve a steady state HR during unloaded cycling. People with HD also demonstrated higher than expected lactate at three 2.5±2.5(1.1-8)mmo.L-1 and nine 3.8±1.9(1.2-6.6)mmo.L-1 minutes and respiratory exchange ratio at three 0.78±0.03 (0.74-0.81) and nine minutes 0.94±0.11(0.81-1.15). After exercise training there were no changes observed in HR or RPE responses during the exercise test. There was a large variability in the observed metabolic and physiological responses to exercise in people with HD. The observed exercise responses suggest that altered exercise prescription parameters may be required for people with HD and that exercise response and factors' affecting this requires further investigation. © The Author(s) 2014.

  1. Exercise stress testing. An overview of current guidelines.

    Science.gov (United States)

    Lear, S A; Brozic, A; Myers, J N; Ignaszewski, A

    1999-05-01

    Exercise stress testing (ET) is an inexpensive noninvasive tool that provides valuable cardiopulmonary information in healthy and diseased populations. It is most commonly used for diagnosing coronary artery disease (CAD) and developing appropriate exercise prescriptions (EP). With its widespread use and application, it is imperative that safe and appropriate guidelines and procedures are used, as there are a number of risks associated with testing in a population with or suspected of having CAD. The focus should be on the patient's safety: personnel must be properly trained and aware of all emergency procedures, contra-indications for ET and indications for test termination must be strictly adhered to. Three main types of testing are prevalent: submaximal, maximal and maximal utilising gas exchange. The maximal test is most commonly used, and the submaximal is appropriate for hospitalised patients. Gas exchange data is essential when assessing congestive heart failure and timing for heart transplantation. ET is commonly performed using a treadmill or a bicycle ergometer. The treadmill provides a more familiar exercise modality and has been shown to have greater diagnostic sensitivity than the bicycle ergometer; it is, however, more expensive and requires more space in the testing room. The bicycle ergometer is more appropriate for those individuals who are severely obese or have problems with extended periods of walking. Regardless of the modality used, an appropriate exercise protocol should be used. In North America, the Bruce protocol is the most common. However, the Bruce protocol, and others that estimate exercise capacity based on equations, tend to overestimate exercise capacity. They may be too demanding for those with limited exercise capacity, and too long for those with high exercise capacity. For these people, an exercise protocol that reaches maximal capacity in 8 to 12 minutes using smaller increments in workload should be considered. Once completed

  2. Preventing exercise-induced hypoglycemia in type 1 diabetes using real-time continuous glucose monitoring and a new carbohydrate intake algorithm: an observational field study.

    Science.gov (United States)

    Riddell, Michael C; Milliken, Jill

    2011-08-01

    Real-time (RT) continuous glucose monitoring (CGM) offers the possibility to better manage glucose levels during exercise in active individuals with type 1 diabetes mellitus (T1DM). However, studies have yet to determine the appropriate actions to take when glucose levels are trending toward hypoglycemia. The purpose of this observational field study was to test the effectiveness of RT-GCM and a new carbohydrate intake algorithm designed for maintaining euglycemia during sports. During a 2-week sports camp, 25 adolescents (8-17 years old) with T1DM were fitted with a RT-CGM device and instructed to ingest fast-acting carbohydrates (8-20 g, depending on the concentration of glucose at the time of RT-CGM alert and rates of change in glycemia) when glucose levels were trending toward hypoglycemia. Rates of change in glucose were measured before and after algorithm use, and the incidence of hypoglycemia was documented. With RT-CGM and algorithm use, euglycemia was largely maintained with modest amounts of carbohydrate intake, even when glucose levels were initially dropping at an elevated rate (>0.55 mmol/L per 5 min). Mild biochemical hypoglycemia (3.0-3.9 mmol/L) occurred just twice out of 22 uses of the algorithm (9%) when trend arrows alerted the subjects that glucose levels were dropping. When glucose levels were already below target (carbohydrate being ingested. Average glucose levels during sports in the 60 min following algorithm use were 5.8 ± 1.2 mmol/L, 5.3 ± 1.0 mmol/L, and 6.2 ± 0.8 mmol/L in the 20-, 16-, and 8-g carbohydrate intake protocols when glucose levels were initially on target but dropping toward hypoglycemia. When coupled with RT-CGM, a new carbohydrate intake algorithm prevents hypoglycemia and maintains euglycemia during exercise, particularly if patients ingest carbohydrate when trend arrows alert them of a drop in glycemia.

  3. Exercise addiction

    DEFF Research Database (Denmark)

    Lichtenstein, Mia Beck; Christiansen, Erik; Elklit, Ask

    2014-01-01

    Exercise addiction is characterized by excessive exercise patterns with potential negative consequences such as overuse injuries. The aim of this study was to compare eating disorder symptoms, quality of life, personality traits and attachments styles in exercisers with and without indications...... of exercise addiction. A case-control study with 121 exercisers was conducted. The exercisers were categorized into an addiction group (n=41) or a control group (n=80) on the basis of their responses to the Exercise Addiction Inventory. The participants completed the Eating Disorder Inventory 2, the Short......-Form 36, the NEO Personality Inventory Revised and the Adult Attachment Scale. The addiction group scored higher on eating disorder symptoms, especially on perfectionism but not as high as eating disorder populations. The characteristic personality traits in the addiction group were high levels...

  4. Prescription of aerobic exercise during pregnancy.

    Science.gov (United States)

    Wolfe, L A; Hall, P; Webb, K A; Goodman, L; Monga, M; McGrath, M J

    1989-11-01

    perception of exertion scales being the most logical alternative. Prediction of maximal aerobic power (VO2max) from submaximal work rate/heart rate relationships is also problematic during pregnancy. Other areas of debate include the advisability of initiating a new exercise programme during pregnancy, methods for prevention of fetal hyperthermia, the safety of weight-training/isometric exercise and optimal methods for training of pre/postnatal fitness instructors.

  5. Influence of shoes increasing dorsiflexion and decreasing metatarsus flexion on lower limb muscular activity during fitness exercises, walking, and running.

    Science.gov (United States)

    Bourgit, David; Millet, Guillaume Y; Fuchslocher, Jörg

    2008-05-01

    The aim of the present study was to compare electromyographic activity during fitness exercises, walking, and running among 3 different dorsiflexion shoes (+2 degrees , +4 degrees , and +10 degrees ) and standard shoes (-4 degrees ). The 3 different dorsiflexion shoes tested in this study have a curvature placed in the middle of the sole. This design was specially projected to decrease the metatarsus flexion. Electromyographic activity of 9 lower limb muscles was measured on 12 healthy female subjects during 5 fitness exercises (unload squat, side and front step, submaximal ballistic plantar flexion, and lunge exercise), and during running (10 km x h(-1)) and walking (4.5 km x h(-1)) on a treadmill. EMG signal was analyzed with the root mean square (RMS) and integrated EMG. All RMS data measured during these exercises were expressed as percentages of maximum voluntary isometric contraction. The results show that dorsiflexion affects muscle recruitment and reorganizes the motor pattern. The general tendency was that the tibialis anterior activity increased with dorsiflexion. However, an optimal dorsiflexion existed for various exercises. It is concluded that shoes with moderate dorsiflexion can activate lower limb muscles differently compared with both standard shoes and shoes with large dorsiflexion during submaximal exercises and locomotion.

  6. Middle cerebral artery blood velocity and plasma catecholamines during exercise

    DEFF Research Database (Denmark)

    Pott, F; Jensen, K; Hansen, H

    1996-01-01

    During dynamic exercise, mean blood velocity (Vmean) in the middle cerebral artery (MCA) demonstrates a graded increase to work rate and reflects regional cerebral blood flow. At a high work rate, however, vasoactive levels of plasma catecholamines could mediate vasoconstriction of the MCA...... and thereby elevate Vmean at a given volume flow. To evaluate transcranial Doppler-determined Vmean at high plasma catecholamine levels, seven elite cyclists performed a maximal performance test on a bicycle ergometer. Results were compared with those elicited during five incremental exercise bouts and during...... rhythmic handgrip when plasma catecholamines are low. During rhythmic handgrip the Vmean was elevated by 21 +/- 3% (mean +/- SE), which was not statistically different from that established during moderate cycling. However, at the highest submaximal and maximal work intensities on the bicycle ergometer...

  7. Mesenteric, coeliac and splanchnic blood flow in humans during exercise

    DEFF Research Database (Denmark)

    Perko, M J; Nielsen, H B; Skak, C

    1998-01-01

    1. Exercise reduces splanchnic blood flow, but the mesenteric contribution to this response is uncertain. 2. In nineteen humans, superior mesenteric and coeliac artery flows were determined by duplex ultrasonography during fasting and postprandial submaximal cycling and compared with the splanchnic...... blood flow as assessed by the Indocyanine Green dye-elimination technique. 3. Cycling increased arterial pressure, heart rate and cardiac output, while it reduced total vascular resistance. These responses were not altered in the postprandial state. During fasting, cycling increased mesenteric, coeliac...... decreased by 51 and 31 % (0.49 +/- 0.07 and 0.96 +/- 0.28 l min-1). Splanchnic blood flow values assessed by duplex ultrasound and by dye-elimination techniques were correlated (r = 0.70; P exercise in humans, splanchnic resistance increases and blood flow is reduced following...

  8. Exercise-induced changes in hematocrit and hematocrit/viscosity ratio in male rugby players.

    Science.gov (United States)

    Varlet-Marie, Emmanuelle; Brun, Jean-Frédéric; Raynaud de Mauverger, Eric; Fédou, Christine

    2016-01-01

    We investigated whether the concept of hematocrit/viscosity (h/η) ratio explains the "paradox of hematocrit in athletes", by calculating a "theoretical optimal hematocrit" (i.e., associated with the higher h/η value predicted with Quemada's equation from plasma viscosity, and erythrocyte rigidity index) before and after exercise. 14 rugby players (19-31 yr; weight 65.8-109.2 kg; height 1.7-1.96 m; BMI 21.7-33.1 kg/m2) underwent a standardized submaximal exercise session on cycloergometer corresponding to 225 kjoules over 30 min. The rheologic response to exercise was measured with the MT90 viscometer and the Myrenne aggregometer. After exercise there was an increase in whole blood viscosity (p values of h/η and hematocrit by models may help to interpret the actual values of these parameters. However, these models need to be more extendedly tested and improved.

  9. VO2 kinetics of constant-load exercise following bed-rest-induced deconditioning

    Science.gov (United States)

    Convertino, V. A.; Goldwater, D. J.; Sandler, H.

    1984-01-01

    Previous studies have shown that the oxygen uptake kinetics during exercise and recovery may be changed by alterations in work intensity, prior exercise, muscle group involvement, ambient conditions, posture, disease state, and level of physical conditioning. However, the effects of detraining on oxygen uptake kinetics have not been determined. The present investigation has the objective to determine the effects of deconditioning following seven days of continuous head-down bed rest on changes in steady-state oxygen uptake, O2 deficit, and recovery oxygen uptake during the performance of constant-load exercise. The obtained results may provide support for previous proposals that submaximal oxygen uptake was significantly reduced following bed rest. The major finding was that bed-rest deconditioning resulted in a reduction of total O2 transport/utilization capacity during the transient phase of upright but not supine exercise.

  10. Acute relief of exercise-induced bronchoconstriction by inhaled formoterol in children with persistent asthma

    DEFF Research Database (Denmark)

    Hermansen, Mette Northman; Nielsen, Kim Gjerum; Buchvald, Frederik

    2006-01-01

    -controlled, crossover study of the immediate effect of formoterol, 9 microg, vs terbutaline, 0.5 mg, and placebo administered as dry powder at different study days. Exercise challenge test was used as a model of acute bronchoconstriction. PATIENTS: Twenty-four 7- to 15-year-old children with persistent asthma....... INTERVENTIONS: The children performed standardized treadmill exercise tests, breathing dry air, with a submaximal workload. Study medication was administered 5 min after exercise if FEV1 dropped > or = 15% within 5 min after exercise. FEV1 and forced expiratory flows were measured repeatedly until 60 min after......% of the maximum increase for both. Median times to recovery within 5% of baseline FEV1 were 5.0 min and 7.4 min for formoterol and terbutaline, respectively (p = 0.33). CONCLUSION: Single-dose formoterol, 9 microg, via dry powder inhaler provided an acute bronchodilatory effect similar to terbutaline during EIB...

  11. Guidelines for Setting Up an Extended Field Trip to Florida and the Florida Keys: An Interactive Experiential Training Field Biology Program Consisting of Pretrip Instruction, Search Image Training, Field Exercises, and Observations of Tropical Habitats and Coral Reefs.

    Science.gov (United States)

    Baker, Claude D.; And Others

    The importance of experiential aspects of biological study is addressed using multi-dimensional classroom and field classroom approaches to student learning. This document includes a guide to setting up this style of field experience. Several teaching innovations are employed to introduce undergraduate students to the literature, techniques, and…

  12. What are the dietary protein requirements of physically active individuals? New evidence on the effects of exercise on protein utilization during post-exercise recovery.

    Science.gov (United States)

    Fielding, Roger A; Parkington, Jascha

    2002-01-01

    Exercise and physical activity increase energy expenditure up to 10-fold. This brief review will focus on the effect of exercise on protein requirements. Evidence has accumulated that amino acids are oxidized as substrates during prolonged submaximal exercise. In addition, studies have determined that both endurance and resistance training exercise increase skeletal muscle protein synthesis and breakdown in the post-exercise recovery period. Studies using nitrogen balance have further confirmed that protein requirements for individuals engaged in regular exercise are increased. The current recommended intakes of protein for strength and endurance athletes are 1.6 to 1.7 g/kg and 1.2 to 1.4 g/kg per day, respectively. Presently, most athletes consume an adequate amount of protein in their diet. The timing and nutritional content of the post-exercise meal, although often overlooked, are known to have synergistic effects on protein accretion after exercise. New evidence suggests that individuals engaging in strenuous activity consume a meal rich in amino acids and carbohydrate soon after the exercise bout or training session.

  13. Effect of music tempo on exercise performance and heart rate among young adults.

    Science.gov (United States)

    Thakare, Avinash E; Mehrotra, Ranjeeta; Singh, Ayushi

    2017-01-01

    Music captures attention, triggers a range of emotions, alters or regulates mood, increases work output, heightens arousal, induces states of higher functioning, reduces inhibitions and encourages rhythmic movement. Music has ergo-genic effect as well, it increases exercise performance, delays fatigue and increases performance and endurance, power and strength. Our study tried to evaluate the effect of music on exercise performance in young untrained subjects. In this study, we tested the effect of music on sub maximal exercise performance time duration in young adults. 25 Male and 25 females were subjected to standard submaximal exercise with and without music. Resting HR and Max. HR during exercise and the exercise time duration was recorded. Total exercise duration in whole group with music (37.12 ± 16.26** min) was significantly greater than exercise duration without music (22.48 ± 10.26 min). Males (42.4 ± 15.6** min) outperformed significantly better than females (31.84 ± 15.48 min). Also, we observed statistically significant higher values of Maximal heart rate with music than without music. But there was no significant correlation between duration of exercise, music and change in Heart rate. We can conclude that Music increases duration of exercise in both sexes and hence endurance.

  14. Oxygen uptake kinetics of constant-load work - Upright vs. supine exercise

    Science.gov (United States)

    Convertino, V. A.; Goldwater, D. J.; Sandler, H.

    1984-01-01

    Supine and upright positions were used in a comparitive study of the effects of constant load exercise on oxygen uptake (VO2), O2 deficit, steady-state VO2 and VO2 following recovery from constant load work. Ten male subjects (36-40 yr.) performed one submaximal exercise test in the supine and one test in the upright position consisting of 5 min rest and 5 min cycle ergometer exercise at 700 kg/min followed by ten minutes of recovery. It is found that the significant difference in VO2 kinetics during exercise in the upright compared to supine position resulted from changes in oxygen transport and utilization mechanisms rather than changes in mechanical efficiency. To the extent that data measured in the supine position can be used to estimate physiological responses to zero gravity, it is suggested that limitation of systemic O2 consumption may be the result of slow rates of oxygen uptake during transient periods of muscular work. Significant reductions in the rate of steady-state VO2 attainment at submaximal work intensities may produce an onset of muscle fatigue and exhaustion.

  15. Assessment of muscle endurance of the knee extensor muscles in adolescents with spastic cerebral palsy using a submaximal repetitions-to-fatigue protocol.

    Science.gov (United States)

    Eken, Maaike M; Dallmeijer, Annet J; Doorenbosch, Caroline A; Dekkers, Hurnet; Becher, Jules G; Houdijk, Han

    2014-10-01

    To compare muscle endurance in adolescents with spastic cerebral palsy (CP) with typically developing (TD) peers using a submaximal repetitions-to-fatigue (RTF) protocol. Cross sectional. Human motion laboratory. Adolescents with spastic CP (n=16; Gross Motor Function Classification System levels I or II) and TD adolescents (n=18) within the age range of 12 to 19 years old. Not applicable. Each participant performed 3 RTF tests at different submaximal loads, ranging from 50% to 90% of their maximal voluntary knee extension torque. The relation between the number of repetitions (repetition maximum [RM]) and imposed submaximal relative (percent of maximal voluntary torque [%MVT]) and absolute (Nm/kg) torque was quantified. To compare adolescents with CP with TD adolescents, a mixed linear model was used to construct load endurance curves. Surface electromyography of quadriceps muscles was measured to assess changes in normalized amplitude and median frequency (MF) as physiological indicators of muscle fatigue. Adolescents with CP showed a larger decrease in %MVT per RM than TD adolescents (Pmuscles in all tests for both groups. Electromyographic MF decreased significantly (Pmuscle fatigue were reached. Adolescents with CP show slightly lower muscle endurance compared with TD adolescents on a submaximal RTF protocol, which is in contrast with earlier findings in a maximal voluntary fatigue protocol. Accordingly, adolescents with CP have a reduced capacity to endure activities at similar relative loads compared with TD adolescents. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  16. Prevention: Exercise

    Medline Plus

    Full Text Available ... Steroid Injections Lumbar Zygapophysical (Facet) Joint Injections PREVENTION Lifestyle Choices 10 Tips for a Healthy Back Smoking Weight Patient Safety Exercise Strengthening Strengthen ...

  17. Prevention: Exercise

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    Full Text Available ... Exercises Electrothermal Modalities Ergonomic Changes Hydrotherapy Manual Therapy Physical Therapy Postural Training Traction Watchful Waiting and Education Injection Treatments for Spinal Pain Epidural Steroid Injections ...

  18. Effect of acute and regular exercise on antioxidative enzymes, tissue damage markers and membran lipid peroxidation of erythrocytes in sedentary students

    OpenAIRE

    Aslan, Recep

    2014-01-01

    15 healthy sedentary men, 19-25 years old an did not have any programmed physical activity, were studied. The subjects were asked to run submaximal 15-20 min every day for 5 weeks. Erythrocyte lipid peroxidation, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and glucose and uric acid levels were determined in blood samples which were taken before and immediately after acute exercise and after the end of 5-week training program. Malonaldialdehyde (MDA), sing...

  19. Effect of chain wheel shape on crank torque, freely chosen pedal rate, and physiological responses during submaximal cycling

    DEFF Research Database (Denmark)

    Hansen, Ernst Albin; Jensen, Kurt; Hallén, Jostein

    2009-01-01

    . A musculoskeletal simulation model supported the idea that a contributing factor to the observed difference in blood lactate concentration may be slightly reduced muscle activity around the phase where peak crank torque occurs during cycling with the Biopace chain wheel. In that particular phase of the crank......The development of noncircular chain wheels for the enhancement of cycling performance has been in progress for a long time and continues apace. In this study we tested whether submaximal cycling using a non-circular (Biopace) versus a circular chain wheel resulted in lower peak crank torque...... chain wheel at 180 W at 65 and 90 rpm for recording of crank torque profiles, and at their freely chosen pedal rate for recording of pedal rate and metabolic response, including oxygen uptake and blood lactate concentration. Crank torque profiles were similar between the two chain wheels during cycling...

  20. Torque decrease during submaximal evoked contractions of the quadriceps muscle is linked not only to muscle fatigue.

    Science.gov (United States)

    Matkowski, Boris; Lepers, Romuald; Martin, Alain

    2015-05-01

    The aim of this study was to analyze the neuromuscular mechanisms involved in the torque decrease induced by submaximal electromyostimulation (EMS) of the quadriceps muscle. It was hypothesized that torque decrease after EMS would reflect the fatigability of the activated motor units (MUs), but also a reduction in the number of MUs recruited as a result of changes in axonal excitability threshold. Two experiments were performed on 20 men to analyze 1) the supramaximal twitch superimposed and evoked at rest during EMS (Experiment 1, n = 9) and 2) the twitch response and torque-frequency relation of the MUs activated by EMS (Experiment 2, n = 11). Torque loss was assessed by 15 EMS-evoked contractions (50 Hz; 6 s on/6 s off), elicited at a constant intensity that evoked 20% of the maximal voluntary contraction (MVC) torque. The same stimulation intensity delivered over the muscles was used to induce the torque-frequency relation and the single electrical pulse evoked after each EMS contraction (Experiment 2). In Experiment 1, supramaximal twitch was induced by femoral nerve stimulation. Torque decreased by ~60% during EMS-evoked contractions and by only ~18% during MVCs. This was accompanied by a rightward shift of the torque-frequency relation of MUs activated and an increase of the ratio between the superimposed and posttetanic maximal twitch evoked during EMS contraction. These findings suggest that the torque decrease observed during submaximal EMS-evoked contractions involved muscular mechanisms but also a reduction in the number of MUs recruited due to changes in axonal excitability. Copyright © 2015 the American Physiological Society.

  1. Effects of tiotropium on sympathetic activation during exercise in stable chronic obstructive pulmonary disease patients

    Directory of Open Access Journals (Sweden)

    Kitada S

    2012-05-01

    Full Text Available Kenji Yoshimura, Ryoji Maekura, Toru Hiraga, Seigo Kitada, Keisuke Miki, Mari Miki, Yoshitaka TateishiDepartment of Respiratory Medicine, Toneyama National Hospital, Osaka, JapanBackground: Tiotropium partially relieves exertional dyspnea and reduces the risk of congestive heart failure in chronic obstructive pulmonary disease (COPD patients. However, its effect on the sympathetic activation response to exercise is unknown.Aims: This study aimed to determine whether tiotropium use results in a sustained reduction in sympathetic activation during exercise.Methods: We conducted a 12-week, open-label (treatments: tiotropium 18 µg or oxitropium 0.2 mg × 3 mg, crossover study in 17 COPD patients. Treatment order was randomized across subjects. The subjects underwent a pulmonary function test and two modes of cardiopulmonary exercise (constant work rate and incremental exercise testing using a cycle ergometer, with measurement of arterial catecholamines after each treatment period.Results: Forced expiratory volume in 1 second and forced vital capacity were significantly larger in the tiotropium treatment group. In constant exercise testing, exercise endurance time was longer, with improvement in dyspnea during exercise and reduction in dynamic hyperinflation in the tiotropium treatment group. Similarly, in incremental exercise testing, exercise time, carbon dioxide production, and minute ventilation at peak exercise were significantly higher in the tiotropium treatment group. Plasma norepinephrine concentrations and dyspnea intensity were also lower during submaximal isotime exercise and throughout the incremental workload exercise in the tiotropium treatment group.Conclusion: Tiotropium suppressed the increase of sympathetic activation during exercise at the end of the 6-week treatment, as compared with the effect of oxipropium. This effect might be attributed to improvement in lung function and exercise capacity and reduction in exertional dyspnea

  2. Prevention: Exercise

    Medline Plus

    Full Text Available ... be done at home as well. Some specific core strengthening exercises are described below. If any of the following ... balls, you will experience more benefit from this exercise... Sagittal Core Strengthening You can stretch and strengthen the low ...

  3. Prevention: Exercise

    Medline Plus

    Full Text Available ... slow full movements. Repeat 10-15 times, to fatigue... Abdominal Exercise Lay on your back with both knees bent. ... Return leg and extend other leg. Repeat to fatigue, about 10-15 repetitions at a slow ... training is exercise done against something providing resistance. It can be ...

  4. Prevention: Exercise

    Medline Plus

    Full Text Available ... core strengthening, or building the muscles that provide support for your body. Pilates, yoga and martial arts all provide well-rounded core strengthening programs. Simple exercises can be done at home as well. Some specific core strengthening exercises are ...

  5. Cardiovascular adaptations in weightlessness: The influence of in-flight exercise programs on the cardiovascular adjustments during weightlessness and upon returning to Earth

    Science.gov (United States)

    Bennett, C. H.

    1981-01-01

    The effect of in-flight exercise programs on astronauts' cardiovascular adjustments during spaceflight weightlessness and upon return to Earth was studied. Physiological changes in muscle strength and volume, cardiovascular responses during the application of lower body negative pressure, and metabolic activities during pre-flight and flight tests were made on Skylab crewmembers. The successful completion of the Skylab missions showed that man can perform submaximal and maximal aerobic exercise in the weightless enviroment without detrimental trends in any of the physiologic data. Exercise tolerance during flight was unaffected. It was only after return to Earth that a tolerance decrement was noted. The rapid postflight recovery of orthostatic and exercise tolerance following two of the three Skylab missions appeared to be directly related to total in-flight exercise as well as to the graded, regular program of exercise performed during the postflight debriefing period.

  6. Cardiovascular responses in older adults with total knee arthroplasty at rest and with exercise on a positive pressure treadmill.

    Science.gov (United States)

    Webber, Sandra C; Horvey, Karla J; Yurach Pikaluk, Madison T; Butcher, Scott J

    2014-03-01

    We investigated cardiovascular responses at rest and during submaximal exercise on a lower body positive pressure treadmill in older adults with total knee arthroplasty (TKA). Twenty-four adults (mean age 64.6 ± 7.9 SD) with unilateral TKA participated (median time since surgery 8.0 weeks). Heart rate and blood pressure responses were measured at rest standing on the positive pressure treadmill with 0, 10, 20, and 30 mmHg applied. Heart rate, blood pressure, oxygen consumption, minute ventilation, knee pain and perceived exertion were measured during submaximal exercise tests (0 and 40% body weight support) conducted 1 week apart. At rest there were no differences in blood pressure across different treadmill pressures, but heart rate was significantly lower when 30 mmHg was applied compared to ambient pressure conditions (P exercise test stages with 0% body weight support (maximum speed 2.5 mph, 0% incline) and 6.4 stages with 40% body weight support (maximum speed 3.0 mph, 10% incline). During exercise, heart rate, systolic blood pressure, oxygen consumption, and minute ventilation were lower when 40% body weight support was provided for a given test stage (P exercise test stages (P < 0.05). Provision of body weight support allowed TKA patients to walk at faster speeds and/or to tolerate greater incline with relatively lower levels of heart rate, blood pressure, and oxygen consumption.

  7. Transcutaneous electrical nerve stimulation reduces exercise-induced perceived pain and improves endurance exercise performance.

    Science.gov (United States)

    Astokorki, Ali H Y; Mauger, Alexis R

    2017-03-01

    Muscle pain is a natural consequence of intense and prolonged exercise and has been suggested to be a limiter of performance. Transcutaneous electrical nerve stimulation (TENS) and interferential current (IFC) have been shown to reduce both chronic and acute pain in a variety of conditions. This study sought to ascertain whether TENS and IFC could reduce exercise-induced pain (EIP) and whether this would affect exercise performance. It was hypothesised that TENS and IFC would reduce EIP and result in an improved exercise performance. In two parts, 18 (Part I) and 22 (Part II) healthy male and female participants completed an isometric contraction of the dominant bicep until exhaustion (Part I) and a 16.1 km cycling time trial as quickly as they could (Part II) whilst receiving TENS, IFC, and a SHAM placebo in a repeated measures, randomised cross-over, and placebo-controlled design. Perceived EIP was recorded in both tasks using a validated subjective scale. In Part I, TENS significantly reduced perceived EIP (mean reduction of 12%) during the isometric contraction (P = 0.006) and significantly improved participants' time to exhaustion by a mean of 38% (P = 0.02). In Part II, TENS significantly improved (P = 0.003) participants' time trial completion time (~2% improvement) through an increased mean power output. These findings demonstrate that TENS can attenuate perceived EIP in a healthy population and that doing so significantly improves endurance performance in both submaximal isometric single limb exercise and whole-body dynamic exercise.

  8. DIURNAL VARIATION OF HAEMOSTATIC RESPONSE TO EXERCISE IN YOUNG SEDENTARY MALES

    Directory of Open Access Journals (Sweden)

    Marefat Siahkouhian

    2013-04-01

    Full Text Available The aim of this study was to evaluate diurnal variations in the haemostatic response to submaximal exercise performed by young, sedentary men. Fifteen healthy young sedentary males aged 25.6 ± 1.34 (mean ± SD years performed two exercise sessions, morning and evening, at 70�0of maximal oxygen consumption (VO2max on a cycle ergometer for 30 min. Platelet count (PC, activated partial thromboplastin time (aPTT, prothrombin time (PT, fibrinogen, tissue plasminogen activator (tPA and plasminogen activator inhibitor-1 (PAI-1 activity were measured as dependent variables. Exercise produced significant increases in PC and fibrinogen for both sessions (P≤0.05, which returned to the resting values after recovery only in the evening session. APTT and PT shortened immediately after exercise, which remained after recovery for both sessions (P≤0.01. Exercise presented significant increases in tPA activity (P≤0.001, which returned to the baseline after recovery in both exercises. PAI-1 activity was significantly higher during the morning than evening (P≤0.05, but no longer demonstrated exercise-related changes. It was found that exercise caused activation of both coagulation and fibrinolysis processes, partly related to the time of the day when the exercise was performed.

  9. Diurnal variation of haemostatic response to exercise in young sedentary males.

    Science.gov (United States)

    Siahkouhian, M; Khodadadi, D; Bolboli, L

    2013-06-01

    The aim of this study was to evaluate diurnal variations in the haemostatic response to submaximal exercise performed by young, sedentary men. Fifteen healthy young sedentary males aged 25.6 ± 1.34 (mean ± SD) years performed two exercise sessions, morning and evening, at 70% of maximal oxygen consumption ([Formula: see text]O2max) on a cycle ergometer for 30 min. Platelet count (PC), activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen, tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) activity were measured as dependent variables. Exercise produced significant increases in PC and fibrinogen for both sessions (P ≤ 0.05), which returned to the resting values after recovery only in the evening session. APTT and PT shortened immediately after exercise, which remained after recovery for both sessions (P ≤ 0.01). Exercise presented significant increases in tPA activity (P ≤ 0.001), which returned to the baseline after recovery in both exercises. PAI-1 activity was significantly higher during the morning than evening (P ≤ 0.05), but no longer demonstrated exercise-related changes. It was found that exercise caused activation of both coagulation and fibrinolysis processes, partly related to the time of the day when the exercise was performed.

  10. The effect of 1 year of Alagebrium and moderate-intensity exercise training on left ventricular function during exercise in seniors: a randomized controlled trial.

    Science.gov (United States)

    Carrick-Ranson, Graeme; Fujimoto, Naoki; Shafer, Keri M; Hastings, Jeffrey L; Shibata, Shigeki; Palmer, M Dean; Boyd, Kara; Levine, Benjamin D

    2016-08-01

    Sedentary aging leads to left ventricular (LV) and vascular stiffening due in part to advanced glycation end-products (AGEs) cross-linking of extracellular matrix proteins. Vigorous lifelong exercise ameliorates age-related cardiovascular (CV) stiffening and enhances exercise LV function, although this effect is limited when exercise is initiated later in life. We hypothesized that exercise training might be more effective at improving the impact of age-related CV stiffening during exercise when combined with an AGE cross-link breaker (Alagebrium). Sixty-two seniors (≥60 yr) were randomized into four groups: sedentary + placebo, sedentary + Alagebrium, exercise + placebo, and exercise + Alagebrium for 1 yr. Moderate-intensity aerobic exercise was performed 3-4 sessions/wk; controls underwent similar frequency of yoga/balance training. Twenty-four similarly-aged, lifelong exercisers (4-5 sessions/wk) served as a comparator for the effect of lifelong exercise on exercising LV function. Oxygen uptake (Douglas bags), stroke index (SI; acetylene rebreathing), and effective arterial elastance (Ea) were collected at rest and submaximal and maximal exercise. Maximum O2 uptake (23 ± 5 to 25 ± 6 ml·kg(-1)·min(-1)) increased, while SI (35 ± 11 to 39 ± 12 ml/m(2)) and Ea (4.0 ± 1.1 to 3.7 ± 1.2 mmHg·ml(-1)·m(-2)) were improved across all conditions with exercise, but remained unchanged in controls (exercise × time, P ≤ 0.018). SI or Ea were not affected by Alagebrium (medication × time, P ≥ 0.468) or its combination with exercise (interaction P ≥ 0.252). After 1 yr of exercise plus Alagebrium, exercise SI and Ea remained substantially below that of lifelong exercisers (15-24 and 9-22%, respectively, P ≤ 0.415). In conclusion, Alagebrium plus exercise had no synergistic effect on exercise LV function and failed to achieve levels associated with lifelong exercise, despite a similar exercise frequency.

  11. Adjunctive Use of Noninvasive Ventilation During Exercise in Patients With Decompensated Heart Failure.

    Science.gov (United States)

    Moraes, Igor Gutierrez; Kimoto, Karen Mota; Fernandes, Marcos Brandmuller; Grams, Samantha Torres; Yamaguti, Wellington Pereira

    2017-02-01

    Noninvasive ventilation (NIV) as an adjunct strategy for increasing exercise tolerance has been widely investigated in patients with pulmonary diseases. To our knowledge, there are no studies that have used NIV during exercise in patients with decompensated heart failure (HF). The aim of this study was to evaluate the effects of NIV on exercise tolerance in hospitalized patients with decompensated HF. Thirteen patients (77 ± 15 years) with a mean left ventricular ejection fraction of 35 ± 15% were included. Patients underwent 2 submaximal exercise tests with constant load for lower limbs using a portable cycle ergometer. Tests were performed on the same day with a 60-minute interval between each one, using a randomized crossover design: sham ventilation (continuous positive airway pressure mode, 4 cm H2O) and intervention situation (NIV in bilevel mode). Primary outcome was the endurance time performed during exercise tests with constant load. Submaximal exercise with NIV in bilevel mode improved endurance time (7.2 ± 2.7 minutes) compared to the tests performed with continuous positive airway pressure (5.1 ± 1.5 minutes; p = 0.008). Increase in endurance time (Δ time) with bilevel test showed a significant correlation with reduction in the slope of dyspnea (Δ Borg) over time (r = -0.73; p = 0.004). There was a significant correlation between endurance time in bilevel tests and maximum inspiratory pressure % predicted (r = 0.68; p = 0.02). In conclusion, NIV was effective in increasing exercise tolerance in hospitalized patients with decompensated HF. (ClinicalTrials.gov registration NCT02122848). Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Equine sweat composition: effects of adrenaline infusion, exercise and training.

    Science.gov (United States)

    McConaghy, F F; Hodgson, D R; Evans, D L; Rose, R J

    1995-11-01

    Significant alterations in plasma electrolyte concentrations have been reported in horses following prolonged exercise, resulting from loss of hypertonic sweat. Sweat was collected from 10 horses undergoing a 10 week training programme; 5 at moderate intensity, to speeds of 10 m/s and 5 at low intensity, to speeds of 5 m/s. Sweat was collected from 2 sites in response to a submaximal exercise test (30 min at 50% VO2max and during an adrenaline infusion (dose mean +/- s.d.; 0.3 +/- 0.05 g/kg over 30 min). Sweat samples were analysed for sodium, chloride, potassium, protein, magnesium, calcium and urea concentrations. Sweat produced in response to exercise and adrenaline infusion was hypertonic and showed no significant differences in composition following training. However, the [NaCl] of sweat rose with increased duration of sweating. Sweat produced in response to adrenaline infusion was more dilute than that produced in response to exercise, which may be related to sympathetic outflow during exercise.

  13. Nitrate Supplementation, Exercise, and Kidney Function: Are There Detrimental Effects?

    Science.gov (United States)

    Carpentier, Alain; Stragier, Séverine; Bréjeon, Camille; Poortmans, Jacques R

    2015-07-01

    Recently, dietary supplementation with inorganic nitrate (NO3) has been proposed to endurance athletes to increase their performance. However, it has been suggested that an excess of NO3 might be harmful. The present study analyzed the effect of NO3 supplementation on kidney function. Thirteen young male subjects performed a 20-min cycling exercise at 85% of the maximal oxygen capacity. Seven days before exercise, the subjects ingested either a placebo (Pl) or 450 mg of potassium nitrate (PN) per day. Venous blood samples and urine collections were collected before and immediately after exercise and after 60 min of recovery. Glomerular filtration rates (GFR) and clearances (Cl) were calculated from serum content and urine output for creatinine (Crn), albumin (Alb), and urea. Under resting conditions, GFR and all clearance measures did not differ between Pl and PN. Immediately after exercise, GFR remained stable in both Pl and PN, whereas Cl-urea decreased significantly (P urea returned to initial values in placebo and nitrate supplementation. Alb output and Cl-Alb remained enhanced under PN conditions. These results mainly indicate that dietary nitrate supplementation over a week does not induce any specific kidney function modifications either at rest or during sustained submaximal exercise as compared with Pl.

  14. Cold exposure increases exercise-induced oxidative stress.

    Science.gov (United States)

    Martarelli, D; Cocchioni, M; Scuri, S; Spataro, A; Pompei, P

    2011-06-01

    We determined the combined effects of cold and exercise on oxidative stress during submaximal exercise. Sixteen amateur male cyclists pedaled at a constant speed corresponding to 85% of maximal HR as determined in normal conditions. Eight athletes pedaled indoors at 23 °C while 8 athletes pedaled outdoors at a temperature of 4-6 °C. We then evaluated the levels of reactive oxygen metabolites and plasma levels of antioxidants after exercise. Performing a physical task in cold conditions increased the free radical production, as demonstrated by the augmented levels of reactive oxygen metabolites and the concomitant decrease of plasma levels of antioxidants in outdoors cyclists as compared to indoors cyclists. The overall ANOVA and the post-hoc comparisons revealed a significant exercise and temperature effect. The mean level of reactive oxygen metabolites in athletes who exercised indoors was significantly lower than that of the outdoor athletes. Moreover, the outdoors group presented plasma levels of antioxidants significantly lower than those of the indoors group. Since several sports are performed outdoors during the winter season, the increased risk of oxidative stress in cold conditions must be considered in these disciplines. Cyclists, football and rugby players, and runners are all affected by the elevation in oxygen radicals induced by cold and should take appropriate precautions, such as specific antioxidant integration.

  15. Influence of Dietary Acid Load on Exercise Performance.

    Science.gov (United States)

    Applegate, Catherine; Mueller, Mackenzie; Zuniga, Krystle E

    2017-06-01

    Diet composition can affect systemic pH and acid-base regulation, which may in turn influence exercise performance. An acidic environment in the muscle impairs performance and contributes to fatigue; therefore, current trends in sports nutrition place importance on maximizing the alkalinity of the body with ergogenic aids and dietary strategies. This review examines the evidence on the effects of dietary manipulations on acid load and exercise performance. Ten studies that investigated the effect of high versus low dietary acid loads on athletic performance generally identified that low dietary acid loads increased plasma pH, but did not consistently improve exercise performance at maximal or submaximal exercise intensities. In addition, the few studies conducted have several limitations including lack of female subjects and use of exercise tests exclusive to cycling or treadmill running. Although the research does not strongly support a performance benefit from low dietary acid loads, a more alkaline dietary pattern may be beneficial for overall health, as dietary induced acidosis has been associated with greater risk of cardiovascular disease and bone disease. The review includes dietary recommendations for athletes to reduce dietary acid load while still meeting sports nutrition recommendations.

  16. Variação da pressão intraocular após teste submáximo de força no treinamento resistido Intraocular pressure variation after submaximal strength test in resistance training

    Directory of Open Access Journals (Sweden)

    Marcelo Conte

    2009-06-01

    Full Text Available OBJETIVO: Verificar a variação da pressão intraocular (PIO decorrente da aplicação do teste de predição para uma repetição máxima (1RM. MÉTODOS: Foram avaliados em estudo observacional 145 calouros (22,04 ± 4,17 anos; de ambos os sexos do curso de Educação Física da Escola Superior de Educação Física de Jundiaí (ESEFJ. Os critérios de exclusão foram: opacidade de meios, alteração de globo ocular ou ausência de globo ocular. Todos os participantes assinaram o Termo de Consentimento Livre e Esclarecido. A avaliação da PIO foi determinada por duas medidas consecutivas com o tonômetro de Perkins: i pré-teste: antes do teste de 1RM e ii pós-teste: logo após a realização do teste. O teste de 1RM consistiu em predizer o valor de uma repetição máxima através de repetições até a fadiga. Foram utilizados os seguintes exercícios resistidos: supino, pulley dorsal, desenvolvimento, rosca direta e leg press 45º. Como procedimento estatístico foi empregado o teste "t" de Student pareado. RESULTADOS: Ocorreu redução da PIO após a realização do teste de predição de 1RM: 13,48 ± 3,32 vs.10,20 ± 3,72 mmHg (pPURPOSE: To verify the intraocular pressure (IOP after sub-maximal strength test. METHODS: 145 Physical Education freshmen (22.04 ± 4.17 years old; female and male from Superior Physical Education School of Jundiaí (ESEFJ were evaluated in an observacional study. The exclusion criteria were: media opacity and eyeball absence or changes. All subjects agreed to take part in this research and signed up the Informed Consent. IOP was measured by Perkins tonometer: i pretest: just before the submaximal strength test performance and ii post-test: immediately after the strength test. The strength test consisted in the one-repetition-maximum-assessment through repetition until fatigue. Resistance training exercises such as bench press, pulley dorsal high, shoulder press, arm curl and leg press 45º were performed

  17. Effects of leg strength and bicycle ergometry exercise on cardiovascular deconditioning after 30-day head-down bed rest

    Science.gov (United States)

    Wu, Bin; Liu, Yusheng; Sun, Hongyi; Zhao, Dongming; Wang, Yue; Wu, Ping; Ni, Chengzhi

    2010-10-01

    The purpose of this study is to determine if the intermittent leg muscular strength exercise and bicycle ergometry exercise could attenuate cardiovascular deconditioning induced by prolonged -6° head-down bed rest (HDBR). Fifteen male subjects were randomly allocated into group A ( n=5, 30 days HDBR without exercise), group B ( n=5, 30 days HDBR with leg muscular strength exercise) and group C ( n=5, 30 days HDBR with bicycle ergometry exercise). The orthostatic tolerance (OT) was determined by +75°/20 min head-up tilt (HUT) test and the submaximal exercise capacity was determined by bicycle ergometry before and after HDBR. The results were as follows: (1) Compared with that before HDBR, OT time decreased dramatically by 57.6% ( pexercise time decreased significantly by 17.7% ( p0.77) in group C. (3) compared with that before HDBR, the changes of heart rate (HR) and blood pressure were slightly improved in group B and C, while deteriorated in group A during orthostatic test and exercise test after HDBR. The results indicate that leg muscular strength exercise and bicycle ergometry exercise could partially attenuate the cardiovascular deconditioning induced by 30 d HDBR, and the latter exercise training could fully provide the protection for the loss of exercise capacity.

  18. Rotator Cuff Exercises

    Science.gov (United States)

    ... Home Prevention and Wellness Exercise and Fitness Injury Rehabilitation Rotator Cuff Exercises Rotator Cuff Exercises Share Print Rotator Cuff ... Best Rotator Cuff ExercisesNational Institutes of Health: MedlinePlus, ... and WellnessTags: Exercise Prescription, prevention, Shoulder Problems, ...

  19. Exercise and Posture

    Science.gov (United States)

    ... About Spondylitis › Treatment Information › Exercise & Posture Print Page Exercise Exercise is an integral part of any spondylitis ... For First Responders For Chiropractors Research Article Archive Exercise Guidelines Having an exercise program that accomplishes your ...

  20. INFLUENCE OF MODERATE TRAINING ON GAIT AND WORK CAPACITY OF FIBROMYALGIA PATIENTS: A PRELIMINARY FIELD STUDY

    Directory of Open Access Journals (Sweden)

    Michael Pierrynowski

    2002-12-01

    Full Text Available This field study examined the influence of moderate intensity training on gait patterns and work capacity of individuals with fibromyalgia syndrome (FS. FS is a chronic condition of unknown etiology, characterized by muscle tenderness, pain and stiffness and often accompanied by depression and fatigue which seems to occur primarily in middle aged females. There is no known cure for FS but treatment often includes a prescription of mild exercise. Few studies have evaluated the effectiveness of mild exercise on work capacity and gait patterns in FS patients. Participants were 14 females (age 47.0± 7.6 y who participated in a 10 wk community based aerobic, strength and stretching program designed for FS individuals. Subjects were evaluated pre- and post-program and at a 2 month follow up. Work capacity was estimated by a sub-maximal PWC 170 cycle ergometer test and a Borg perceived exertion scale. Gait was assessed using OptoTrack three dimensional kinematics with 16 channel analogue data acquisition system. Trunk flexibility was also assessed. No significant change in estimated work capacity or flexibility was seen between pre- post- and follow up times. Nevertheless, a significant increase in self selected walking speed (p < 0.05 and a trend toward a more normal gait pattern that was sustained in the follow up testing was noted. We had previously also reported a significant improvement in muscle pain and other fibromyalgia symptoms in this population consequent to the training program. It was concluded that mild exercise training that does not influence work capacity or trunk flexibility can nevertheless positively influence gait mechanics and fibromyalgia symptoms in female FS patients

  1. Comparison of cardiovascular adaptations to long-term arm and leg exercise in wheelchair athletes versus long-distance runners.

    Science.gov (United States)

    Price, D T; Davidoff, R; Balady, G J

    2000-04-15

    The effect of long-term arm exercise on cardiac morphology and function is unknown. To study these effects, highly trained wheelchair athletes were compared with long-distance runners and controls. In addition, the wheelchair athletes were compared with the long-distance runners to determine if long-term leg exercise confers a training effect during the performance of dynamic arm exercise. The study included 31 male subjects (mean age of 33+/-5 years), who comprised 3 groups matched for age and weight: wheelchair athletes (n = 9), long-distance runners (n = 12), and healthy controls (n = 10). All underwent echocardiography at rest and arm ergometry exercise testing with expiratory gas analysis. The peak work rate during arm exercise was highest among the wheelchair athletes, and was significantly higher in both groups of trained athletes compared with the control group (pRunners demonstrated a significantly lower submaximal heart rate response to arm exercise compared with wheelchair and control subjects. Wheelchair athletes had increased left ventricular (LV) volume and mass by echocardiography compared with controls, but not to the same degree as that of runners. Although chamber dimensions and wall thickness did not differ among the groups, the LV volume index tended to be largest in the runners. Doppler indexes of diastolic LV filling were similar between the trained and untrained subjects. These data demonstrate that both long-term arm and leg exercise yield increases in LV volume and mass compared with untrained control subjects, although to a lesser degree in arm-trained athletes. Runners demonstrated a transfer of training effect in the performance of dynamic arm exercise, as demonstrated by their ability to achieve a higher peak work rate than controls, and showed a lower heart rate response to submaximal exercise than the wheelchair athletes and control subjects.

  2. Crew Exercise

    Science.gov (United States)

    Rafalik, Kerrie K.

    2017-01-01

    Johnson Space Center (JSC) provides research, engineering, development, integration, and testing of hardware and software technologies for exercise systems applications in support of human spaceflight. This includes sustaining the current suite of on-orbit exercise devices by reducing maintenance, addressing obsolescence, and increasing reliability through creative engineering solutions. Advanced exercise systems technology development efforts focus on the sustainment of crew's physical condition beyond Low Earth Orbit for extended mission durations with significantly reduced mass, volume, and power consumption when compared to the ISS.

  3. Ethical issues in exercise psychology.

    Science.gov (United States)

    Pauline, Jeffrey S; Pauline, Gina A; Johnson, Scott R; Gamble, Kelly M

    2006-01-01

    Exercise psychology encompasses the disciplines of psychiatry, clinical and counseling psychology, health promotion, and the movement sciences. This emerging field involves diverse mental health issues, theories, and general information related to physical activity and exercise. Numerous research investigations across the past 20 years have shown both physical and psychological benefits from physical activity and exercise. Exercise psychology offers many opportunities for growth while positively influencing the mental and physical health of individuals, communities, and society. However, the exercise psychology literature has not addressed ethical issues or dilemmas faced by mental health professionals providing exercise psychology services. This initial discussion of ethical issues in exercise psychology is an important step in continuing to move the field forward. Specifically, this article will address the emergence of exercise psychology and current health behaviors and offer an overview of ethics and ethical issues, education/training and professional competency, cultural and ethnic diversity, multiple-role relationships and conflicts of interest, dependency issues, confidentiality and recording keeping, and advertisement and self-promotion.

  4. Prevention: Exercise

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    Full Text Available ... Choices 10 Tips for a Healthy Back Smoking Weight Patient Safety Exercise Strengthening Strengthen Your Core! Stretching/ ... something providing resistance. It can be done with weights (hand-held or training machines) or using isometric ...

  5. Prevention: Exercise

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    Full Text Available ... 15 repetitions at a slow and controlled pace... Resistance Training Resistance training is exercise done against something providing resistance. It can be done with weights (hand-held ...

  6. Prevention: Exercise

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    Full Text Available ... Exercise Strength Training for the Elderly Other Back Pack Safety Pregnancy and Back Pain Preventing Osteoporosis Back ... in very slightly. Hold a ball directly in front of you. Keep your abdominal muscles tight and ...

  7. Prevention: Exercise

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    Full Text Available ... you should stop doing it. Transverse Core Strengthening This strengthens the muscles that cross from your ribs ... heavier balls, you will experience more benefit from this exercise... Sagittal Core Strengthening You can stretch and ...

  8. Compulsive Exercise

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    ... Exercise Safety Are Steroids Worth the Risk? Binge Eating Disorder Sports Supplements Female Athlete Triad Body Image and Self-Esteem What's the Right Weight for My Height? Eating Disorders Strength Training Contact Us Print Resources Send to ...

  9. Prevention: Exercise

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    Full Text Available ... following suggested exercises increases your back pain after five repetitions, or causes acute pain, you should stop ... 10 seconds working towards 30 seconds. Repeat 1-5 times or to fatigue... Prone Bridge/Plank Prop ...

  10. Prevention: Exercise

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    Full Text Available ... or causes acute pain, you should stop doing it. Transverse Core Strengthening This strengthens the muscles that ... training is exercise done against something providing resistance. It can be done with weights (hand-held or ...

  11. Prevention: Exercise

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    Full Text Available ... the Spine Definitions A-Z Spine Specialists Videos 9 for Spine Epidural Steroid Injections Exercise: The Backbone ... for 10 seconds working towards 30 seconds. Repeat 1-5 times or to fatigue... Prone Bridge/Plank ...

  12. Prevention: Exercise

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    Full Text Available ... 10 Tips for a Healthy Back Smoking Weight Patient Safety Exercise Strengthening Strengthen Your Core! Stretching/Flexibility ... Pain Preventing Osteoporosis Back Pain Basics Book RESOURCES Patient Information Feature Articles Patient Q&A Success Stories ...

  13. Prevention: Exercise

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    Full Text Available ... slow full movements. Repeat 10-15 times, to fatigue... Abdominal Exercise Lay on your back with both ... Return leg and extend other leg. Repeat to fatigue, about 10-15 repetitions at a slow and ...

  14. Prevention: Exercise

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  15. Prevention: Exercise

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    Full Text Available ... and Education Injection Treatments for Spinal Pain Epidural Steroid Injections Lumbar Zygapophysical (Facet) Joint Injections PREVENTION Lifestyle ... Z Spine Specialists Videos 9 for Spine Epidural Steroid Injections Exercise: The Backbone of Spine Treatment Spondylolisthesis ...

  16. Prevention: Exercise

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    Full Text Available ... Physical Therapy Postural Training Traction Watchful Waiting and Education Injection Treatments for Spinal Pain Epidural Steroid Injections ... martial arts all provide well-rounded core strengthening programs. Simple exercises can be done at home as ...

  17. Prevention: Exercise

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    Full Text Available ... legs to touch the wall, keeping hips and knees bent. Use your hips to push your body ... Abdominal Exercise Lay on your back with both knees bent. Draw abdominal wall in. Maintaining abdominal wall ...

  18. Compulsive Exercise

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    ... October 2013 More on this topic for: Parents Kids Teens Developing Your Child's Self-Esteem Obsessive-Compulsive Disorder Body Dysmorphic Disorder Your Child's Weight Kids and Exercise Encouraging a Healthy Body Image Eating ...

  19. Prevention: Exercise

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    Full Text Available ... Pain Other Scoliosis Back Pain and Emotional Distress Muscle Spasms Pinched Nerve Discitis Degenerative Conditions Bulge vs ... exercise focus on core strengthening, or building the muscles that provide support for your body. Pilates, yoga ...

  20. Prevention: Exercise

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    Full Text Available ... provide support for your body. Pilates, yoga and martial arts all provide well-rounded core strengthening programs. Simple ... repetitions at a slow and controlled pace... Resistance Training Resistance training is exercise done against something providing ...

  1. Basal and exercise-induced neuroendocrine activation in patients with heart failure and in normal subjects

    DEFF Research Database (Denmark)

    Kjaer, Andreas; Appel, Jon; Hildebrandt, Per

    2004-01-01

    : Twenty-three newly-diagnosed CHF patients and 18 age- and gender-matched healthy subjects were exercised at two workloads, which were calculated to correspond to 50 and 75% of each individual's heart rate response. RESULTS: In CHF patients, baseline levels of ANP, BNP, AVP, PRA and ET-1 were elevated...... compared to healthy subjects. Exercise induced an increase in ANP, A and NA in both CHF patients and in normal subjects, however BNP was only increased in CHF patients and not in normal subjects. CONCLUSION: When CHF patients exercise at the same relative and submaximal level as age-matched healthy...... subjects, the relative increases in ANP, A and NA were similar, however, BNP levels only increased in the CHF group....

  2. Growth Hormone Receptor Antagonist Treatment Reduces Exercise Performance in Young Males

    DEFF Research Database (Denmark)

    Goto, K.; Doessing, S.; Nielsen, R.H.

    2009-01-01

    in the treatment group compared with the placebo group (P V) over dotO(2max) did not change significantly in either group after the treatment period. Time to exhaustion at 90% of (V) over dotO(2max) was significantly shorter in the treatment group (P ... a maximal oxygen uptake ((V) over dotO(2max)) test and a prolonged exercise test, consisting of 60 min of submaximal cycling followed by exercise to fatigue at 90% of (V) over dotO(2max). Main Outcome Measures: (V) over dotO(2max) was measured before and after the treatment period. Hormonal and metabolic...... responses and time to exhaustion during prolonged exercise were determined. Results: Resting serum IGF-I concentration decreased by 20% in the GHR antagonist-treated group (P

  3. Cerebral Blood Flow Responses to Aquatic Treadmill Exercise.

    Science.gov (United States)

    Parfitt, Rhodri; Hensman, Marianne Y; Lucas, Samuel J E

    2017-07-01

    Aquatic treadmills are used as a rehabilitation method for conditions such as spinal cord injury, osteoarthritis, and stroke, and can facilitate an earlier return to exercise training for athletes. However, their effect on cerebral blood flow (CBF) responses has not been examined. We tested the hypothesis that aquatic treadmill exercise would augment CBF and lower HR compared with land-based treadmill exercise. Eleven participants completed incremental exercise (crossover design) starting from walking pace (4 km·h, immersed to iliac crest [aquatic], 6 km·h [land]) and increasing 1 km·h every 2 min up to 10 km·h for aquatic (maximum belt speed) or 12 km·h for land. After this, participants completed two 2-min bouts of exercise immersed to midthigh and midchest at constant submaximal speed (aquatic), or were ramped to exhaustion (land; increased gradient 2° every min). Middle cerebral artery blood flow velocity (MCAv) and HR were measured throughout, and the initial 10 min of each protocol and responses at each immersion level were compared. Compared with land-based treadmill, MCAvmean increased more from baseline for aquatic exercise (21% vs 12%, P aquatic walking compared with land-based moderate intensity running (~10 cm·s, P = 0.56). Greater water immersion lowered HR (139 vs 178 bpm for midchest vs midthigh), whereas MCAvmean remained constant (P = 0.37). Findings illustrate the potential for aquatic treadmill exercise to enhance exercise-induced elevations in CBF and thus optimize shear stress-mediated adaptation of the cerebrovasculature.

  4. Effects of a 6-month exercise program pilot study on walking economy, peak physiological characteristics, and walking performance in patients with peripheral arterial disease

    Directory of Open Access Journals (Sweden)

    Crowther RG

    2012-04-01

    Full Text Available Robert G Crowther1, Anthony S Leicht1, Warwick L Spinks1, Kunwarjit Sangla2, Frank Quigley2, Jonathan Golledge2,31Institute of Sport and Exercise Science, James Cook University, Townsville, Queensland, Australia; 2Townsville Hospital, Townsville, Queensland, Australia; 3The Vascular Biology Unit, James Cook University, Townsville, Queensland, AustraliaAbstract : The purpose of this study was to examine the effects of a 6-month exercise program on submaximal walking economy in individuals with peripheral arterial disease and intermittent claudication (PAD-IC. Participants (n = 16 were randomly allocated to either a control PAD-IC group (CPAD-IC, n = 6 which received standard medical therapy, or a treatment PAD-IC group (TPAD-IC; n = 10 which took part in a supervised exercise program. During a graded treadmill test, physiological responses, including oxygen consumption, were assessed to calculate walking economy during submaximal and maximal walking performance. Differences between groups at baseline and post-intervention were analyzed via Kruskal–Wallis tests. At baseline, CPAD-IC and TPAD-IC groups demonstrated similar walking performance and physiological responses. Postintervention, TPAD-IC patients demonstrated significantly lower oxygen consumption during the graded exercise test, and greater maximal walking performance compared to CPAD-IC. These preliminary results indicate that 6 months of regular exercise improves both submaximal walking economy and maximal walking performance, without significant changes in maximal walking economy. Enhanced walking economy may contribute to physiological efficiency, which in turn may improve walking performance as demonstrated by PAD-IC patients following regular exercise programs.Keywords: vascular disease, peripheral vascular disease, walking economy

  5. Now see this: a new vision of exercise imagery.

    Science.gov (United States)

    Munroe-Chandler, Krista J; Gammage, Kimberley L

    2005-10-01

    Recent exercise imagery findings suggest that past research in this field has been shortsighted and has severely curtailed progress in this important area. The authors provide a conceptual framework that focuses on how imagery may impact exercise behavior. This model expands our current knowledge of exercise imagery to suggest how it may function as an effective intervention to increase exercise behavior.

  6. Epilepsy and physical exercise.

    Science.gov (United States)

    Pimentel, José; Tojal, Raquel; Morgado, Joana

    2015-02-01

    Epilepsy is one of the commonest neurologic diseases and has always been associated with stigma. In the interest of safety, the activities of persons with epilepsy (PWE) are often restricted. In keeping with this, physical exercise has often been discouraged. The precise nature of a person's seizures (or whether seizures were provoked or unprovoked) may not have been considered. Although there has been a change in attitude over the last few decades, the exact role of exercise in inducing seizures or aggravating epilepsy still remains a matter of discussion among experts in the field. Based mainly on retrospective, but also on prospective, population and animal-based research, the hypothesis that physical exercise is prejudicial has been slowly replaced by the realization that physical exercise might actually be beneficial for PWE. The benefits are related to improvement of physical and mental health parameters and social integration and reduction in markers of stress, epileptiform activity and the number of seizures. Nowadays, the general consensus is that there should be no restrictions to the practice of physical exercise in people with controlled epilepsy, except for scuba diving, skydiving and other sports at heights. Whilst broader restrictions apply for patients with uncontrolled epilepsy, individual risk assessments taking into account the seizure types, frequency, patterns or triggers may allow PWE to enjoy a wide range of physical activities. Copyright © 2014 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  7. Central and Peripheral Fatigue During Resistance Exercise – A Critical Review

    Directory of Open Access Journals (Sweden)

    Zając Adam

    2015-12-01

    Full Text Available Resistance exercise is a popular form of conditioning for numerous sport disciplines, and recently different modes of strength training are being evaluated for health benefits. Resistance exercise differs significantly in nature, and several variables determine the direction and range of adaptive changes that occur in the muscular and skeletal system of the body. Some modes of resistance training can also be effective in stimulating the cardiovascular system. These variables include exercise selection (general, specific, single or multi joint, dynamic, explosive, type of resistance (free weights, variable resistance, isokinetics, order of exercise (upper and lower body or push and pull exercises, and most of all the training load which includes intensity expressed as % of 1RM, number of repetitions, number of sets and the rest interval between sets. Manipulating these variables allows for specific adaptive changes which may include gains in muscle mass, muscle strength or muscle endurance. It has been well established that during resistance exercise fatigue occurs, regardless of the volume and intensity of work applied. The peripheral mechanisms of fatigue have been studied and explained in more detail than those related to the CNS. This review is an attempt to bring together the latest knowledge regarding fatigue, both peripheral and central, during resistance exercise. The authors of this review concentrated on physiological and biochemical mechanisms underlying fatigue in exercises performed with maximal intensity, as well as those performed to exhaustion with numerous repetitions and submaximal load.

  8. Cardiopulmonary Exercise Testing in Patients with Heart Failure with Specific Comorbidities.

    Science.gov (United States)

    Piepoli, Massimo F; Corrà, Ugo; Agostoni, Piergiuseppe

    2017-07-01

    Exercise capacity is one of the most powerful predicting factors of life expectancy, both in patients with and those without cardiac disease. Cardiopulmonary exercise testing provides a global assessment of the integrative exercise responses involving the pulmonary, cardiovascular, hematopoietic, neuropsychological, and skeletal muscle systems, which are not adequately reflected through the measurement of individual organ system function. This relatively noninvasive, dynamic, physiologic overview allows the evaluation of both submaximal and peak exercise responses, providing the physician with relevant information for clinical decision-making. Chronic heart failure is a significant cause of worldwide mortality and morbidity, whose clinical picture is characterized by exercise intolerance and impaired quality of life. The purpose of this review is to provide an update of the role of cardiopulmonary exercise testing in patients with heart failure with specific comorbidities. Patients with heart failure frequently present concomitant clinical conditions, such as obesity, anemia, lung or kidney disease, diabetes mellitus, cancer, depression, and psychogenic disorders, which could affect length and quality of life, including everyday activities and exercise performance. Poor effort and malingering may be suspected when early discontinuation of the exercise test with irregular breathing occurs.

  9. Cardiovascular exercise in the U.S. space program: Past, present and future

    Science.gov (United States)

    Moore, Alan D.; Lee, Stuart M. C.; Stenger, Michael B.; Platts, Steven H.

    2010-04-01

    Exercise deconditioning during space flight may impact a crewmember's ability to perform strenuous or prolonged tasks during and after a spaceflight mission. In this paper, we review the cardiovascular exercise data from U.S. spaceflights from the Mercury Project through International Space Station (ISS) expeditions and potential implications upon current and future missions. During shorter spaceflights (exercise testing and maximum oxygen consumption (VO 2 max) are not changed. The submaximal exercise HR responses during longer duration flights are less consistent, and VO 2 max has not been measured. Skylab data demonstrated no change in the exercise HR response during flight which would be consistent with no change in VO 2 max; however, during ISS flight exercise HR is elevated early in the mission, but approaches preflight levels later during the missions, perhaps due to performance of exercise countermeasures. An elevated exercise HR is consistently observed after both short and long duration spaceflight, and crewmembers appear to recover at rates which are affected by the length of the mission.

  10. Emphysema on Thoracic CT and Exercise Ventilatory Inefficiency in Mild-to-Moderate COPD.

    Science.gov (United States)

    Jones, Joshua H; Zelt, Joel T; Hirai, Daniel M; Diniz, Camilla V; Zaza, Aida; O'Donnell, Denis E; Neder, J Alberto

    2017-04-01

    There is growing evidence that emphysema on thoracic computed tomography (CT) is associated with poor exercise tolerance in COPD patients with only mild-to-moderate airflow obstruction. We hypothesized that an excessive ventilatory response to exercise (ventilatory inefficiency) would underlie these abnormalities. In a prospective study, 19 patients (FEV1 = 82 ± 13%, 12 Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 1) and 26 controls underwent an incremental exercise test. Ventilatory inefficiency was assessed by the ventilation ([Formula: see text]E)/CO2 output ([Formula: see text]CO2) nadir. Pulmonary blood flow (PBF) in a submaximal test was calculated by inert gas rebreathing. Emphysema was quantified as % of attenuation areas below 950 HU. Patients typically presented with centrilobular emphysema (76.8 ± 10.1% of total emphysema) in the upper lobes (upper/total lung ratio = 0.82 ± 0.04). They had lower peak oxygen uptake ([Formula: see text]O2), higher [Formula: see text]E/[Formula: see text]CO2 nadir, and greater dyspnea scores than controls (p exercise (p exercise (r = -0.69) (p exercise ventilatory efficiency in mild-to-moderate COPD. Exercise ventilatory inefficiency links structure (emphysema) and function (DLCO) to a key clinical outcome (poor exercise tolerance) in COPD patients with only modest spirometric abnormalities.

  11. Physical efficiency and activity energy expenditure in term pregnancy females measured during cardiopulmonary exercise tests with a supine cycle ergometer.

    Science.gov (United States)

    Jędrzejko, Maciej; Nowosielski, Krzysztof; Poręba, Ryszard; Ulman-Włodarz, Izabela; Bobiński, Rafał

    2016-12-01

    To evaluate physical efficiency and activity energy expenditure (AEE) in term pregnancy females during cardiopulmonary exercise tests with a supine cycle ergometer. The study comprised 22 healthy full-term pregnancy women with uncomplicated pregnancies hospitalized in the Department of Gynecology and Obstetrics, Specialist Teaching Hospital in Tychy, Poland. All subjects underwent cardiopulmonary exercise tests (CPET) on a supine cycle ergometer. The 12-min, three-stage, progressive, symptom-limited submaximal test protocol (up to 80% HRmax) was used. Pulsometry was used to record HR on a beat-to-beat analysis and to calculate AEE. Respiratory responses were measured by ergospirometer and a computer system on a breath-by-breath basis at rest, during exercise and at restitution. In the studied population, VO2max was established at the level of 2.19 ± 0.33 L/min in ergospirometry and 2.04 ± 025 L/min in pulsometry. Physical efficiency calculated for sub-maximal exercise by use of the Davis equation was 30.52 ± 0.12%. AEE, based on VO2 in various phases of the CPET, was 0.47, 0.71 and 0.88 L/min for phases 25, 50 and 75 W. Based on ergospirometer readouts, AEE was 10.60, 16.11 and 20.94 kJ/min for phases 25, 50 and 75 W. Overall mean AEE (determined by pulsometry) was 10.59  kJ/min. CPET testing did not have any negative effect upon the health or life of the neonates involved in the study. Submaximal CPET up to 80% HRmax with a supine cycle ergometer is a safe and precise method for assessing work efficiency in term pregnancy women.

  12. Exercise conditioning and cardiopulmonary fitness in cystic fibrosis. The effects of a three-month supervised running program.

    Science.gov (United States)

    Orenstein, D M; Franklin, B A; Doershuk, C F; Hellerstein, H K; Germann, K J; Horowitz, J G; Stern, R C

    1981-10-01

    Exercise intolerance is common in cystic fibrosis (CF). We examined the effects of a supervised three-month running program on exercise tolerance, pulmonary function, cardiorespiratory fitness (peak oxygen consumption), and respiratory muscle endurance in CF patients. We studied 31 patients, 21 exercise and ten control, aged 10 to 30 years, with pulmonary involvement ranging from mild to severe. The exercise and control groups were not significantly different with respect to age, sex, pulmonary function, exercise tolerance, or cardiorespiratory fitness. After three months of physical conditioning, the exercise group had significantly increased exercise tolerance and peak oxygen consumption and significantly lower heart rates for submaximal work loads, while the nonexercising (control) group was unchanged in all these variables. The FEV1 decreased significantly in the control group. There were no other significant changes in pulmonary function in either the control or exercise group. Respiratory muscle endurance increased significantly in the exercise patients, and did not change in the control patients. There were no adverse effects of the program. The data suggest that a supervised running program can increase CF patients' exercise tolerance and cardiorespiratory fitness, perhaps in part by increasing respiratory muscle tolerance. The effects of a much longer program deserve study.

  13. A Multivariable Index for Grading Exercise Gas Exchange Severity in Patients with Pulmonary Arterial Hypertension and Heart Failure

    Directory of Open Access Journals (Sweden)

    Chul-Ho Kim

    2012-01-01

    Full Text Available Patients with pulmonary arterial hypertension (PAH and heart failure (HF display many abnormalities in respiratory gas exchange. These abnormalities are accentuated with exercise and track with disease severity. However, use of gas exchange measures in day-to-day clinical practice is limited by several issues, including the large number of variables available and difficulty in data interpretation. Moreover, maximal exercise testing has limitations in clinical populations due to their complexity, patient anxiety and variability in protocols and cost. Therefore, a multivariable gas exchange index (MVI that integrates key gas exchange variables obtained during submaximal exercise into a severity score that ranges from normal to severe-very-severe is proposed. To demonstrate the usefulness of this index, we applied this to 2 groups (PAH, n=42 and HF, n=47 as well as to age matched healthy controls (n=25. We demonstrate that this score tracks WHO classification and right ventricular systolic pressure in PAH (r=0.53 and 0.73, P≤0.01 and NYHA and cardiac index in HF (r=0.49 and 0.74, P≤0.01. This index demonstrates a stronger relationship than any single gas exchange variable alone. In conclusion, MVI obtained from light, submaximal exercise gas exchange is a useful approach to simplify data interpretation in PAH and HF populations.

  14. Rac1 and AMPK account for the majority of muscle glucose uptake stimulated by ex vivo contraction but not in vivo exercise

    DEFF Research Database (Denmark)

    Sylow, Lykke; Møller, Lisbeth Liliendal Valbjørn; Kleinert, Maximilian

    2017-01-01

    by Rac1 mKO with no additive effect of α2KD. It is concluded that Rac1 and α2AMPK together account for almost the entire ex vivo contraction-response in muscle glucose transport, while only Rac1, but not α2AMPK, regulates muscle glucose uptake during submaximal exercise in vivo....... but whether those two signaling pathways jointly account for the entire signal to glucose transport is unknown. We therefore studied the ability of contraction and exercise to stimulate glucose transport in isolated muscles with AMPK loss-of-function combined with either pharmacological inhibition or genetic...

  15. Modulation of blood pressure response to exercise by physical activity and relationship with resting blood pressure during pregnancy.

    Science.gov (United States)

    Bisson, Michèle; Rhéaume, Caroline; Bujold, Emmanuel; Tremblay, Angelo; Marc, Isabelle

    2014-07-01

    To determine whether physical activity and blood pressure (BP) response to exercise in early pregnancy are related to resting BP at the end of pregnancy. Understanding physiological BP responses to exercise during pregnancy will help in improving BP profile and guiding exercise recommendations in pregnant women. Maternal physical activity, cardiorespiratory fitness (VO2peak) and BP (systolic and diastolic) at rest and during exercise (submaximal and relative response) were assessed at 16 weeks of gestation in 61 normotensive pregnant women. BP at 36 weeks of gestation and obstetrical outcomes were collected from maternal charts. Related to resting DBP at 16 weeks (r =  -0.28, P = 0.028), total energy expenditure spend at any physical activity in early pregnancy was also associated with resting SBP at 36 weeks (r =  -0.27, P = 0.038). On the contrary, although related to VO2peak (r =  -0.57, P exercise (r =  -0.29, P = 0.024), the relative SBP response to exercise at 16 weeks was not associated with resting BP at 36 weeks. Strongly associated with resting BP at 16 weeks and also with total energy expenditure, submaximal BP response to exercise at 16 weeks was related to resting SBP and DBP at 36 weeks (r = 0.41, P = 0.001 and r = 0.26, P = 0.051, respectively). In normotensive women, physical activity performed in early pregnancy appears to slightly modulate resting BP in early and late pregnancy. However, further investigations are needed to determine which physical activity-related parameter in response to exercise best predicts BP variations during pregnancy.

  16. Long-term exercise training with constant energy intake. 1: Effect on body composition and selected metabolic variables.

    Science.gov (United States)

    Bouchard, C; Tremblay, A; Nadeau, A; Dussault, J; Després, J P; Theriault, G; Lupien, P J; Serresse, O; Boulay, M R; Fournier, G

    1990-01-01

    The effects of long-term negative energy balance generated by exercise while maintaining a constant energy intake were studied in five healthy young males (25 +/- 3 years; mean +/- s.d.). After 2 weeks of monitoring to determine habitual energy intake, they were subjected to a 100-day experimental period during which they exercised on a cycle ergometer, 6 days a week, twice a day at 55 per cent of VO2 max. The daily energy deficit was 4.2 MJ for a total of 353 MJ for the duration of the treatment. Body weight decreased from 86.7 to 78.7 kg (P less than 0.001). More than 80 per cent of the weight loss was accounted for by the reductions in fat mass. Fat-free mass did not change significantly. The data suggest that subcutaneous fat was lost about evenly from the trunk and from the limbs as estimated from skinfolds. Cardiorespiratory and metabolic responses to submaximal work loads indicate that the low intensity exercise regimen was capable of inducing some of the known adaptations of exercise training such as a decrease in plasma insulin and norepinephrine concentrations during exercise, reductions in heart rate, pulmonary ventilation and blood lactate concentration at a given exercise intensity, and an increase in skeletal muscle oxidative capacity. The energy cost of sitting and standing was not decreased in spite of the loss in body mass. However, the energy cost of submaximal cycling and walking exercises was reduced considerably. These results clearly demonstrate that it is quite possible to lose fat while preserving fat-free mass through regular prolonged exercise of moderate intensity if energy intake is kept constant at baseline level. They also emphasize the importance of the individual differences in response to negative energy balance.

  17. Evaluation of Maximal Oxygen Uptake and Submaximal Estimates of VO2max Before, During, and After Long Duration International Space Station Missions

    Science.gov (United States)

    2008-01-01

    Evaluation of Maximal Oxygen Uptake and Submaximal Estimates of VO2max Before, During, and After Long Duration International Space Station Missions (VO2max) will document changes in maximum oxygen uptake for crewmembers onboard the International Space Station (ISS) on long-duration missions, greater than 90 days. This investigation will establish the characteristics of VO2max during flight and assess the validity of the current methods of tracking aerobic capacity change during and following the ISS missions.

  18. Kinetics of left ventricular strains and torsion during incremental exercise in healthy subjects: the key role of torsional mechanics for systolic-diastolic coupling.

    Science.gov (United States)

    Doucende, Grégory; Schuster, Iris; Rupp, Thomas; Startun, Aliona; Dauzat, Michel; Obert, Philippe; Nottin, Stéphane

    2010-09-01

    The dynamics of systolic and diastolic strains and torsional mechanics of the left ventricle (LV) and their relation to diastolic filling never have been evaluated at various exercise intensities. Speckle tracking echocardiography was performed in 20 healthy sedentary subjects at rest and during a progressive submaximal exercise test at 20%, 30%, and 40% of maximal aerobic power. LV twist increased progressively with exercise intensity (10.5 ± 3.2 to 15.8 ± 4.5°; Pmechanical events were unchanged during effort. Untwisting was driven mainly by apical rotation and determined mitral opening and isovolumic relaxation time (R=0.47 and 0.61, respectively; Pmechanics during incremental exercise in healthy subjects, underlining the key role of torsional mechanics. It might be useful to better understand the mechanisms of diastolic dysfunction and exercise intolerance in various pathological conditions.

  19. Human muscle net K(+) release during exercise is unaffected by elevated anaerobic metabolism, but reduced after prolonged acclimatization to 4,100 m.

    Science.gov (United States)

    Nordsborg, Nikolai B; Calbet, José A L; Sander, Mikael; van Hall, Gerrit; Juel, Carsten; Saltin, Bengt; Lundby, Carsten

    2010-07-01

    It was investigated whether skeletal muscle K(+) release is linked to the degree of anaerobic energy production. Six subjects performed an incremental bicycle exercise test in normoxic and hypoxic conditions prior to and after 2 and 8 wk of acclimatization to 4,100 m. The highest workload completed by all subjects in all trials was 260 W. With acute hypoxic exposure prior to acclimatization, venous plasma [K(+)] was lower (P exercise intensity, leg net K(+) release was unaffected by hypoxic exposure independent of acclimatization. After 8 wk of acclimatization, no difference existed in venous plasma [K(+)] between the normoxic and hypoxic trial, either at submaximal intensities or at exhaustion (360 +/- 14 W vs. 313 +/- 8 W; P exercise intensity, leg net K(+) release was less (P exercise relative to rest was less (P anaerobic energy production and that acclimatization reduces leg net K(+) release during exercise.

  20. Post-exercise recovery of contractile function and endurance in humans and mice is accelerated by heating and slowed by cooling skeletal muscle

    DEFF Research Database (Denmark)

    Cheng, Arthur J; Willis, Sarah J; Zinner, Christoph

    2017-01-01

    recovery from fatigue-induced by endurance exercise is impaired by cooling and improved by heating, due to changes in glycogen resynthesis rate. ABSTRACT: Manipulation of muscle temperature is believed to improve post-exercise recovery, with cooling being especially popular among athletes. However......KEY POINTS: We investigated whether intramuscular temperature affects the acute recovery of exercise performance following fatigue-induced by endurance exercise. Mean power output was better preserved during an all-out arm-cycling exercise following a 2 h recovery period in which the upper arms...... muscle fibres where we found that recovery of submaximal force and restoration of fatigue resistance was worsened by cooling (16-26°C) and improved by heating (36°C). Isolated whole mouse muscle experiments confirmed that cooling impaired muscle glycogen resynthesis. We conclude that skeletal muscle...

  1. Biochemical characterization of exercise-trained porcine myocardium.

    Science.gov (United States)

    Laughlin, M H; Hale, C C; Novela, L; Gute, D; Hamilton, N; Ianuzzo, C D

    1991-07-01

    The purpose of this study was to determine whether cardiac biochemical adaptations are induced by chronic exercise training (ET) of miniature swine. Female Yucatan miniature swine were trained on a treadmill or were cage confined (C) for 16-22 wk. After training, the ET pigs had increased exercise tolerance, lower heart rates during exercise at submaximal intensities, moderate cardiac hypertrophy, increased coronary blood flow capacity, and increased oxidative capacity of skeletal muscle. Myosin from both the C and ET hearts was 100% of the V3 isozyme, and there were no differences between the myosin adenosine triphosphatase (ATPase) or myofibrillar ATPase activities of C and ET hearts. Also, the sarcoplasmic reticulum Ca(2+)-ATPase activity and Na(+)-Ca2+ exchange activity of sarcolemmal vesicles were the same in cardiac muscle of C and ET hearts. Finally, the glycolytic and oxidative capacity of ET cardiac muscle was not different from control, since phosphofructokinase, citrate synthase, and 3-hydroxyacyl-CoA dehydrogenase activities were the same in cardiac tissue from ET and C pigs. We conclude that endurance exercise training does not provide sufficient stress on the heart of a large mammal to induce changes in any of the three major cardiac biochemical systems of the porcine myocardium: the contractile system, the Ca2+ regulatory systems, or the metabolic system.

  2. Endurance and fatigue characteristics in the neck muscles during sub-maximal isometric test in patients with cervical radiculopathy.

    Science.gov (United States)

    Halvorsen, Marie; Abbott, Allan; Peolsson, Anneli; Dedering, Åsa

    2014-03-01

    The aim of the study was to compare myoelectric manifestation in neck muscle endurance and fatigue characteristics during sub-maximal isometric endurance test in patients with cervical radiculopathy and asymptomatic subjects. An additional aim was to explore associations between primary neck muscle endurance, myoelectric fatigability, and self-rated levels of fatigue, pain and subjective health measurements in patients with cervical radiculopathy. Muscle fatigue in the ventral and dorsal neck muscles was assessed in patients with cervical radiculopathy and in an asymptomatic group during an isometric neck muscle endurance test in prone and supine. 46 patients and 34 asymptomatic subjects participated. Surface electromyography signals were recorded from the sternocleidomastoid, cervical paraspinal muscles and upper and middle trapezius bilaterally during the endurance test. Subjective health measurements were assessed with questionnaires. The results showed altered neck muscle endurance in several of the muscles investigated with greater negative median frequency slope, greater variability, side imbalance, lower endurance time and higher experience of fatigue among the cervical radiculopathy patients compared with healthy subjects. Endurance times were significantly lower in both prone and in supine positions between the patients compared to asymptomatic subjects. During the neck muscle endurance test, fatigues in the upper trapezius muscles during the prone test and in the sternocleidomastoid muscles during the supine test were of more importance than self-perceived pain, fatigue, disability and kinesiophobia in predicting neck muscle endurance (NME). NME testing in the primary neck muscles seems to be an important factor to take into consideration in rehabilitation.

  3. The cardiovascular system after exercise.

    Science.gov (United States)

    Romero, Steven A; Minson, Christopher T; Halliwill, John R

    2017-04-01

    Recovery from exercise refers to the time period between the end of a bout of exercise and the subsequent return to a resting or recovered state. It also refers to specific physiological processes or states occurring after exercise that are distinct from the physiology of either the exercising or the resting states. In this context, recovery of the cardiovascular system after exercise occurs across a period of minutes to hours, during which many characteristics of the system, even how it is controlled, change over time. Some of these changes may be necessary for long-term adaptation to exercise training, yet some can lead to cardiovascular instability during recovery. Furthermore, some of these changes may provide insight into when the cardiovascular system has recovered from prior training and is physiologically ready for additional training stress. This review focuses on the most consistently observed hemodynamic adjustments and the underlying causes that drive cardiovascular recovery and will highlight how they differ following resistance and aerobic exercise. Primary emphasis will be placed on the hypotensive effect of aerobic and resistance exercise and associated mechanisms that have clinical relevance, but if left unchecked, can progress to symptomatic hypotension and syncope. Finally, we focus on the practical application of this information to strategies to maximize the benefits of cardiovascular recovery, or minimize the vulnerabilities of this state. We will explore appropriate field measures, and discuss to what extent these can guide an athlete's training. Copyright © 2017 the American Physiological Society.

  4. Mesenteric, coeliac and splanchnic blood flow in humans during exercise

    DEFF Research Database (Denmark)

    Perko, M J; Nielsen, H B; Skak, C

    1998-01-01

    1. Exercise reduces splanchnic blood flow, but the mesenteric contribution to this response is uncertain. 2. In nineteen humans, superior mesenteric and coeliac artery flows were determined by duplex ultrasonography during fasting and postprandial submaximal cycling and compared with the splanchnic...... blood flow as assessed by the Indocyanine Green dye-elimination technique. 3. Cycling increased arterial pressure, heart rate and cardiac output, while it reduced total vascular resistance. These responses were not altered in the postprandial state. During fasting, cycling increased mesenteric, coeliac...... the coeliac circulation was not influenced. Postprandial cycling did not influence the mesenteric resistance significantly, but its blood flow decreased by 22 % (0.46 +/- 0.28 l min-1). Coeliac and splanchnic resistance increased by 150 and 63 %, respectively, and the corresponding regional blood flow...

  5. Topological fields

    CERN Document Server

    Warner, S

    1989-01-01

    Aimed at those acquainted with basic point-set topology and algebra, this text goes up to the frontiers of current research in topological fields (more precisely, topological rings that algebraically are fields).The reader is given enough background to tackle the current literature without undue additional preparation. Many results not in the text (and many illustrations by example of theorems in the text) are included among the exercises. Sufficient hints for the solution of the exercises are offered so that solving them does not become a major research effort for the reader. A comprehensive bibliography completes the volume.

  6. Determinants of exercise blood pressure response in normotensive and hypertensive women: role of cardiorespiratory fitness.

    Science.gov (United States)

    Kokkinos, Peter F; Andreas, Pittaras E; Coutoulakis, Emmanuel; Colleran, John A; Narayan, Puneet; Dotson, Charles O; Choucair, Wassim; Farmer, Colleen; Fernhall, Bo

    2002-01-01

    Exaggerated blood pressure (BP) response during physical exertion is associated with increased risk for cardiovascular events. Furthermore, it may be the predisposing factor for myocardial infarction triggered by physical exertion. The authors have shown that systolic BP achieved after 6 minutes of exercise is the strongest predictor of left ventricular hypertrophy. Furthermore, a 37 mm Hg increase in systolic BP above resting BP at 6 minutes of exercise was the threshold for left ventricular hypertrophy. The purpose of this study was to determine predictors of exercise BP response in normotensive and hypertensive women. An exercise tolerance test (Bruce) was performed by 1411 normotensive (resting BP or = 140/90 mm Hg) women. These women were faculty, students, and staff at the University of Maryland, College Park, Maryland, and the George Washington University Medical Center, as well as patients undergoing a routine exercise tolerance test at West Coast Cardiology, Pinellas Park, Florida. Two fitness categories (low-fit and high-fit) were established on the basis of treadmill time to exhaustion adjusted for age. Significant associations were observed among the 6-minute exercise BP and age, body mass index, resting systolic and diastolic BP, heart rate, and exercise time to exhaustion. In a stepwise multiple-regression analysis, the determinants of BP after 6 minutes of exercise were resting systolic BP and treadmill time to exhaustion (R2 = 0.36) for normotensive women and treadmill time to exhaustion and resting systolic BP (R2 = 0.30) for hypertensive women. When fitness categories were contrasted, low-fit women in both the normotensive and hypertensive categories had higher BP and rate-pressure product after 6 minutes of exercise than the high-fit women (P fitness are determinants of a submaximal exercise BP response for both hypertensive and normotensive women. Low cardiorespiratory fitness is associated with a higher BP response during submaximal exercise

  7. Anaerobic energy production and O2 deficit-debt relationship during exhaustive exercise in humans

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Gollnick, PD; Graham, T

    1990-01-01

    1. Eight subjects performed one-legged, dynamic, knee-extensor exercise, first at 10 W followed by 10 min rest, then at an intense, exhaustive exercise load (65 W) lasting 3.2 min. After 60 min recovery, exercise was performed for 8-10 min each at 20, 30, 40 and 50 W. Measurements of pulmonary...... before and immediately after the intense exercise, and at 3, 10 and 60 min into recovery. 2. Individual linear relations (r = 0.95-1.00) between the power outputs for submaximal exercise and oxygen uptakes (leg and pulmonary) were used to estimate the energy demand during intense exercise. Pulmonary......, respectively. 3. During the intense exercise, muscle [ATP] decreased by 30% and [CP] by 60% from resting concentrations of 6.2 and 22.4 mmol (kg wet wt)-1, respectively, and [IMP] increased to 1.1 mmol (kg wet wt)-1. Muscle [lactate] increased from 2 to 28.1 mmol (kg wet wt)-1, and the concomitant net lactate...

  8. Exercise and Bone Health

    Science.gov (United States)

    ... are weightbearing exercise and strength-training exercise. Weightbearing Exercise © Thinkstock, 2012 Weightbearing describes any activity you do ... that would be best for them. Strength-Training Exercise © Thinkstock, 2012 During strength-training activities, resistance is ...

  9. Exercise-Induced Bronchoconstriction

    Science.gov (United States)

    ... Conditions & Treatments ▸ Conditions Dictionary ▸ Exercise-Induced Bronchoconstriction Share | Exercise-Induced Bronchoconstriction (EIB) « Back to A to Z Listing Exercise-Induced Bronchoconstriction, (EIB), often known as exercise-induced ...

  10. Exercise at Home

    Science.gov (United States)

    ... Home Health Insights Exercise & Weight Exercise at Home Exercise at Home Make an Appointment Ask a Question ... with the movement and contact your provider. Posture Exercises Better posture means better breathing and movement. Axial ...

  11. DIFFERENT CIRCULATING BRAIN-DERIVED NEUROTROPHIC FACTOR RESPONSES TO ACUTE EXERCISE BETWEEN PHYSICALLY ACTIVE AND SEDENTARY SUBJECTS

    Directory of Open Access Journals (Sweden)

    Yu Nofuji

    2012-03-01

    Full Text Available Although circulating brain-derived neurotrophic factor (BDNF level is affected by both acute and chronic physical activity, the interaction of acute and chronic physical activity was still unclear. In this study, we compared the serum and plasma BDNF responses to maximal and submaximal acute exercises between physically active and sedentary subjects. Eight active and 8 sedentary female subjects participated in the present study. Both groups performed 3 exercise tests with different intensities, i.e. 100% (maximal, 60% (moderate and 40% (low of their peak oxygen uptake. In each exercise test, blood samples were taken at the baseline and immediately, 30 and 60 min after the test. The serum BDNF concentration was found to significantly increase immediately after maximal and moderate exercise tests in both groups. In maximal exercise test, the pattern of change in the serum BDNF concentration was different between the groups. While the serum BDNF level for the sedentary group returned to the baseline level during the recovery phase, the BDNF levels for the active group decreased below the baseline level after the maximal exercise test. No group differences were observed in the pattern of plasma BDNF change for all exercise tests. These findings suggest that regular exercise facilitates the utilization of circulating BDNF during and/or after acute exercise with maximal intensity

  12. Exercise gaming

    DEFF Research Database (Denmark)

    Smaerup, M.; Grönvall, E.; Larsen, S. B.

    2017-01-01

    with computer-assisted home training. The interviews evolved around themes, such as the elderly participants' self-efficacy, motivation and acceptance of the technology. Results Age was not an excuse for the modest exercise compliance. The participants were basically self-efficient and accepted the technology...

  13. Eccentric exercise

    DEFF Research Database (Denmark)

    Kjaer, Michael; Heinemeier, Katja Maria

    2014-01-01

    Eccentric exercise can influence tendon mechanical properties and matrix protein synthesis. mRNA for collagen and regulatory factors thereof are upregulated in animal tendons, independent of muscular contraction type, supporting the view that tendon, compared with skeletal muscle, is less sensitive...

  14. Exercise Habit

    Science.gov (United States)

    ... are injured.Make exercise fun.Read, listen to music, or watch TV while you ride a stationary bicycle, for example. Find fun activities, like taking a walk through the zoo. Go dancing. Learn how to play a sport you enjoy.Track your activity. Keep track of ...

  15. Prevention: Exercise

    Medline Plus

    Full Text Available ... use progressively heavier balls, you will experience more benefit from this exercise... Sagittal Core Strengthening You can ... can be done with weights (hand-held or training machines) or using isometric ... program that matches your abilities. Neck Press This is ...

  16. Evacuation exercise

    CERN Multimedia

    AUTHOR|(CDS)2094367

    2017-01-01

    In the event of an emergency, it is important that staff and visitors are evacuated safely and efficiently. Hence CERN organises regularly emergency response and evacuation exercise (also known as an ‘evacuation drill’) in different buildings across the sites.

  17. Prevention: Exercise

    Medline Plus

    Full Text Available ... 10 Tips for a Healthy Back Smoking Weight Patient Safety Exercise Strengthening Strengthen Your Core! Stretching/Flexibility Aerobic ... Strength Training for the Elderly Other Back Pack Safety Pregnancy and Back ... Patient Information Feature Articles Patient Q&A Success Stories ...

  18. Prevention: Exercise

    Medline Plus

    Full Text Available ... building the muscles that provide support for your body. Pilates, yoga and martial arts all provide well-rounded core strengthening programs. Simple exercises can be done at home as well. Some specific core strengthening ... your hips to push your body back to a standing position, then extend your ...

  19. The Impact of Central and Peripheral Cyclooxygenase Enzyme Inhibition on Exercise-Induced Elevations in Core Body Temperature.

    Science.gov (United States)

    Veltmeijer, Matthijs T W; Veeneman, Dineke; Bongers, Coen C C W; Netea, Mihai G; van der Meer, Jos W; Eijsvogels, Thijs M H; Hopman, Maria T E

    2017-05-01

    Exercise increases core body temperature (TC) due to metabolic heat production. However, the exercise-induced release of inflammatory cytokines including interleukin-6 (IL-6) may also contribute to the rise in TC by increasing the hypothalamic temperature set point. This study investigated whether the exercise-induced increase in TC is partly caused by an altered hypothalamic temperature set point. Fifteen healthy, active men age 36 ± 14 y were recruited. Subjects performed submaximal treadmill exercise in 3 randomized test conditions: (1) 400 mg ibuprofen and 1000 mg acetaminophen (IBU/APAP), (2) 1000 mg acetaminophen (APAP), and (3) a control condition (CTRL). Acetaminophen and ibuprofen were used to block the effect of IL-6 at a central and peripheral level, respectively. TC, skin temperature, and heart rate were measured continuously during the submaximal exercise tests. Baseline values of TC, skin temperature, and heart rate did not differ across conditions. Serum IL-6 concentrations increased in all 3 conditions. A significantly lower peak TC was observed in IBU/APAP (38.8°C ± 0.4°C) vs CTRL (39.2°C ± 0.5°C, P = .02) but not in APAP (38.9°C ± 0.4°C) vs CTRL. Similarly, a lower ΔTC was observed in IBU/APAP (1.7°C ± 0.3°C) vs CTRL (2.0°C ± 0.5°C, P skin temperature and heart-rate responses across conditions. The combined administration of acetaminophen and ibuprofen resulted in an attenuated increase in TC during exercise compared with a CTRL. This observation suggests that a prostaglandin-E2-induced elevated hypothalamic temperature set point may contribute to the exercise-induced rise in TC.

  20. Work capacity, exercise responses and body composition of professional pilots in relation to age.

    Science.gov (United States)

    Loeppky, J A; Luft, U C

    1989-11-01

    Body composition and submaximal and maximal cardiorespiratory responses during a progressive upright bicycle ergometer test were measured in 410 professional male pilots, aged 20 to 68 years, and divided into four groups (30, 39, 49, and 59 years). Fat-free weight by hydrostatic weighing was not significantly different between groups and fat increased linearly with age, while height was lower and weight levelled off in the oldest group. Aerobic work capacity (VO2max) fell at a rate of 0.25 ml.min-1.kg-1 per year in this unique population of healthy, but generally sedentary men. A subgroup of 10 pilots, tested annually from age 31 to 47, demonstrated a reversal of the age-related decline in VO2max. This was attributable to regular physical activity, short of athletic training, and changes in personal health habits stimulated by self-assessment available from the repeated tests incorporated into the medical prevention program. These data considered in relation to more recent reports of stroke volume during similar maximal exercise protocols suggest that VO2max is limited during aging by a reduction in tissue diffusing capacity or increased maldistribution of perfusion in relation to O2 uptake in muscle and this can be partially prevented by training. Reference standards for heart rate, blood pressure and ventilation during submaximal and maximal exercise levels are presented in relation to energy requirements and work intensity at various ages.

  1. High-frequency submaximal stimulation over muscle evokes centrally generated forces in human upper limb skeletal muscles.

    Science.gov (United States)

    Blouin, Jean-Sébastien; Walsh, Lee D; Nickolls, Peter; Gandevia, Simon C

    2009-02-01

    Control of posture and movement requires control of the output from motoneurons. Motoneurons of human lower limb muscles exhibit sustained, submaximal activity to high-frequency electrical trains, which has been hypothesized to be partly triggered by monosynaptic Ia afferents. The possibility to trigger such behavior in upper limb motoneurons and the potential unique role of Ia afferents to trigger such behavior remain unclear. Subjects (n = 9) received high-frequency trains of electrical stimuli over biceps brachii and flexor pollicis longus (FPL). We chose to study the FPL muscle because it has weak monosynaptic Ia afferent connectivity and it is involved in fine motor control of the thumb. Two types of stimulus trains (100-Hz bursts and triangular ramps) were tested at five intensities below painful levels. All subjects exhibited enhanced torque in biceps and FPL muscles after both types of high-frequency train. Torques also persisted after stimulation, particularly for the highest stimulus intensity. To separate the evoked torques that resulted from a peripheral mechanism (e.g., muscle potentiation) and that which resulted from a central origin, we studied FPL responses to high-frequency trains after complete combined nerve blocks of the median and radial nerves (n = 2). During the blocks, high-frequency trains over the FPL did not yield torque enhancements or persisting torques. These results suggest that enhanced contractions of central origin can be elicited in motoneurons innervating the upper limb, despite weak monosynaptic Ia connections for FPL. Their presence in a recently evolved human muscle (FPL) indicates that these enhanced contractions may have a broad role in controlling tonic postural outputs of hand muscles and that they may be available even for fine motor activities involving the thumb.

  2. Muscle coordination, activation and kinematics of world-class and elite breaststroke swimmers during submaximal and maximal efforts.

    Science.gov (United States)

    Olstad, Bjørn Harald; Vaz, João Rocha; Zinner, Christoph; Cabri, Jan M H; Kjendlie, Per-Ludvik

    2017-06-01

    The aims of this study were to describe muscular activation patterns and kinematic variables during the complete stroke cycle (SC) and the different phases of breaststroke swimming at submaximal and maximal efforts. Surface electromyography (sEMG) was collected from eight muscles in nine elite swimmers; five females (age 20.3 ± 5.4 years; Fédération Internationale de Natation [FINA] points 815 ± 160) and four males (27.7 ± 7.1 years; FINA points 879 ± 151). Underwater cameras were used for 3D kinematic analysis with automatic motion tracking. The participants swam 25 m of breaststroke at 60%, 80% and 100% effort and each SC was divided into three phases: knee extension, knee extended and knee flexion. With increasing effort, the swimmers decreased their SC distance and increased their velocity and stroke rate. A decrease during the different phases was found for duration during knee extended and knee flexion, distance during knee extended and knee angle at the beginning of knee extension with increasing effort. Velocity increased for all phases. The mean activation pattern remained similar across the different effort levels, but the muscles showed longer activation periods relative to the SC and increased integrated sEMG (except trapezius) with increasing effort. The muscle activation patterns, muscular participation and kinematics assessed in this study with elite breaststroke swimmers contribute to a better understanding of the stroke and what occurs at different effort levels. This could be used as a reference for optimising breaststroke training to improve performance.

  3. [The effect of exercise on the pharmacokinetics of acetaminophen and acetylsalicylic acid].

    Science.gov (United States)

    Sawrymowicz, M

    1997-01-01

    The influence of exercise on the pharmacokinetics of drugs is not sufficiently apparent. Therefore the purpose of my study was to evaluate the influence of standardized exercise on pharmacokinetics of acetaminophen and acetylsalicylic acid (ASA) and also to establish whether moderate (submaximal) exercise demands modification involving the doses of these drugs. That was studied in 20 healthy young (ranging in age 22-42 years) male subjects receiving acetaminophen or ASA, 1 g orally. All subjects were non-smokers who abstained from using caffeine and alcohol 2 weeks before and in the period of study, which consisted of two parts: resting trials and exercise trials. Exercise trials: treadmill walking--3 mph (4.8 km/h), 20 minutes per half an hour for 3 hours (50% VO2max). On the rest day volunteers stayed in the supine or sitting position for the same period. Blood samples were collected from a forearm (antecubital) vein through an indwelling cannula. Acetaminophen and ASA plasma concentrations were determined by FPIA. The plasma level-time curves were fitted according to one compartment open pharmacokinetic model. Plasma concentrations measured (7 days) before and after the physical exercise, did not demonstrate statistically significant differences (Fig. 1, 2). The results of this study indicate that the pharmacokinetics of single doses of acetaminophen and ASA are independent of submaximal physical exercise. There were no significant differences between the rest and the exercise day in the pharmacokinetic parameters of acetaminophen and ASA (Fig. 3). Since both drugs belong to the group whose elimination is not due to the liver flow, it is not surprising that its total body clearance, and its half-life of elimination were unaffected by physical exercise. The minor changes in haematocrit, plasma protein, free fatty acids, levels which were reported are probably not sufficient to modify the disposition of these drugs. Therefore, there is no need for dose adjustment

  4. How Hinge Positioning in Cross-Country Ski Bindings Affect Exercise Efficiency, Cycle Characteristics and Muscle Coordination during Submaximal Roller Skiing.

    Directory of Open Access Journals (Sweden)

    Conor M Bolger

    Full Text Available The purposes of the current study were to 1 test if the hinge position in the binding of skating skis has an effect on gross efficiency or cycle characteristics and 2 investigate whether hinge positioning affects synergistic components of the muscle activation in six lower leg muscles. Eleven male skiers performed three 4-min sessions at moderate intensity while cross-country ski-skating and using a klapskate binding. Three different positions were tested for the binding's hinge, ranging from the front of the first distal phalange to the metatarsal-phalangeal joint. Gross efficiency and cycle characteristics were determined, and the electromyographic (EMG signals of six lower limb muscles were collected. EMG signals were wavelet transformed, normalized, joined into a multi-dimensional vector, and submitted to a principle component analysis (PCA. Our results did not reveal any changes to gross efficiency or cycle characteristics when altering the hinge position. However, our EMG analysis found small but significant effects of hinge positioning on muscle coordinative patterns (P < 0.05. The changed patterns in muscle activation are in alignment with previously described mechanisms that explain the effects of hinge positioning in speed-skating klapskates. Finally, the within-subject results of the EMG analysis suggested that in addition to the between-subject effects, further forms of muscle coordination patterns appear to be employed by some, but not all participants.

  5. Effects of Ramadan intermittent fasting on North African children's heart rate and oxy-haemoglobin saturation at rest and during sub-maximal exercise.

    Science.gov (United States)

    Fenneni, Mohamed Amine; Latiri, Imed; Aloui, Asma; Rouatbi, Sonia; Chamari, Karim; Saad, Helmi Ben

    To examine the effects of Ramadan intermittent fasting (RIF) on the heart rate (HR) and oxyhaemoglobin saturation levels (oxy-sat) of boys at rest and during a six-minute walking test (6MWT). Eighteen boys (age: 11.9 ± 0.8 years, height: 153.00 ± 8.93 cm, body mass: 55.4 ± 18.2 kg), who fasted the entire month of Ramadan in 2012 for the first time in their lives, were included. The experimental protocol comprised four testing phases: two weeks before Ramadan (pre-R), the end of the second week of Ramadan (R-2), the end of the fourth week of Ramadan (R-4), and 10 to 12 days after the end of Ramadan (post-R). During each phase, participants performed the 6MWT at approximately 15:00. HR (expressed as percentage of maximal predicted HR) and oxy-sat (%) were determined at rest and in each minute of the 6MWT. R-4 HR values were lower than those of (1) pre-R (in the second minute), (2) R-2 (in the first and second minutes), and (3) post-R (in the first, second, fourth, fifth and sixth minutes). R-2 oxy-sat values were higher than those of pre-R (in the third minute) and those of post-R (in the fifth minute). Post-R oxy-sat values were lower than those of pre-R and R-4 in the fifth minute. These oxy-sat changes were not clinically significant since the difference was less than five points. In non-athletic children, their first RIF influenced their heart rate data but had a minimal effect on oxy-sat values.

  6. Exercise intervention may prevent depression.

    Science.gov (United States)

    He, S-B; Tang, W-G; Tang, W-J; Kao, X-L; Zhang, C-G; Wong, X-T

    2012-07-01

    Physical activity is an effective component of depression management. However, the mechanisms by which exercise affects behavioral disorders remain unclear. The present study was conducted to investigate mechanisms by which voluntary exercise ameliorates depression. Plasma cortisol levels and hippocampal monoamine neurotransmitters were measured. Chronic mild stress (CMS) was used to induce depression in a rat model. The rats were allowed to swim for 10 weeks as part of their exercise treatment. Depressive behavior was analyzed using an open-field test and a sucrose consumption test before and after exercise. Serum cortisol levels were measured by radioimmunoassay. The concentrations of monoamine neurotransmitters in the hippocampus were determined using high-performance liquid chromatography with electrochemical detection. The CMS rats showed behavioral improvement after exercise. Compared with the control, serum cortisol levels were significantly increased by CMS. The serotonin, dopamine, and norepinephrine levels in the hippocampi were significantly increased by exercise. These findings indicate that exercise reverses and prevents the decrease in serotonin and noradrenaline, and restores dopamine in the CMS model. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Compulsive exercise

    DEFF Research Database (Denmark)

    Lichtenstein, Mia Beck; Hinze, Cecilie Juul; Emborg Jannsen, Bolette

    2017-01-01

    in either International Classification of Diseases or Diagnostic and Statistical Manual of Mental Disorders. The aim of this literature review was to critically examine the research on links (comorbidity), risks (negative consequences), and challenges faced (problems in a treatment context). This review...... found that compulsive exercise is associated with eating disorder pathology, perfectionism, neuroticism, narcissism, and obsessive compulsive traits. The most prominent negative consequences were injuries, social impairment, and depression, but more research is needed to uncover the potential...... dysfunction resulting from compulsive exercise. As the condition is not recognized as a psychiatric disorder, studies on treatment interventions are sparse. Problems with compliance have been reported; therefore, motivational interviewing has been proposed as a treatment approach, in combination...

  8. Soil attributes as viable agents in red spruce mortality along the southern Appalachian highlands with applications as field and laboratory exercises for community college science courses

    Science.gov (United States)

    Ashbrook, Craig Monday

    The southern Appalachian highlands displaying peaks above 1500m frequently support a northern boreal forest. These highland forests sustain both red spruce and Fraser fir trees, which are typically aboriginal to the northeastern United States and southeastern Canada. Within the past century, these forests have declined at an unusual rate. Past studies have focused on the impacts of acid deposition and similar atmospheric pollutants. However, the scientific community found difficulty in establishing a cause-and-effect relationship between the decline and these atmospheric pollutants. This dissertation focuses on a heavily neglected and often overlooked factor, which creates restrictions in growth patterns and overall health of these boreal trees. That overlooked factor deals primarily with soil nutrients within a selected spruce-fir stand of the southern Appalachians. The research quantitatively analyzes soils for specific chemical and physical properties, with comparisons made to soils from the New England region where the spruces and firs grow indigenously. A fundamental part of understanding ecosystems is the environmental interrelationships within those ecosystems. This document organizes a series of laboratory exercises, which target community college science courses so student exploration of these interrelationships becomes an integral part of the laboratory procedures. By completing these various exercises, students become more aware of the connective character of nature as well as develop an appreciation of geography, the original environmental science. Although atmospheric pollutants should continue to be scrutinized, findings of this research document show that the natural characteristics of soils are clearly a limiting factor in the overall health and vitality of the southern boreal forests. Therefore, future research, regardless of the focus, should include soil characteristics as a viable factor in the health of these delicate forest-types.

  9. Influence of physical exercise on sex-hormone metabolism.

    Science.gov (United States)

    Keizer, H A; Poortman, J; Bunnik, G S

    1980-05-01

    We have studied the effects of short-term exercise on the degradation rate of estradiol (E2) measured as the metabolic clearance rate (MCRE2). Six young women (mean age 20.7 yr) volunteered for this study in which we investigated the influence of a submaximal bicycle ergometer load on the MCRE2. All measurements were done in the morning of the 7th to 10th day of the menstrual cycle. [3H]estradiol 17 beta ([3H]E2) was administered intravenously at a constant rate by an infusion pump. During the exercise period on the bicycle ergometer (70% VO2max, 10 min) and the recovery period (25% VO2max, 30 min), several blood samples were taken in which the [3H]E2 concentration was estimated. The results showed a strong decrease in the MCRE2 (range 18-67%) at the end of the work load for all the volunteers. At the end of the recovery period, the MCR was still lower than the basal value (range 30-50%). The possible mechanisms and relevance of these exercise-induced MCR changes of estradiol are discussed.

  10. Differences in ME and CFS Symptomology in Patients with Normal and Abnormal Exercise Test Results.

    Science.gov (United States)

    McManimen, Stephanie L; Jason, Leonard A

    2017-01-01

    Post-exertional malaise (PEM) is a cardinal symptom of myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS), which often distinguishes patients with this illness from healthy controls or individuals with exclusionary illnesses such as depression. However, occurrence rates for PEM fluctuate from subject to how the symptom is operationalized. One commonly utilized method is exercise testing, maximal or submaximal. Many patients with ME and CFS experience PEM after participating in these tests, and often show abnormal results. However, some patients still exhibit normal results after participating in the exercise testing. This study examined the differences between two patient groups with ME and CFS, those with normal results and those with abnormal results, on several PEM-related symptoms and illness characteristics. The results suggest those that displayed abnormal results following testing have more frequent and severe PEM, worse overall functioning, and are more likely to be bedbound than those that displayed normal results.

  11. Cerebral oxygenation and metabolism during exercise following three months of endurance training in healthy overweight males

    DEFF Research Database (Denmark)

    Seifert, T; Rasmussen, P; Brassard, P

    2009-01-01

    Endurance training improves muscular and cardiovascular fitness, but the effect on cerebral oxygenation and metabolism remains unknown. We hypothesized that 3 mo of endurance training would reduce cerebral carbohydrate uptake with maintained cerebral oxygenation during submaximal exercise. Healthy...... overweight males were included in a randomized, controlled study (training: n = 10; control: n = 7). Arterial and internal jugular venous catheterization was used to determine concentration differences for oxygen, glucose, and lactate across the brain and the oxygen-carbohydrate index [molar uptake of oxygen...... with a lower plasma epinephrine concentration (P exercising at 70% of maximal oxygen uptake (approximately 211 W). Before training, both OCI (3.9 +/- 0.9) and DeltaP(Mito)O(2) (-22 mmHg) decreased (P

  12. Radionuclide angiographic assessment of global and segmental left ventricular function at rest and during exercise after coronary artery bypass graft surgery

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Y.L.; Kalff, V.; Kelly, M.J.; Mason, P.J.; Currie, P.J.; Harper, R.W.; Anderson, S.T.; Federman, J.; Stirling, G.R.; Pitt, A.

    1982-11-01

    Left ventricular ejection fraction (LVEF) was measured by radionuclide angiography at rest and during supine bicycle exercise before and 3 months after coronary artery bypass graft surgery (CABG) in 20 patients with chronic stable angina. The right anterior oblique gated first-pass technique was used to assess LVEF response to maximal exercise (Wmax), while the left anterior oblique equilibrium-gated technique was used to assess LVEF and relative LV volume changes during graded submaximal execise. The five subjects in whom LVEF decreased significantly during exercise postoperatively all had one or more blocked or stenosed grafts. This study documents, by two independent radionuclide techniques, an improved LVEF during exercise at an increased maximal work capacity and rate-pressure product 3 months after successful CABG. (JMT)

  13. Oral antioxidants improve leg blood flow during exercise in patients with chronic obstructive pulmonary disease

    Science.gov (United States)

    Rossman, Matthew J.; Trinity, Joel D.; Garten, Ryan S.; Ives, Stephen J.; Conklin, Jamie D.; Barrett-O'Keefe, Zachary; Witman, Melissa A. H.; Bledsoe, Amber D.; Morgan, David E.; Runnels, Sean; Reese, Van R.; Zhao, Jia; Amann, Markus; Wray, D. Walter

    2015-01-01

    The consequence of elevated oxidative stress on exercising skeletal muscle blood flow as well as the transport and utilization of O2 in patients with chronic obstructive pulmonary disease (COPD) is not well understood. The present study examined the impact of an oral antioxidant cocktail (AOC) on leg blood flow (LBF) and O2 consumption during dynamic exercise in 16 patients with COPD and 16 healthy subjects. Subjects performed submaximal (3, 6, and 9 W) single-leg knee extensor exercise while LBF (Doppler ultrasound), mean arterial blood pressure, leg vascular conductance, arterial O2 saturation, leg arterial-venous O2 difference, and leg O2 consumption (direct Fick) were evaluated under control conditions and after AOC administration. AOC administration increased LBF (3 W: 1,604 ± 100 vs. 1,798 ± 128 ml/min, 6 W: 1,832 ± 109 vs. 1,992 ± 120 ml/min, and 9W: 2,035 ± 114 vs. 2,187 ± 136 ml/min, P exercise in COPD, whereas no effect was observed in healthy subjects. In addition, the AOC afforded a small, but significant, improvement in arterial O2 saturation only in patients with COPD. Thus, these data demonstrate a novel beneficial role of AOC administration on exercising LBF, O2 consumption, and arterial O2 saturation in patients with COPD, implicating oxidative stress as a potential therapeutic target for impaired exercise capacity in this population. PMID:26188020

  14. Oral antioxidants improve leg blood flow during exercise in patients with chronic obstructive pulmonary disease.

    Science.gov (United States)

    Rossman, Matthew J; Trinity, Joel D; Garten, Ryan S; Ives, Stephen J; Conklin, Jamie D; Barrett-O'Keefe, Zachary; Witman, Melissa A H; Bledsoe, Amber D; Morgan, David E; Runnels, Sean; Reese, Van R; Zhao, Jia; Amann, Markus; Wray, D Walter; Richardson, Russell S

    2015-09-01

    The consequence of elevated oxidative stress on exercising skeletal muscle blood flow as well as the transport and utilization of O2 in patients with chronic obstructive pulmonary disease (COPD) is not well understood. The present study examined the impact of an oral antioxidant cocktail (AOC) on leg blood flow (LBF) and O2 consumption during dynamic exercise in 16 patients with COPD and 16 healthy subjects. Subjects performed submaximal (3, 6, and 9 W) single-leg knee extensor exercise while LBF (Doppler ultrasound), mean arterial blood pressure, leg vascular conductance, arterial O2 saturation, leg arterial-venous O2 difference, and leg O2 consumption (direct Fick) were evaluated under control conditions and after AOC administration. AOC administration increased LBF (3 W: 1,604 ± 100 vs. 1,798 ± 128 ml/min, 6 W: 1,832 ± 109 vs. 1,992 ± 120 ml/min, and 9W: 2,035 ± 114 vs. 2,187 ± 136 ml/min, P exercise in COPD, whereas no effect was observed in healthy subjects. In addition, the AOC afforded a small, but significant, improvement in arterial O2 saturation only in patients with COPD. Thus, these data demonstrate a novel beneficial role of AOC administration on exercising LBF, O2 consumption, and arterial O2 saturation in patients with COPD, implicating oxidative stress as a potential therapeutic target for impaired exercise capacity in this population. Copyright © 2015 the American Physiological Society.

  15. Influence of obstructive sleep apnea syndrome in the fluctuation of the submaximal isometric torque of knee extensors in patients with early-grade osteoarthritis

    Science.gov (United States)

    Silva, Andressa; Mello, Marco T.; Serrão, Paula R.; Luz, Roberta P.; Bittencourt, Lia R.; Mattiello, Stela M.

    2015-01-01

    OBJECTIVE: The aim of this study was to investigate whether obstructive sleep apnea (OSA) alters the fluctuation of submaximal isometric torque of the knee extensors in patients with early-grade osteoarthritis (OA). METHOD: The study included 60 male volunteers, aged 40 to 70 years, divided into four groups: Group 1 (G1) - Control (n=15): without OA and without OSA; Group 2 (G2) (n=15): with OA and without OSA; Group 3 (G3) (n=15): without OA and with OSA; and Group 4 (G4) (n=15) with OA and with OSA. Five patients underwent maximal isometric contractions of 10 seconds duration each, with the knee at 60° of flexion to determine peak torque at 60°. To evaluate the fluctuation of torque, 5 submaximal isometric contractions (50% of maximum peak torque) of 10 seconds each, which were calculated from the standard deviation of torque and coefficient of variation, were performed. RESULTS: Significant differences were observed between groups for maximum peak torque, while G4 showed a lower value compared with G1 (p=0.005). Additionally, for the average torque exerted, G4 showed a lower value compared to the G1 (p=0.036). However, no differences were found between the groups for the standard deviation (p=0.844) and the coefficient of variation (p=0.143). CONCLUSION: The authors concluded that OSA did not change the parameters of the fluctuation of isometric submaximal torque of knee extensors in patients with early-grade OA. PMID:26443974

  16. Ventilatory function during exercise in multiple sclerosis and impact of training intervention: cross-sectional and randomized controlled trial.

    Science.gov (United States)

    Hansen, D; Wens, I; Keytsman, C; Verboven, K; Dendale, P; Eijnde, B O

    2015-10-01

    Patients with MS (pwMS) often experience resting ventilatory anomalies. Ventilatory function during exercise and impact of long-term training intervention remains however uncertain. The aim of this study was to examine the ventilatory function during exercise and impact of a 6-month training intervention in pwMS. Combination of a cross-sectional (part 1) and randomized controlled trial (part 2). University rehabilitation facility. Caucasian patients with MS and healthy controls. In part 1, the ventilatory function during submaximal endurance exercise was compared between pwMS (N.=37) and healthy participants (N.=15). In part 2, pwMS were then randomly assigned to a 6-month training intervention (N.=16) or usual care (N.=11). Following training intervention, ventilatory function during exercise was re-evaluated. Despite comparable relative exercise testing intensities between groups in part 1, significantly elevated steady-state exercise dead space/tidal volume ratio, O2 uptake and CO2 output equivalent, end-tidal O2 pressure, ratings of perceived exertion and lowered end-tidal CO2 pressure and O2 pulse was observed in pwMS (Ptraining intervention, ventilatory dysfunction remained present during endurance exercise (P>0.05). Patients with MS experience a ventilatory dysfunction during endurance exercise, which is related to worse exercise tolerance. This ventilatory anomaly remains present after long-term training intervention. Patients with MS experience ventilatory dysfunction during exercise. This dysfunction is related to exercise tolerance and ratings of perceived exertion. Long-term exercise training did not remediate this ventilatory dysfunction. The systematic examination of the pulmonary/cardiovascular system at rest and during exercise is recommended in MS.

  17. Effects of an 18-week exercise programme started early during breast cancer treatment: a randomised controlled trial.

    Science.gov (United States)

    Travier, Noémie; Velthuis, Miranda J; Steins Bisschop, Charlotte N; van den Buijs, Bram; Monninkhof, Evelyn M; Backx, Frank; Los, Maartje; Erdkamp, Frans; Bloemendal, Haiko J; Rodenhuis, Carla; de Roos, Marnix A J; Verhaar, Marlies; ten Bokkel Huinink, Daan; van der Wall, Elsken; Peeters, Petra H M; May, Anne M

    2015-06-08

    Exercise started shortly after breast cancer diagnosis might prevent or diminish fatigue complaints. The Physical Activity during Cancer Treatment (PACT) study was designed to primarily examine the effects of an 18-week exercise intervention, offered in the daily clinical practice setting and starting within 6 weeks after diagnosis, on preventing an increase in fatigue. This multi-centre controlled trial randomly assigned 204 breast cancer patients to usual care (n = 102) or supervised aerobic and resistance exercise (n = 102). By design, all patients received chemotherapy between baseline and 18 weeks. Fatigue (i.e., primary outcome at 18 weeks), quality of life, anxiety, depression, and physical fitness were measured at 18 and 36 weeks. Intention-to-treat mixed linear model analyses showed that physical fatigue increased significantly less during cancer treatment in the intervention group compared to control (mean between-group differences at 18 weeks: -1.3; 95 % CI -2.5 to -0.1; effect size -0.30). Results for general fatigue were comparable but did not reach statistical significance (-1.0, 95%CI -2.1; 0.1; effect size -0.23). At 18 weeks, submaximal cardiorespiratory fitness and several muscle strength tests (leg extension and flexion) were significantly higher in the intervention group compared to control, whereas peak oxygen uptake did not differ between groups. At 36 weeks these differences were no longer statistically significant. Quality of life outcomes favoured the exercise group but were not significantly different between groups. A supervised 18-week exercise programme offered early in routine care during adjuvant breast cancer treatment showed positive effects on physical fatigue, submaximal cardiorespiratory fitness, and muscle strength. Exercise early during treatment of breast cancer can be recommended. At 36 weeks, these effects were no longer statistically significant. This might have been caused by the control participants' high physical

  18. Effects of flunixin on cardiorespiratory, plasma lactate and stride length responses to intense treadmill exercise in Standardbred trotters.

    Science.gov (United States)

    Kallings, P; Persson, S G B; Essén-Gustavsson, B

    2010-11-01

    Since nonsteroidal anti-inflammatory drugs, such as flunixin, on account of their anti-inflammatory and analgesic properties, are used in both racing and equestrian sport horses, the question has been raised as to whether these drugs affect the physiological responses to exercise and thus performance potential. The aims of this investigation were to study the effects of flunixin on cardiorespiratory, metabolic and locomotor parameters in horses during intense treadmill exercise. Six Standardbred trotters underwent an incremental treadmill exercise test to fatigue, without drug and then after administration of flunixin meglumine (1.1 mg/kg bwt i.m.). Heart rate (HR), oxygen uptake and stride length were measured and venous blood samples drawn repeatedly during the test. Heart rates were found to be significantly higher at submaximal speeds, while the velocity causing a HR of 200 beats/min was significantly decreased after treatment with flunixin. Maximal HR and plasma lactate concentration 5 min after exercise were unchanged after medication. Flunixin caused higher plasma lactate concentrations at all speeds and the lactate threshold was decreased, compared with baseline values. Oxygen uptake levelled off at the highest velocities and did not change after flunixin treatment. Stride length was increased after treatment, although not at the highest velocities. The increased HR and lactate responses to exercise after flunixin treatment indicate that it does influence physiological responses, but does not improve the performance potential of clinically healthy horses. However, the lengthened stride during submaximal exercise after medication could imply undetected subclinical lameness, masked in some of the horses, i.e. they have performed with a longer stride at the cost of a higher heart rate and an increased lactate concentration. © 2010 EVJ Ltd.

  19. PHYSIOLOGICAL AND LEUKOCYTE SUBSET RESPONSES TO EXERCISE AND COLD EXPOSURE IN COLD-ACCLIMATIZED SKATERS

    Directory of Open Access Journals (Sweden)

    K. Kim

    2014-07-01

    Full Text Available We investigated physiological responses and changes in circulating immune cells following exercise in cold and thermoneutral conditions. Participants were short track skaters (n=9 who were acclimatized to cold conditions, and inline skaters (n=10 who were not acclimatized. All skaters were young, and skating at a recreational level three days per week for at least one year. Using a cross-over design, study variables were measured during 60 min of submaximal cycling (65% ·VO2max in cold (ambient temperature: 5±1°C, relative humidity: 41±9% and thermoneutral conditions (ambient temperature: 21±1°C, relative humidity: 35±5%. Heart rate, blood lactate and tympanic temperature were measured at rest, during exercise and recovery. Plasma cortisol, calprotectin and circulating blood cell numbers were measured before and after 60 min of cold or thermoneutral conditions, and during recovery from exercise. Heart rate was lower in both groups during exercise in cold versus thermoneutral conditions (P<0.05. The increase in total leukocytes during recovery was primarily due to an increase in neutrophils in both groups. The cold-acclimatized group activated neutrophils after exercise in cold exposure, whereas the non-acclimatized group activated lymphocyte and cortisol after exercise in cold exposure. Lymphocyte subsets significantly changed in both groups over time during recovery as compared to rest. Immediately after exercise in both groups, CD16+ and CD69+ cells were elevated compared to rest or before exercise in both conditions. Acclimatization to exercise in the cold does not appear to influence exercise-induced immune changes in cold conditions, with the possible exception of neutrophils, lymphocytes and cortisol concentration.

  20. Physiological and leukocyte subset responses to exercise and cold exposure in cold-acclimatized skaters.

    Science.gov (United States)

    Kim, K; Suzuki, K; Peake, J; Ahn, N; Ogawa, K; Hong, Ch; Kim, S; Lee, I; Park, J

    2014-03-01

    We investigated physiological responses and changes in circulating immune cells following exercise in cold and thermoneutral conditions. Participants were short track skaters (n=9) who were acclimatized to cold conditions, and inline skaters (n=10) who were not acclimatized. All skaters were young, and skating at a recreational level three days per week for at least one year. Using a cross-over design, study variables were measured during 60 min of submaximal cycling (65% [Formula: see text]O2max) in cold (ambient temperature: 5±1°C, relative humidity: 41±9%) and thermoneutral conditions (ambient temperature: 21±1°C, relative humidity: 35±5%). Heart rate, blood lactate and tympanic temperature were measured at rest, during exercise and recovery. Plasma cortisol, calprotectin and circulating blood cell numbers were measured before and after 60 min of cold or thermoneutral conditions, and during recovery from exercise. Heart rate was lower in both groups during exercise in cold versus thermoneutral conditions (Pcold-acclimatized group activated neutrophils after exercise in cold exposure, whereas the non-acclimatized group activated lymphocyte and cortisol after exercise in cold exposure. Lymphocyte subsets significantly changed in both groups over time during recovery as compared to rest. Immediately after exercise in both groups, CD16+ and CD69+ cells were elevated compared to rest or before exercise in both conditions. Acclimatization to exercise in the cold does not appear to influence exercise-induced immune changes in cold conditions, with the possible exception of neutrophils, lymphocytes and cortisol concentration.

  1. Neuromuscular adaptations to water-based concurrent training in postmenopausal women: effects of intrasession exercise sequence.

    Science.gov (United States)

    Pinto, Stephanie S; Alberton, Cristine L; Bagatini, Natália C; Zaffari, Paula; Cadore, Eduardo L; Radaelli, Régis; Baroni, Bruno M; Lanferdini, Fábio J; Ferrari, Rodrigo; Kanitz, Ana Carolina; Pinto, Ronei S; Vaz, Marco Aurélio; Kruel, Luiz Fernando M

    2015-02-01

    This study investigated the effects of different exercise sequences on the neuromuscular adaptations induced by water-based concurrent training in postmenopausal women. Twenty-one healthy postmenopausal women (57.14 ± 2.43 years) were randomly placed into two water-based concurrent training groups: resistance training prior to (RA, n = 10) or after (AR, n = 11) aerobic training. Subjects performed resistance and aerobic training twice a week over 12 weeks, performing both exercise types in the same training session. Upper (elbow flexors) and lower-body (knee extensors) one-repetition maximal test (1RM) and peak torque (PT) (knee extensors) were evaluated. The muscle thickness (MT) of upper (biceps brachii) and lower-body (vastus lateralis) was determined by ultrasonography. Moreover, the maximal and submaximal (neuromuscular economy) electromyographic activity (EMG) of lower-body (vastus lateralis and rectus femoris) was measured. Both RA and AR groups increased the upper- and lower-body 1RM and PT, while the lower-body 1RM increases observed in the RA was greater than AR (34.62 ± 13.51 vs. 14.16 ± 13.68 %). RA and AR showed similar MT increases in upper- and lower-body muscles evaluated. In addition, significant improvements in the maximal and submaximal EMG of lower-body muscles in both RA and AR were found, with no differences between groups. Both exercise sequences in water-based concurrent training presented relevant improvements to promote health and physical fitness in postmenopausal women. However, the exercise sequence resistance-aerobic optimizes the strength gains in lower limbs.

  2. The Gravity-Loading countermeasure Skinsuit (GLCS) and its effect upon aerobic exercise performance

    Science.gov (United States)

    Attias, Julia; Philip, A. T. Carvil; Waldie, James; Russomano, Thais; Simon, N. Evetts; David, A. Green

    2017-03-01

    The Russian Pingvin suit is employed as a countermeasure to musculoskeletal atrophy in microgravity, though its 2-stage loading regime is poorly tolerated. The Gravity-Loading Countermeasure Skinsuit (GLCS) has been devised to comfortably compress the body via incrementally increasing longitudinal elastic-fibre tensions from the shoulders to the feet. We tested whether the Mk III GLCS was a feasible adjunct to sub-maximal aerobic exercise and resulting VO2Max predictions. Eight healthy subjects (5♂, 28±6 yr) performed cycle ergometry at 75% VO2Max (derived from an Astrand-Rhyming protocol) whilst wearing a GLCS and gym clothing (GYM). Ventilatory parameters, heart rate (HR), core temperature (TC), and blood lactate (BL) were recorded along with subjective perceived exertion, thermal comfort, movement discomfort and body control. Physiological and subjective responses were compared over TIME and between GYM and GLCS (ATTIRE) with 2-way repeated measures ANOVA and Wilcoxon tests respectively. Resultant VO2Max predictions were compared with paired t-tests between ATTIRE. The GLCS induced greater initial exercise ventilatory responses which stabilised by 20 min. HR and TC continued to rise from 5 min irrespective of ATTIRE, whereas BL was greater in the GLCS at 20 min. Predicted V O2Max did not differ with ATTIRE, though some observed differences in HR were noteworthy. All subjective ratings were exacerbated in the GLCS. Despite increased perception of workload and initial ventilatory augmentations, submaximal exercise performance was not impeded. Whilst predicted VO2Max did not differ, determination of actual VO2Max in the GLCS is warranted due to apparent modulation of the linear HR-VO2 relationship. The GLCS may be a feasible adjunct to exercise and potential countermeasure to unloaded-induced physiological deconditioning on Earth or in space.

  3. Bengt Saltin and exercise physiology: a perspective.

    Science.gov (United States)

    Joyner, Michael J

    2017-01-01

    This perspective highlights some of the key contributions of Professor Bengt Saltin (1935-2014) to exercise physiology. The emergence of exercise physiology from work physiology as his career began is discussed as are his contributions in a number of areas. Saltin's open and question-based style of leadership is a model for the future of our field.

  4. Aerobic exercise intensity in breast cancer patients: a preliminary investigation.

    Science.gov (United States)

    Evans, Elizabeth S; Battaglini, Claudio L; Groff, Diane G; Hackney, A C

    2009-06-01

    This study compared the heart rate (HR), rate of perceived exertion (RPE), and blood lactate (BL) responses to aerobic exercise between posttreated breast cancer patients and apparently healthy, age-matched controls. Seven patients and 7 control subjects underwent a submaximal treadmill test for the estimation of Vo(2max). Exercise intensities of 40%, 60%, and 70% of Vo(2max) were calculated from the treadmill test and randomly examined between groups during three 9-minute exercise bouts on 3 different days. Independent samples t tests were used to examine the HR, RPE, and BL responses at each intensity between groups. No significant differences were observed between the control and patient groups for HR, RPE, and BL at 40% (101 +/- 9 vs 101 +/- 11 bpm, P = .979; 8 +/- 1 vs 9 +/- 3, P = .237; and 1.11 +/- 0.73 vs 1.26 +/- 0.64 mmol/L, P = .188, respectively) and 60% (127 +/- 17 vs 117 +/- 13 bpm, P = .523; 12 +/- 2 vs 11 +/- 3, P = .267, and 3.83 +/- 2.48 vs 2.23 +/- 1.65 mmol/L, P = .237, respectively) of Vo(2max) . At 70% of Vo(2max), no significant differences were found for HR (151 +/- 27 vs 135 +/- 13 bpm, P = .704) and RPE (14 +/- 1 vs 13 +/- 3, P = .181), but lower BL responses were observed in the patient group (7.70 +/- 1.62 vs 3.29 +/- 1.08 mmol/L, P exercise at moderate or higher intensities so that safer aerobic exercise prescriptions can be developed for this population.

  5. The effect of time of day and exercise on platelet functions and platelet-neutrophil aggregates in healthy male subjects.

    Science.gov (United States)

    Aldemir, Hatice; Kiliç, Nedret

    2005-12-01

    Platelet activation state changes by exercise. The effect of exercise time on platelet activation state and formation of platelet-neutrophil aggregates are not known yet. In this study the effect of exercise and time of day were examined on platelet activity with platelet-neutrophil aggregates. Ten moderately active males aged 27+/- 1.63 (mean+/-S.D.) years completed sub-maximal (70% VO(2max)) exercise trials for 30 min. Blood pressure (BP) was recorded. Venous blood samples were obtained at rest, immediately post-exercise and after 30 min of recovery. Whole blood was analysed for haematocrit (Hct), haemoglobin (Hb), platelet count (PC), mean platelet count (MPV) and platelet aggregation (PA). Platelet-neutrophil aggregates and beta-thromboglobulin (beta-TG) levels were assayed. Platelet count showed significant increase after morning exercise ((236+/- 32)x10(9) l(-1) versus (202+/- 34)x10(9) l(-1) baseline, p Exercise resulted in significantly lower MPV after the evening exercise (9.16+/- 0.5 fl versus 9.65+/- 0.36 fl, p exercise and the recovery aggregation levels were significantly different at two different times of the day (68+/- 20% a.m. versus 80+/- 12% p.m., p exercises. Exercise-induced platelet-neutrophil aggregates were higher in the evening (10.7+/- 1.3% p.m. versus 6.4+/- 1.8% a.m., p exercise can cause platelet- neutrophil aggregates. In addition, time of day has an effect on platelet activation related events. Circadian variations of physiological parameters may have an effect on thrombus formation by platelet activation.

  6. BIological Psychology, Exercise, and Stress.

    Science.gov (United States)

    Dishman, Rod K.

    1994-01-01

    Reviews theory and methods used by the field of biological psychology to study stress that have potential for understanding how behavioral and biological adaptations to the stress of exercise are integrated. The overview focuses on anxiety, depression, and physiological responsiveness to nonexercise stressors from the perspective of biological…

  7. Adolescents and Exercise Induced Asthma

    Science.gov (United States)

    Hansen, Pamela; Bickanse, Shanna; Bogenreif, Mike; VanSickle, Kyle

    2008-01-01

    This article defines asthma and exercise induced asthma, and provides information on the triggers, signs, and symptoms of an attack. It also gives treatments for these conditions, along with prevention guidelines on how to handle an attack in the classroom or on the practice field. (Contains 2 tables and 1 figure.)

  8. Exercise After Pregnancy

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Exercise After Pregnancy Home For Patients Search FAQs Exercise After Pregnancy ... Pregnancy FAQ131, June 2015 PDF Format Exercise After Pregnancy Labor, Delivery, and Postpartum Care What are some ...

  9. Logic functions and equations examples and exercises

    CERN Document Server

    Steinbach, Bernd

    2009-01-01

    With a free, downloadable software package available to help solve the exercises, this book focuses on practical and relevant problems that arise in the field of binary logics, with its two main applications - digital circuit design, and propositional logics.

  10. Effects of walking and strength training on resting and exercise cardiovascular responses in patients with intermittent claudication.

    Science.gov (United States)

    Grizzo Cucato, G; de Moraes Forjaz, C L; Kanegusuku, H; da Rocha Chehuen, M; Riani Costa, L A; Wolosker, N; Kalil Filho, R; de Fátima Nunes Marucci, M; Mendes Ritti-Dias, R

    2011-09-01

    Exercise training is recommended as the first-line therapy for intermittent claudication patients. However, the effects of exercise therapy on cardiovascular function of these patients have been poorly studied. The aim of this study is to compare the effects of walking and strength training on cardiovascular responses assessed at rest and during exercise in patients with intermittent claudication. Thirty-four patients with stable symptoms of intermittent claudication were randomized into two groups: strength training (ST) consisting of eight exercises, three sets of 10 repetitions, intensity of 11 - 13 on 15-grade Borg scale, 2-min interval between sets; and walking training (WT) consisting of walking on a treadmill, 15 bouts of 2-min, intensity of 11 - 13 on 15-grade Borg scale, with a 2-min interval between bouts. Before and after 12 weeks, blood pressure, heart rate and rate pressure product were measured at rest and during a progressive treadmill test until maximal claudication pain. Fifteen patients in each group completed the training program. After the training programs, resting systolic blood pressure (ST:-6 ± 13 mmHg and WT:-3 ± 18 mmHg, P = .04), heart rate (ST: -6 ± 10 bpm and WT:-2 ± 9 bpm, P = .03), and rate pressure product (ST:-1485 ± 1442 mmHg*bpm and WT:- 605 ± 2145 mmHg*bpm, P = .01) decreased significantly and similarly in both groups. Submaximal systolic blood pressure (ST: -14 ± 23 mmHg and WT:-6 ± 23 mmHg, P = .02), and rate pressure product (ST:-1579 ± 3444 mmHg*bpm and WT: -1264 ± 3005 mmHg*bpm, P = .04) decreased significantly and similarly in both groups. There were no changes in submaximal heart rate after ST and WT. Maximal systolic blood pressure, heart rate, and rate pressure product did not change in either group, although maximal exercise time increased similarly in the ST and WT groups (+31 ± 19 %, and +31 ± 32 %, respectively, P trainings promoted similar increases in walking capacity and decreases in resting and

  11. Concentrically trained cyclists are not more susceptible to eccentric exercise-induced muscle damage than are stretch-shortening exercise-trained runners.

    Science.gov (United States)

    Snieckus, Audrius; Kamandulis, Sigitas; Venckūnas, Tomas; Brazaitis, Marius; Volungevičius, Gintautas; Skurvydas, Albertas

    2013-03-01

    Here, we test the hypothesis that continuous concentric exercise training renders skeletal muscles more susceptible to damage in response to eccentric exercise. Elite road cyclists (CYC; n = 10, training experience 8.1 ± 2.0 years, age 22.9 ± 3.7 years), long-distance runners (LDR; n = 10, 9.9 ± 2.3 years, 24.4 ± 2.5 years), and healthy untrained (UT) men (n = 10; 22.4 ± 1.7 years) performed 100 submaximal eccentric contractions at constant angular velocity of 60° s(-1). Concentric isokinetic peak torque, isometric maximal voluntary contraction (MVC), and electrically induced knee extension torque were measured at baseline and immediately and 48 h after an eccentric exercise bout. Muscle soreness was assessed and plasma creatine kinase (CK) activity was measured at baseline and 48 h after exercise. Voluntary and electrically stimulated knee extension torque reduction were significantly greater (p < 0.05) in UT than in LDR and CYC. Immediately and 48 h after exercise, MVC decreased by 32 % and 20 % in UT, 20 % and 5 % in LDR, and 25 % and 6 % in CYC. Electrically induced 20 Hz torque decreased at the same times by 61 and 29 % in UT, 40 and 17 % in LDR, and 26 and 14 % in CYC. Muscle soreness and plasma CK activity 48 h after exercise did not differ significantly between athletes and UT subjects. In conclusion, even though elite endurance athletes are more resistant to eccentric exercise-induced muscle damage than are UT people, stretch-shortening exercise-trained LDR have no advantage over concentrically trained CYC.

  12. Pediatric Exercise Science: A Brief Overview.

    Science.gov (United States)

    Rowland, Thomas

    2016-05-01

    Interest in the physiological responses to exercise unique to the pediatric age group has grown exponentially over the past 50 years. A number of issues surrounding children's exercise have been particularly responsible for this trend, particularly a) recognition of the health benefits of exercise in youth, b) the growing involvement of young persons in highly intense levels of sports play, and c) the role that exercise may play in the diagnosis and management of children with chronic disease. As a consequence, current research to date has provided a comprehensive picture of the features specific to children's response to exercise. Future challenges facing the field of pediatric exercise science involve translating this information into practical guidelines which can be applied to the realms of clinical medical practice, preventive health initiatives, and athletic training regimens which are appropriate for this age group.

  13. An analysis of undergraduate exercise science programs: an exercise science curriculum survey.

    Science.gov (United States)

    Elder, Craig L; Pujol, Thomas J; Barnes, Jeremy T

    2003-08-01

    Undergraduate exercise science programs develop curricula by referring to standards set by professional organizations. A web-based survey was administered to 235 institutions with exercise science undergraduate programs to evaluate their adherence to stated curricular guidelines. Results indicate that 29% of institutions considered American College of Sports Medicine (ACSM) Knowledge, skills, and abilities (KSAs); 33% both ACSM and National Association for Sport and Physical Education (NASPE) guidelines; 6% ACSM, NASPE, and National Strength and Conditioning Association (NSCA); 8% ACSM, NASPE, NSCA, and American Society of Exercise Physiologists, and 5% NASPE. The two largest subgroups had good compliance with the areas of exercise physiology, biomechanics, and human anatomy and physiology. However, neither subgroup adhered to the areas of exercise prescription, testing, and implementation; exercise and aging; or exercise with special populations. Regardless of the implemented guideline(s), most institutions placed minimal emphasis on areas related to health promotion and many curricula did not require any field experience.

  14. Dietary nitrate supplementation increases acute mountain sickness severity and sense of effort during hypoxic exercise.

    Science.gov (United States)

    Rossetti, Gabriella M K; Macdonald, Jamie H; Wylie, Lee J; Little, Samuel J; Newton, Victoria; Wood, Benjamin; Hawkins, Kieran A; Beddoe, Rhys; Davies, Hannah E; Oliver, Samuel J

    2017-10-01

    Dietary nitrate supplementation enhances sea level performance and may ameliorate hypoxemia at high altitude. However, nitrate may exacerbate acute mountain sickness (AMS), specifically headache. This study investigated the effect of nitrate supplementation on AMS symptoms and exercise responses with 6-h hypoxia. Twenty recreationally active men [age, 22 ± 4 yr, maximal oxygen consumption (V̇o2max), 51 ± 6 ml·min-1·kg-1, means ± SD] completed this randomized double-blinded placebo-controlled crossover study. Twelve participants were classified as AMS- on the basis of Environmental Symptoms Questionnaire [Acute Cerebral Mountain Sickness score (AMS-C)] five participants were classified as AMS+ on the basis of AMS-C ≥0.7 on placebo. Five days of nitrate supplementation (70-ml beetroot juice containing ~6.4 mmol nitrate daily) increased plasma NO metabolites by 182 µM compared with placebo but did not reduce AMS or improve exercise performance. After 4-h hypoxia [inspired O2 fraction ([Formula: see text]) = 0.124], nitrate increased AMS-C and headache severity (visual analog scale; whole sample ∆10 [1, 20] mm, mean difference [95% confidence interval]; P = 0.03) compared with placebo. In addition, after 5-h hypoxia, nitrate increased sense of effort during submaximal exercise (∆7 [-1, 14]; P = 0.07). In AMS-, nitrate did not alter headache or sense of effort. In contrast, in AMS+, nitrate increased headache severity (∆26 [-3, 56] mm; P = 0.07), sense of effort (∆14 [1, 28]; P = 0.04), oxygen consumption, ventilation, and mean arterial pressure during submaximal exercise. On the next day, in a separate acute hypoxic exercise test ([Formula: see text] = 0.141), nitrate did not improve time to exhaustion at 80% hypoxic V̇o2max In conclusion, dietary nitrate increases AMS and sense of effort during exercise, particularly in those who experience AMS. Dietary nitrate is therefore not recommended as an AMS prophylactic or ergogenic aid in

  15. Exercise Equipment: Neutral Buoyancy

    Science.gov (United States)

    Shackelford, Linda; Valle, Paul

    2016-01-01

    Load Bearing Equipment for Neutral Buoyancy (LBE-NB) is an exercise frame that holds two exercising subjects in position as they apply counter forces to each other for lower extremity and spine loading resistance exercises. Resistance exercise prevents bone loss on ISS, but the ISS equipment is too massive for use in exploration craft. Integrating the human into the load directing, load generating, and motion control functions of the exercise equipment generates safe exercise loads with less equipment mass and volume.

  16. Biology of exercise

    National Research Council Canada - National Science Library

    .... JBE publishes work from sport injuries, exercise physiology, sport rehabilitation, disease and exercise, sport psychology, sport nutrition, sport biomechanics, sport pedagogy, sport philosophy, sport...

  17. Whole-body fat oxidation increases more by prior exercise than overnight fasting in elite endurance athletes.

    Science.gov (United States)

    Andersson Hall, Ulrika; Edin, Fredrik; Pedersen, Anders; Madsen, Klavs

    2016-04-01

    The purpose of this study was to compare whole-body fat oxidation kinetics after prior exercise with overnight fasting in elite endurance athletes. Thirteen highly trained athletes (9 men and 4 women; maximal oxygen uptake: 66 ± 1 mL·min(-1)·kg(-1)) performed 3 identical submaximal incremental tests on a cycle ergometer using a cross-over design. A control test (CON) was performed 3 h after a standardized breakfast, a fasting test (FAST) 12 h after a standardized evening meal, and a postexercise test (EXER) after standardized breakfast, endurance exercise, and 2 h fasting recovery. The test consisted of 3 min each at 30%, 40%, 50%, 60%, 70%, and 80% of maximal oxygen uptake and fat oxidation rates were measured through indirect calorimetry. During CON, maximal fat oxidation rate was 0.51 ± 0.04 g·min(-1) compared with 0.69 ± 0.04 g·min(-1) in FAST (P < 0.01), and 0.89 ± 0.05 g·min(-1) in EXER (P < 0.01). Across all intensities, EXER was significantly higher than FAST and FAST was higher than CON (P < 0.01). Blood insulin levels were lower and free fatty acid and cortisol levels were higher at the start of EXER compared with CON and FAST (P < 0.05). Plasma nuclear magnetic resonance-metabolomics showed similar changes in both EXER and FAST, including increased levels of fatty acids and succinate. In conclusion, prior exercise significantly increases whole-body fat oxidation during submaximal exercise compared with overnight fasting. Already high rates of maximal fat oxidation in elite endurance athletes were increased by approximately 75% after prior exercise and fasting recovery.

  18. Effects of Three-Day Bed Rest on Physiological Responses to Graded Exercise in Endurance Athletes, Body Builders and Sedentary Men

    Science.gov (United States)

    Smorawinski, J.; Nazar, K.; Kaciuza-Uscilko, H.; Kaminska, E.; Cybulski, G.; Kodrzycka, A.; Bice, B.; Greenleaf, J. E.; Sun, Sid (Technical Monitor)

    2001-01-01

    To test the hypotheses that short-term bed rest (BR) deconditioning influences metabolic, cardiorespiratory and neurohormonal responses to exercise and that these effects depend on the subjects' training status 12 sedentary men, and 10 endurance- and 10 strength-trained athletes were submitted to three-day BR. Before and after BR they performed incremental exercise test until volitional exhaustion. Respiratory gas exchange and HR were recorded continuously and stroke volume (SV) was measured at submaximal loads. Blood was taken for lactate [LA], adrenaline [A], noradrenaline, [NA], renting activity (PRA), growth hormone [hGH], testosterone and cortisol determination. Reduction of peak oxygen uptake (VO2peak) after BR was greater in the endurance athletes (than in the remaining groups (17 % vs. 100%). Decrements in VO2peak correlated positively with the initial values (r = 0.73, p less than 0.001). Resting and exercise respiratory exchange ratios were increased in athletes. Cardiac output was unchanged by BR in all groups, but exercise HR was increased and SV diminished in the sedentary subjects. The submaximal [LA] and [LA] thresholds were decreased the in endurance athletes from 71 to 60 %VO2 peak (p less than 0.001); they also had an earlier increase in [NA], and an attenuated increase in [hGH), and accentuated PRA and cortisol elevations during exercise. These effects were insignificant in the remaining subjects. In conclusion: reduction of exercise performance and modifications in neurohormonal response to exercise after BR depend on the previous level and mode of physical training, being the most pronounced in the endurance athletes.

  19. The effect of a standard whole blood donation on oxygen uptake and exercise capacity: a systematic review and meta-analysis.

    Science.gov (United States)

    Van Remoortel, Hans; De Buck, Emmy; Compernolle, Veerle; Deldicque, Louise; Vandekerckhove, Philippe

    2017-02-01

    Blood is a life-saving product for many people worldwide. Voluntary blood donation serves the demand for blood but there are concerns among potential donors about the impact of blood loss on exercise performance. This systematic review aimed to collect the best available evidence of the effect of a standard whole blood donation on aerobic exercise performance. Studies from six databases dealing with a standard whole blood donation (400-500 mL) followed by (sub)maximal exercise were retained. The outcomes included exercise-related blood variables (hemoglobin [Hb] concentration, hematocrit, and red blood cell count) and endurance exercise variables ((sub)maximal oxygen uptake, peak work rate, and time to exhaustion). Overall effects at different time points postdonation were investigated by performing meta-analyses and calculating mean differences (and 95% confidence intervals). The GRADE methodology (Grades of Recommendation, Assessment, Development, and Evaluation) was used to assess the quality of evidence. We identified 6237 references and finally included 18 before-after studies of low quality. Twenty-four to 48 hours after a blood donation, 1) Hb concentration was reduced (7% decrease) until 14 days after the blood donation (4% decrease), 2) maximal oxygen uptake (VO2max ) was lower (7% decrease), and 3) a reduction in maximal exercise capacity (10% decrease) was present. The best available evidence indicates that a standard whole blood donation (400-500 mL) leads to small but potentially physiologically important reductions in Hb levels, VO2max , and maximal exercise capacity in the first 2 days after the blood donation. © 2016 AABB.

  20. Quantification of Internal Stress-Strain Fields in Human Tendon: Unraveling the Mechanisms that Underlie Regional Tendon Adaptations and Mal-Adaptations to Mechanical Loading and the Effectiveness of Therapeutic Eccentric Exercise

    Science.gov (United States)

    Maganaris, Constantinos N.; Chatzistergos, Panagiotis; Reeves, Neil D.; Narici, Marco V.

    2017-01-01

    of the stress created by the exercise and is not only reliant upon the type of muscle contraction performed. To better understand the micromechanical behavior and regional adaptability/mal-adaptability of tendon tissue it is important to estimate its internal stress-strain fields. Recent relevant advancements in numerical techniques related to tendon loading are discussed. PMID:28293194

  1. Perception of exercise difficulty predicts weight regain in formerly overweight women.

    Science.gov (United States)

    Brock, David W; Chandler-Laney, Paula C; Alvarez, Jessica A; Gower, Barbara A; Gaesser, Glenn A; Hunter, Gary R

    2010-05-01

    It has been previously reported that overweight and obese individuals perceive exercise as more difficult than their lean counterparts, and this difference may not be solely attributed to physiological differences. Therefore, we tested the hypothesis that individual differences in the perception of exercise difficulty during exercise, independent of concurrently measured physiological markers of exertion, are predictive of weight regain, after completion of a weight loss program. A total of 113 formerly overweight women who had previously completed a weight-loss program to achieve a normal body weight (BMI perceived exertion (rating of perceived exertion (RPE)) were recorded. Weight gain was assessed following a subsequent 1-year free-living period. Average weight regain 1 year following the intervention was 5.46 +/- 3.95 kg. In regression modeling, RPE (beta = 0.21, P = 0.01), but not physiological exertion (beta = 0.02, P = 0.81), during the submaximal exercise task was positively associated with 1-year weight regain following weight loss in premenopausal women, independent of measured confounding variables. The association between RPE and weight regain suggests that perception of exercise difficulty is an important predictor of weight regain following a weight-loss intervention.

  2. The chondrogenic response to exercise in the proximal femur of normal and mdx mice

    Directory of Open Access Journals (Sweden)

    Nye David J

    2010-09-01

    Full Text Available Abstract Background Submaximal exercise is used in the management of muscular dystrophy. The effects of mechanical stimulation on skeletal development are well understood, although its effects on cartilage growth have yet to be investigated in the dystrophic condition. The objective of this study was to investigate the chondrogenic response to voluntary exercise in dystrophin-deficient mice. Methods Control and dystrophin-deficient (mdx mice were divided into sedentary and exercise-treated groups and tested for chondral histomorphometric differences at the proximal femur. Results Control mice ran 7 km/week further than mdx mice on average, but this difference was not statistically significant (P > 0.05. However, exercised control mice exhibited significantly enlarged femur head diameter, articular cartilage thickness, articular cartilage tissue area, and area of calcified cartilage relative to sedentary controls and exercised mdx mice (P Conclusions Mdx mice exhibit a reduced chondrogenic response to increased mechanical stimulation relative to controls. However, no significant reduction in articular dimensions was found, indicating loss of chondral tissue may not be a clinical concern with dystrophinopathy.

  3. Utilizing small nutrient compounds as enhancers of exercise-induced mitochondrial biogenesis

    Directory of Open Access Journals (Sweden)

    Daniel M Craig

    2015-10-01

    Full Text Available Endurance exercise, when performed regularly as part of a training program, leads to increases in whole-body and skeletal muscle-specific oxidative capacity. At the cellular level, this adaptive response is manifested by an increased number of oxidative fibres (Type I and IIA myosin heavy chain, an increase in capillarity and an increase in mitochondrial biogenesis. The increase in mitochondrial biogenesis (increased volume and functional capacity is fundamentally important as it leads to greater rates of oxidative phosphorylation and an improved capacity to utilize fatty acids during sub-maximal exercise. Given the importance of mitochondrial biogenesis for skeletal muscle performance, considerable attention has been given to understanding the molecular cues stimulated by endurance exercise that culminate in this adaptive response. In turn, this research has led to the identification of pharmaceutical compounds, functional foods and small nutritional bioactive ingredients that appear able to amplify exercise-responsive signaling pathways in skeletal muscle. The aim of this review is to discuss these purported exercise mimetics and bioactive ingredients in the context of mitochondrial biogenesis in skeletal muscle. We will examine proposed modes of action, discuss evidence of application in skeletal muscle in vivo and finally comment on the feasibility of such approaches to support endurance-training applications in humans.

  4. The responses of glabrous and nonglabrous skin microcirculation to graded dynamic exercise and its recovery.

    Science.gov (United States)

    Potočnik, N; Lenasi, H

    2016-11-04

    This study investigated the responses of skin blood flow (SkBF) in glabrous and nonglabrous skin to graded submaximal dynamic exercise and its recovery. We enrolled eight healthy young men with comparable maximal oxygen uptake (VO2max). Laser-Doppler flux (LDF) was assessed on the finger pulp (glabrous site) and the volar forearm (nonglabrous site) simultaneously with skin temperature, heart rate and blood pressure; cutaneous vascular conductance (CVC) was calculated. Subjects were monitored before (baseline), during and 25 minutes after incremental cycling. CVC in the pulp decreased with the onset of exercise (0.53±0.09AUmmHg-1 vs. baseline 1.23±0.25AUmmHg-1, p = 0.006), and persisted low until exercise cessation, whereas CVC in the forearm started to increase at 60% of subjects' VO2max, attaining its maximum at the highest exercise load (0.44±0.11AUmmHg-1 vs. baseline 0.12±0,03AUmmHg-1, p = 0.017). In the recovery, CVC in the pulp attained a higher plateau value compared to baseline (1.51±0.22AUmmHg-1, p = 0.021), interrupted by abrupt transient falls of CVC. On the forearm, CVC subsequently returned to its baseline. SkBF of glabrous and nonglabrous sites adjust in an opposite manner to graded exercise load and also differ during recovery.

  5. Exercise thermoregulation in men after 1 and 24-hours of 6 degrees head-down tilt

    Science.gov (United States)

    Ertl, A. C.; Dearborn, A. S.; Weidhofer, A. R.; Bernauer, E. M.; Greenleaf, J. E.

    2000-01-01

    BACKGROUND: Exercise thermoregulation is dependent on heat loss by increased skin blood flow (convective and conductive heat loss) and through enhanced sweating (evaporative heat loss). Reduction of plasma volume (PV), increased plasma osmolality, physical deconditioning, and duration of exposure to simulated and actual microgravity reduces the ability to thermoregulate during exercise. HYPOTHESIS: We hypothesized that 24 h of head down tilt (HDT24) would alter thermoregulatory responses to a submaximal exercise test and result in a higher exercise rectal temperature (Tre) when compared with exercise Tre after 1 h of head down tilt (HDT1). METHODS: Seven men (31+/-SD 6 yr, peak oxygen uptake (VpO2peak) of 44+/-6 ml x kg(-1) x min(-1)) were studied during 70 min of supine cycling at 58+/-SE 1.5% VO2peak at 22.0 degrees C Tdb and 47% rh. RESULTS: Relative to pre-tilt sitting chair rest data, HDT1 resulted in a 6.1+/-0.9% increase and HDT24 in a 4.3+/-2.3% decrease in PV (delta = 10.4% between experiments, pthermoregulation), the Tre offset could have been caused by the HDT-induced hypovolemia.

  6. Can exercise mimetics substitute for exercise?

    DEFF Research Database (Denmark)

    Richter, Erik; Kiens, Bente; Wojtaszewski, Jørgen

    2008-01-01

    Exercise leads to changes in muscle phenotype with important implications for exercise performance and health. A recent paper in Cell by Narkar et al. (2008) shows that many of the adaptations in muscle phenotype elicited by exercise can be mimicked by genetic manipulation and drug treatment...

  7. Exercise, lifestyle, and your bones

    Science.gov (United States)

    Osteoporosis - exercise; Low bone density - exercise; Osteopenia - exercise ... To build up bone density, the exercise must make your muscles pull on your bones. These are called weight-bearing exercises. Some of them are: Brisk ...

  8. Exercise therapy for patellofemoral pain syndrome.

    Science.gov (United States)

    Heintjes, E; Berger, M Y; Bierma-Zeinstra, S M A; Bernsen, R M D; Verhaar, J A N; Koes, B W

    2003-01-01

    Patellofemoral pain syndrome (PFPS) is a common problem among adolescents and young adults, characterised by retropatellar pain (behind the kneecap) or peripatellar pain (around the kneecap) when ascending or descending stairs, squatting or sitting with flexed knees. Etiology, structures causing the pain and treatment methods are all debated in literature, but consensus has not been reached so far. Exercise therapy to strengthen the quadriceps is often prescribed, though its efficacy is still debated. This review aims to summarise the evidence of effectiveness of exercise therapy in reducing anterior knee pain and improving knee function in patients with PFPS. We searched the Cochrane Musculoskeletal Injuries Group and Cochrane Rehabilitation and Related Therapies Field specialised registers, the Cochrane Controlled Trials Register, PEDro - The Physiotherapy Evidence Database, MEDLINE, EMBASE, CINAHL, up till December 2001 for controlled trials (randomised or not) comparing exercise therapy with control groups, or comparing different types of exercise therapy. Only trials focusing on exercise therapy in patients with PFPS were considered. Trials in patients with other diagnoses such as tendinitis, Osgood Schlatter syndrome, bursitis, traumatic injuries, osteoarthritis, plica syndrome, Sinding-Larssen-Johansson syndrome and patellar luxations were excluded. From 750 publications 12 trials were selected. All included trials studied quadriceps strengthening exercises. Outcome assessments for knee pain and knee function in daily life were used in a best evidence synthesis to summarise evidence for effectiveness. One high and two low quality studies used a control group not receiving exercise therapy. Significantly greater pain reduction in the exercise groups was found in one high and one low quality study, though at different time points. Only one low quality study reported significantly greater functional improvement with exercise. Five studies compared exercise

  9. Aerobic exercise supplemented with muscular endurance training improves onset of blood lactate accumulation.

    Science.gov (United States)

    Farrell, John W; Lantis, David J; Ade, Carl J; Cantrell, Greg S; Larson, Rebecca D

    2017-05-05

    Studies have shown that when aerobic exercise is supplemented with muscular endurance training metabolic adaptions occur that result in the delay of the onset of blood lactate accumulation (OBLA). However, previous studies have not explored any submaximal cardiorespiratory adaptations that may result from this training protocol. The aim of the current investigation was to evaluate the effect of supplementing an aerobic exercise training program with a muscular endurance training program on various cardiorespiratory and metabolic measurements. Fourteen aerobically active men performed an incremental exercise test to determine the OBLA, gas exchange threshold (GET), and maximal oxygen uptake (VO2max). Maximal strength was measured using 1-repetition max (1-RM) for leg press (LP), leg curl (LC), and leg extension (LE). Eight subjects supplemented their aerobic activity (EX group) with 8 weeks of muscular endurance training, while six continued their regular aerobic activity (CON group). No significant group differences were observed for all pretraining variables. Following eight weeks of training no significant differences in body mass, GET, and VO2max were observed for either group. However, the EX group showed a significant improvement for both absolute and relative VO2 at OBLA compared to the CON group. LC and LE 1-RM assessments for the EX group showed a significant improvement compared to CON group. Muscular endurance training did not improve GET and VO2max, but significantly increased VO2 at OBLA, LP, and LC. These findings suggest that this training protocol maybe useful in the development of submaximal aerobic performance and leg strength for endurance athletes.

  10. Effect of exercise intensity on exercise and post exercise energy ...

    African Journals Online (AJOL)

    The aim of this study was to determine if exercise and post exercise energy expenditure are affected by the intensity of exercise during a set distance of 4km walking and/or jogging. Subjects for this study were 12 moderately obese females with mean fat percentage of 31.7±6.3% and mean age of 38.2±4.6 years. For the low ...

  11. Exercise and Fatigue

    NARCIS (Netherlands)

    Ament, Wim; Verkerke, Gijsbertus J.

    2009-01-01

    Physical exercise affects the equilibrium of the internal environment. During exercise the contracting muscles generate force or power and heat. So physical exercise is in fact a form of mechanical energy. This generated energy will deplete the energy stocks within the body. During exercise,

  12. Exercise in a child with systemic lupus erythematosus and antiphospholipid syndrome.

    Science.gov (United States)

    Prado, Danilo M; Gualano, Bruno; Pinto, Ana Lúcia S; Sallum, Adriana M; Perondi, Maria B; Roschel, Hamilton; Silva, Clovis Artur

    2011-12-01

    Exercise training has emerged as a potential therapeutic strategy to counteract the decline in physical function and aerobic capacity in pediatric rheumatic disease. We report for the first time on the effects of exercise training in juvenile systemic lupus erythematosus (JSLE) and antiphospholipid syndrome (APS). A 15-yr-old boy with JSLE and APS treated with warfarin, azathioprine, and prednisone underwent a 12-wk aerobic exercise training program to improve his physical capacity and functioning. Before and after the 12-wk exercise program, the patient was submitted to incremental cardiopulmonary tests to determine VO(2peak), peak and submaximal exercise intensity, and time to exhaustion. In addition, a 6-min square-wave test was performed for assessing metabolic parameters. Functioning was assessed by using the visual analog scale. Laboratory parameters of inflammation were also assessed at baseline and 48 h after the last training session. All the cardiopulmonary parameters (e.g., VO(2max) = +36.0%, time to exhaustion = +67.8%, peak exercise intensity = +16.7%) and the metabolic cost of movement (e.g., energy expenditure = -28.3% to -33.3%, VO(2) = -29.3% to -33.4%) were improved. Both disease activity and cumulative damage scores did not change after the intervention, and no evidence of exercise-induced exacerbation of inflammation was observed. Visual analog scale scores were also improved according to the patients' evaluation (before intervention = 8 vs after intervention = 10), parents' evaluation (before intervention = 8 vs after intervention = 10), and physicians' evaluation (before intervention = 6 vs after intervention = 9). This is the first evidence that a 12-wk supervised aerobic training program can be safe and effective in improving aerobic conditioning and physical function in a patient with JSLE and APS. In light of these findings, the therapeutic effects of exercise training in pediatric rheumatic diseases merit further investigations.

  13. Mitochondrial efficiency and exercise economy following heat stress: a potential role of uncoupling protein 3.

    Science.gov (United States)

    Salgado, Roy M; Sheard, Ailish C; Vaughan, Roger A; Parker, Daryl L; Schneider, Suzanne M; Kenefick, Robert W; McCormick, James J; Gannon, Nicholas P; Van Dusseldorp, Trisha A; Kravitz, Len R; Mermier, Christine M

    2017-02-01

    Heat stress has been reported to reduce uncoupling proteins (UCP) expression, which in turn should improve mitochondrial efficiency. Such an improvement in efficiency may translate to the systemic level as greater exercise economy. However, neither the heat-induced improvement in mitochondrial efficiency (due to decrease in UCP), nor its potential to improve economy has been studied. Determine: (i) if heat stress in vitro lowers UCP3 thereby improving mitochondrial efficiency in C2C12 myocytes; (ii) whether heat acclimation (HA) in vivo improves exercise economy in trained individuals; and (iii) the potential improved economy during exercise at altitude. In vitro, myocytes were heat stressed for 24 h (40°C), followed by measurements of UCP3, mitochondrial uncoupling, and efficiency. In vivo, eight trained males completed: (i) pre-HA testing; (ii) 10 days of HA (40°C, 20% RH); and (iii) post-HA testing. Pre- and posttesting consisted of maximal exercise test and submaximal exercise at two intensities to assess exercise economy at 1600 m (Albuquerque, NM) and 4350 m. Heat-stressed myocytes displayed significantly reduced UCP3 mRNA expression and, mitochondrial uncoupling (77.1 ± 1.2%, P economy did not change at low and moderate exercise intensities. Our findings indicate that while heat-induced reduction in UCP3 improves mitochondrial efficiency in vitro, this is not translated to in vivo improvement of exercise economy at 1600 m or 4350 m. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  14. Orbital Fitness: An Overview of Space Shuttle Cardiopulmonary Exercise Physiology Findings

    Science.gov (United States)

    Moore, Alan D.

    2011-01-01

    Limited observations regarding the cardiopulmonary responses to aerobic exercise had been conducted during short-duration spaceflight before the Space Shuttle program. This presentation focuses on the findings regarding changes observed in the cardiopulmonary exercise responses during and following Shuttle flights. During flight, maximum oxygen uptake (VO2max) remained unchanged as did the maximum work rate achievable during cycle exercise testing conducted during the last full flight day. Immediately following flight, the ubiquitous finding, confirmed by investigations conducted during the Spacelab Life Sciences missions 1 and 2 and by NASA Detailed Supplemental Objective studies, indicated that VO2max was reduced; however, the reduction in VO2max was transient and returned to preflight levels within 7 days following return. Studies regarding the influence of aerobic exercise countermeasures performed during flight on postflight performance were mostly limited to the examination of the heart rate (HR) response to submaximal exercise testing on landing day. These studies revealed that exercise HR was elevated in individuals who performed little to no exercise during their missions as compared to individuals who performed regular exercise. In addition, astronauts who performed little to no aerobic exercise during flight demonstrated an increased HR and lowered pulse pressure response to the standard stand test on landing day, indicating a decrease in orthostatic function in these individuals. With regard to exercise modality, four devices were examined during the Shuttle era: two treadmills, a cycle ergometer, and a rowing device. Although there were limited investigations regarding the use of these devices for exercise training aboard the Shuttle, there was no clear consensus reached regarding which proved to be a "superior" device. Each device had a unique operational or physiologic limitation associated with its use. In conclusion, exercise research conducted

  15. Exercise thermoregulation in men after 1 and 24-hours of 6 degrees head-down tilt

    Science.gov (United States)

    Ertl, A. C.; Dearborn, A. S.; Weidhofer, A. R.; Bernauer, E. M.; Greenleaf, J. E.

    2000-01-01

    BACKGROUND: Exercise thermoregulation is dependent on heat loss by increased skin blood flow (convective and conductive heat loss) and through enhanced sweating (evaporative heat loss). Reduction of plasma volume (PV), increased plasma osmolality, physical deconditioning, and duration of exposure to simulated and actual microgravity reduces the ability to thermoregulate during exercise. HYPOTHESIS: We hypothesized that 24 h of head down tilt (HDT24) would alter thermoregulatory responses to a submaximal exercise test and result in a higher exercise rectal temperature (Tre) when compared with exercise Tre after 1 h of head down tilt (HDT1). METHODS: Seven men (31+/-SD 6 yr, peak oxygen uptake (VpO2peak) of 44+/-6 ml x kg(-1) x min(-1)) were studied during 70 min of supine cycling at 58+/-SE 1.5% VO2peak at 22.0 degrees C Tdb and 47% rh. RESULTS: Relative to pre-tilt sitting chair rest data, HDT1 resulted in a 6.1+/-0.9% increase and HDT24 in a 4.3+/-2.3% decrease in PV (delta = 10.4% between experiments, p<0.05) while plasma osmolality remained unchanged (NS). Pre-exercise Tre was elevated after HDT24 (36.71 degrees C +/-0.06 HDT1 vs. 36.93 degrees C+/-0.11 HDT24, p<0.05). The 70 min of exercise did not alter this relationship (p<0.05) with respective end exercise increases in Tre to 38.01 degrees C and 38.26 degrees C (degrees = 1.30 degrees C (HDT1) and 1.33 degrees C (HDT24)). While there were no pre-exercise differences in mean skin temperature (Tsk), a significant (p<0.05) time x treatment interaction occurred during exercise: after min 30 in HDT24 the Tsk leveled off at 31.1 degrees C, while it continued to increase reaching 31.5 degrees C at min 70 in HDT1. A similar response (NS) occurred in skin blood velocity. Neither local sweating rates nor changes in body weight during exercise of -1.63+/-0.24 kg (HDT1) or - 1.33+/-0.09 kg (HDT24) were different (NS) between experiments. CONCLUSION: While HDT24 resulted in elevated pre-exercise Tre, reduced PV

  16. DHEA, physical exercise and doping.

    Science.gov (United States)

    Collomp, K; Buisson, C; Lasne, F; Collomp, R

    2015-01-01

    The dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) concentrations during acute and chronic exercise (training) have been investigated only fairly recently. DHEA is generally preferred to DHEA-S for exploring the acute exercise repercussions in laboratory or field tests because of its shorter elimination half-life. Conversely, DHEA-S is preferred to estimate chronic adaptations. Both can be measured noninvasively in saliva, and it is therefore possible to follow these hormone responses in elite athletes during competitive events and in healthy and pathological populations, without imposing additional stress. Indeed, the correlation between saliva and serum concentrations is high for steroid hormones, both at rest and during exercise. In this review, we will first summarize the current knowledge on the DHEA/DHEA-S responses to exercise and examine the potential modulating factors: exercise intensity, gender, age, and training. We will then discuss the ergogenic effects that athletes expect from the exogenous administration of DHEA and the antidoping methods of analysis currently used to detect this abuse. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Design and testing of an MRI-compatible cycle ergometer for non-invasive cardiac assessments during exercise

    Directory of Open Access Journals (Sweden)

    Gusso Silmara

    2012-03-01

    Full Text Available Abstract Background Magnetic resonance imaging (MRI is an important tool for cardiac research, and it is frequently used for resting cardiac assessments. However, research into non-pharmacological stress cardiac evaluation is limited. Methods We aimed to design a portable and relatively inexpensive MRI cycle ergometer capable of continuously measuring pedalling workload while patients exercise to maintain target heart rates. Results We constructed and tested an MRI-compatible cycle ergometer for a 1.5 T MRI scanner. Resting and sub-maximal exercise images (at 110 beats per minute were successfully obtained in 8 healthy adults. Conclusions The MRI-compatible cycle ergometer constructed by our research group enabled cardiac assessments at fixed heart rates, while continuously recording power output by directly measuring pedal force and crank rotation.

  18. Effects of 3-day bed rest on physiological responses to graded exercise in athletes and sedentary men

    Science.gov (United States)

    Smorawinski, J.; Nazar, K.; Kaciuba-Uscilko, H.; Kaminska, E.; Cybulski, G.; Kodrzycka, A.; Bicz, B.; Greenleaf, J. E.

    2001-01-01

    To test the hypotheses that short-term bed-rest (BR) deconditioning influences metabolic, cardiorespiratory, and neurohormonal responses to exercise and that these effects depend on the subjects' training status, 12 sedentary men and 10 endurance- and 10 strength-trained athletes were submitted to 3-day BR. Before and after BR they performed incremental exercise test until volitional exhaustion. Respiratory gas exchange and heart rate (HR) were recorded continuously, and stroke volume (SV) was measured at submaximal loads. Blood was taken for lactate concentration ([LA]), epinephrine concentration ([Epi]), norepinephrine concentration ([NE]), plasma renin activity (PRA), human growth hormone concentration ([hGH]), testosterone, and cortisol determination. Reduction of peak oxygen uptake (VO(2 peak)) after BR was greater in the endurance athletes than in the remaining groups (17 vs. 10%). Decrements in VO(2 peak) correlated positively with the initial values (r = 0.73, P physical training, being the most pronounced in the endurance athletes.

  19. One year of high-intensity interval training improves exercise capacity, but not left ventricular function in stable heart transplant recipients: a randomised controlled trial.

    Science.gov (United States)

    Rustad, Lene A; Nytrøen, Kari; Amundsen, Brage H; Gullestad, Lars; Aakhus, Svend

    2014-02-01

    Heart transplant recipients have lower exercise capacity and impaired cardiac function compared with the normal population. High-intensity interval training (HIIT) improves exercise capacity and cardiac function in patients with heart failure and hypertension, but the effect on cardiac function in stable heart transplant recipients is not known. Thus, we investigated whether HIIT improved cardiac function and exercise capacity in stable heart transplant recipients by use of comprehensive rest- and exercise-echocardiography and cardiopulmonary exercise testing. Fifty-two clinically stable heart transplant recipients were randomised either to HIIT (4 × 4 minutes at 85-95% of peak heart rate three times per week for eight weeks) or to control. Three such eight-week periods were distributed throughout one year. Echocardiography (rest and submaximal exercise) and cardiopulmonary exercise testing were performed at baseline and follow-up. One year of HIIT increased VO 2peak from 27.7 ± 5.5 at baseline to 30.9 ± 5.0 ml/kg/min at follow-up, while the control group remained unchanged (28.5 ± 7.0 vs. 28.0 ± 6.7 ml/kg per min, p cardiac systolic and diastolic function significantly. Thus, the observed augmentation in exercise capacity is best explained by extra-cardiac adaptive mechanisms.

  20. The Effect of Acute Rhodiola rosea Ingestion on Exercise Heart Rate, Substrate Utilisation, Mood State, and Perceptions of Exertion, Arousal, and Pleasure/Displeasure in Active Men

    Science.gov (United States)

    Clarke, Neil D.

    2014-01-01

    The aim of this study was to examine the effect of acute Rhodiola rosea (R. rosea) ingestion on substrate utilisation, mood state, RPE, and exercise affect. Ten males (mean age ± S.D. = 26 ± 6 years) completed two 30-minute cycling trials at an intensity of 70% of V˙O2max⁡ following ingestion of either 3 mg·kg−1 body mass of R. rosea or placebo using a double-blind, crossover design. During exercise, heart rate and RPE were recorded. Participants completed measures of mood state and exercise affect before and after exercise. Expired air samples were taken during exercise to determine substrate utilisation. Repeated measures analysis of variance indicated that RPE was significantly lower at 30 minutes into exercise versus placebo (P = 0.003). Perceptions of arousal (P = 0.05) and pleasure were significantly higher after exercise with R. rosea compared to placebo (P = 0.003). Mood state scores for vigor were also higher in R. rosea condition compared to placebo (P = 0.008). There were no significant differences in energy expenditure, carbohydrate, or fat oxidation between conditions (P > 0.05). Ingestion of R. rosea favourably influenced RPE and exercise affect without changes in energy expenditure or substrate utilization during 30-minute submaximal cycling performance. PMID:26464892

  1. The Effect of Acute Rhodiola rosea Ingestion on Exercise Heart Rate, Substrate Utilisation, Mood State, and Perceptions of Exertion, Arousal, and Pleasure/Displeasure in Active Men

    Directory of Open Access Journals (Sweden)

    Michael J. Duncan

    2014-01-01

    Full Text Available The aim of this study was to examine the effect of acute Rhodiola rosea (R. rosea ingestion on substrate utilisation, mood state, RPE, and exercise affect. Ten males (mean age ± S.D. = 26 ± 6 years completed two 30-minute cycling trials at an intensity of 70% of V˙O2max⁡ following ingestion of either 3 mg·kg−1 body mass of R. rosea or placebo using a double-blind, crossover design. During exercise, heart rate and RPE were recorded. Participants completed measures of mood state and exercise affect before and after exercise. Expired air samples were taken during exercise to determine substrate utilisation. Repeated measures analysis of variance indicated that RPE was significantly lower at 30 minutes into exercise versus placebo (P=0.003. Perceptions of arousal (P=0.05 and pleasure were significantly higher after exercise with R. rosea compared to placebo (P=0.003. Mood state scores for vigor were also higher in R. rosea condition compared to placebo (P=0.008. There were no significant differences in energy expenditure, carbohydrate, or fat oxidation between conditions (P>0.05. Ingestion of R. rosea favourably influenced RPE and exercise affect without changes in energy expenditure or substrate utilization during 30-minute submaximal cycling performance.

  2. The Effect of Acute Exercise on Serum Vaspin Level and Its Relation to Insulin Sensitivity in Overweight Elderly Men

    Directory of Open Access Journals (Sweden)

    Jabbar Bashiri

    2014-08-01

    Full Text Available Background: Vaspin is a new discovered adipocytokine which is a member of serine protease inhibitor family secreted from adipose tissue and might play a role in insulin sensitivity. The purpose of this study was to investigate the effect of acute exercise on serum vaspin levels and its relation to insulin sensitivity in overweight elderly men. Materials and Methods: In this semi-experimental study, 12 healthy elderly men volunteers randomly selected and performed one session aerobic exercise including 30 minutes of cycling at 70-75% of HRmax, which was followed by 30 minutes of recovery. Three blood samples were taken before exercise, immediately after exercise and after 30 minutes of recovery. Data were analyzed by repeated measure ANOVA and Bonferroni test and Pearson’s correlations were performed to identify possible relationship among the assessed variables. Statistical significance was set at p≤0.05. Results: There were no significant differences for vaspin across time. Insulin and glucose concentration and insulin resistance decreased immediately after exercise. However insulin concentration and insulin resistance returned to pre-exercise level at the end of recovery. Furthermore, no significant correlations were observed among the variables assessed except for the expected between insulin level and insulin resistance. Conclusion: These results indicate that a sub-maximal aerobic workout does not result in significant changes in vaspin levels in elderly men. Furthermore, we observed that vaspin is not associated with insulin sensitivity in this study.

  3. Graduated exercise training and progressive resistance training in adolescents with chronic fatigue syndrome: a randomized controlled pilot study.

    Science.gov (United States)

    Gordon, Brett A; Knapman, Leona M; Lubitz, Lionel

    2010-12-01

    to investigate the differential effects of aerobic graded exercise and progressive resistance training on exercise tolerance, fatigue and quality of life in adolescent patients with chronic fatigue syndrome (CFS). single-blind, randomized controlled pilot trial. a major metropolitan hospital in Melbourne, Australia. twenty-two adolescents aged 13-18 years diagnosed with CFS and admitted to the inpatient chronic fatigue rehabilitation programme. patients were randomized to either graded aerobic exercise training or a progressive resistance training programme, for five days/week for four weeks. The graded aerobic training consisted of 20-40 minutes of stationary cycling and treadmill exercise. The progressive resistance training involved 16 exercises performed with single set, moderate load and high repetitions. exercise tolerance (time to fatigue) measured on a graded sub-maximal treadmill test, metabolic equivalents and quality of life, along with muscular strength (maximium push-ups) and endurance (sit-to-stand) and questionnaires evaluating depressive symptoms and fatigue severity. no intervention was significantly better than the other for any outcome. However, physical capacity and quality of life significantly improved in both groups, while fatigue severity and symptoms of depression improved only with aerobic training. resistance and aerobic training resulted in similar changes to physical capacity, quality of life and fatigue severity. Generally, patients who completed resistance training or aerobic training experienced significant improvements in outcomes from baseline when they entered the programme. Whether these improvements can be attributed to the treatment is unknown.

  4. Sub-maximal and maximal Yo-Yo intermittent endurance test level 2: heart rate response, reproducibility and application to elite soccer

    DEFF Research Database (Denmark)

    Bradley, Paul S; Mohr, Magni; Bendiksen, Mads

    2011-01-01

    The aims of this study were to (1) determine the reproducibility of sub-maximal and maximal versions of the Yo-Yo intermittent endurance test level 2 (Yo-Yo IE2 test), (2) assess the relationship between the Yo-Yo IE2 test and match performance and (3) quantify the sensitivity of the Yo-Yo IE2 te......) in Yo-Yo IE2 test performance and heart rate after 6 min were 3.9% (n = 37) and 1.4% (n = 32), respectively. Elite male senior and youth U19 players Yo-Yo IE2 performances were better (P ...

  5. Field theory

    CERN Document Server

    Roman, Steven

    2006-01-01

    Intended for graduate courses or for independent study, this book presents the basic theory of fields. The first part begins with a discussion of polynomials over a ring, the division algorithm, irreducibility, field extensions, and embeddings. The second part is devoted to Galois theory. The third part of the book treats the theory of binomials. The book concludes with a chapter on families of binomials - the Kummer theory. This new edition has been completely rewritten in order to improve the pedagogy and to make the text more accessible to graduate students.  The exercises have also been im

  6. Measuring submaximal performance parameters to monitor fatigue and predict cycling performance: a case study of a world-class cyclo-cross cyclist.

    Science.gov (United States)

    Lamberts, Robert P; Rietjens, Gerard J; Tijdink, Hendrik H; Noakes, Timothy D; Lambert, Michael I

    2010-01-01

    Recently a novel submaximal test, known as the Lamberts and Lambert submaximal cycle test (LSCT), has been developed with the purpose of monitoring and predicting changes in cycling performance. Although this test has been shown to be reliable and able to predict cycling performance, it is not known whether it can measure changes in training status. Therefore, the aim of this study was to determine whether the LSCT is able to track changes in performance parameters, and objective and subjective markers of well-being. A world class cyclo-cross athlete (31 years) volunteered to participate in a 10-week observational study. Before and after the study, a peak power output (PPO) test with respiratory gas analysis (VO(2max)) and a 40-km time trial (40-km TT) test were performed. Training data were recorded in a training logbook with a daily assessment of well-being, while a weekly LSCT was performed. After the training period all performance parameters had improved by a meaningful amount (PPO +5.2%; 40-km TT time -2.5%; VO(2max) +1.4%). Increased training loads during weeks 2 and 6 and the subsequent training-induced fatigue was reflected in the increased well-being scores. Changes during the LSCT were most clearly notable in (1) increased power during the first minute of third stage, (2) increased rating of perceived exertion during second and third stages, and (3) a faster heart rate recovery after the third stage. In conclusion, these data suggest that the LSCT is able to track changes in training status and detect the consequences of sharp increases in training loads which seem to be associated with accumulating fatigue.

  7. Aerobic exercise training for adults with fibromyalgia.

    Science.gov (United States)

    Bidonde, Julia; Busch, Angela J; Schachter, Candice L; Overend, Tom J; Kim, Soo Y; Góes, Suelen M; Boden, Catherine; Foulds, Heather Ja

    2017-06-21

    Exercise training is commonly recommended for individuals with fibromyalgia. This review is one of a series of reviews about exercise training for people with fibromyalgia that will replace the "Exercise for treating fibromyalgia syndrome" review first published in 2002. • To evaluate the benefits and harms of aerobic exercise training for adults with fibromyalgia• To assess the following specific comparisons ० Aerobic versus control conditions (eg, treatment as usual, wait list control, physical activity as usual) ० Aerobic versus aerobic interventions (eg, running vs brisk walking) ० Aerobic versus non-exercise interventions (eg, medications, education) We did not assess specific comparisons involving aerobic exercise versus other exercise interventions (eg, resistance exercise, aquatic exercise, flexibility exercise, mixed exercise). Other systematic reviews have examined or will examine these comparisons (Bidonde 2014; Busch 2013). We searched the Cochrane Library, MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Physiotherapy Evidence Database (PEDro), Thesis and Dissertation Abstracts, the Allied and Complementary Medicine Database (AMED), the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), and the ClinicalTrials.gov registry up to June 2016, unrestricted by language, and we reviewed the reference lists of retrieved trials to identify potentially relevant trials. We included randomized controlled trials (RCTs) in adults with a diagnosis of fibromyalgia that compared aerobic training interventions (dynamic physical activity that increases breathing and heart rate to submaximal levels for a prolonged period) versus no exercise or another intervention. Major outcomes were health-related quality of life (HRQL), pain intensity, stiffness, fatigue, physical function, withdrawals, and adverse events. Two review authors independently selected trials for inclusion, extracted

  8. Calf muscle oxygen saturation and the effects of supervised exercise training for intermittent claudication.

    Science.gov (United States)

    Beckitt, Tim A; Day, Jude; Morgan, Maria; Lamont, Peter M

    2012-08-01

    The mechanisms underlying the symptomatic improvement witnessed as a result of exercise training in intermittent claudication remain unclear. There is no reproducible evidence to support increased limb blood flow resulting from neovascularization. Changes in oxygenation of active muscles as a result of blood redistribution are hypothesized but unproven. This study sought evidence of improved gastrocnemius oxygenation resulting from exercise training. The study recruited 42 individuals with claudication. After an initial control period of exercise advice, participants undertook a 3-month supervised exercise program. Spatially resolved near-infrared spectroscopy monitored calf muscle oxygen saturation (Sto(2)) during exercise and after a period of cuff-induced ischemia. Comparison was made with 14 individuals undergoing angioplasty for calf claudication. Clinical outcomes of claudication distance and maximum walking distance were measured by treadmill assessment. Significant increases occurred in mean [interquartile range] claudication disease (57 [38-78] to 119 [97-142] meters; P = .01) and maximum walking distance (124 [102-147] to 241 [193-265] meters; P = .02) after supervised exercise but not after the control period. No change occurred in resting Sto(2) at any interval. Angioplasty (27% [21-34] to 19% [13-29]; P = .02) but not exercise training (26% [21-32] vs 23% [20-31]; P > .20) resulted in a reduced Sto(2) desaturation in response to submaximal exercise and an increased hyperemic hemoglobin oxygen recovery rate after ischemia (0.48 [0.39-0.55] to 0.63 [0.52-0.69] s(-1); P = .01). However supervised exercise reduced the Sto(2) recovery half-time by 17% (82 [64-101] to 68 [55-89] seconds; P = .02). Supervised exercise training is not associated with increased gastrocnemius muscle oxygenation during exercise or increased hyperemic hemoglobin flow after a model of ischemia. This suggests that the symptomatic improvement witnessed is not the result of increased

  9. The effect of sports specialization on musculus quadriceps function after exercise-induced muscle damage.

    Science.gov (United States)

    Skurvydas, Albertas; Brazaitis, Marius; Venckūnas, Tomas; Kamandulis, Sigitas; Stanislovaitis, Aleksas; Zuoza, Aurelijus

    2011-12-01

    The primary aim of the present study was to examine the effect of eccentric exercise-induced (100 submaximal eccentric contractions at an angular velocity of 60° s⁻¹, with 20-s rest intervals) muscle damage on peripheral and central fatigue of quadriceps muscle in well-trained long-distance runners, sprint runners, volleyball players, and untrained subjects. We found that (i) indirect symptoms of exercise-induced muscle damage (prolonged decrease in maximal voluntary contraction, isokinetic concentric torque, and electrically induced (20 Hz) torque) were most evident in untrained subjects, while there were no significant differences in changes of muscle soreness and plasma creatine kinase 48 h after eccentric exercise between athletes and untrained subjects; (ii) low-frequency fatigue was greater in untrained subjects and volleyball players than in sprint runners and long-distance runners; (iii) in all subjects, electrically induced (100 Hz) torque decreased significantly by about 20%, while central activation ratio decreased significantly by about 8% in untrained subjects and sprint runners, and by about 3%-5% in long-distance runners and volleyball players. Thus, trained subjects showed greater resistance to exercise-induced muscle damage for most markers, and long-distance runners had no advantage over sprint runners or volleyball players.

  10. 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, Pexercise-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.

  11. Enhanced muscular oxygen extraction in athletes exaggerates hypoxemia during exercise in hypoxia.

    Science.gov (United States)

    Van Thienen, Ruud; Hespel, Peter

    2016-02-01

    High rate of muscular oxygen utilization facilitates the development of hypoxemia during exercise at altitude. Because endurance training stimulates oxygen extraction capacity, we investigated whether endurance athletes are at higher risk to developing hypoxemia and thereby acute mountain sickness symptoms during exercise at simulated high altitude. Elite athletes (ATL; n = 8) and fit controls (CON; n = 7) cycled for 20 min at 100 W (EX100W), as well as performed an incremental maximal oxygen consumption test (EXMAX) in normobaric hypoxia (0.107 inspired O2 fraction) or normoxia (0.209 inspired O2 fraction). Cardiorespiratory responses, arterial Po2 (PaO2), and oxygenation status in m. vastus lateralis [tissue oxygenation index (TOIM)] and frontal cortex (TOIC) by near-infrared spectroscopy, were measured. Muscle O2 uptake rate was estimated from change in oxyhemoglobin concentration during a 10-min arterial occlusion in m. gastrocnemius. Maximal oxygen consumption in normoxia was 70 ± 2 ml·min(-1·)kg(-1) in ATL vs. 43 ± 2 ml·min(-1·)kg(-1) in CON, and in hypoxia decreased more in ATL (-41%) than in CON (-25%, P hypoxemia during submaximal exercise in hypoxia in endurance-trained individuals. This effect may predispose to premature development of acute mountain sickness symptoms during exercise at altitude. Copyright © 2016 the American Physiological Society.

  12. Effect of Physical Exercise on the Cardiorespiratory Response in Overweight Adolescents

    Directory of Open Access Journals (Sweden)

    Diego A S Silva

    2012-03-01

    Full Text Available Purpose: To evaluate the effects of an aerobic physical exercise program on the metabolic and cardiorespiratory response in overweight adolescents.Material and Method: This is a randomized study evaluating overweight adolescents divided into intervention and control groups before and after an aerobic exercise program. Pre- and post-intervention aerobic fitness was evaluated by a submaximal incremental test on a cycle ergometer. The training program lasted 12 weeks, when the intervention group exercised three times per week on a cycle ergometer at individual training intensities corresponding to lactate threshold (LT and onset of blood lactate accumulation (OBLA. The individual workload was increased by 10% at 2-week intervals.Results: After intervention, an increase in workload levels corresponding to LT (33.3% and OBLA (14.2% was observed in the intervention group. In addition, the intervention group reached LT training intensity at a heart rate higher than that observed before intervention and that of controls (p<0.05. Discussion: The program resulted in positive changes in aerobic fitness and heart rate, improving exercise tolerance. Turk Jem 2012; 16: 14-8

  13. Exercise in Pregnancy.

    Science.gov (United States)

    Gregg, Vanessa H; Ferguson, James E

    2017-10-01

    Routine exercise should be recommended to healthy pregnant women after consultation with an obstetric provider. Even pregnant women who have not been exercising regularly can gradually increase their exercise during pregnancy. Regular exercise during pregnancy promotes overall wellness and helps maintain appropriate gestational weight gain and appropriate fetal weight gain. Exercise in pregnancy may also reduce hypertensive disorders of pregnancy and gestational diabetes, and may be associated with shorter first stage of labor and decreased risk for cesarean section. Exercise in pregnancy is safe for pregnant women and their fetuses and can have multiple health benefits. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Effect of exhaustive exercise on the angular pedaling pattern: A preliminary study

    Directory of Open Access Journals (Sweden)

    Matheus Joner Wiest

    2009-01-01

    Full Text Available http://dx.doi.org/10.5007/1980-0037.2009v11n4p386   Considering biomechanical aspects such as kinematics, fatigue can be characterized as a loss of efficiency in maintaining a movement pattern, such as pedaling technique, during exercise. The objective of this preliminary study was to investigate the effects of 1-h exhaustive cycling exercise at intensity of 80% VO2max on pedaling technique. The pedaling technique was evaluated in four skilled mountain-bike cyclists by 2D kinematics. The main hypothesis of this study was that angular changes in response to fatigue would occur mainly in the ankle joint. After achievement of maximal oxygen uptake (VO2max, the cyclists were submitted to a submaximal protocol at intensity corresponding to 80% VO2max for 1 h. The cyclists were filmed throughout 10 complete consecutive crank cycles at intervals of 10 min. Images were acquired from the right lower limb and the hip, knee and ankle joint angles were measured after kinematic processing. The Shapiro-Wilk test, ANOVA and post-hoc Tukey HSD test were used for statistical analysis, with the level of significance set at 0.05. Statistical analysis showed a significant difference only for ankle kinematics after 40 min of exercise, with an increase in the range of motion from 20° at the beginning of exercise to 35° at the end of exercise. This result confirms the hypothesis proposed and suggests that only the ankle joint was affected by the exercise. The characteristics of ankle movement suggest that this joint plays a compensatory role in an attempt to maintain the pedaling technique and to sustain the exercise workload.

  15. Cardiopulmonary exercise testing in small abdominal aortic aneurysm: profile, safety, and mortality estimates.

    Science.gov (United States)

    Myers, Jonathan; Powell, Alyssa; Smith, Kimberly; Fonda, Holly; Dalman, Ronald L

    2011-06-01

    Few data are available regarding exercise testing in patients with abdominal aortic aneurysm (AAA) disease. The purpose of this study was to evaluate safety and to characterize the hemodynamic and cardiopulmonary (CPX) response to exercise in a large group of patients with AAA. Three hundred and six patients with AAA ≥3.0 to ≤5.0 cm (mean 72 ± 8 years) underwent CPX as part of a randomized trial of exercise training. CPX and hemodynamic responses, ischemic events, rhythm disturbances, and risk estimates based on treadmill scores were quantified and compared to an age-matched group of 2155 veterans referred for exercise testing for clinical reasons. Peak VO(2) was similar between patients with AAA and the referral group (20.0 ± 6 ml/kg/min; 77 percent of age-predicted and 20.3 ± 7 ml/kg/min; 80 percent of age-predicted, respectively). The incidence of exercise-induced hypotension and hypertension was higher in AAA patients versus the referral group (2.9 and 3.6 percent vs mortality, respectively, were similar between groups. Patients with AAA have a slightly higher incidence of hyper- and hypotensive responses to exercise than age-matched referrals, but no serious events related to CPX occurred. AAA patients can undergo maximal CPX safely and have risk scores based on treadmill test results that are similar to age-matched referral subjects. These findings extend recent studies using sub-maximal evaluations to stratify risk in patients considered for surgery, and support the routine use of exercise testing for risk evaluation and the functional assessment of patients with AAA.

  16. Effect of exhaustive exercise on the angular pedaling pattern: A preliminary study

    Directory of Open Access Journals (Sweden)

    Matheus Joner Wiest

    2009-09-01

    Full Text Available Considering biomechanical aspects such as kinematics, fatigue can be characterized as a loss of efficiency in maintaining a movement pattern, such as pedaling technique, during exercise. The objective of this preliminary study was to investigate the effects of 1-h exhaustive cycling exercise at intensity of 80% VO2max on pedaling technique. The pedaling technique was evaluated in four skilled mountain-bike cyclists by 2D kinematics. The main hypothesis of this study was that angular changes in response to fatigue would occur mainly in the ankle joint. After achievement of maximal oxygen uptake (VO2max, the cyclists were submitted to a submaximal protocol at intensity corresponding to 80% VO2max for 1 h. The cyclists were filmed throughout 10 complete consecutive crank cycles at intervals of 10 min. Images were acquired from the right lower limb and the hip, knee and ankle joint angles were measured after kinematic processing. The Shapiro-Wilk test, ANOVA and post-hoc Tukey HSD test were used for statistical analysis, with the level of significance set at 0.05. Statistical analysis showed a significant difference only for ankle kinematics after 40 min of exercise, with an increase in the range of motion from 20° at the beginning of exercise to 35° at the end of exercise. This result confirms the hypothesis proposed and suggests that only the ankle joint was affected by the exercise. The characteristics of ankle movement suggest that this joint plays a compensatory role in an attempt to maintain the pedaling technique and to sustain the exercise workload.

  17. Time to adapt exercise training regimens in pulmonary rehabilitation – a review of the literature

    Directory of Open Access Journals (Sweden)

    Lee AL

    2014-11-01

    Full Text Available Annemarie L Lee,1–4 Anne E Holland1–3 1Physiotherapy, Alfred Health, Melbourne, VIC, Australia; 2Institute for Breathing and Sleep, Austin Health, Melbourne, VIC, Australia; 3Physiotherapy, La Trobe University, Melbourne, VIC, Australia; 4Westpark Healthcare Centre, ON, Canada Abstract: Exercise intolerance, exertional dyspnea, reduced health-related quality of life, and acute exacerbations are features characteristic of chronic obstructive pulmonary disease (COPD. Patients with a primary diagnosis of COPD often report comorbidities and other secondary manifestations, which diversifies the clinical presentation. Pulmonary rehabilitation that includes whole body exercise training is a critical part of management, and core programs involve endurance and resistance training for the upper and lower limbs. Improvement in maximal and submaximal exercise capacity, dyspnea, fatigue, health-related quality of life, and psychological symptoms are outcomes associated with exercise training in pulmonary rehabilitation, irrespective of the clinical state in which it is commenced. There may be benefits for the health care system as well as the individual patient, with fewer exacerbations and subsequent hospitalization reported with exercise training. The varying clinical profile of COPD may direct the need for modification to traditional training strategies for some patients. Interval training, one-legged cycling (partitioning and non-linear periodized training appear to be equally or more effective than continuous training. Inspiratory muscle training may have a role as an adjunct to whole body training in selected patients. The benefits of balance training are also emerging. Strategies to ensure that health enhancing behaviors are adopted and maintained are essential. These may include training for an extended duration, alternative environments to undertake the initial program, maintenance programs following initial exercise training, program repetition

  18. Influence of intermittent hypoxic training on muscle energetics and exercise tolerance.

    Science.gov (United States)

    Holliss, Ben A; Fulford, Jonathan; Vanhatalo, Anni; Pedlar, Charles R; Jones, Andrew M

    2013-03-01

    Intermittent hypoxic training (IHT) is sometimes used by athletes to enhance nonhematological physiological adaptations to simulated altitude. We investigated whether IHT would result in greater improvements in muscle energetics and exercise tolerance compared with work-matched intermittent normoxic training (INT). Nine physically active men completed 3 wk of intensive, single-leg knee-extensor exercise training. Each training session consisted of 25 min of IHT (FiO2 14.5 ± 0.1%) with the experimental leg and 25 min of INT with the alternate leg, which served as a control. Before and after the training intervention, subjects completed a test protocol consisting of a bout of submaximal constant-work-rate exercise, a 24-s high-intensity exercise bout to quantify the phosphocreatine recovery time constant ([PCr]-τ), and an incremental test to the limit of tolerance. The tests were completed in normoxia and hypoxia in both INT and IHT legs. Muscle metabolism was assessed noninvasively using (31)P-magnetic resonance spectroscopy. Improvements in the time-to-exhaustion during incremental exercise were not significantly different between training conditions either in normoxia (INT, 28 ± 20% vs. IHT, 25 ± 9%; P = 0.86) or hypoxia (INT, 21 ± 10% vs. IHT, 15 ± 11%; P = 0.29). In hypoxia, [PCr]-τ was speeded slightly but significantly more post-IHT compared with post-INT (-7.3 ± 2.9 s vs. -3.7 ± 1.7 s; P < 0.01), but changes in muscle metabolite concentrations during exercise were essentially not different between IHT and INT. Under the conditions of this investigation, IHT does not appreciably alter muscle metabolic responses or incremental exercise performance compared with INT.

  19. Effect of abdominal binding on respiratory mechanics during exercise in athletes with cervical spinal cord injury.

    Science.gov (United States)

    West, Christopher R; Goosey-Tolfrey, Victoria L; Campbell, Ian G; Romer, Lee M

    2014-07-01

    We asked whether elastic binding of the abdomen influences respiratory mechanics during wheelchair propulsion in athletes with cervical spinal cord injury (SCI). Eight Paralympic wheelchair rugby players with motor-complete SCI (C5-C7) performed submaximal and maximal incremental exercise tests on a treadmill, both with and without abdominal binding. Measurements included pulmonary function, pressure-derived indices of respiratory mechanics, operating lung volumes, tidal flow-volume data, gas exchange, blood lactate, and symptoms. Residual volume and functional residual capacity were reduced with binding (77 ± 18 and 81 ± 11% of unbound, P respiratory mechanics with binding may benefit O2 transport capacity by an improvement in central circulatory function. Copyright © 2014 the American Physiological Society.

  20. Exercise-induced asthma

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000036.htm Exercise-induced asthma To use the sharing features on this page, ... such as running, basketball, or soccer. Use Your Asthma Medicine Before you Exercise Take your short-acting, ...