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Sample records for submaximal exercise intensities

  1. 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

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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.

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

    Science.gov (United States)

    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.

  10. 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.

  11. 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…

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

    Science.gov (United States)

    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.

  13. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  16. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  20. 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...

  1. 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.

  2. 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...

  3. 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.

  4. 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.

  5. 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.

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

    Science.gov (United States)

    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.

  7. 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

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. [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.

  13. 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.

  14. 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.

  15. 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

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

    Science.gov (United States)

    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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

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

    Science.gov (United States)

    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.

  2. 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.

  3. 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

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

    Directory of Open Access Journals (Sweden)

    Leng Xiaoyan

    2009-11-01

    Full Text Available Abstract Background Older heart failure (HF patients exhibit exercise intolerance during activities of daily living. We hypothesized that reduced lower extremity blood flow (LBF due to reduced forward cardiac output would contribute to submaximal exercise intolerance in older HF patients. Methods and Results Twelve HF patients both with preserved and reduced left ventricular ejection fraction (LVEF (aged 68 ± 10 years without large (aorta or medium sized (iliac or femoral artery vessel atherosclerosis, and 13 age and gender matched healthy volunteers underwent a sophisticated battery of assessments including a peak exercise oxygen consumption (peak VO2, b physical function, c cardiovascular magnetic resonance (CMR submaximal exercise measures of aortic and femoral arterial blood flow, and d determination of thigh muscle area. Peak VO2 was reduced in HF subjects (14 ± 3 ml/kg/min compared to healthy elderly subjects (20 ± 6 ml/kg/min (p = 0.01. Four-meter walk speed was 1.35 ± 0.24 m/sec in healthy elderly verses 0.98 ± 0.15 m/sec in HF subjects (p p ≤ 0.03. Conclusion During CMR submaximal bike exercise in the elderly with heart failure, mechanisms other than low cardiac output are responsible for reduced lower extremity blood flow.

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

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    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

  6. 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

  7. 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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

  11. 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.

  12. 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

    2016-03-01

    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.

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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).

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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 ...

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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...

  10. 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.

  11. 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)

  12. 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...

  13. 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...

  14. 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...

  15. 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.

  16. 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.

  17. 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.

  18. 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...

  19. 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.

  20. Exercise intensity and blood pressure during sleep.

    Science.gov (United States)

    Jones, H; George, K; Edwards, B; Atkinson, G

    2009-02-01

    Exercise, of appropriate intensity and duration, could help maintain normotension if post-exercise hypotension persists over subsequent everyday activities. Therefore, we monitored ambulatory blood pressure (BP) for 24 h following four separate exercise bouts which differed in intensity, duration and total work completed. At 08:00 h, six normotensive males completed a no exercise control and, in two further trials, 30 min of cycling at 70 % V O (2 peak) and 40 % V O (2 peak). A fourth trial involved cycling at 40 % V O (2 peak) for a time which equated total work with that in the most intense exercise trial. Between 20 min and 24 h after exercise, ambulatory BP, heart rate (HR) and wrist-activity were compared between trials using general linear models. Participants slept normally at night. Post-exercise changes in BP and HR were not affected by exercise intensity or total work completed from 20 min after exercise until nocturnal sleep-onset (p > 0.21). During sleep, mean arterial BP was lower following exercise at 70 % V O (2 peak) compared to the other trials (p = 0.03), including the 40 % V O (2 peak) trial equated for total work (90 % CI for difference = - 22.1 to - 0.1). We conclude that daytime exercise can elicit a physiologically meaningful lower BP during sleep and exercise intensity is the most important factor in this phenomenon.

  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

    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

  2. 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.

  3. 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

  4. 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

  5. High Intensity Exercise in Multiple Sclerosis

    DEFF Research Database (Denmark)

    Wens, Inez; Dalgas, Ulrik; Vandenabeele, Frank

    2015-01-01

    exercise groups that performed 12 weeks of a high intensity interval (HITR, n = 12) or high intensity continuous cardiovascular training (HCTR, n = 11), both in combination with resistance training. M.vastus lateralis fiber cross sectional area (CSA) and proportion, knee-flexor/extensor strength, body......±5%) and lean tissue mass (+1.4±0.5%) only increased in HITR. Finally self-reported physical activity levels increased 73±19% and 86±27% in HCTR and HITR, respectively. Conclusion High intensity cardiovascular exercise combined with resistance training was safe, well tolerated and improved muscle contractile......Introduction Low-to-moderate intensity exercise improves muscle contractile properties and endurance capacity in multiple sclerosis (MS). The impact of high intensity exercise remains unknown. Methods Thirty-four MS patients were randomized into a sedentary control group (SED, n = 11) and 2...

  6. 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

  7. Gait Recognition and Walking Exercise Intensity Estimation

    Directory of Open Access Journals (Sweden)

    Bor-Shing Lin

    2014-04-01

    Full Text Available Cardiovascular patients consult doctors for advice regarding regular exercise, whereas obese patients must self-manage their weight. Because a system for permanently monitoring and tracking patients’ exercise intensities and workouts is necessary, a system for recognizing gait and estimating walking exercise intensity was proposed. For gait recognition analysis, αβ filters were used to improve the recognition of athletic attitude. Furthermore, empirical mode decomposition (EMD was used to filter the noise of patients’ attitude to acquire the Fourier transform energy spectrum. Linear discriminant analysis was then applied to this energy spectrum for training and recognition. When the gait or motion was recognized, the walking exercise intensity was estimated. In addition, this study addressed the correlation between inertia and exercise intensity by using the residual function of the EMD and quadratic approximation to filter the effect of the baseline drift integral of the acceleration sensor. The increase in the determination coefficient of the regression equation from 0.55 to 0.81 proved that the accuracy of the method for estimating walking exercise intensity proposed by Kurihara was improved in this study.

  8. 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...

  9. Hydration during intense exercise training.

    Science.gov (United States)

    Maughan, R J; Meyer, N L

    2013-01-01

    Hydration status has profound effects on both physical and mental performance, and sports performance is thus critically affected. Both overhydration and underhydration - if sufficiently severe - will impair performance and pose a risk to health. Athletes may begin exercise in a hypohydrated state as a result of incomplete recovery from water loss induced in order to achieve a specific body mass target or due to incomplete recovery from a previous competition or training session. Dehydration will also develop in endurance exercise where fluid intake does not match water loss. The focus has generally been on training rather than on competition, but sweat loss and fluid replacement in training may have important implications. Hypohydration may impair training quality and may also increase stress levels. It is unclear whether this will have negative effects (reduced training quality, impaired immunity) or whether it will promote a greater adaptive response. Hypohydration and the consequent hyperthermia, however, can enhance the effectiveness of a heat acclimation program, resulting in improved endurance performance in warm and temperate environments. Drinking in training may be important in enhancing tolerance of the gut when athletes plan to drink in competition. The distribution of water between body water compartments may also be important in the initiation and promotion of cellular adaptations to the training stimulus. Copyright © 2013 Nestec Ltd., Vevey/S. Karger AG, Basel.

  10. Electromyographic, cerebral and muscle hemodynamic responses during intermittent, isometric contractions of the biceps brachii at three submaximal intensities

    Directory of Open Access Journals (Sweden)

    Yagesh eBhambhani

    2014-06-01

    Full Text Available This study examined the electromyographic, cerebral and muscle hemodynamic responses during intermittent isometric contractions of biceps brachii at 20%, 40% and 60% of maximal voluntary contraction (MVC. Eleven volunteers completed two minutes of intermittent isometric contractions (12/min at an elbow angle of 90° interspersed with three minutes rest between intensities in systematic order. Surface electromyography (EMG was recorded from the right biceps brachii and near infrared spectroscopy (NIRS was used to simultaneously measure left prefrontal and right biceps brachii oxyhemoglobin (HbO2, deoxyhemoglobin (HHb and total hemoglobin (Hbtot. Transcranial Doppler ultrasound was used to measure middle cerebral artery velocity (MCAv bilaterally. Finger photoplethysmography was used to record beat-to-beat blood pressure and heart rate. EMG increased with force output from 20% to 60% MVC (P0.05. MCAv increased from rest to exercise but was not different among intensities (P>0.05. Force output correlated with the root mean square EMG and changes in muscle HbO2 (P0.05 at all three intensities. Force output declined by 8% from the 1st to the 24th contraction only at 60% MVC and was accompanied by systematic increases in RMS, cerebral HbO2 and Hbtot with a levelling off in muscle HbO2 and Hbtot. These changes were independent of alterations in mean arterial pressure. Since cerebral blood flow and oxygenation were elevated at 60% MVC, we attribute the development of fatigue to reduced muscle oxygen availability rather than impaired central n

  11. Electromyographic, cerebral, and muscle hemodynamic responses during intermittent, isometric contractions of the biceps brachii at three submaximal intensities

    Science.gov (United States)

    Bhambhani, Yagesh; Fan, Jui-Lin; Place, Nicolas; Rodriguez-Falces, Javier; Kayser, Bengt

    2014-01-01

    This study examined the electromyographic, cerebral and muscle hemodynamic responses during intermittent isometric contractions of biceps brachii at 20, 40, and 60% of maximal voluntary contraction (MVC). Eleven volunteers completed 2 min of intermittent isometric contractions (12/min) at an elbow angle of 90° interspersed with 3 min rest between intensities in systematic order. Surface electromyography (EMG) was recorded from the right biceps brachii and near infrared spectroscopy (NIRS) was used to simultaneously measure left prefrontal and right biceps brachii oxyhemoglobin (HbO2), deoxyhemoglobin (HHb), and total hemoglobin (Hbtot). Transcranial Doppler ultrasound was used to measure middle cerebral artery velocity (MCAv) bilaterally. Finger photoplethysmography was used to record beat-to-beat blood pressure and heart rate. EMG increased with force output from 20 to 60% MVC (P MVC (P MVC (P MVC (P > 0.05). MCAv increased from rest to exercise but was not different among intensities (P > 0.05). Force output correlated with the root mean square EMG and changes in muscle HbO2 (P 0.05) at all three intensities. Force output declined by 8% from the 1st to the 24th contraction only at 60% MVC and was accompanied by systematic increases in RMS, cerebral HbO2 and Hbtot with a leveling off in muscle HbO2 and Hbtot. These changes were independent of alterations in mean arterial pressure. Since cerebral blood flow and oxygenation were elevated at 60% MVC, we attribute the development of fatigue to reduced muscle oxygen availability rather than impaired central neuronal activation. PMID:24966837

  12. 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.

  13. 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...

  14. 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.

  15. Speed and exercise intensity of recreational walkers.

    Science.gov (United States)

    Murtagh, Elaine M; Boreham, Colin A G; Murphy, Marie H

    2002-10-01

    Brisk walking has been identified as an activity suited to meet American College of Sport Medicine/Centers for Disease Control and Prevention recommendations for moderate intensity exercise (55-69% HR(max), 40-59% VO(2)R). However, little is known about whether recreational walkers self-select a pace which elicits this intensity and how they interpret the term "brisk walking." The walking speed of 82 adults was covertly observed in a public park. Fifty-nine of these participants demonstrated their interpretation of "brisk walking" and the speed was noted. Eleven of these subjects subsequently walked on a treadmill at their observed and "brisk walk" speeds. Heart rate (HR), respiratory gases, and ratings of perceived exertion (RPE) were measured. Mean observed and "brisk" walking speeds were 1.56 +/- 0.17 m. s(-1) and 1.79 +/- 0.19 m x s(-1) respectively (P exercise intensities during the treadmill test (n = 11) were 59.0 +/- 13.4% VO(2max) and 67.3 +/- 11.6% HR(max) for the observed speed (1.60 + 0.24 m x s(-1)). The brisk speed (1.86 +/- 0.12 m x s(-1)) equated to 68.6 +/- 14.9% VO(2max) and 78.5 +/- 15.5% HR(max). The speed and intensity selected by this group of walkers meets current recommendations for moderate intensity exercise. Instructing individuals to "walk briskly" prompts more vigorous activity. Copyright 2002 American Health Foundation and Elsevier Science (USA)

  16. Exercise intensity during official soccer matches

    Directory of Open Access Journals (Sweden)

    Daniel Barbosa Coelho

    2016-02-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n6p621   The aims of the study were: 1 to analyze the exercise intensity in several phases (six phases of 15 min of soccer matches; 2 to compare the match time spent above anaerobic threshold (AT between different age groups (U-17 and U-20; and 3 to compare the match time spent above AT between players’ positions (backs, midfielders, forwards and wingabcks. Forty-four male soccer players were analyzed. To express players’ effort, the heart rate (HR was continuously monitored in 29 official matches. Further, HR corresponding to the intensity at the onset of blood lactate accumulation (OBLA was obtained in a field test. The highest exercise intensity during match was observed in the 15-30 min period of the first half (p< 0.05. Match time spent above AT was not different between players from U-17 and U-20. In the comparison among players’ positions, wingbacks showed lower time above AT (p< 0.05 than players of other positions. The intensity of effort is higher in the 15 to 30 minutes of play (intermediate phase, probably because the players are more rested in the beginning and wearing out is progressive throughout the game. It is also noteworthy that the intensity of exercise (HR and time above AT of wingbacks was lower, probably because they usually are required to run a larger number of sprints and need more time below the AT to recover.

  17. Intense exercise training and immune function.

    Science.gov (United States)

    Gleeson, Michael; Williams, Clyde

    2013-01-01

    Regular moderate exercise reduces the risk of infection compared with a sedentary lifestyle, but very prolonged bouts of exercise and periods of intensified training are associated with increased infection risk. In athletes, a common observation is that symptoms of respiratory infection cluster around competitions, and even minor illnesses such as colds can impair exercise performance. There are several behavioral, nutritional and training strategies that can be adopted to limit exercise-induced immunodepression and minimize the risk of infection. Athletes and support staff can avoid transmitting infections by avoiding close contact with those showing symptoms of infection, by practicing good hand, oral and food hygiene and by avoiding sharing drinks bottles and cutlery. Medical staff should consider appropriate immunization for their athletes particularly when travelling to international competitions. The impact of intensive training stress on immune function can be minimized by getting adequate sleep, minimizing psychological stress, avoiding periods of dietary energy restriction, consuming a well-balanced diet that meets energy and protein needs, avoiding deficiencies of micronutrients (particularly iron, zinc, and vitamins A, D, E, B6 and B12), ingesting carbohydrate during prolonged training sessions, and consuming - on a daily basis - plant polyphenol containing supplements or foodstuffs and Lactobacillus probiotics. Copyright © 2013 Nestec Ltd., Vevey/S. Karger AG, Basel.

  18. 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.

  19. Exercise training in COPD: What is it about intensity?

    Science.gov (United States)

    Morris, Norman R; Walsh, James; Adams, Lewis; Alision, Jennifer

    2016-10-01

    Most of the current guidelines for pulmonary rehabilitation recommend higher, over lower, intensity exercise training for COPD. Typically, we consider intensity of exercise training to be a key component of any exercise training programme. Whilst studies of young individuals have demonstrated that higher exercise training intensity results in greater improvements in exercise capacity, the evidence for older patients is not so clear cut. In COPD, there is limited evidence regarding the optimal intensity of exercise training. Using both physiological (peak exercise capacity) and patient-centred (e.g. quality of life) outcomes, it remains inconclusive if higher intensity exercise training bestows any greater benefit than low-intensity exercise. If we examine the data from interval training studies, which used both high- and low-intensity interval and continuous exercise, we are able to generate more data for comparison. Unfortunately, these data are challenging to interpret due to heterogeneity in how interval training was prescribed. However, when we normalize the interval training data for training volume and examine the change in peak cycling power, there is a relationship between training intensity and increase in peak power (Wpeak , r = 0.68, P intensity continuous exercise, the additional data from interval training studies would suggest that higher intensity may be superior in terms of increases in Wpeak . Future studies should focus on establishing a threshold and an optimal training intensity for COPD. © 2016 Asian Pacific Society of Respirology.

  20. 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.

  1. 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...

  2. NEW EQUATIONS TO DETERMINE EXERCISE INTENSITY USING DIFFERENT EXERCISE MODES

    Directory of Open Access Journals (Sweden)

    Luís B Sardinha

    2012-04-01

    Full Text Available The purpose of this study was to determine new equations from the relationship of %·VO2max versus %HRmax, based on direct measures of oxygen uptake, in four exercise modes (leg cycling, rowing, stepping and running, in young adult females and males with low risk for cardiovascular disease. Ten adult males and ten females volunteered for the study. The participants performed an incremental test for each exercise mode until exhaustion. Regression analyses were carried out for each participant at a target % of VO2max and %HRmax was computed. At 40-90%·VO2max, the regression equations predicted similar values of %HRmax for males and females in the four exercise modes. In contrast, estimated %HRmax for cycling was higher at 40-70%·VO2max, when compared with stepping and running. The results support the notion that a single equation to predict target heart rate values for both males and females can be applied. Furthermore, at light and moderate intensities, leg cycling produces different %·VO2max-%HRmax regression equations than stepping and running.

  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. 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.

  5. 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.

  6. Immersible ergocycle prescription as a function of relative exercise intensity

    Directory of Open Access Journals (Sweden)

    Mauricio Garzon

    2017-06-01

    Conclusion: The %HRR–%VO2R relationship appears to be the most accurate for exercise training prescription on IE. This study offers new tools to better prescribe, control, and individualize exercise intensity on IE.

  7. 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.

  8. Evidence based exercise: Clinical benefits of high intensity interval training

    National Research Council Canada - National Science Library

    Shiraev, Tim; Barclay, Gabriella

    2012-01-01

    ...: This article describes the benefits of exercise for patients with cardiovascular and metabolic disease and details the numerous benefits of high intensity interval training (HIIT) in particular. Discussion...

  9. Effect of exercise modality and intensity on post-exercise interleukin-6 and hepcidin levels

    NARCIS (Netherlands)

    Sim, M.; Dawson, B.; Landers, G.; Swinkels, D.W.; Tjalsma, H.; Trinder, D.; Peeling, P.

    2013-01-01

    The effect of exercise modality and intensity on Interleukin-6 (IL-6), iron status, and hepcidin levels was investigated. Ten trained male triathletes performed 4 exercise trials including low-intensity continuous running (L-R), low-intensity continuous cycling (L-C), high-intensity interval running

  10. Physiological responses at the lactate-minimum-intensity with and without prior high-intensity exercise.

    Science.gov (United States)

    Zagatto, Alessandro Moura; Padulo, Johnny; Silva, Adelino Ramos Sanchez da; Müller, Paulo de Tarso Guerrero; Miyagi, Willian Eiji; Gobatto, Claudio Alexandre

    2016-11-01

    This study examined the physiological responses during exercise-to-exhaustion at the lactate-minimum-intensity with and without prior high-intensity exercise. Eleven recreationally trained males performed a graded exercise test, a lactate minimum test and two constant-load tests at lactate-minimum-intensity until exhaustion, which were applied with or without prior hyperlactatemia induction (i.e., 30-s Wingate test). The physiological responses were significantly different (P  0.05). In conclusion, the constant-load exercises performed at lactate-minimum-intensity with or without prior high-intensity exercise did not lead to the steady state of all analysed parameters; however, variables such as [La(-)], pH and [HCO3] - altered at the beginning of effort performed after high-intensity exercise - were reestablished after approximately 30 min of exercise.

  11. Thermal and Cardiovascular Strain from Hypohydration: Influence of Exercise Intensity

    National Research Council Canada - National Science Library

    Montain, S

    1996-01-01

    ...) strain induced from hypohydration during heat stress. We hypothesized that the added thermal and cardiovascular strain induced by hypohydration would be greater during high intensity than low intensity exercise...

  12. 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.

  13. High-intensity aerobic interval exercise in chronic heart failure.

    Science.gov (United States)

    Meyer, Philippe; Gayda, Mathieu; Juneau, Martin; Nigam, Anil

    2013-06-01

    Aerobic exercise training is strongly recommended in patients with heart failure (HF) and reduced left ventricular ejection fraction (LVEF) to improve symptoms and quality of life. Moderate-intensity aerobic continuous exercise (MICE) is the best established training modality in HF patients. For about a decade, however, another training modality, high-intensity aerobic interval exercise (HIIE), has aroused considerable interest in cardiac rehabilitation. Originally used by athletes, HIIE consists of repeated bouts of high-intensity exercise interspersed with recovery periods. The rationale for its use is to increase exercise time spent in high-intensity zones, thereby increasing the training stimulus. Several studies have demonstrated that HIIE is more effective than MICE, notably for improving exercise capacity in patients with HF. The aim of the present review is to describe the general principles of HIIE prescription, the acute physiological effects, the longer-term training effects, and finally the future perspectives of HIIE in patients with HF.

  14. Higher-intensity exercise helps cancer survivors remain motivated.

    Science.gov (United States)

    Martin, Eric; Battaglini, Claudio; Hands, Beth; Naumann, Fiona L

    2016-06-01

    The aim of the present study was to determine if exercise intensity impacts upon the psychosocial responses of breast and prostate cancer survivors to a rehabilitation program. Eighty-seven prostate and 72 breast cancer survivors participated in an 8-week exercise and supportive group psychotherapy intervention (n = 84) or control (n = 75) group. Intervention participants were randomized to low-to-moderate intensity exercise (LIG; n = 44; 60-65 % VO2peak, 50-65 % one repetition maximum (1RM)) or moderate-to-high intensity exercise (HIG; n = 40; 75-80 % VO2peak, 65-80 % 1RM) while controls continued usual care. Before and after the 8 weeks, all participants completed the Functional Assessment of Cancer Therapy-Breast or -Prostate to assess quality of life (QOL) and Behavioural Regulations of Exercise Version 2 for exercise motivation. Intervention participants also completed a follow-up assessment 4 months post-intervention. All three groups improved in QOL from baseline to post-intervention, with no significant differences. From post-intervention to follow-up, the LIG and HIG similarly maintained QOL scores. Between baseline and post-intervention, both intervention arms improved their motivation to exercise compared to the controls (p = 0.004). At the 4-month follow-up, the HIG had maintained their overall exercise motivation (p motivation (identified regulation, p = 0.047; intrinsic regulation, p = 0.007); however, the LIG had regressed. The structured intervention was successful at improving autonomous exercise motivation, regardless of exercise intensity. However, only those participants who had exercised at a higher intensity sustained their improvement. Intervention participation did not improve QOL more than controls. Higher-intensity exercise is more likely to result in more sustainable increases in motivation to exercise among cancer survivors.

  15. Walk or run? Is high-intensity exercise more effective than moderate-intensity exercise at reducing cardiovascular risk?

    Science.gov (United States)

    Rankin, A J; Rankin, A C; MacIntyre, P; Hillis, W S

    2012-05-01

    The benefits of exercise in the prevention of cardiovascular disease are irrefutable. However, the optimum 'dose' of exercise in order to derive the maximum cardiovascular benefit is not certain. Current national and international guidelines advocate the benefits of moderate-intensity exercise. The relative benefits of vigorous versus moderate-intensity exercise have been studied in large epidemiological studies, addressing coronary heart disease and mortality, as well as smaller randomized clinical trials which assessed effects on cardiovascular risk factors. There is evidence that exercise intensity, rather than duration or frequency, is the most important variable in determining cardioprotection. Applying this evidence into practice must take into account the impact of baseline fitness, compliance and the independent risk associated with a sedentary lifestyle. This review aims to evaluate the role of exercise intensity in the reduction of cardiovascular risk, and answer the question: should you be advising your patients to walk or run?

  16. Metformin improves performance in high-intensity exercise, but not anaerobic capacity in healthy male subjects.

    Science.gov (United States)

    Learsi, S K; Bastos-Silva, V J; Lima-Silva, A E; Bertuzzi, R; De Araujo, G G

    2015-10-01

    The aim of this study was to determine the ergogenic effects of metformin in high-intensity exercise, as well as its effects on anaerobic capacity, in healthy and physically active men. Ten subjects (mean (± standard deviation) maximal oxygen uptake (V˙O2max ) 38.6 ± 4.5 mL/kg per min) performed the following tests in a cycle ergometer: (i) an incremental test; (ii) six submaximal constant workload tests at 40%-90% (V˙O2max ); and (iii) two supramaximal tests (110% (V˙O2max ). Metformin (500 mg) or placebo was ingested 60 min before the supramaximal test. There were no significant differences between the placebo and metformin groups in terms of maximum accumulated oxygen deficit (2.8 ± 0.6 vs 3.0 ± 0.8 L, respectively; P = 0.08), lactate concentrations (7.8 ± 2.6 vs 7.5 ± 3.0 mmol/L, respectively; P = 0.75) or O2 consumed in either the last 30 s of exercise (40.4 ± 4.4 vs 39.9 ± 4.0 mL/kg per min, respectively; P = 0.35) or the first 110 s of exercise (29.0 ± 2.5 vs 29.5 ± 3.0 mL/kg per min, respectively; P = 0.42). Time to exhaustion was significantly higher after metformin than placebo ingestion (191 ± 33 vs 167 ± 32 s, respectively; P = 0.001). The fast component of V˙O2 recovery was higher in the metformin than placebo group (12.71 vs 12.18 mL/kg per min, respectively; P = 0.025). Metformin improved performance and anaerobic alactic contribution during high-intensity exercise, but had no effect on overall anaerobic capacity in healthy subjects. © 2015 Wiley Publishing Asia Pty Ltd.

  17. Exercise duration and intensity in a weight-loss program.

    Science.gov (United States)

    Chambliss, Heather O

    2005-03-01

    To examine the effect of duration and frequency of exercise on weight loss and cardiorespiratory fitness in previously sedentary, overweight, women. Randomized, controlled, 4-arm trial of 12-months duration. A university-based behavioral weight loss program during the years 2000 and 2001. Eligibility criteria were: women, 21 to 45 years of age, body mass index (BMI) 27 to 40, reporting exercise exercise or that would affect metabolism or weight loss, being treated for psychologic conditions, pregnant, recently pregnant, or planning pregnancy, having a medical condition that could affect metabolism or body weight (eg, diabetes) or that would limit exercise participation. All 201 participants were assigned to a standard behavioral weight loss program, which included regular group meetings and telephone calls, and caloric and dietary fat restrictions. Participants were given meal plans and kept weekly food diaries. The women were assigned to 1 of 4 exercise groups based on energy expenditure of 1000 kcal/wk or 2000 kcal/wk and exercise intensity (moderate versus vigorous). Exercise intensity was prescribed according to percentage of age-predicted maximal heart rate and rating of perceived exertion. Energy expenditure was converted to minutes of exercise per week. The groups were vigorous intensity/high duration, moderate intensity/high duration, moderate intensity/moderate duration, and vigorous intensity/moderate duration. All 4 groups started the program at moderate intensity and moderate duration (100 min/week of walking) and increased the vigor and duration of exercise to set targets of 200, 300, 200, and 150 min/week, for the groups respectively. Treadmills were provided to the participants, and feedback on their weekly exercise logs was given. At 6 and 12 months, changes in body weight and BMI were measured. Cardiorespiratory fitness was measured by a graded exercise treadmill test and expressed as percent change in oxygen consumption from baseline. Excluding 5

  18. Determining the anaerobic threshold in post-polio syndrome: comparison with current guidelines for training intensity prescription.

    NARCIS (Netherlands)

    Voorn, E.L.; Gerrits, K.H.L.; Koopman, F.S.; Nollet, F.; Beelen, A.

    2014-01-01

    Objectives To determine whether the anaerobic threshold (AT) can be identified in individuals with postpolio syndrome (PPS) using submaximal incremental exercise testing, and to compare current guidelines for intensity prescription in PPS with the AT. Design Cohort study. Setting Research

  19. Evidence based exercise - clinical benefits of high intensity interval training.

    Science.gov (United States)

    Shiraev, Tim; Barclay, Gabriella

    2012-12-01

    Aerobic exercise has a marked impact on cardiovascular disease risk. Benefits include improved serum lipid profiles, blood pressure and inflammatory markers as well as reduced risk of stroke, acute coronary syndrome and overall cardiovascular mortality. Most exercise programs prescribed for fat reduction involve continuous, moderate aerobic exercise, as per Australian Heart Foundation clinical guidelines. This article describes the benefits of exercise for patients with cardiovascular and metabolic disease and details the numerous benefits of high intensity interval training (HIIT) in particular. Aerobic exercise has numerous benefits for high-risk populations and such benefits, especially weight loss, are amplified with HIIT. High intensity interval training involves repeatedly exercising at a high intensity for 30 seconds to several minutes, separated by 1-5 minutes of recovery (either no or low intensity exercise). HIT is associated with increased patient compliance and improved cardiovascular and metabolic outcomes and is suitable for implementation in both healthy and 'at risk' populations. Importantly, as some types of exercise are contraindicated in certain patient populations and HIIT is a complex concept for those unfamiliar to exercise, some patients may require specific assessment or instruction before commencing a HIIT program.

  20. SALIVARY CORTISOL RESPONSES AND PERCEIVED EXERTION DURING HIGH INTENSITY AND LOW INTENSITY BOUTS OF RESISTANCE EXERCISE

    Directory of Open Access Journals (Sweden)

    Alison D. Egan

    2004-03-01

    Full Text Available The purpose of this study was to measure the salivary cortisol response to different intensities of resistance exercise. In addition, we wanted to determine the reliability of the session rating of perceived exertion (RPE scale to monitor resistance exercise intensity. Subjects (8 men, 9 women completed 2 trials of acute resistance training bouts in a counterbalanced design. The high intensity resistance exercise protocol consisted of six, ten-repetition sets using 75% of one repetition maximum (RM on a Smith machine squat and bench press exercise (12 sets total. The low intensity resistance exercise protocol consisted of three, ten-repetition sets at 30% of 1RM of the same exercises as the high intensity protocol. Both exercise bouts were performed with 2 minutes of rest between each exercise and sessions were repeated to test reliability of the measures. The order of the exercise bouts was randomized with least 72 hours between each session. Saliva samples were obtained immediately before, immediately after and 30 mins following each resistance exercise bout. RPE measures were obtained using Borg's CR-10 scale following each set. Also, the session RPE for the entire exercise session was obtained 30 minutes following completion of the session. There was a significant 97% increase in the level of salivary cortisol immediately following the high intensity exercise session (P<0.05. There was also a significant difference in salivary cortisol of 145% between the low intensity and high intensity exercise session immediately post-exercise (P<0.05. The low intensity exercise did not result in any significant changes in cortisol levels. There was also a significant difference between the session RPE values for the different intensity levels (high intensity 7.1 vs. low intensity 1.9 (P<0.05. The intraclass correlation coefficient for the session RPE measure was 0.95. It was concluded that the session RPE method is a valid and reliable method of

  1. Comparison of aerobic exercise intensity prescription methods in breast cancer.

    Science.gov (United States)

    Kirkham, Amy A; Campbell, Kristin L; McKenzie, Donald C

    2013-08-01

    Exercise plays an important role in cancer rehabilitation, but a precise prescription of exercise intensity is required to maximize the benefits of this intervention. It is unknown whether different methods of prescribing aerobic exercise intensity achieve the same intensity. Breast cancer treatments may alter exercise response and thereby may affect the accuracy of these methods. The purpose of this study was to compare the accuracy and achieved intensity of four common methods of prescribing exercise intensity within and between breast cancer patients recently finished chemotherapy (n = 10), survivors finished treatment (n = 10), and healthy controls (n = 10). The methods compared were as follows: the American College of Sports Medicine's metabolic equation for treadmill walking (METW), heart rate reserve (HRR), direct heart rate (DIRECT HR), and RPE. The methods were used to prescribe 60% oxygen consumption reserve (VO2R) in four randomly assigned 10-min periods of treadmill walking with expired gas collection to evaluate 1) achieved intensity (measured % VO2R) and 2) accuracy (defined as: [60% VO2R-achieved intensity]). The accuracy of the methods was not equivalent across groups (P = 0.04). HRR and METW did not differ across groups and were most accurate in patients. HRR, METW, and DIRECT HR were all more accurate than RPE in survivors (P ≤ 0.01). RPE was the least accurate in all groups. The accuracy of DIRECT HR was much lower in patients than that in survivors and controls (P ≤ 0.01). The four methods of exercise intensity prescription varied in accuracy in prescribing 60% VO2R and did not achieve equivalent exercise intensities within breast cancer patients, survivors, and healthy controls. HRR and METW were the most accurate methods for exercise intensity prescription in breast cancer patients and survivors.

  2. NEW EQUATIONS TO DETERMINE EXERCISE INTENSITY USING DIFFERENT EXERCISE MODES

    OpenAIRE

    Luís B Sardinha; Manuel João Coelho e Silva; Raul A Martins

    2012-01-01

    The purpose of this study was to determine new equations from the relationship of %·VO2max versus %HRmax, based on direct measures of oxygen uptake, in four exercise modes (leg cycling, rowing, stepping and running), in young adult females and males with low risk for cardiovascular disease. Ten adult males and ten females volunteered for the study. The participants performed an incremental test for each exercise mode until exhaustion. Regression analyses were carried out for each participant ...

  3. Effect of exercise intensity, duration and mode on post-exercise oxygen consumption.

    Science.gov (United States)

    Børsheim, Elisabet; Bahr, Roald

    2003-01-01

    In the recovery period after exercise there is an increase in oxygen uptake termed the 'excess post-exercise oxygen consumption' (EPOC), consisting of a rapid and a prolonged component. While some studies have shown that EPOC may last for several hours after exercise, others have concluded that EPOC is transient and minimal. The conflicting results may be resolved if differences in exercise intensity and duration are considered, since this may affect the metabolic processes underlying EPOC. Accordingly, the absence of a sustained EPOC after exercise seems to be a consistent finding in studies with low exercise intensity and/or duration. The magnitude of EPOC after aerobic exercise clearly depends on both the duration and intensity of exercise. A curvilinear relationship between the magnitude of EPOC and the intensity of the exercise bout has been found, whereas the relationship between exercise duration and EPOC magnitude appears to be more linear, especially at higher intensities. Differences in exercise mode may potentially contribute to the discrepant findings of EPOC magnitude and duration. Studies with sufficient exercise challenges are needed to determine whether various aerobic exercise modes affect EPOC differently. The relationships between the intensity and duration of resistance exercise and the magnitude and duration of EPOC have not been determined, but a more prolonged and substantial EPOC has been found after hard- versus moderate-resistance exercise. Thus, the intensity of resistance exercise seems to be of importance for EPOC. Lastly, training status and sex may also potentially influence EPOC magnitude, but this may be problematic to determine. Still, it appears that trained individuals have a more rapid return of post-exercise metabolism to resting levels after exercising at either the same relative or absolute work rate; however, studies after more strenuous exercise bouts are needed. It is not determined if there is a sex effect on EPOC

  4. Psychophysiological Responses to Group Exercise Training Sessions: Does Exercise Intensity Matter?

    Directory of Open Access Journals (Sweden)

    Matteo Vandoni

    Full Text Available Group exercise training programs were introduced as a strategy for improving health and fitness and potentially reducing dropout rates. This study examined the psychophysiological responses to group exercise training sessions. Twenty-seven adults completed two group exercise training sessions of moderate and vigorous exercise intensities in a random and counterbalanced order. The %HRR and the exertional and arousal responses to vigorous session were higher than those during the moderate session (p<0.05. Consequently, the affective responses to vigorous session were less pleasant than those during moderate session (p<0.05. These results suggest that the psychophysiological responses to group exercise training sessions are intensity-dependent. From an adherence perspective, interventionists are encouraged to emphasize group exercise training sessions at a moderate intensity to maximize affective responses and to minimize exertional responses, which in turn may positively affect future exercise behavior.

  5. Exercise intensity classification in cancer patients undergoing allogeneic HCT.

    Science.gov (United States)

    Kuehl, Rea; Scharhag-Rosenberger, Friederike; Schommer, Kai; Schmidt, Martina E; Dreger, Peter; Huber, Gerhard; Bohus, Martin; Ulrich, Cornelia M; Wiskemann, Joachim

    2015-05-01

    Exercise intervention studies during and after cancer treatment show beneficial effects for various physical and psychosocial outcomes. Current exercise intensity guidelines for cancer patients are rather general and have been adapted from American College of Sports Medicine (ACSM) recommendations for healthy individuals. Intensive cancer treatment regimens such as allogeneic hematopoietic stem cell transplantation (allo-HCT) may change the cardiovascular response to acute exercise. Therefore, we evaluated the relationships between %V˙O2 reserve (%V˙O2R, reference) and %HRR, %HRmax, and %V˙O2max and compared calculated intensities with given intensities by ACSM. Measurements before and 180 d after allo-HCT from a randomized controlled trial were used. Only patients who reached maximal effort and at least two exercise stages in our maximal incremental cycling test were included. Before allo-HCT, 106 patients were included, and 180 d after treatment, 49 patients met our inclusion criteria. Individual regression lines were calculated with V˙O2R as the reference. Calculated exercise intensities for endurance training prescription were compared with ACSM values. Before allo-HCT, %HRR values of patients were significantly lower than ACSM values, and %HRmax and %V˙O2max values were significantly higher (except 90% HRmax, which was significantly lower, all P exercise intensity recommendations for endurance training may not be applicable for cancer patients during and 180 d after allo-HCT because they may not meet the targeted intensity class, with the exception of %HRR 180 d after allo-HCT.

  6. How to Regulate the Acute Physiological Response to “Aerobic” High-Intensity Interval Exercise

    Science.gov (United States)

    Tschakert, Gerhard; Kroepfl, Julia; Mueller, Alexander; Moser, Othmar; Groeschl, Werner; Hofmann, Peter

    2015-01-01

    The acute physiological processes during “aerobic” high-intensity interval exercise (HIIE) and their regulation are inadequately studied. The main goal of this study was to investigate the acute metabolic and cardiorespiratory response to long and short HIIE compared to continuous exercise (CE) as well as its regulation and predictability. Six healthy well-trained sport students (5 males, 1 female; age: 25.7 ± 3.1 years; height: 1.80 ± 0.04 m; weight: 76.7 ± 6.4 kg; VO2max: 4.33 ± 0.7 l·min-1) performed a maximal incremental exercise test (IET) and subsequently three different exercise sessions matched for mean load (Pmean) and exercise duration (28 min): 1) long HIIE with submaximal peak workloads (Ppeak = power output at 95 % of maximum heart rate), peak workload durations (tpeak) of 4 min, and recovery durations (trec) of 3 min, 2) short HIIE with Ppeak according to the maximum power output (Pmax) from IET, tpeak of 20 s, and individually calculated trec (26.7 ± 13.4 s), and 3) CE with a target workload (Ptarget) equating to Pmean of HIIE. In short HIIE, mean lactate (Lamean) (5.22 ± 1.41 mmol·l-1), peak La (7.14 ± 2.48 mmol·l-1), and peak heart rate (HRpeak) (181.00 ± 6.66 b·min-1) were significantly lower compared to long HIIE (Lamean: 9.83 ± 2.78 mmol·l-1; Lapeak: 12.37 ± 4.17 mmol·l-1, HRpeak: 187.67 ± 5.72 b·min-1). No significant differences in any parameters were found between short HIIE and CE despite considerably higher peak workloads in short HIIE. The acute metabolic and peak cardiorespiratory demand during “aerobic” short HIIE was significantly lower compared to long HIIE and regulable via Pmean. Consequently, short HIIE allows a consciously aimed triggering of specific and desired or required acute physiological responses. Key points High-intensity interval exercise (HIIE) with short peak workload durations (tpeak) induce a lower acute metabolic and peak cardiorespiratory response compared to intervals with long tpeak

  7. The beneficial role of intensive exercise on Parkinson disease progression.

    Science.gov (United States)

    Frazzitta, Giuseppe; Balbi, Pietro; Maestri, Roberto; Bertotti, Gabriella; Boveri, Natalia; Pezzoli, Gianni

    2013-06-01

    In the last decade, a considerable number of articles has shown that exercise is effective in improving motor performance in Parkinson disease. In particular, recent studies have focused on the efficacy of intensive exercise in achieving optimal results in the rehabilitation of patients with Parkinson disease. The effects of intensive exercise in promoting cell proliferation and neuronal differentiation in animal models are reported in a large cohort of studies, and these neuroplastic effects are probably related to increased expression of a variety of neurotrophic factors. The authors outline the relation between intensive exercises and neuroplastic activity on animal models of Parkinson disease and discuss the clinical results of different intensive strategies on motor performance and disease progression in patients with Parkinson disease.

  8. Heart Rate Variability: Effect of Exercise Intensity on Postexercise Response

    Science.gov (United States)

    James, David V. B.; Munson, Steven C.; Maldonado-Martin, Sara; De Ste Croix, Mark B. A.

    2012-01-01

    The purpose of the present study was to investigate the influence of two exercise intensities (moderate and severe) on heart rate variability (HRV) response in 16 runners 1 hr prior to (-1 hr) and at +1 hr, +24 hr, +48 hr, and +72 hr following each exercise session. Time domain indexes and a high frequency component showed a significant decrease…

  9. High-intensity interval training evokes larger serum BDNF levels compared with intense continuous exercise.

    Science.gov (United States)

    Saucedo Marquez, Cinthia Maria; Vanaudenaerde, Bart; Troosters, Thierry; Wenderoth, Nicole

    2015-12-15

    Exercise can have a positive effect on the brain by activating brain-derived neurotrophic factor (BDNF)-related processes. In healthy humans there appears to be a linear relationship between exercise intensity and the positive short-term effect of acute exercise on BDNF levels (i.e., the highest BDNF levels are reported after high-intensity exercise protocols). Here we performed two experiments to test the effectiveness of two high-intensity exercise protocols, both known to improve cardiovascular health, to determine whether they have a similar efficacy in affecting BDNF levels. Participants performed a continuous exercise (CON) protocol at 70% of maximal work rate and a high-intensity interval-training (HIT) protocol at 90% of maximal work rate for periods of 1 min alternating with 1 min of rest (both protocols lasted 20 min). We observed similar BDNF kinetics in both protocols, with maximal BDNF concentrations being reached toward the end of training (experiment 1). We then showed that both exercise protocols significantly increase BDNF levels compared with a rest condition (CON P = 0.04; HIT P high intensity exercise are slightly more effective than continuous high-intensity exercise for elevating serum BDNF. Additionally, 73% of the participants preferred the HIT protocol (P = 0.02). Therefore, we suggest that the HIT protocol might represent an effective and preferred intervention for elevating BDNF levels and potentially promoting brain health. Copyright © 2015 the American Physiological Society.

  10. Endothelin-1 and Exercise Intensity in Sedentary Adolescents with Obesity

    Directory of Open Access Journals (Sweden)

    Brooke E. Starkoff

    2015-01-01

    Full Text Available Inactivity combined with obesity during adolescence increases the risk of future cardiovascular disease. The study purpose was to compare the influence of differing intensities of exercise on endothelial function in sedentary adolescents with obesity. Participants were randomized to one of two groups in a 6-week exercise intervention: moderate intensity (MOD or high intensity interval exercise (HIIE. Endothelial function was assessed pre- and post-intervention via fasted serum levels of endothelin-1 (ET-1. Pre-measures of ET-1 concentrations were elevated at baseline. No significant differences in ET-1 were found between or within exercise groups. However, in the HIIE group, ET-1 was inversely associated with percentages of age predicted maximal heart rate achieved during the intervention (p=0.035, r=-0.567. The exercise interventions did not positively change ET-1 levels, yet participants who exercised at higher intensities in the HIIE group experienced greater decreases in ET-1. Keywords: childhood obesity, endothelial function, high intensity interval exercise

  11. Immersible ergocycle prescription as a function of relative exercise intensity

    OpenAIRE

    Mauricio Garzon; Mathieu Gayda; Anil Nigam; Alain-Steve Comtois; Martin Juneau

    2017-01-01

    Purpose: The purpose of this study was to establish the relationship between various expressions of relative exercise intensity percentage of maximal oxygen uptake (%VO2max), percentage of maximal heart rate (%HRmax), %VO2 reserve (%VO2R), and %HR reserve (%HRR)) in order to obtain the more appropriate method for exercise intensity prescription when using an immersible ergocycle (IE) and to propose a prediction equation to estimate oxygen consumption (VO2) based on IE pedaling rate (rpm) for ...

  12. Exercise intensity prescription during heat stress: A brief review.

    Science.gov (United States)

    Wingo, J E

    2015-06-01

    Exercise intensity can be prescribed using a variety of indices, such as rating of perceived exertion, heart rate, levels of absolute intensity (e.g., metabolic equivalents), and levels of relative intensity [e.g., percentage of maximal aerobic capacity (% V ˙ O 2 m a x ) or percentage of oxygen uptake reserve (% V ˙ O 2 R )]. Heart rate has a linear relationship with oxygen uptake, is easy to measure, and requires relatively inexpensive monitoring equipment, so it is commonly used to monitor exercise intensity. During heat stress, however, cardiovascular adjustments - including a rise in heart rate that is disproportionate to absolute intensity - result in diminished aerobic capacity and performance. These adjustments include cardiovascular drift, the progressive rise in heart rate and fall in stroke volume over time during prolonged, constant-rate exercise. A variety of factors have been shown to modulate the magnitude of cardiovascular drift, e.g., hyperthermia, dehydration, exercise intensity, and ambient temperature. Regardless of the mode of manipulation, decreases in stroke volume with cardiovascular drift are associated with proportionally similar decreases in V ˙ O 2 m a x , which affects the relationship between heart rate and relative metabolic intensity (% V ˙ O 2 m a x or % V ˙ O 2 R ). This review summarizes the current state of knowledge regarding the influence of cardiovascular drift and reduced V ˙ O 2 m a x on exercise intensity prescription in hot conditions. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Methods of prescribing relative exercise intensity: physiological and practical considerations.

    Science.gov (United States)

    Mann, Theresa; Lamberts, Robert Patrick; Lambert, Michael Ian

    2013-07-01

    Exercise prescribed according to relative intensity is a routine feature in the exercise science literature and is intended to produce an approximately equivalent exercise stress in individuals with different absolute exercise capacities. The traditional approach has been to prescribe exercise intensity as a percentage of maximal oxygen uptake (VO2max) or maximum heart rate (HRmax) and these methods remain common in the literature. However, exercise intensity prescribed at a %VO2max or %HRmax does not necessarily place individuals at an equivalent intensity above resting levels. Furthermore, some individuals may be above and others below metabolic thresholds such as the aerobic threshold (AerT) or anaerobic threshold (AnT) at the same %VO2max or %HRmax. For these reasons, some authors have recommended that exercise intensity be prescribed relative to oxygen consumption reserve (VO2R), heart rate reserve (HRR), the AerT, or the AnT rather than relative to VO2max or HRmax. The aim of this review was to compare the physiological and practical implications of using each of these methods of relative exercise intensity prescription for research trials or training sessions. It is well established that an exercise bout at a fixed %VO2max or %HRmax may produce interindividual variation in blood lactate accumulation and a similar effect has been shown when relating exercise intensity to VO2R or HRR. Although individual variation in other markers of metabolic stress have seldom been reported, it is assumed that these responses would be similarly heterogeneous at a %VO2max, %HRmax, %VO2R, or %HRR of moderate-to-high intensity. In contrast, exercise prescribed relative to the AerT or AnT would be expected to produce less individual variation in metabolic responses and less individual variation in time to exhaustion at a constant exercise intensity. Furthermore, it would be expected that training prescribed relative to the AerT or AnT would provide a more homogenous training

  14. Repeated high-intensity exercise in professional rugby union.

    Science.gov (United States)

    Austin, Damien; Gabbett, Tim; Jenkins, David

    2011-07-01

    The aim of the present study was to describe the frequency, duration, and nature of repeated high-intensity exercise in Super 14 rugby union. Time-motion analysis was used during seven competition matches over the 2008 and 2009 Super 14 seasons; five players from each of four positional groups (front row forwards, back row forwards, inside backs, and outside backs) were assessed (20 players in total). A repeated high-intensity exercise bout was considered to involve three or more sprints, and/or tackles and/or scrum/ruck/maul activities within 21 s during the same passage of play. The range of repeated high-intensity exercise bouts for each group in a match was as follows: 11-18 for front row forwards, 11-21 for back row forwards, 13-18 for inside backs, and 2-11 for outside backs. The durations of the most intense repeated high-intensity exercise bouts for each position ranged from 53 s to 165 s and the minimum recovery periods between repeated high-intensity exercise bouts ranged from 25 s for the back row forwards to 64 s for the front row forwards. The present results show that repeated high-intensity exercise bouts vary in duration and activities relative to position but all players in a game will average at least 10 changes in activity in the most demanding bouts and complete at least one tackle and two sprints. The most intense periods of activity are likely to last as long as 120 s and as little as 25 s recovery may separate consecutive repeated high-intensity exercise bouts. The present findings can be used by coaches to prepare their players for the most demanding passages of play likely to be experienced in elite rugby union.

  15. Exercise intensity and cardiovascular responses during and after exercise on pilates basic exercise program in comparison with those brisk walking

    OpenAIRE

    丹後, 亮子; 向本, 敬洋; 植田, 央; 韓, 一栄; 山口, 実由紀; 大野, 誠

    2012-01-01

    The purpose of this study was to investigate exercise intensity and cardiovascular responses during and after exercise on Pilates basic exercise program. Subjects were eleven women (age 38.3±6.3 years, height 160.1±5.4 cm, body weight 51.6±5.4 kg). They performed the following two exercises for 30 minutes on separate days; 1) Pilates basic exercise, 2) brisk walking (95 m/min). Oxygen uptake (VO2) was measured by breath-by-breath with monitoring of the heart rate (HR) during the exercise sess...

  16. Age does not affect exercise intensity progression among women.

    Science.gov (United States)

    Ciolac, Emmanuel G; Brech, Guilherme C; Greve, Júlia M D

    2010-11-01

    It has been recommended that the intensity of exercise training (ET) should progress slowly with lower increments in older than in young people. However, scientific evidence supporting this recommendation is lacking. Our aim was to examine possible influences of age on exercise intensity progression in healthy women. Seventeen young (29.1 ± 5.7 years) and 16 older women (64.5 ± 4.5 years) underwent 13 weeks of ET consisting of cycle ergometry (CE, 65-75% of reserve heart rate), whole-body resistance exercise (RE, 60% of 1 repetition maximum [1RM]), and stretching. Muscle strength was assessed before and after ET by the 1RM. Cycle ergometry and RE workloads were recorded for each exercise session, and increases of 5-10% were made whenever adaptation occurred. Absolute muscle strength after ET improved (p groups, and there were no significant differences between groups. Relative exercise intensity progression was not significantly different between groups for RE (Pearson's correlation = 0.98 ± 0.01), but it was greater in older women for CE (p = 0.047). The ET was safe because no injuries or major muscle pain was observed in either group. These results suggest that healthy older women are capable of exercising and increasing exercise intensity in the same way as young women.

  17. Muscle lactate metabolism in recovery from intense exhaustive exercise: impact of light exercise.

    Science.gov (United States)

    Bangsbo, J; Graham, T; Johansen, L; Saltin, B

    1994-10-01

    This study examined the effect of low-intensity exercise on lactate metabolism during the first 10 min of recovery from high-intensity exercise. Subjects exercised (61.0 +/- 5.4 W) one leg to exhaustion (approximately 3.5 min), and after 1 h of rest they performed the same exhaustive exercise with the other leg. For one leg the intense exercise was followed by rest [passive (P) leg], and for the other leg the exercise was followed by a 10-min period with low-intensity exercise at a work rate of 10 W [active (A) leg]. The muscle lactate concentration after the intense exercise was the same in the P and A legs, but after 10 min of recovery, the lactate concentration and the arterial blood lactate level were higher for the P leg than for the A leg (both P O2 consumption during 10 min of recovery was 440 and 750 ml for the P and A legs, respectively. The present data suggest that a lowered blood lactate level during active recovery is due to an elevated muscle lactate metabolism and is not caused by a transient higher release of lactate from the exercising muscles coupled with greater uptake in other tissues.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Exercise-induced hypoalgesia: Pain tolerance, preference and tolerance for exercise intensity, and physiological correlates following dynamic circuit resistance exercise.

    Science.gov (United States)

    Baiamonte, Brandon A; Kraemer, Robert R; Chabreck, Chelsea N; Reynolds, Matthew L; McCaleb, Kayla M; Shaheen, Georgia L; Hollander, Daniel B

    2017-09-01

    Previous research has demonstrated significant decreases in pain perception in healthy individuals following both aerobic and upper body resistance exercise, but research on circuit training has been limited. The purpose of the study was to determine the effects of a strenuous bout of dynamic circuit resistance exercise on pain threshold and pain tolerance in conjunction with changes in blood lactate levels, heart rate (HR), and perceived exertion. A sample of 24 college-age students participated in 2 sessions: (1) a maximal strength testing session and (2) a circuit training bout of exercise that consisted of 3 sets of 12 repetitions with a 1:1 work to rest ratio at 60% one-repetition maximum (1-RM) predicted from a three-repetition maximum (3-RM) for 9 exercises. Participants exhibited increases in pain tolerance, blood lactate levels, HR and perceived exertion following resistance exercise. Preference for exercise intensity was positively correlated with lactate post exercise and tolerance for exercise intensity was positively correlated with pain tolerance and lactate post exercise. In conclusion, this is the first study to demonstrate increases in pain tolerance following a dynamic circuit resistance exercise protocol and disposition for exercise intensity may influence lactate and pain responses to circuit resistance exercise.

  19. Study in Parkinson disease of exercise (SPARX): translating high-intensity exercise from animals to humans.

    Science.gov (United States)

    Moore, Charity G; Schenkman, Margaret; Kohrt, Wendy M; Delitto, Anthony; Hall, Deborah A; Corcos, Daniel

    2013-09-01

    A burgeoning literature suggests that exercise has a therapeutic benefit in persons with Parkinson disease (PD) and in animal models of PD, especially when animals exercise at high intensity. If exercise is to be prescribed as "first-line" or "add-on" therapy in patients with PD, we must demonstrate its efficacy and dose-response effects through testing phases similar to those used in the testing of pharmacologic agents. The SPARX Trial is a multicenter, randomized, controlled, single-blinded, Phase II study that we designed to test the feasibility of using high-intensity exercise to modify symptoms of PD and to simultaneously test the nonfutility of achieving a prespecified change in patients' motor scores on the Unified Parkinson Disease Rating Scale (UPDRS). The trial began in May 2102 and is in the process of screening, enrolling, and randomly assigning 126 patients with early-stage PD to 1 of 3 groups: usual care (wait-listed controls), moderate-intensity exercise (4 days/week at 60%-65% maximal heart rate [HRmax]), or high-intensity exercise (4 days/week at 80%-85% HRmax). At 6-month follow-up, the trial is randomly reassigning usual care participants to a moderate-intensity or high-intensity exercise group for the remaining 6 months. The goals of the Phase II trial are to determine if participants can exercise at moderate and high intensities; to determine if either exercise yields benefits consistent with meaningful clinical change (nonfutility); and to document safety and attrition. The advantage of using a non-futility approach allows us to efficiently determine if moderate- or high-intensity exercise warrants further large-scale investigation in PD. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Training for intense exercise performance: high-intensity or high-volume training?

    Science.gov (United States)

    Laursen, P B

    2010-10-01

    Performance in intense exercise events, such as Olympic rowing, swimming, kayak, track running and track cycling events, involves energy contribution from aerobic and anaerobic sources. As aerobic energy supply dominates the total energy requirements after ∼75s of near maximal effort, and has the greatest potential for improvement with training, the majority of training for these events is generally aimed at increasing aerobic metabolic capacity. A short-term period (six to eight sessions over 2-4 weeks) of high-intensity interval training (consisting of repeated exercise bouts performed close to or well above the maximal oxygen uptake intensity, interspersed with low-intensity exercise or complete rest) can elicit increases in intense exercise performance of 2-4% in well-trained athletes. The influence of high-volume training is less discussed, but its importance should not be downplayed, as high-volume training also induces important metabolic adaptations. While the metabolic adaptations that occur with high-volume training and high-intensity training show considerable overlap, the molecular events that signal for these adaptations may be different. A polarized approach to training, whereby ∼75% of total training volume is performed at low intensities, and 10-15% is performed at very high intensities, has been suggested as an optimal training intensity distribution for elite athletes who perform intense exercise events. © 2010 John Wiley & Sons A/S.

  1. 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.

  2. 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.

  3. High intensity exercise or conventional exercise for patients with rheumatoid arthritis?: outcome expectations of patients, rheumatologists, and physiotherapists.

    NARCIS (Netherlands)

    Munneke, M.; Jong, Z. de; Zwinderman, A.H.; Ronday, H.K.; Ende, C.H.M. van den; Vliet Vlieland, T.P.M.; Hazes, J.M.W.

    2004-01-01

    OBJECTIVE: To examine the outcome expectations of RA patients, rheumatologists, and physiotherapists regarding high intensity exercise programmes compared with conventional exercise programmes. METHODS: An exercise outcome expectations questionnaire was administered to 807 RA patients, 153

  4. High intensity exercise or conventional exercise for patients with rheumatoid arthritis? Outcome expectations of patients, rheumatologists, and physiotherapists

    NARCIS (Netherlands)

    Munneke, M.; de Jong, Z.; Zwinderman, A. H.; Ronday, H. K.; van den Ende, C. H. M.; Vliet Vlieland, T. P. M.; Hazes, J. M. W.

    2004-01-01

    OBJECTIVE: To examine the outcome expectations of RA patients, rheumatologists, and physiotherapists regarding high intensity exercise programmes compared with conventional exercise programmes. METHODS: An exercise outcome expectations questionnaire was administered to 807 RA patients, 153

  5. The effect of exercise intensity on calf volume and thermoregulatory responses during upper body exercise

    Directory of Open Access Journals (Sweden)

    Botoms Lindzi M.

    2011-01-01

    Full Text Available During upper body exercise the vascular adaptations of the leg have been reported to play an important thermoregulatory role. This study examined the effect of exercise intensity on thermoregulation during upper body exercise. Nine healthy male participants undertook an incremental exercise test on an arm crank ergo meter to determine peak power (Wpeak. The participants performed four experimental trials involving 5 minutes of arm exercise at either 45, 60, 75, or 90% Wpeak (70 rev.min-1 followed by 30 minutes of passive recovery. Aural and skin temperatures, upper arm and calf heat flow were recorded. Calf volume was measured during exercise using plethysmography. During exercise at 45, 60, 75 and 90% Wpeak calf volume decreased (P<0.05 by -0.7±0.8, -1.4±0.9, -1.2±0.6 and -1.6±0.7% respectively. Differences were observed between 45 and 60% Wpeak, and 45 and 90% Wpeak (P<0.05. The results of this study suggest a redistribution of blood from the relatively inactive lower body during arm exercise of intensities up to 60%Wpeak after which point calf volume does not significantly decrease further. Therefore, the redistribution of blood from the inactive lower body does not produce a similar intensity dependent response to visceral blood flow during lower body exercise.

  6. Adherence to moderate-intensity exercise during breast cancer therapy.

    Science.gov (United States)

    Pickett, Mary; Mock, Victoria; Ropka, Mary E; Cameron, Lane; Coleman, Meghan; Podewils, Laura

    2002-01-01

    The aims of this pilot study were the following: 1) to examine patterns of adherence to a brisk walking program in women receiving adjuvant chemotherapy or radiation therapy for newly diagnosed breast cancer using a prospective, randomized, controlled experimental design; 2) to examine the influence of disease symptoms and treatment side effects on exercise levels; and 3) to suggest methods that may improve future clinical trials of moderate-intensity exercise in similar populations. Fifty-two patients with newly diagnosed breast cancer were randomly assigned to one of two treatment arms: usual care or usual care plus exercise. Those assigned to the exercise group received a standardized, self-administered, home-based brisk walking intervention in addition to usual care. Each day subjects completed self-report diary forms that elicited information about activity levels, and the occurrence of symptoms and side effects during cancer treatment. Analyses of self-reported daily activity levels revealed a diffusion of treatment effect. Fifty percent of the usual-care group reported maintaining or increasing their physical activity to a moderate-intensity level, while 33% of the exercise group did not exercise at the prescribed levels. Analyses of self-reported disease symptoms and treatment side effects did not reveal clinically meaningful differences between the two groups. The results of this study suggest that women who exercised regularly before receiving a breast cancer diagnosis attempted to maintain their exercise programs. Women who lead sedentary lifestyles may benefit from a structured exercise program that includes information and support related to exercise adherence strategies.

  7. High intensity exercise enhances platelet reactivity to shear stress and coagulation during and after exercise.

    Science.gov (United States)

    Ikarugi, Hideo; Shibata, Masashi; Shibata, Shiori; Ishii, Hiromitsu; Taka, Tomomi; Yamamoto, Junichiro

    2003-01-01

    Platelets play a crucial role in the pathogenesis of acute cardiac events, such as angina, myocardial infarction and sudden death. It is believed that regular low-intensity exercise can reduce, while high-intensity exercise may provoke acute cardiac events. The aim of the present study was to investigate the effect of acute exercise both at low and high intensities on the ventilatory threshold (VT), platelet reactivity and coagulation before and after exercise. Platelet reactivity and coagulation were measured under flow condition, using native blood, by hemostatometry. Seven healthy young men (age: 20-29 years) performed bicycle ergometer exercise for 30 min at intensities of 90% (Ex-VT90% or approximately 55% VO(2max)) and 130% (Ex-VT130% or 80% VO(2max)) of individual VT. Blood cell counts, hematocrit, blood lactic acid and plasma catecholamine levels were slightly but significantly increased after Ex-VT90% and markedly after Ex-VT130% after 30 min exercise. Subsequent to the exercise, the elevated blood cell counts decreased to the resting levels both at Ex-VT90% and at Ex-VT130%. Platelet reactivity to shear stress and dynamic coagulation were significantly enhanced immediately and 30 min after Ex-130%VT. In contrast, no significant changes occurred in those of Ex-90%VT. The present study suggests that high-intensity exercise-induced platelet hyperreactivity and hypercoagulable state may pose an increased risk for acute, sometimes fatal cardiac event. On the other hand, our findings support the view that low-intensity exercise does not present a risk of thrombosis. Copyright 2003 S. Karger AG, Basel

  8. 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.

  9. Acute Exercise and Motor Memory Consolidation: The Role of Exercise Intensity.

    Directory of Open Access Journals (Sweden)

    Richard Thomas

    Full Text Available A single bout of high intensity aerobic exercise (~90% VO2peak was previously demonstrated to amplify off-line gains in skill level during the consolidation phase of procedural memory. High intensity exercise is not always a viable option for many patient groups or in a rehabilitation setting where low to moderate intensities may be more suitable. The aim of this study was to investigate the role of intensity in mediating the effects of acute cardiovascular exercise on motor skill learning. We investigated the effects of different exercise intensities on the retention (performance score of a visuomotor accuracy tracking task. Thirty six healthy male subjects were randomly assigned to one of three groups that performed either a single bout of aerobic exercise at 20 min post motor skill learning at 45% (EX45, 90% (EX90 maximal power output (Wmax or rested (CON. Randomization was stratified to ensure that the groups were matched for relative peak oxygen consumption (ml O2/min/kg and baseline score in the tracking task. Retention tests were carried out at 1 (R1 and 7 days (R7 post motor skill learning. At R1, changes in performance scores were greater for EX90 compared to CON (p<0.001 and EX45 (p = 0.011. The EX45 and EX90 groups demonstrated a greater change in performance score at R7 compared to the CON group (p = 0.003 and p<0.001, respectively. The change in performance score for EX90 at R7 was also greater than EX45 (p = 0.049. We suggest that exercise intensity plays an important role in modulating the effects that a single bout of cardiovascular exercise has on the consolidation phase following motor skill learning. There appears to be a dose-response relationship in favour of higher intensity exercise in order to augment off-line effects and strengthen procedural memory.

  10. Effect of previous exhaustive exercise on metabolism and fatigue development during intense exercise in humans

    DEFF Research Database (Denmark)

    Iaia, F. M.; Perez-Gomez, J.; Nordsborg, Nikolai

    2010-01-01

    (HI; approximately 3 min) or low (LO; approximately 2 h) intensity. Compared with CON, performance during EX2 was reduced (P... during a repeated high-intensity exercise lasting 1/2-2 min.......The present study examined how metabolic response and work capacity are affected by previous exhaustive exercise. Seven subjects performed an exhaustive cycle exercise ( approximately 130%-max; EX2) after warm-up (CON) and 2 min after an exhaustive bout at a very high (VH; approximately 30 s), high...

  11. 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.

  12. Effects of exercise intensity and creatine loading on post-resistance exercise hypotension

    Directory of Open Access Journals (Sweden)

    Moreno Rodrigues Moreno

    2009-01-01

    Postexercise hypotension plays an important role in the non-pharmacological treat-ment of hypertension and is characterized by a decrease in blood pressure after a single exercise bout in relation to pre-exercise levels. This study investigated the effects of exercise intensity and creatine monohydrate supplementation on postexercise hypotension, as well as the possible role of blood lactate in this response. Ten normotensive subjects underwent resistance exercise sessions before (BC and after (AC creatine supplementation: 1 muscle endurance (ME consisting of 30 repetitions at 30% of one-repetition maximum; 2 hypertrophy (HP consisting of 8 repetitions at 75% of one-repetition maximum. Blood pressure was measured before and after the exercise bout. Blood lactate was measured after the exercise bout. The HP and ME sessions promoted a decrease in systolic blood pressure (∆ -19 ± 1.0 mmHg; ∆ -15 ± 0.9 mmHg, respectively, P 0.05. In conclusion, resistance exercise intensity did not influence postexercise hypotension. Creatine supplementation attenuated the decrease in blood pressure after resistance exercise. The results suggest the involvement of blood lactate in post-resistance exercise hypotension.

  13. Effects of exercise intensity and creatine loading on post-resistance exercise hypotension

    Directory of Open Access Journals (Sweden)

    Moreno Rodrigues Moreno

    2009-09-01

    Full Text Available Postexercise hypotension plays an important role in the non-pharmacological treat-ment of hypertension and is characterized by a decrease in blood pressure after a single exercise bout in relation to pre-exercise levels. This study investigated the effects of exercise intensity and creatine monohydrate supplementation on postexercise hypotension, as well as the possible role of blood lactate in this response. Ten normotensive subjects underwent resistance exercise sessions before (BC and after (AC creatine supplementation: 1 muscle endurance (ME consisting of 30 repetitions at 30% of one-repetition maximum; 2 hypertrophy (HP consisting of 8 repetitions at 75% of one-repetition maximum. Blood pressure was measured before and after the exercise bout. Blood lactate was measured after the exercise bout. The HP and ME sessions promoted a decrease in systolic blood pressure (∆ -19 ± 1.0 mmHg; ∆ -15 ± 0.9 mmHg, respectively, P 0.05. In conclusion, resistance exercise intensity did not influence postexercise hypotension. Creatine supplementation attenuated the decrease in blood pressure after resistance exercise. The results suggest the involvement of blood lactate in post-resistance exercise hypotension.

  14. 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

  15. Are gender differences in upper-body power generated by elite cross-country skiers augmented by increasing the intensity of exercise?

    Directory of Open Access Journals (Sweden)

    Ann Magdalen Hegge

    Full Text Available In the current study, we evaluated the impact of exercise intensity on gender differences in upper-body poling among cross-country skiers, as well as the associated differences in aerobic capacity, maximal strength, body composition, technique and extent of training. Eight male and eight female elite skiers, gender-matched for level of performance by FIS points, carried out a 4-min submaximal, and a 3-min and 30-sec maximal all-out test of isolated upper-body double poling on a Concept2 ski ergometer. Maximal upper-body power and strength (1RM were determined with a pull-down exercise. In addition, body composition was assessed with a DXA scan and training during the previous six months quantified from diaries. Relative to the corresponding female values (defined as 100%, the power output produced by the men was 88%, 95% and 108% higher during the submaximal, 3-min and 30-sec tests, respectively, and peak power in the pull-down strength exercise was 118% higher (all P<0.001. During the ergometer tests the work performed per cycle by the men was 97%, 102% and 91% greater, respectively, and the men elevated their cycle rate to a greater extent at higher intensities (both P<0.01. Furthermore, men had a 61% higher VO2peak, 58% higher 1RM, relatively larger upper-body mass (61% vs 56% and reported considerably more upper-body strength and endurance training (all P<0.05. In conclusion, gender differences in upper-body power among cross-country skiers augmented as the intensity of exercise increased. The gender differences observed here are greater than those reported previously for both lower- and whole-body sports and coincided with greater peak aerobic capacity and maximal upper-body strength, relatively more muscle mass in the upper-body, and more extensive training of upper-body strength and endurance among the male skiers.

  16. Protein modification responds to exercise intensity and antioxidant supplementation.

    Science.gov (United States)

    Lamprecht, Manfred; Oettl, Karl; Schwaberger, Guenther; Hofmann, Peter; Greilberger, Joachim F

    2009-01-01

    To assess the effects of different exercise intensities and antioxidant supplementation on plasma protein modification. Trained men (n = 41) from a homogenous population were randomly assigned to perform cycle ergometer exercise either at 70% or 80% of individual .VO2max. Each intensity group was randomly assigned to receive either juice powder concentrate (JPC 70%, n = 11; JPC 80%, n = 10) or placebo (Plac 70%, n = 10; Plac 80%, n = 10) capsules for 28 wk. Four controlled exercise bouts and blood collections were conducted at baseline and study weeks 4, 16, and 28. Blood samples were drawn before (BE), immediately after (IE), and 30 min (30M) and 30 h (30H) postexercise. These samples were analyzed to estimate concentrations of carbonyl groups on plasma proteins (CP) and the redox state of human serum albumin (HSA). In the Plac group, CP concentrations increased at 80% of .VO2max IE and 30M, returning to preexercise concentrations by 30H (P JPC groups (P JPC group had lower baseline CP levels after 16 and 28 wk and no exercise-induced CP increase. HSA is reversibly shifted to a more oxidized state by recent intense exercise.

  17. Impact of Mild versus Moderate Intensity Aerobic Walking Exercise ...

    African Journals Online (AJOL)

    Background: Patients with hemophilia A have low bone density than healthy controls. It is now widely recognized that physical activity and sports are beneficial for patients with hemophilia. Objective: The aim of this study was to compare the effects of mild and moderate intensity treadmill walking exercises on markers of ...

  18. Exercise intensity inferred from air consumption during recreational scuba diving.

    Science.gov (United States)

    Buzzacott, Peter; Pollock, Neal W; Rosenberg, Michael

    2014-06-01

    Episodic exercise is a risk factor for acute cardiac events and cardiac complications are increasingly recognized in fatalities during recreational scuba diving. What is not known is the exercise intensity involved in typical recreational diving. This study used pre- to post-dive gas cylinder pressure drop to estimate air consumption and, from that, exercise intensity during recreational dives. Dive profiles were captured electronically and divers self-reported cylinder pressure changes, perceived workload, thermal status and any problems during dives. Mean surface air consumption (SAC) rate per kg body weight and mean exercise intensity (reported in metabolic equivalents, MET multiples of assumed resting metabolic rate of 3.5 mL·kg⁻¹·min⁻¹) were then estimated. Data are reported as mean ± standard deviation. A total of 959 recreational air dives (20 ± 9 metres' sea water maximum depth; 50 ± 12 min underwater time) by 139 divers (42 ± 10 y age; 11 ± 10 y of diving; 12% smokers; 73% male) were monitored. Problems were reported with 129/959 dives: buoyancy (45%), equalization (38%), rapid ascent (10%), vertigo (5%) and other (2%). Assuming a 10% overestimate due to cylinder cooling and uncontrolled gas loss, the estimated exercise intensity associated with monitored dives was 5 ± 1 MET. Mean ± 2SD, or 7 MET, captures the effort associated with the vast majority of dives monitored. Our estimates suggest that uncomplicated recreational dives require moderate-intensity energy expenditure to complete, with a 7-MET capacity generally adequate. Higher levels of aerobic fitness are still strongly recommended to ensure ample reserves. Further research is needed to quantify energetic demands of recreational diving during both typical and emergent events in both experienced and less experienced divers.

  19. Exercise intensity progression for exercises performed on unstable and stable platforms based on ankle muscle activation.

    Science.gov (United States)

    Borreani, Sebastien; Calatayud, Joaquin; Martin, Julio; Colado, Juan Carlos; Tella, Victor; Behm, David

    2014-01-01

    Ankle sprains are a common sports injury. The literature focuses on the application of neuromuscular training for the improvement of balance, injury prevention and rehabilitation. However, there is a dearth of knowledge about the appropriate prescription of exercises using unstable platforms and surfaces. The purpose of this study was to devise an ankle rehabilitation or training program with exercise progression based on the extent of muscle activation, employing platforms with different levels of stability and additional resistance. A descriptive study of electromyography (EMG) during ankle exercises was performed with a convenience sample of healthy subjects. Forty-four subjects completed 12 exercises performed in a random order. Exercises were performed unipedally or bipedally with or without elastic tubing as resistance on various unstable (uncontrolled multiaxial and uniaxial movement) and stable surfaces. Surface EMG from the tibialis anterior (TA), peroneus longus (PL) and soleus (SOL) were collected to quantify the amount of muscle activity. Significant differences were found between exercise conditions for PL (pexercises for the ankle should progress from bilateral exercises on exercise balls (lowest intensity), to a unipedal position on a soft surface in combination with elastic tubing (highest intensity) in order to achieve progressively greater ankle muscle activation. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. 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.

  1. Decline in Executive Control during Acute Bouts of Exercise as a Function of Exercise Intensity and Fitness Level

    Science.gov (United States)

    Labelle, Veronique; Bosquet, Laurent; Mekary, Said; Bherer, Louis

    2013-01-01

    Studies on the effects of acute bouts of cardiovascular exercise on cognitive performances show contradictory findings due to methodological differences (e.g., exercise intensity, cognitive function assessed, participants' aerobic fitness level, etc.). The present study assessed the acute effect of exercise intensity on cognition while controlling…

  2. Muscle interstitial potassium kinetics during intense exhaustive exercise

    DEFF Research Database (Denmark)

    Nordsborg, Nikolai; Mohr, Magni; Pedersen, Lasse Dannemann

    2003-01-01

    Interstitial K+ ([K+]i) was measured in human skeletal muscle by microdialysis during exhaustive leg exercise, with (AL) and without (L) previous intense arm exercise. In addition, the reproducibility of the [K+]i determinations was examined. Possible microdialysis-induced rupture of the sarcolemma...... was assessed by measurement of carnosine in the dialysate, because carnosine is only expected to be found intracellularly. Changes in [K+]i could be reproduced, when exhaustive leg exercise was performed on two different days, with a between-day difference of approximately 0.5 mM at rest and 1.5 m......M at exhaustion. The time to exhaustion was shorter in AL than in L (2.7 +/- 0.3 vs. 4.0 +/- 0.3 min; P exhaustion (11.9 +/- 0.5 vs. 10.3 +/- 0.6 mM; P...

  3. Creatine kinase response to high-intensity aerobic exercise in adult-onset muscular dystrophy

    DEFF Research Database (Denmark)

    Andersen, Søren P; Sveen, Marie-Louise; Hansen, Regitze S

    2013-01-01

    We investigated the effect of high-intensity exercise on plasma creatine kinase (CK) in patients with muscular dystrophies.......We investigated the effect of high-intensity exercise on plasma creatine kinase (CK) in patients with muscular dystrophies....

  4. Intensive Exercise Training During Bed Rest Attenuates Deconditioning

    Science.gov (United States)

    Greenleaf, John E.

    1997-01-01

    Intensive exercise training during bed rest attenuates deconditioning. Med. Sci. Sports Exerc., Vol. 29, No. 2, pp. 207-215, 1997. A 30-d 6 deg head-down bed rest project was conducted to evaluate variable high-intensity, short-duration, isotonic cycle ergometer exercise (ITE) training and high-intensity intermittent resistive isokinetic exercise (IKE) training regimens designed to maintain peak VO2 and muscle mass, strength, and endurance at ambulatory control levels throughout prolonged bed rest. Other elements of the deconditioning (adaptive) syndrome, such as proprioception, psychological performance, hypovolemia, water balance, body composition, and orthostatic tolerance, were also measured. Major findings are summarized in this paper. Compared with response during bed rest of the no exercise (NOE) control group: the ITE training regimen (a) maintained work capacity (peak VO2), (b) maintained plasma and red cell volumes, (c) induced positive body water balance, (d) decreased quality of sleep and mental concentration, and (e) had no effect on the decrease in orthostatic tolerance; the IKE training regimen (f) attenuated the decrease in peak VO2 by 50%, (g) attenuated loss of red cell volume by 40% but had no effect on loss of plasma volume, (b) induced positive body water balance, (i) had no adverse effect on quality of sleep or concentration, and 0) had no effect on the decrease in orthostatic tolerance. These findings suggest that various elements of the deconditioning syndrome can be manipulated by duration and intensity of ITE or IKE training regimens and that several different training protocols will be required to maintain or restore physiological and psychological performance of individuals confined to prolonged bed rest.

  5. Effect of Different Exercise Intensities on the Myotendinous Junction Plasticity.

    Directory of Open Access Journals (Sweden)

    Davide Curzi

    Full Text Available Myotendinous junctions (MTJs are anatomical regions specialized in transmission of contractile strength from muscle to tendon and, for this reason, a common site where acute injuries occur during sport activities. In this work we investigated the influence of exercise intensity on MTJ plasticity, as well as on the expression of insulin-like growth factor 1 (IGF-1 and transforming growth factor beta (TGF-β and their receptors in muscle and tendon. Three groups of rats were analyzed: control (CTRL, slow-runner (RUN-S and fast-runner (RUN-F trained using a treadmill. Ultrastructural and morphometric analyses of distal MTJs from extensor digitorum longus muscles have been performed. Contractile strength and hypertrophy were investigated by using in vivo tension recordings and muscle cross-sectional area (CSA analysis, respectively. mRNA levels of PGC-1α, vinculin, IGF-1Ea and TGF-β have been quantified in muscle belly, while IGF-1Ea, TGF-β and their receptors in tendon. Morphometry revealed an increased MTJ complexity and interaction surface between tissues in trained rats according to training intensity. CSA analysis excluded hypertrophy among groups, while muscle strength was found significantly enhanced in exercised rats in comparison to controls. In muscle tissue, we highlighted an increased mRNA expression of PGC-1α and vinculin in both trained conditions and of TGF-β in RUN-F. In tendon, we mainly noted an enhancement of TGF-β mRNA expression only in RUN-F group and a raise of Betaglycan tendon receptor mRNA levels proportional to exercise intensity. In conclusion, MTJ plasticity appears to be related to exercise intensity and molecular analysis suggests a major role played by TGF-β.

  6. International exercise on {sup 124}Sb photon emission intensities determination

    Energy Technology Data Exchange (ETDEWEB)

    Be, M.-M., E-mail: mmbe@cea.f [Laboratoire National Henri Becquerel (LNE-LNHB), CEA, LIST, F 91191 Gif-sur-Yvette Cedex (France); Chauvenet, B.; Amiot, M.-N.; Bobin, C.; Lepy, M.-C.; Branger, T.; Laniece, I. [Laboratoire National Henri Becquerel (LNE-LNHB), CEA, LIST, F 91191 Gif-sur-Yvette Cedex (France); Luca, A.; Sahagia, M.; Waetjen, A.C. [Horia Hulubei, National Institute of Physics and Nuclear Engineering (IFIN-HH), P.O. Box MG-6, Bucharest (Romania); Kossert, K.; Ott, O.; Naehle, O. [Physikalisch Technische Bundesanstalt (PTB), Bundesallee 100, D 38116 Braunschweig (Germany); Dryak, P.; Sochorova, J.; Kovar, P.; Auerbach, P. [Czech Metrological Institute (CMI), Radiova 1, CZ 10200 Praha 10 (Czech Republic); Altzitzoglou, T.; Pomme, S.; Sibbens, G. [Institute for Reference Material and Measurements (IRMM), European Commission, Retieseweg 111, 2440 Geel (Belgium)

    2010-10-15

    An international exercise, registered as EUROMET project no. 907, was launched to measure both the activity of a solution of {sup 124}Sb and the photon emission intensities of its decay. The same solution was sent by LNE-LNHB to eight participating laboratories, six of which sent results for photon emission intensities both in absolute and in relative terms. From these results and including previous published values, a consistent decay scheme was worked out, proving that problems in activity measurements have not been due to decay scheme data.

  7. 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 ...

  8. 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 ...

  9. Influence of exercise intensity on respiratory muscle fatigue and brachial artery blood flow during cycling exercise.

    Science.gov (United States)

    Smith, Joshua R; Ade, Carl J; Broxterman, Ryan M; Skutnik, Benjamin C; Barstow, Thomas J; Wong, Brett J; Harms, Craig A

    2014-08-01

    During high intensity exercise, both respiratory muscle fatigue and cardiovascular reflexes occur; however, it is not known how inactive limb blood flow is influenced. The purpose of this study was to determine the influence of moderate and high exercise intensity on respiratory muscle fatigue and inactive limb muscle and cutaneous blood flow during exercise. Twelve men cycled at 70 and 85 % [Formula: see text] for 20 min. Subjects also performed a second 85 % [Formula: see text] test after ingesting 1,800 mg of N-acetylcysteine (NAC), which has been shown to reduce respiratory muscle fatigue (RMF). Maximum inspiratory pressures (P Imax), brachial artery blood flow (BABF), cutaneous vascular conductance (CVC), and mean arterial pressure were measured at rest and during exercise. Significant RMF occurred with 85 % [Formula: see text] (P Imax, -12.8 ± 9.8 %), but not with 70 % [Formula: see text] (P Imax, -5.0 ± 5.9 %). BABF and BA vascular conductance were significantly lower at end exercise of the 85 % [Formula: see text] test compared to the 70 % [Formula: see text] test. CVC during exercise was not different (p > 0.05) between trials. With NAC, RMF was reduced (p RMF, decreases in inactive arm blood flow, and vascular conductance, but not cutaneous blood flow.

  10. effect of a low-intensity resistance exercise programme with blood

    African Journals Online (AJOL)

    INTRODUCTION. Low-intensity resistance exercise with blood flow restriction can facilitate greater muscular ... studies have suggested that even low-intensity resistance exercise may have a positive effect on skeletal ..... Performance of high-intensity resistance exercise can result in acute changes in GH and IGF-. 1 plasma ...

  11. The influence of different exercise intensities on kicking accuracy and velocity in soccer players

    Directory of Open Access Journals (Sweden)

    Ricardo Ferraz

    2017-12-01

    Conclusion: These findings suggest that kicking ball velocity is influenced by high-exercise intensities. Low and moderate exercise intensities do not affect the performance of the kick, and intensity does not influence accuracy. Otherwise, it is possible that other mechanisms (not only physiological may influence players during the exercise.

  12. Acute exercise and motor memory consolidation: The role of exercise intensity and timing

    DEFF Research Database (Denmark)

    Thomas, Richard; Korsgaard Johnsen, Line; Geertsen, Svend Sparre

    2015-01-01

    Background A single bout of high intensity cycling (~90% VO2peak) immediately after motor skill training enhances motor memory consolidation. It is unclear how different parameters of exercise may influence this process and the underlying mechanisms are poorly understood. We hypothesize that the ...

  13. High-Intensity Interval Training Elicits Higher Enjoyment than Moderate Intensity Continuous Exercise.

    Directory of Open Access Journals (Sweden)

    Jacob S Thum

    Full Text Available Exercise adherence is affected by factors including perceptions of enjoyment, time availability, and intrinsic motivation. Approximately 50% of individuals withdraw from an exercise program within the first 6 mo of initiation, citing lack of time as a main influence. Time efficient exercise such as high intensity interval training (HIIT may provide an alternative to moderate intensity continuous exercise (MICT to elicit substantial health benefits. This study examined differences in enjoyment, affect, and perceived exertion between MICT and HIIT. Twelve recreationally active men and women (age = 29.5 ± 10.7 yr, VO2max = 41.4 ± 4.1 mL/kg/min, BMI = 23.1 ± 2.1 kg/m2 initially performed a VO2max test on a cycle ergometer to determine appropriate workloads for subsequent exercise bouts. Each subject returned for two additional exercise trials, performing either HIIT (eight 1 min bouts of cycling at 85% maximal workload (Wmax with 1 min of active recovery between bouts or MICT (20 min of cycling at 45% Wmax in randomized order. During exercise, rating of perceived exertion (RPE, affect, and blood lactate concentration (BLa were measured. Additionally, the Physical Activity Enjoyment Scale (PACES was completed after exercise. Results showed higher enjoyment (p = 0.013 in response to HIIT (103.8 ± 9.4 versus MICT (84.2 ± 19.1. Eleven of 12 participants (92% preferred HIIT to MICT. However, affect was lower (p<0.05 and HR, RPE, and BLa were higher (p<0.05 in HIIT versus MICT. Although HIIT is more physically demanding than MICT, individuals report greater enjoyment due to its time efficiency and constantly changing stimulus.NCT:02981667.

  14. High-Intensity Interval Training Elicits Higher Enjoyment than Moderate Intensity Continuous Exercise

    Science.gov (United States)

    Thum, Jacob S.; Parsons, Gregory; Whittle, Taylor

    2017-01-01

    Exercise adherence is affected by factors including perceptions of enjoyment, time availability, and intrinsic motivation. Approximately 50% of individuals withdraw from an exercise program within the first 6 mo of initiation, citing lack of time as a main influence. Time efficient exercise such as high intensity interval training (HIIT) may provide an alternative to moderate intensity continuous exercise (MICT) to elicit substantial health benefits. This study examined differences in enjoyment, affect, and perceived exertion between MICT and HIIT. Twelve recreationally active men and women (age = 29.5 ± 10.7 yr, VO2max = 41.4 ± 4.1 mL/kg/min, BMI = 23.1 ± 2.1 kg/m2) initially performed a VO2max test on a cycle ergometer to determine appropriate workloads for subsequent exercise bouts. Each subject returned for two additional exercise trials, performing either HIIT (eight 1 min bouts of cycling at 85% maximal workload (Wmax) with 1 min of active recovery between bouts) or MICT (20 min of cycling at 45% Wmax) in randomized order. During exercise, rating of perceived exertion (RPE), affect, and blood lactate concentration (BLa) were measured. Additionally, the Physical Activity Enjoyment Scale (PACES) was completed after exercise. Results showed higher enjoyment (p = 0.013) in response to HIIT (103.8 ± 9.4) versus MICT (84.2 ± 19.1). Eleven of 12 participants (92%) preferred HIIT to MICT. However, affect was lower (pHIIT versus MICT. Although HIIT is more physically demanding than MICT, individuals report greater enjoyment due to its time efficiency and constantly changing stimulus. Trial Registration: NCT:02981667. PMID:28076352

  15. Core stabilization exercises enhance lactate clearance following high-intensity exercise.

    Science.gov (United States)

    Navalta, James W; Hrncir, Stephen P

    2007-11-01

    Dynamic activities such as running, cycling, and swimming have been shown to effectively reduce lactate in the postexercise period. It is unknown whether core stabilization exercises performed following an intense bout would exhibit a similar effect. Therefore, this study was designed to assess the extent of the lactate response with core stabilization exercises following high-intensity anaerobic exercise. Subjects (N = 12) reported twice for testing, and on both occasions baseline lactate was obtained after 5 minutes of seated rest. Subjects then performed a 30-second Wingate anaerobic cycle test, immediately followed by a blood lactate sample. In the 5-minute postexercise period, subjects either rested quietly or performed core stabilization exercises. A final blood lactate sample was obtained following the 5-minute intervention period. Analysis revealed a significant interaction (p = 0.05). Lactate values were similar at rest (core = 1.4 +/- 0.1, rest = 1.7 +/- 0.2 mmol x L(-1)) and immediately after exercise (core = 4.9 +/- 0.6, rest = 5.4 +/- 0.4 mmol x L(-1)). However, core stabilization exercises performed during the 5-minute postexercise period reduced lactate values when compared to rest (5.9 +/- 0.6 vs. 7.6 +/- 0.8 mmol x L(-1)). The results of this study show that performing core stabilization exercises during a recovery period significantly reduces lactate values. The reduction in lactate may be due to removal via increased blood flow or enhanced uptake into the core musculature. Incorporation of core stability exercises into a cool-down period following muscular work may result in benefits to both lactate clearance as well as enhanced postural control.

  16. Exercise intensity and postprandial health outcomes in adolescents.

    Science.gov (United States)

    Bond, Bert; Williams, Craig A; Isic, Carly; Jackman, Sarah R; Tolfrey, Keith; Barrett, Laura A; Barker, Alan R

    2015-05-01

    The effect of exercise intensity and sex on postprandial risk factors for cardiovascular disease in adolescents is unknown. We examined the effect of a single bout of work-matched high-intensity interval exercise (HIIE) and moderate-intensity exercise (MIE) on postprandial triacylglycerol (TAG) and systolic blood pressure (SBP) in adolescents. Twenty adolescents (10 male, 14.3 ± 0.3 years) completed three 1-day trials: (1) rest (CON); (2) 8 × 1 min cycling at 90 % peak power with 75 s recovery (HIIE); (3) cycling at 90 % of the gas exchange threshold (MIE), 1 h before consuming a high-fat milkshake (1.50 g fat and 80 kJ kg(-1)). Postprandial TAG, SBP and fat oxidation were assessed over 4 h Compared to CON, the incremental area under the curve for TAG (IAUC-TAG) was not significantly lowered in HIIE [P = 0.22, effect size (ES) = 0.24] or MIE (P = 0.65, ES = 0.04) for boys. For girls, HIIE and MIE lowered IAUC-TAG by 34 % (P = 0.02, ES = 0.58) and 38 % (P = 0.09, ES = 0.73), respectively, with no difference between HIIE and MIE (P = 0.74, ES = 0.14). Changes in TAG were not related to energy expenditure during exercise or postprandial fat oxidation. Postprandial SBP (total-AUC pooled for both sexes) was lower in HIIE compared to CON (P = 0.01, ES = 0.68) and MIE (P = 0.02, ES = 0.60), with no difference between MIE and CON (P = 0.45, ES = 0.14). A single bout of HIIE and MIE, performed 1 h before an HFM, can meaningfully attenuate IAUC-TAG in girls but not boys. Additionally, HIIE, but not MIE, may lower postprandial SBP in normotensive adolescents.

  17. Sweating away depression? The impact of intensive exercise on depression.

    Science.gov (United States)

    Balchin, Ross; Linde, Jani; Blackhurst, Dee; Rauch, Hg Laurie; Schönbächler, Georg

    2016-08-01

    In periods of prolonged stress and pain the body produces endorphins to help endure pain. The PANIC system is built on the same pathways as the pain system and is characterized by behaviour that looks like depression. The term 'mental pain' in the context of feelings of loss is arguably justified in light of this relationship between the physical pain and social loss systems. It is reasonable to expect that endorphin release ameliorates depression. Moderately depressed males (n=30) were randomly assigned to one of three groups of varying exercise intensity. Each underwent a six-week exercise programme for three days per week, one hour per day. The HAM-D, MADRS, and ANPS were administered weekly and β-endorphin levels measured. Moderate- and high-intensity exercise improved depression levels, while very-low intensity exercise did not have as beneficial an effect. β-endorphin results were inconclusive. Participants showed a slight decrease in PANIC and FEAR, and increased SEEKING. The potential insensitivity of the assays that were utilized, and the known problems with measuring β-endorphins, may have contributed to the findings. The lack of a state measure of the basic emotion systems is problematic, as a trait measure has to be relied upon, and this likely affected the ability to accurately detect changes over time. The demonstrated improvements in depressive symptoms have important implications for the clinical treatment of patients despite the hypothesis that the PANIC system is involved in the genesis and maintenance of depression not having been conclusively confirmed. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Exercise motivation: a cross-sectional analysis examining its relationships with frequency, intensity, and duration of exercise

    Directory of Open Access Journals (Sweden)

    Wilson Philip M

    2010-01-01

    Full Text Available Abstract Background It is important to engage in regular physical activity in order to maintain a healthy lifestyle however a large portion of the population is insufficiently active. Understanding how different types of motivation contribute to exercise behavior is an important first step in identifying ways to increase exercise among individuals. The current study employs self-determination theory as a framework from which to examine how motivation contributes to various characteristics of exercise behavior. Methods Regular exercisers (N = 1079; n = 468 males; n = 612 females completed inventories which assessed the frequency, intensity, and duration with which they exercise, as well as the Behavioral Regulation in Exercise Questionnaire including four additional items assessing integrated regulation. Results Bivariate correlations revealed that all three behavioral indices (frequency, intensity, and duration of exercise were more highly correlated with more autonomous than controlling regulations. Regression analyses revealed that integrated and identified regulations predicted exercise frequency for males and females. Integrated regulation was found to be the only predictor of exercise duration across both genders. Finally, introjected regulation predicted exercise intensity for females only. Conclusions These findings suggest that exercise regulations that vary in their degree of internalization can differentially predict characteristics of exercise behavior. Furthermore, in the motivational profile of a regular exerciser, integrated regulation appears to be an important determinant of exercise behavior. These results highlight the importance of assessing integrated regulation in exercise settings where the goal of understanding motivated behavior has important health implications.

  19. 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.)

  20. Oxidative stress and antioxidant responses to progressive resistance exercise intensity in trained and untrained males

    OpenAIRE

    H Çakır-Atabek; F. Özdemir; Çolak, R.

    2015-01-01

    The relationship between oxidative stress and some exercise components of resistance exercise (e.g. intensity, exercise volume) has not been clearly defined. Additionally, the oxidative stress markers may respond differently in various conditions. This study aims to determine the effects of progressive intensity of resistance exercise (RE) on oxidative stress and antioxidants in trained and untrained men, and also to investigate the possible threshold intensity required to evoke oxidative str...

  1. Acute Exercise-Associated Skin Surface Temperature Changes after Resistance Training with Different Exercise Intensities

    Directory of Open Access Journals (Sweden)

    Martin Weigert

    2018-01-01

    Full Text Available Background: Studies showed, that changes in muscular metabolic-associated heat production and blood circulation during and after muscular work affect skin temperature (T but the results are inconsistent and the effect of exercise intensity is unclear. Objective: This study investigated the intensity-dependent reaction of T on resistance training. Methods: Ten male students participated. After acclimatization (15 min, the participants completed 3x10 repetitions of unilateral biceps curl with 30, 50 or 70% of their one-repetition-maximum (1RM in a randomized order. Skin temperature of the loaded and unloaded biceps was measured at rest (Trest, immediately following set 1, 2 and 3 (TS1,TS2,TS3 and 30 minutes post exercise (T1 - T30 with an infrared camera. Results: Two-way ANOVA detected a significant effect of the measuring time point on T (Trest to T30 of the loaded arm for 30% (Eta²=0.85, 50% (Eta²=0.88 and 70% 1RM (Eta²=0.85 and of the unloaded arm only for 30% 1RM (Eta²=0.41 (p0.05. The T values at the different measuring time points (Trest - T30 did not differ between the intensities at any time point. The loaded arm showed a mean maximum T rise to Trest of 1.8°C and on average, maximum T was reached approximately 5 minutes after the third set.  Conclusion: This study indicate a rise of T, which could be independent of the exercise intensity. Infrared thermography seems to be applicable to identify the primary used functional muscles in resistance training but this method seems not suitable to differentiate between exercise intensity from 30 to 70% 1RM.

  2. Intermittent intense exercise protects against cognitive decline in a similar manner to moderate exercise in chronically stressed mice.

    Science.gov (United States)

    Lee, Hyunjin; Nagata, Kazufumi; Nakajima, Sanae; Ohno, Makoto; Ohta, Shigeo; Mikami, Toshio

    2018-01-18

    It is well known that regular low or mild exercise helps to improve and maintain cognition. On the other hand, ever thought many people prefer high-intensity exercise (e.g., running, swimming, biking, soccer, basketball, etc.) to get rid of stress or improve their health, the previous studies reported that intense exercise either impairs cognition or has no effect on cognitive function. However, we previously showed that intermittent intense exercise prevents stress-induced depressive behavior in mice in a similar manner to moderate exercise. On the basis of this finding, we investigated the effect of intermittent intense exercise on cognitive deficit in chronically stressed mice. A total of forty mice were evenly divided into control, stressed, stressed with moderate exercise, and stressed with intense exercise groups. The stressed mice were chronically exposed a restraint stress (10 h/day, 6 days/week for 7 weeks). The exercised mice were subjected to intermittent intense or endurance moderate running on the treadmill three times a week. Cognition was evaluated using the Morris water maze test and the object recognition test. Chronic stress decreased cognition, and newborn cell survival and blood vessel density in the hippocampus. However, both regular intense and moderate exercise prevented decrease of cognition, improved newborn cell survival and blood vessel density. These findings suggest that intermittent intense exercise may protect against decrease of cognition in a similar manner to moderate exercise and that both exercise-induced protection of decrease of cognition is closely related to newborn cell survival and angiogenesis in the hippocampus. Copyright © 2018. Published by Elsevier B.V.

  3. The Effects of Electrostimulation and Core Exercises on Recovery After High-Intensity Exercise

    Directory of Open Access Journals (Sweden)

    Ahmet Mor

    2017-12-01

    Full Text Available Introduction and objectives: The purpose of this study was to determine the effects of electrostimulation and core exercises on recovery after high-intensity exercise. Methods: The participants of this study consists of 12 male bodybuilders who regularly train and between the ages 18-30. Tabata high intensity interval training (HIIT was applied with different recovery methods to the athletes on three different days and the recovery levels of athletes were analysed. Heart rate and blood lactate levels were measured at baseline (PRE at immediately after the HIIT (POST, at the 1 minutes after HIIT (1min, at the 5 minutes after HIIT (5min, and at the 10 minutes after HIIT (10min. On the rest days, serum lactate dehydrogenase (LDH and serum creatine kinase (CK  measurements were done to determine the muscle damage. Results: The in-group comparisons for lactate levels showed no significant difference (p>0,01. The level of lactate on the 10min was found to be significantly lower than the 5min in the core exercise group (p0,01. These results show that the lactate level reaches to the maximum level after HIIT, and the level of lactate decreases between the 5th and the 10th minutes. Discussion and conclusion: These indicate that the active recovery methods are more effective than the passive. It was found that the active recovery methods accelerate the lactate removal from the metabolism and provide effective recovery in short time during the recovery period after exercise.

  4. Effects of exercise intensity and duration on nocturnal heart rate variability and sleep quality.

    Science.gov (United States)

    Myllymäki, Tero; Rusko, Heikki; Syväoja, Heidi; Juuti, Tanja; Kinnunen, Marja-Liisa; Kyröläinen, Heikki

    2012-03-01

    Acute physical exercise may affect cardiac autonomic modulation hours or even days during the recovery phase. Although sleep is an essential recovery period, the information on nocturnal autonomic modulation indicated by heart rate variability (HRV) after different exercises is mostly lacking. Therefore, this study investigated the effects of exercise intensity and duration on nocturnal HR, HRV, HR, and HRV-based relaxation, as well as on actigraphic and subjective sleep quality. Fourteen healthy male subjects (age 36 ± 4 years, maximal oxygen uptake 49 ± 4 ml/kg/min) performed five different running exercises on separate occasions starting at 6 p.m. with HR guidance at home. The effect of intensity was studied with 30 min of exercises at intensities corresponding to HR level at 45% (easy), 60% (moderate) and 75% (vigorous) of their maximal oxygen uptake. The effect of duration was studied with 30, 60, and 90 min of moderate exercises. Increased exercise intensity elevated nocturnal HR compared to control day (p exercises (p exercise day compared to control day (p exercise intensity nor duration had any impact on actigraphic or subjective sleep quality. The results suggest that increased exercise intensity and/or duration cause delayed recovery of nocturnal cardiac autonomic modulation, although long exercise duration was needed to induce changes in nocturnal HRV. Increased exercise intensity or duration does not seem to disrupt sleep quality.

  5. Effects of Different Intensities of Endurance Exercise in Morning and Evening on the Lipid Metabolism Response

    Science.gov (United States)

    Kim, Hyeon-Ki; Ando, Karina; Tabata, Hiroki; Konishi, Masayuki; Takahashi, Masaki; Nishimaki, Mio; Xiang, Mi; Sakamoto, Shizuo

    2016-01-01

    To study the effects of different exercise intensity performed at different exercise times on lipid metabolism response during prolonged exercise. Nine young men performed endurance exercise at different exercise intensities (60%VO2max or Fatmax) in the morning (9 am to 10 am) or evening (5 pm to 6 pm); blood samples were collected before exercise and immediately and one and two hours after exercise completion. Expired gas was analyzed from the start of exercise until two hours after exercise completion. There were no significant changes in catecholamine (adrenaline and noradrenaline) and free fatty acid levels between morning and evening trials for each endurance exercise intensity. However, the morning and evening trials both exhibited significantly higher lipid oxidation at Fatmax than that at 60%VO2max. These results suggest that exercise at Fatmax offers greater lipid oxidation than that at 60%VO2max, regardless of exercise timing. Key points It is important to consider exercise intensity when evaluating lipid oxidation. Few studies have investigated the effects of the intensity of exercise on lipid oxidation in the morning and evening. Fatmax exhibited greater total lipid oxidation compared to that of 60%VO2max when energy expenditure was equated, but time of day did not affect lipid oxidation in prolonged exercise. PMID:27803625

  6. Impact of a personalized versus moderate-intensity exercise prescription: a randomized controlled trial.

    Science.gov (United States)

    Schneider, Margaret; Schmalbach, Priel; Godkin, Sophia

    2017-04-01

    Effective approaches to promote adolescent physical activity are needed. Moreover, a one-size-fits-all approach has been minimally successful to date. This randomized controlled trial evaluates a theory-based personalized exercise prescription to enhance motivation for being active and physical activity participation among adolescent reluctant exercisers. Adolescents were characterized by affective style as reluctant (predisposed to negative affect during exercise) or latent (predisposed to positive affect during exercise) exercisers based on their affective response to an acute exercise task, and then randomly assigned to an exercise prescription of either a personalized or a moderate intensity. Assignment was double-blind. Assessments were pre- and post- the 8-week intervention. Participants were an ethnically diverse group of adolescents (19 % non-Latino White) in a public middle-school. The exercise intensity manipulation and assessments took place at the school site during regular Physical Education. Participants were assigned to either a moderate-intensity exercise prescription [target heart rate (HR) range 60-80 % of HR max] or a personalized exercise prescription corresponding to an intensity that "feels good" to the individual for 8 weeks during daily Physical Education. Outcome measures included exercise-related intrinsic motivation (via questionnaire), and daily moderate-to-vigorous physical activity (MVPA; via accelerometer). The exercise intensity manipulation did not yield actual differences in exercise intensity during PE, and had no effect on either Intrinsic Motivation or MVPA. There was no significant interaction between affective style and group assignment in predicting Intrinsic Motivation or MVPA. This study did not find support for a link between affective experiences during exercise and physical activity participation. Providing adolescents with a personalized exercise intensity prescription and asking them to follow the prescription

  7. Ergogenic effects of caffeine and sodium bicarbonate supplementation on intermittent exercise performance preceded by intense arm cranking exercise

    DEFF Research Database (Denmark)

    Marriott, Matthaus; Krustrup, Peter; Mohr, Magni

    2015-01-01

    BACKGROUND: Caffeine and sodium bicarbonate ingestion have been suggested to improve high-intensity intermittent exercise, but it is unclear if these ergogenic substances affect performance under provoked metabolic acidification. To study the effects of caffeine and sodium bicarbonate on intense...... to CAF and PLA, while no difference in heart rate was observed between trials. CONCLUSIONS: Caffeine and sodium bicarbonate administration improved Yo-Yo IR2 performance and lowered perceived exertion after intense arm cranking exercise, with greater overall effects of sodium bicarbonate intake....... intermittent exercise performance and metabolic markers under exercise-induced acidification, intense arm-cranking exercise was performed prior to intense intermittent running after intake of placebo, caffeine and sodium bicarbonate. METHODS: Male team-sports athletes (n = 12) ingested sodium bicarbonate (Na...

  8. Heart rate recovery and heart rate variability are unchanged in patients with coronary artery disease following 12 weeks of high-intensity interval and moderate-intensity endurance exercise training.

    Science.gov (United States)

    Currie, Katharine D; Rosen, Lee M; Millar, Philip J; McKelvie, Robert S; MacDonald, Maureen J

    2013-06-01

    Decreased heart rate variability and attenuated heart rate recovery following exercise are associated with an increased risk of mortality in cardiac patients. This study investigated the effects of 12 weeks of moderate-intensity endurance exercise (END) and a novel low-volume high-intensity interval exercise protocol (HIT) on measures of heart rate recovery and heart rate variability in patients with coronary artery disease (CAD). Fourteen males with CAD participated in 12 weeks of END or HIT training, each consisting of 2 supervised exercise sessions per week. END consisted of 30-50 min of continuous cycling at 60% peak power output (PPO). HIT involved ten 1-min intervals at 88% PPO separated by 1-min intervals at 10% PPO. Heart rate recovery at 1 min and 2 min was measured before and after training (pre- and post-training, respectively) using a submaximal exercise bout. Resting time and spectral and nonlinear domain measures of heart rate variability were calculated. Following 12 weeks of END and HIT, there was no change in heart rate recovery at 1 min (END, 40 ± 12 beats·min(-1) vs. 37 ± 19 beats·min(-1); HIT, 31 ± 8 beats·min(-1) vs. 35 ± 8 beats·min(-1); p ≥ 0.05 for pre- vs. post-training) or 2 min (END, 44 ± 18 beats·min(-1) vs. 43 ± 19 beats·min(-1); HIT, 42 ± 10 beats·min(-1) vs. 50 ± 6 beats·min(-1); p ≥ 0.05 for pre- vs. post-training). All heart rate variability indices were unchanged following END and HIT training. In conclusion, neither END nor HIT exercise programs elicited training-induced improvements in cardiac autonomic function in patients with CAD. The absence of improvements with training may be attributed to the optimal medical management and normative pretraining state of our sample.

  9. Effect of high-intensity interval exercise on basal triglyceride metabolism in non-obese men

    National Research Council Canada - National Science Library

    Bellou, Elena; Magkos, Faidon; Kouka, Tonia; Bouchalaki, Eirini; Sklaveniti, Dimitra; Maraki, Maria; Tsekouras, Yiannis E; Panagiotakos, Demosthenes B; Kavouras, Stavros A; Sidossis, Labros S

    2013-01-01

    A single bout of high-intensity interval aerobic exercise has been shown to produce the same or greater metabolic benefits as continuous endurance exercise with considerably less energy expenditure...

  10. 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.

  11. Intense Exercise in Type 1 Diabetes: Exploring the Role of Continuous Glucose Monitoring

    OpenAIRE

    Chassin, Ludovic Jean; Wilinska, Malgorzata E.; Hovorka, Roman

    2007-01-01

    Development of the external artificial pancreas (AP) is anticipated to be incremental, starting with simple and progressing to more complex applications incorporating exercise periods of various duration and intensity. Most studies investigating the effect of exercise on glucose excursions in subjects with type 1 diabetes either explored moderate exercise, which exerts different effects compared to intense exercise, or did not adopt continuous glucose monitoring combined with frequent plasma ...

  12. High-intensity training versus traditional exercise interventions for promoting health

    DEFF Research Database (Denmark)

    Nybo, Lars; Sundstrup, Emil; Jakobsen, Markus D

    2010-01-01

    The purpose of this study was to determine the effectiveness of brief intense interval training as exercise intervention for promoting health and to evaluate potential benefits about common interventions, that is, prolonged exercise and strength training.......The purpose of this study was to determine the effectiveness of brief intense interval training as exercise intervention for promoting health and to evaluate potential benefits about common interventions, that is, prolonged exercise and strength training....

  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. Intensity of swimming exercise influences aortic reactivity in rats

    Directory of Open Access Journals (Sweden)

    A.F. Brito

    2015-11-01

    Full Text Available Exercise is known to cause a vasodilatory response; however, the correlation between the vasorelaxant response and different training intensities has not been investigated. Therefore, this study evaluated the vascular reactivity and lipid peroxidation after different intensities of swimming exercise in rats. Male Wistar rats (aged 8 weeks; 250-300 g underwent forced swimming for 1 h whilst tied to loads of 3, 4, 5, 6, and 8% of their body weight, respectively (groups G3, G4, G5, G6 and G8, respectively; n=5 each. Immediately after the test, the aorta was removed and suspended in an organ bath. Cumulative relaxation in response to acetylcholine (10−12-10−4 M and contraction in response to phenylephrine (10−12-10−5 M were measured. Oxidative stress was estimated by determining malondialdehyde concentration. The percentages of aorta relaxation were significantly higher in G3 (7.9±0.20, G4 (7.8±0.29, and G5 (7.9±0.21, compared to the control group (7.2±0.04, while relaxation in the G6 (7.4±0.25 and G8 (7.0±0.06 groups was similar to the control group. In contrast, the percentage of contraction was significantly higher in G6 (8.8 ±0.1 and G8 (9.7±0.29 compared to the control (7.1±0.1, G3 (7.3±0.2, G4 (7.2±0.1 and G5 (7.2±0.2% groups. Lipid peroxidation levels in the aorta were similar to control levels in G3, G4 and G5, but higher in G6 and G8, and significantly higher in G8 (one-way ANOVA. These results indicate a reduction in vasorelaxing activity and an increase in contractile activity in rat aortas after high-intensity exercise, followed by an increase in lipid peroxidation.

  15. Short-term high-intensity interval and continuous moderate-intensity training improve maximal aerobic power and diastolic filling during exercise.

    Science.gov (United States)

    Esfandiari, Sam; Sasson, Zion; Goodman, Jack M

    2014-02-01

    This study examined the effects of short-term high-intensity interval training (HIT) and continuous moderate-intensity training (CMT) on cardiac function in young, healthy men. Sixteen previously untrained men (mean age of 25.1 ± 4.1 years) were randomly assigned to HIT and CMT (n = 8 each) and assessed before and after six sessions over a 12-day training period. HIT consisted of 8-12 intervals of cycling for 60 s at 95-100% of pre-training maximal aerobic power (VO(2max)), interspersed by 75 s of cycling at 10% VO(2max). CMT involved 90-120 min of cycling at 65% pre-training VO(2max). Left ventricular (LV) function was determined at rest and during submaximal exercise (heart rate ~105 bpm) using two-dimensional and Doppler echocardiography. Training resulted in increased calculated plasma volume (PV) in both groups, accompanied by improved VO(2max) in HIT (HIT: from 39.5 ± 7.1 to 43.9 ± 5.5 mL kg(-1) min(-1); CMT: from 39.9 ± 5.9 to 41.7 ± 5.3 mL kg(-1) min(-1); P volume (P = 0.02) and cardiac output (P = 0.02) were observed, secondary to increases in end-diastolic volume (P training groups and were related to changes in PV. Short-term HIT and CMT elicit rapid improvements in VO2max and LV filling without global changes in cardiac performance at rest.

  16. Alterations in Aerobic Exercise Performance and Gait Economy Following High-Intensity Dynamic Stepping Training in Persons With Subacute Stroke.

    Science.gov (United States)

    Leddy, Abigail L; Connolly, Mark; Holleran, Carey L; Hennessy, Patrick W; Woodward, Jane; Arena, Ross A; Roth, Elliot J; Hornby, T George

    2016-10-01

    Impairments in metabolic capacity and economy (O2cost) are hallmark characteristics of locomotor dysfunction following stroke. High-intensity (aerobic) training has been shown to improve peak oxygen consumption in this population, with fewer reports of changes in O2cost. However, particularly in persons with subacute stroke, inconsistent gains in walking function are observed with minimal associations with gains in metabolic parameters. The purpose of this study was to evaluate changes in aerobic exercise performance in participants with subacute stroke following high-intensity variable stepping training as compared with conventional therapy. A secondary analysis was performed on data from a randomized controlled trial comparing high-intensity training with conventional interventions, and from the pilot study that formed the basis for the randomized controlled trial. Participants 1 to 6 months poststroke received 40 or fewer sessions of high-intensity variable stepping training (n = 21) or conventional interventions (n = 12). Assessments were performed at baseline (BSL), posttraining, and 2- to 3-month follow-up and included changes in submaximal (Equation is included in full-text article.)O2 ((Equation is included in full-text article.)O2submax) and O2cost at fastest possible treadmill speeds and peak speeds at BSL testing. Significant improvements were observed in (Equation is included in full-text article.)O2submax with less consistent improvements in O2cost, although individual responses varied substantially. Combined changes in both (Equation is included in full-text article.)O2submax and (Equation is included in full-text article.)O2 at matched peak BSL speeds revealed stronger correlations to improvements in walking function as compared with either measure alone. High-intensity stepping training may elicit significant improvements in (Equation is included in full-text article.)O2submax, whereas changes in both peak capacity and economy better reflect gains

  17. Data on mitochondrial function in skeletal muscle of old mice in response to different exercise intensity

    OpenAIRE

    Kang, Chounghun; Lim, Wonchung

    2016-01-01

    Endurance exercise is securely linked to muscle metabolic adaptations including enhanced mitochondrial function (?Effects of exercise on mitochondrial oxygen uptake and respiratory enzyme activity in skeletal muscle? [1], ?Effects of exercise on mitochondrial content and function in aging human skeletal muscle? [2]). However, the link between exercise intensity and mitochondrial function in aging muscle has not been fully investigated. In order to understand how strenuous exercise affects mit...

  18. 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

  19. 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.

  20. PGC-1α and exercise intensity dependent adaptations in mouse skeletal muscle.

    Directory of Open Access Journals (Sweden)

    Nina Brandt

    Full Text Available The aim of the present study was to examine the role of PGC-1α in intensity dependent exercise and exercise training-induced metabolic adaptations in mouse skeletal muscle. Whole body PGC-1α knockout (KO and littermate wildtype (WT mice performed a single treadmill running bout at either low intensity (LI for 40 min or moderate intensity (MI for 20 min. Blood and quadriceps muscles were removed either immediately after exercise or at 3h or 6h into recovery from exercise and from resting controls. In addition PGC-1α KO and littermate WT mice were exercise trained at either low intensity (LIT for 40 min or at moderate intensity (MIT for 20 min 2 times pr. day for 5 weeks. In the first and the last week of the intervention period, mice performed a graded running endurance test. Quadriceps muscles were removed before and after the training period for analyses. The acute exercise bout elicited intensity dependent increases in LC3I and LC3II protein and intensity independent decrease in p62 protein in skeletal muscle late in recovery and increased LC3II with exercise training independent of exercise intensity and volume in WT mice. Furthermore, acute exercise and exercise training did not increase LC3I and LC3II protein in PGC-1α KO. In addition, exercise-induced mRNA responses of PGC-1α isoforms were intensity dependent. In conclusion, these findings indicate that exercise intensity affected autophagy markers differently in skeletal muscle and suggest that PGC-1α regulates both acute and exercise training-induced autophagy in skeletal muscle potentially in a PGC-1α isoform specific manner.

  1. 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.

  2. Data on mitochondrial function in skeletal muscle of old mice in response to different exercise intensity

    Directory of Open Access Journals (Sweden)

    Chounghun Kang

    2016-06-01

    Full Text Available Endurance exercise is securely linked to muscle metabolic adaptations including enhanced mitochondrial function (“Effects of exercise on mitochondrial oxygen uptake and respiratory enzyme activity in skeletal muscle” [1], “Effects of exercise on mitochondrial content and function in aging human skeletal muscle” [2]. However, the link between exercise intensity and mitochondrial function in aging muscle has not been fully investigated. In order to understand how strenuous exercise affects mitochondrial function in aged mice, male C57BL/6 mice at age 24 months were randomly assigned to 3 groups: non-exercise (NE, low-intensity (LE and high-intensity treadmill exercise group (HE. Mitochondrial complex activity and respiration were measured to evaluate mitochondrial function in mouse skeletal muscle. The data described here are related to the research article entitled “Strenuous exercise induces mitochondrial damage in skeletal muscle of old mice” [3].

  3. Data on mitochondrial function in skeletal muscle of old mice in response to different exercise intensity.

    Science.gov (United States)

    Kang, Chounghun; Lim, Wonchung

    2016-06-01

    Endurance exercise is securely linked to muscle metabolic adaptations including enhanced mitochondrial function ("Effects of exercise on mitochondrial oxygen uptake and respiratory enzyme activity in skeletal muscle" [1], "Effects of exercise on mitochondrial content and function in aging human skeletal muscle" [2]). However, the link between exercise intensity and mitochondrial function in aging muscle has not been fully investigated. In order to understand how strenuous exercise affects mitochondrial function in aged mice, male C57BL/6 mice at age 24 months were randomly assigned to 3 groups: non-exercise (NE), low-intensity (LE) and high-intensity treadmill exercise group (HE). Mitochondrial complex activity and respiration were measured to evaluate mitochondrial function in mouse skeletal muscle. The data described here are related to the research article entitled "Strenuous exercise induces mitochondrial damage in skeletal muscle of old mice" [3].

  4. The Effects of Exercise Intensity vs. Metabolic State on the Variability and Magnitude of Left Ventricular Twist Mechanics during Exercise.

    Directory of Open Access Journals (Sweden)

    Craig Armstrong

    Full Text Available Increased left ventricular (LV twist and untwisting rate (LV twist mechanics are essential responses of the heart to exercise. However, previously a large variability in LV twist mechanics during exercise has been observed, which complicates the interpretation of results. This study aimed to determine some of the physiological sources of variability in LV twist mechanics during exercise. Sixteen healthy males (age: 22 ± 4 years, [Formula: see text]O2peak: 45.5 ± 6.9 ml∙kg-1∙min-1, range of individual anaerobic threshold (IAT: 32-69% of [Formula: see text]O2peak were assessed at rest and during exercise at: i the same relative exercise intensity, 40%peak, ii at 2% above IAT, and, iii at 40%peak with hypoxia (40%peak+HYP. LV volumes were not significantly different between exercise conditions (P > 0.05. However, the mean margin of error of LV twist was significantly lower (F2,47 = 2.08, P 0.05. Overall, LV twist mechanics were linearly related to rate pressure product. During exercise, the intra-individual variability of LV twist mechanics is smaller at the same relative exercise intensity compared with IAT. However, the absolute magnitude (degrees of LV twist mechanics appears to be associated with the prevailing rate pressure product. Exercise tests that evaluate LV twist mechanics should be standardised by relative exercise intensity and rate pressure product be taken into account when interpreting results.

  5. Glucocorticoids improve high-intensity exercise performance in humans

    DEFF Research Database (Denmark)

    Casuso, Rafael A; Melskens, Lars; Bruhn, Thomas

    2014-01-01

    It was investigated whether oral dexamethasone (DEX) administration improves exercise performance by reducing the initial rate of muscle fatigue development during dynamic exercise.......It was investigated whether oral dexamethasone (DEX) administration improves exercise performance by reducing the initial rate of muscle fatigue development during dynamic exercise....

  6. The effect of exercise intensity on cognitive performance during short duration treadmill running

    Directory of Open Access Journals (Sweden)

    Smith Mike

    2016-06-01

    Full Text Available This study examined the effect of short duration, moderate and high-intensity exercise on a Go/NoGo task. Fifteen, habitually active (9 females and 6 males aged 28 ± 5 years agreed to participate in the study and cognitive performance was measured in three sessions lasting 10 min each, performed at three different exercise intensities: rest, moderate and high. Results indicated significant exercise intensity main effects for reaction time (RT (p = 0.01, the omission error rate (p = 0.027 and the decision error rate (p = 0.011, with significantly longer RTs during high intensity exercise compared to moderate intensity exercise (p = 0.039 and rest (p = 0.023. Mean ± SE of RT (ms was 395.8 ± 9.1, 396.3 ± 9.1 and 433.5 ± 16.1 for rest, moderate and high intensity exercise, respectively. This pattern was replicated for the error rate with a significantly higher omission error and decision error rate during high intensity exercise compared to moderate intensity exercise (p = 0.003 and rest (p = 0.001. Mean ± SE of omission errors (% was 0.88 ± 0.23, 0.8 ± 0.23 and 1.8 ± 0.46% for rest, moderate and high intensity exercise, respectively. Likewise, mean ± SE of decision errors (% was 0.73 ± 0.24, 0.73 ± 0.21 and 1.8 ± 0.31 for rest, moderate and high intensity exercise, respectively. The present study’s results suggest that 10 min workout at high intensity impairs RT performances in habitually active adults compared to rest or moderate intensity exercise.

  7. The talk test: a useful tool for prescribing and monitoring exercise intensity.

    Science.gov (United States)

    Reed, Jennifer L; Pipe, Andrew L

    2014-09-01

    This review focuses on recent literature examining the validity and reliability of the talk test for prescribing and monitoring exercise intensity. The utility of the talk test for high-intensity interval training and recently proposed exercise training guidelines for patients with atrial fibrillation is also examined. In healthy adults and patients with cardiovascular disease, comfortable speech is likely possible (equivocal or last positive talk test stage) when exercise intensity is below the ventilatory or lactate threshold, and not likely possible (negative talk test stage) when exercise intensity exceeds the ventilatory or lactate threshold. The talk test can be used to produce exercise intensities (moderate-to-vigorous intensity, 40-80% (Equation is included in full-text article.)) within accepted Canadian Association of Cardiovascular Prevention and Rehabilitation and American College of Sports Medicine guidelines for exercise training, to monitor exercise training for patients with atrial fibrillation, and help avoid exertional ischemia. The talk test has been shown to be consistent across various modes of exercise (i.e., walking, jogging, cycling, elliptical trainer and stair stepper). It may not be practical for high-intensity interval training. The talk test is a valid, reliable, practical and inexpensive tool for prescribing and monitoring exercise intensity in competitive athletes, healthy active adults and patients with cardiovascular disease. Healthcare professionals should feel comfortable in advocating its use in a variety of clinical and health-promotion settings.

  8. Correlation of gas exchange threshold and first muscle oxyhemoglobin inflection point with time-to-exhaustion during heavy-intensity exercise.

    Science.gov (United States)

    Coquart, Jérémy B; Mucci, Patrick; L'hermette, Maxime; Chamari, Karim; Tourny, Claire; Garcin, Murielle

    2017-03-01

    The twofold aim of the study was to: 1) compare the gas exchange threshold (GET), the first oxyhemoglobin inflection point ([O2Hb]-T), and perceptual threshold as determined during an incremental exercise test, and 2) investigate the link between each threshold and time-to-exhaustion during heavy intensity exercise. Fourteen competitive cyclists performed an incremental exercise test to exhaustion on a cycloergometer to determine the different thresholds and peak workload (Wpeak). The participants then performed a sub-maximal constant workload test (90% Wpeak) to exhaustion to determine time-to-exhaustion. The thresholds were identified from: 1) the first breakpoint in the oxygen uptake vs. carbon dioxide output curve (GET), 2) the [O2Hb]-T, and 3) a rating of 13 in perceived exertion (perceptual threshold: RPE13-T). Oxygen uptake at the different thresholds was not significantly different (P>0.05). Moreover, GET and [O2Hb]-T were significantly correlated: 1) to each other (r≥0.79; P≤0.001), and 2) to time-to-exhaustion (r=0.81 and r=0.72, respectively; Pexhaustion (P=0.148). The anaerobic threshold as identified from GET was concomitant to [O2Hb]-T. Both thresholds were correlated to time-to-exhaustion, and could therefore be used as a performance index in middle-duration events.

  9. Ergogenic effects of caffeine and sodium bicarbonate supplementation on intermittent exercise performance preceded by intense arm cranking exercise

    National Research Council Canada - National Science Library

    Marriott, Matthaus; Krustrup, Peter; Mohr, Magni

    2015-01-01

    Caffeine and sodium bicarbonate ingestion have been suggested to improve high-intensity intermittent exercise, but it is unclear if these ergogenic substances affect performance under provoked metabolic acidification...

  10. Different Intensities of Treadmill Running Exercise do Not Alter Melatonin Levels in Rats

    Directory of Open Access Journals (Sweden)

    Ionara Rodrigues Siqueira

    2011-04-01

    Full Text Available Background: Regular and moderate exercise has been considered an interesting neuroprotective strategy. Our research group demonstrated that a protocol of moderate exercise on a treadmill reduced, while a protocol of high-intensity exercise increased in vitro ischemic cell damage in Wistar rats. The molecular mechanisms by which physical exercise exerts neuroprotective effects remain unclear. Accumulating evidence suggests that exercise may have short- and long-term effects on melatonin secretion in humans. Melatonin, the main product of the pineal gland, has been shown to have neuroprotective effects in models of brain and spinal cord injury and cerebral ischemia. A dual modulation of melatonin secretion by physical activity has also been demonstrated. This study aimed to investigate the effect of different exercise intensities, moderate- and high-intensity exercise, on serum melatonin levels in rats. Methods: Thirty-five adult male Wistar rats were divided into non-exercised (sedentary and exercised (20- or 60-min sessions groups. The exercise protocols consisted of two weeks of daily treadmill training. Blood samples were collected approximately 16 hours after the last training session (8:00-10:00 and melatonin levels were assayed by ELISA. Results: The exercise protocols, two weeks of 20 min/day or 60 min/day of treadmill running, did not affect serum melatonin levels. Conclusion: Our data demonstrated that melatonin levels may not be directly involved in the exercise-induced, intensity-dependent dual effect on in vitro ischemia.

  11. Effects of plasma epinephrine on fat metabolism during exercise: interactions with exercise intensity.

    Science.gov (United States)

    Mora-Rodriguez, R; Coyle, E F

    2000-04-01

    This study determined the effects of elevated plasma epinephrine on fat metabolism during exercise. On four occasions, seven moderately trained subjects cycled at 25% of peak oxygen consumption (VO(2 peak)) for 60 min. After 15 min of exercise, subjects were intravenously infused with low (0.96 +/- 0.10 nM), moderate (1.92 +/- 0.24 nM), or high (3.44 +/- 0.50 nM) levels (all P < 0.05) of epinephrine to increase plasma epinephrine above control (Con; 0.59 +/- 0.10 nM). During the interval between 35 and 55 min of exercise, lipolysis [i.e., rate of appearance of glycerol] increased above Con (4.9 +/- 0.5 micromol. kg(-1). min(-1)) with low, moderate, and high (6.5 +/- 0.5, 7.1 +/- 0.8, and 10.6 +/- 1.2 micromol. kg(-1). min(-1), respectively; all P < 0.05) levels of epinephrine despite simultaneous increases in plasma insulin. The release of fatty acid into plasma also increased progressively with the graded epinephrine infusions. However, fatty acid oxidation was lower than Con (11.1 +/- 0.8 micromol. kg(-1). min(-1)) during moderate and high levels (8.7 +/- 0.7 and 8.1 +/- 0.9 micromol. kg(-1). min(-1), respectively; P < 0.05). In one additional trial, the same subjects exercised at 45% VO(2 peak) without epinephrine infusion, which produced a plasma epinephrine concentration identical to low levels. However, lipolysis was lower (i.e., 5.5 +/- 0.6 vs. 6.5 +/- 0.5 micromol. kg(-1). min(-1); P < 0.05). In conclusion, elevations in plasma epinephrine concentration during exercise at 25% of VO(2 peak) progressively increase whole body lipolysis but decrease fatty acid oxidation. Last, increasing exercise intensity from 25 to 45% VO(2 peak) attenuates the lipolytic actions of epinephrine.

  12. Comparison of cardioprotective benefits of vigorous versus moderate intensity aerobic exercise.

    Science.gov (United States)

    Swain, David P; Franklin, Barry A

    2006-01-01

    Aerobic fitness, not merely physical activity, is associated with a reduced risk of cardiovascular disease. Vigorous intensity exercise has been shown to increase aerobic fitness more effectively than moderate intensity exercise, suggesting that the former may confer greater cardioprotective benefits. An electronic search of published studies using PubMed was conducted for 2 types of investigations, epidemiologic studies that evaluated the benefits of physical activity of varying intensity levels and clinical trials that trained individuals at different intensities of exercise while controlling for the total energy expenditure. A secondary search was conducted using the references from these studies. The epidemiologic studies consistently found a greater reduction in risk of cardiovascular disease with vigorous (typically > or =6 METs) than with moderate intensity physical activity and reported more favorable risk profiles for individuals engaged in vigorous, as opposed to moderate, intensity physical activity. Clinical trials generally reported greater improvements after vigorous (typically > or =60% aerobic capacity) compared with moderate intensity exercise for diastolic blood pressure, glucose control, and aerobic capacity, but reported no intensity effect on improvements in systolic blood pressure, lipid profile, or body fat loss. In conclusion, if the total energy expenditure of exercise is held constant, exercise performed at a vigorous intensity appears to convey greater cardioprotective benefits than exercise of a moderate intensity.

  13. Influence of work-interval intensity and duration on time spent at a high percentage of VO2max during intermittent supramaximal exercise.

    Science.gov (United States)

    Wakefield, Benjamin R; Glaister, Mark

    2009-12-01

    The purpose of this study was to examine the effect of work-interval duration (WID) and intensity on the time spent at, or above, 95% VO2max (T95 VO2max) during intermittent bouts of supramaximal exercise. Over a 5-week period, 7 physically active men with a mean (+/-SD) age, height, body mass, and VO2max of 22 +/- 5 years, 181.5 +/- 5.6 cm, 86.4 +/- 11.4 kg, and 51.5 +/- 1.5 ml.kg-1.min-1, respectively, attended 7 testing sessions. After completing a submaximal incremental test on a treadmill to identify individual oxygen uptake/running velocity relationships, subjects completed a maximal incremental test to exhaustion to VO2max and subsequently (from the aforementioned relationship) the minimum velocity required to elicit VO2max (vVO2max). In a random order, subjects then carried out 3 intermittent runs to exhaustion at both 105% and 115% vVO2max. Each test used a different WID (20 s, 25 s, or 30 s) interspersed with 20-second passive recovery periods. Results revealed no significant difference in T95 vVO2max for intermittent runs at 105% versus 115% vVO2max (p = 0.142). There was, however, a significant effect (p VO2max, with WIDs of 30 seconds enabling more time relative to WIDs of 20 seconds (p = 0.018) and 25 seconds (p = 0.009). Moreover, there was an interaction between intensity and duration such that the effect of WID was magnified at the lower exercise intensity (p = 0.046). In conclusion, despite a number of limitations, the results of this investigation suggest that exercise intensities of approximately 105% vVO2max combined with WIDs greater than 25 seconds provide the best way of optimizing T95 VO2max when using fixed 20-second stationary rest periods.

  14. Intense and exhaustive exercise induce oxidative stress in skeletal muscle

    Directory of Open Access Journals (Sweden)

    T Thirumalai

    2011-03-01

    Full Text Available Objective: To assess the oxidative stress and antioxidant defense system in the skeletal muscle of male albino rats subjected to strenuous exercise programme. Methods: Wistar strain albino rats were subjected to exhaustive swimming exercise programme daily for a period of five days. The thiobarbituric acid reactive substances (TBARS, conjugated dienes, superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase were measured in the gastrocnemius muscle of the exercised animals. Results: The elevated levels of TBARS and conjugated dienes indicated the oxidative stress in the gastrocemius muscle of the exercised animals. The depleted activity levels of superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase in the exercise animals indicated the increased oxidative stress and decreased antioxidative defense system in the muscle. Conclusions: The study suggests that prolonged strenuous exercise programme can induce oxidative stress and therefore an optimal level of exercise schedule should be advocated to obtain the maximum benefit of exercise programme.

  15. The effect of high and low exercise intensity periods on a simple memory recognition test

    Directory of Open Access Journals (Sweden)

    Ben Rattray

    2016-09-01

    Conclusion: Changes in cognitive performance with variations in exercise intensity are likely to have implications for sport and occupational settings. The timing of cognitive tests to exercise intensity changes as well as use of short cognitive assessments will be important for future work.

  16. Moderating influence of dominant attentional style and exercise intensity on responses to asynchronous music.

    Science.gov (United States)

    Hutchinson, Jasmin C; Karageorghis, Costas I

    2013-12-01

    We examined independent and combined influences of asynchronous music and dominant attentional style (DAS) on psychological and psychophysical variables during exercise using mixed methods. Participants (N = 34) were grouped according to DAS and completed treadmill runs at three intensities (low, moderate, high) crossed with three music conditions (motivational, oudeterous, no-music control). State attentional focus shifted from dissociative to associative with increasing intensity and was most aligned with DAS during moderate-intensity exercise. Both music conditions facilitated dissociation at low-to-moderate intensities. At high exercise intensity, both music conditions were associated with reduced RPE among participants with an associative DAS. Dissociators reported higher RPE overall during moderate and high intensities. Psychological responses were most positive in the motivational condition, followed by oudeterous and control. Findings illustrate the relevance of individual differences in DAS as well as task intensity and duration when selecting music for exercise.

  17. Investigation of Intensity Levels during Video Classroom Exercise Sessions

    Science.gov (United States)

    Caldwell, Thad; Ratliffe, Tom

    2014-01-01

    Classroom Exercises for the Body and Brain was developed in the state of Georgia by the HealthMPowers organization to help classroom teachers provide structured physical activity for their elementary students in their classrooms. These brief video exercises were designed for students to participate at their desks as exercise breaks, as energy…

  18. Benefits of a low intensity exercise programme during haemodialysis sessions in elderly patients

    Directory of Open Access Journals (Sweden)

    Vicent Esteve Simo

    2015-07-01

    Conclusions: (1 An adapted low intensity exercise programme improved muscle strength, functional capacity and health-related quality of life in our elderly patients on HD. (2 Our results highlight the benefits from exercise in HD patients even in this elderly population. (3 In elderly patients on HD, it is worth considering an adapted low intensity intradialytic exercise programme as a part of a comprehensive care.

  19. Preferred intensity exercise for adolescents receiving treatment for depression: a pragmatic randomised controlled trial

    OpenAIRE

    Carter, Tim; Guo, Boliang; Turner, David; Morres, Ioannis; Khalil, Elizabeth; Brighton, Emily; Armstrong, Marie; Callaghan, Patrick

    2015-01-01

    Background: Exercise has been shown to be effective in treating depression, but trials testing the effect of exercise for depressed adolescents utilising mental health services are rare. The aim of this study was to determine the effectiveness of a preferred intensity exercise intervention on the depressive symptoms of adolescents with depression. Methods: We randomly assigned 87 adolescents who were receiving treatment for depression to either 12 sessions of aerobic exercise at preferred int...

  20. The effects of music preference and exercise intensity on psychological variables.

    Science.gov (United States)

    Dyrlund, Allison K; Wininger, Steven R

    2008-01-01

    The purpose of this study was to examine the effects of music preference and exercise intensity on exercise enjoyment, perceived exertion (RPE), and attentional focus. Participants were assigned to 1 of 3 music preference conditions (most preferred, least preferred, or no music) and walked/ran on a treadmill at 1 of 3 exercise intensities (low, moderate, or high) for 20 minutes. Measures of exercise enjoyment, RPE, and attentional focus (association, dissociation, distress) were taken. A 3 x 3 ANOVA on enjoyment revealed that when participants paid attention to the music, music accounted for roughly 5% of the variance in exercise enjoyment (p = .04). Results of a 3 (music) x 3 (intensity) repeated measures ANOVA on RPE showed a main effect of intensity (p music and no interaction effect. A 3 x 3 ANOVA on attentional focus revealed that those in the high intensity condition reported the greatest association (p music condition reported the highest levels of dissociation.

  1. Effects of high-intensity exercise on leptin and testosterone concentrations in well-trained males.

    Science.gov (United States)

    Kraemer, Robert R; Durand, Robert J; Acevedo, Edmund O; Johnson, Lisa G; Synovitz, Linda B; Kraemer, Ginger R; Gimpel, Terry; Castracane, V Daniel

    2003-08-01

    A number of investigations have examined the effect of exercise on leptin concentrations, because leptin is associated with obesity, satiety, and reproductive function. High-intensity exercise is known to increase testosterone, an inhibitor of leptin. The objective of the study was to determine whether the leptin responses to a progressive, intermittent exercise protocol were related to serum testosterone concentrations. Most previous studies have examined leptin responses to low or moderately high exercise intensities. A second objective was to determine whether leptin responses were different than previous experiments using intermittent moderate and high-intensity exercise. Well-trained runners completed strenuous intermittent exercise consisting of treadmill running at 60, 75, 90, and 100% VO(2 max) and a subsequent resting control trial was also conducted. There were significant increases in mean serum levels of leptin and testosterone with both quickly returning to baseline during recovery, but no relationship between the two hormones was found. After examining individual data for both hormones, it was discovered that subjects could be classified as leptin responders or nonresponders, whereas testosterone increased in all subjects. Responders had elevated serum leptin levels at baseline and exhibited increases after high-intensity exercise, whereas nonresponders did not show changes in leptin during exercise. Data suggest testosterone levels do not acutely affect leptin responses to exercise or 1-h of recovery. Moreover, varied leptin responses to intense exercise in comparable well-trained runners was observed and was associated with baseline leptin concentrations.

  2. The Effect of Vigorous- Versus Moderate-Intensity Aerobic Exercise on Insulin Action.

    Science.gov (United States)

    McGarrah, Robert W; Slentz, Cris A; Kraus, William E

    2016-12-01

    Due to the beneficial effects on a wide range of modern medical conditions, most professional societies recommend regular aerobic exercise as part of a healthy lifestyle. Many of the exercise-related health benefits exhibit a dose-response relationship: Up to a point, more exercise is more beneficial. However, recent studies have suggested that different exercise intensities may provide distinct health benefits, independent of energy expenditure (i.e., exercise dose). One of these benefits, primarily mediated by the skeletal muscle, is exercise-related changes in insulin action and glucose homeostasis. Glucose uptake in the exercising muscle occurs through insulin-independent mechanisms whose downstream signaling events ultimately converge with insulin-signaling pathways, a fact that may explain why exercise and insulin have additive effect on skeletal muscle glucose uptake. Although the existing evidence is somewhat conflicting, well-controlled randomized studies suggest that, when controlled for total energy expenditure, moderate-intensity aerobic exercise improves insulin sensitivity more than vigorous-intensity aerobic exercise. The mechanisms underlying this difference are largely unknown. One possible explanation involves enhanced metabolism of fatty acid stores in the skeletal muscle by moderate-intensity exercise, which may directly improve insulin sensitivity. Overall, new technologic and physiologic investigative tools are beginning to shed light on the biology. Further understanding of these mechanisms will lead to better understanding of the clinical implications of a healthy lifestyle and may ultimately offer new therapeutic targets for common medical conditions such as insulin resistance and diabetes.

  3. 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!

  4. Substrate metabolism during different exercise intensities in endurance-trained women.

    Science.gov (United States)

    Romijn, J A; Coyle, E F; Sidossis, L S; Rosenblatt, J; Wolfe, R R

    2000-05-01

    We have studied eight endurance-trained women at rest and during exercise at 25, 65, and 85% of maximal oxygen uptake. The rate of appearance (R(a)) of free fatty acids (FFA) was determined by infusion of [(2)H(2)]palmitate, and fat oxidation rates were determined by indirect calorimetry. Glucose kinetics were assessed with [6,6-(2)H(2)]glucose. Glucose R(a) increased in relation to exercise intensity. In contrast, whereas FFA R(a) was significantly increased to the same extent in low- and moderate-intensity exercise, during high-intensity exercise, FFA R(a) was reduced compared with the other exercise values. Carbohydrate oxidation increased progressively with exercise intensity, whereas the highest rate of fat oxidation was during exercise at 65% of maximal oxygen uptake. After correction for differences in lean body mass, there were no differences between these results and previously reported data in endurance-trained men studied under the same conditions, except for slight differences in glucose metabolism during low-intensity exercise (Romijn JA, Coyle EF, Sidossis LS, Gastaldelli A, Horowitz JF, Endert E, and Wolfe RR. Am J Physiol Endocrinol Metab 265: E380-E391, 1993). We conclude that the patterns of changes in substrate kinetics during moderate- and high-intensity exercise are similar in trained men and women.

  5. Electromyographic Activities of Trunk Muscles Due to Different Exercise Intensities during Pulley-based Shoulder Exercises on an Unstable Surface.

    Science.gov (United States)

    Cha, Jae Yun; Shin, Doo Chul; Shin, Seung Ho; Lee, Myung Mo; Lee, Kyoung Jin; Song, Chang Ho

    2014-05-01

    [Purpose] This study examined the relationship between core stability and exercise intensity during a pulley-based shoulder exercise (PBSE) on an unstable support surface. [Subjects] Twenty healthy college students enrolled in this study. [Methods] Surface EMG was carried out in twenty healthy adult men. The electromyographic activities of the rectus abdominis (RA), erector spinae (ES), exercises with 14 kg or 26 kg of resistance and external oblique (EO) muscles during pulley-based shoulder on an unstable support surface (USS) were compared. [Results] The EMG signals of the RA, ES, and EO did not increase with increasing exercise resistance. [Conclusion] Increasing the exercise intensity to increase the core stability during PBSE on a USS may be ineffective.

  6. 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.

  7. Determining the anaerobic threshold in postpolio syndrome: comparison with current guidelines for training intensity prescription

    NARCIS (Netherlands)

    Voorn, Eric L.; Gerrits, Karin H.; Koopman, Fieke S.; Nollet, Frans; Beelen, Anita

    2014-01-01

    To determine whether the anaerobic threshold (AT) can be identified in individuals with postpolio syndrome (PPS) using submaximal incremental exercise testing, and to compare current guidelines for intensity prescription in PPS with the AT. Cohort study. Research laboratory. Individuals with PPS

  8. Habitual exercise decreases systolic blood pressure during low-intensity resistance exercise in healthy middle-aged and older individuals.

    Science.gov (United States)

    Otsuki, Takeshi; Kotato, Takahiro; Zempo-Miyaki, Asako

    2016-10-01

    Since aerobic exercise (e.g., walking) and resistance exercise (e.g., lifting objects and mopping) are both parts of the activities of daily living, an exaggerated elevation in systolic blood pressure (SBP) during aerobic and resistance exercise is an early marker of cardiovascular disease. This study investigated the effects of habitual exercise on SBP during low-intensity resistance exercise using both cross-sectional and interventional approaches. First, in 57 normotensive women (61.9 ± 1.0 yr of age), daily physical activity level, as assessed by triaxial accelerometry, was correlated with SBP during resistance exercise at 20 and 40% of the 1 repetition maximum (r = -0.408 and r = -0.348, respectively). Maximal oxygen uptake was correlated with SBP during exercise at 20% (r = -0.385) and 40% (r = -0.457). Physical activity level or maximal oxygen uptake was identified as a predictor of SBP during the exercise in stepwise regression analysis, independent of SBP at rest and other factors (R(2) = 0.729-0.781). Second, 66 men and women (64.6 ± 0.9 yr of age) participated in a 6-wk intervention as a part of the training (walking, 4.3 ± 0.3 days/wk, 55.6 ± 4.1 min/day, 70.7 ± 1.2% of maximal heart rate) or control group. SBP during resistance exercise in the training group decreased after the intervention (before vs. after: 20%, 143 ± 4 vs. 128 ± 4 mmHg; and 40%, 148 ± 5 vs. 134 ± 4 mmHg). In the control group, there were no significant differences in SBP before and after the intervention. SBP during resistance exercise after the intervention was lower in the training group relative to the control group. These results suggest that habitual exercise decreases SBP during low-intensity resistance exercise. Copyright © 2016 the American Physiological Society.

  9. Kinesiophobia is associated with pain intensity but not pain sensitivity before and after exercise

    DEFF Research Database (Denmark)

    Vaegter, H. B.; Madsen, A. B.; Handberg, G.

    2018-01-01

    pre-post within-subject study. SETTING: An exercise laboratory in a multidisciplinary pain clinic. PARTICIPANTS: Fifty-four patients with chronic musculoskeletal pain. INTERVENTIONS: Acute aerobic and isometric leg exercises. MAIN OUTCOME MEASURES: Clinical pain intensity (numerical rating scale......, range 0 to 10), Tampa Scale of Kinesiophobia, aerobic and isometric exercise performances (intensity and maximal voluntary contraction), and PPTs at local and remote body areas before and after exercise conditions. RESULTS: Patients with a high degree of kinesiophobia demonstrated increased pain...... differences were found in PPTs before and after exercise. CONCLUSIONS: Clinical pain intensity was significantly higher in patients with a high degree of kinesiophobia compared with patients with a low degree of kinesiophobia. Despite a difference in isometric exercise performance, the hypoalgesic responses...

  10. 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.

  11. EFFECTS OF ACUTE PHYSICAL EXERCISE OF VARYING INTENSITY ON LIPID METABOLISM IN MIDDLE AGED MEN

    Directory of Open Access Journals (Sweden)

    G. E. Roytberg

    2010-01-01

    Full Text Available Aim. To investigate effects of acute physical exercise of varying intensity on lipid metabolism in middle aged men.Material and methods. Two bouts of physical exercise of moderate and high intensity were performed in 54 clinically healthy men aged 30-45 y.o. without obesity with subsequent assessment of lipid profile (total cholesterol, high density lipoprotein cholesterol, triglyceride levels, and atherogenic index. Effect of physical exercise on the lipid profile as studied both in the whole group and in subjects with and without insulin resistance.Results. Acute physical exercise of moderate and high intensity produced beneficial effects on lipid parameters (increase in cholesterol of high density lipoprotein level and reduction of atherogenic index. Increased intensity of physical exercise caused more prominent improvement of lipid profile in subjects without insulin resistance. However subjects with insulin resistance had weaker response to physical exercise than individuals without insulin resistance did and increased intensity of physical exercise did not cause significant improvement of lipid parameters in subjects with insulin resistance.Conclusion. Response to moderate or high intensive physical exercise may depend on baseline metabolic profile. It should be taken into account under development of preventive programs for modifying risk factors of cardio-vascular diseases and type 2 diabetes mellitus.

  12. Changes in satellite cells in human skeletal muscle after a single bout of high intensity exercise

    DEFF Research Database (Denmark)

    Crameri, Regina M; Langberg, Henning; Magnusson, Peter

    2004-01-01

    No studies to date have reported activation of satellite cells in vivo in human muscle after a single bout of high intensity exercise. In this investigation, eight individuals performed a single bout of high intensity exercise with one leg, the contralateral leg being the control. A significant...... increase in mononuclear cells staining for the neural cell adhesion molecule (N-CAM) and fetal antigen 1 (FA1) were observed within the exercised human vastus lateralis muscle on days 4 and 8 post exercise. In addition, a significant increase in the concentration of the FA1 protein was determined...

  13. Psychobiological Responses to Preferred and Prescribed Intensity Exercise in Major Depressive Disorder.

    Science.gov (United States)

    Meyer, Jacob D; Ellingson, Laura D; Koltyn, Kelli F; Stegner, Aaron J; Kim, Jee-Seon; Cook, Dane B

    2016-11-01

    Exercise acutely improves mood in major depressive disorder (MDD). However, it is unknown whether benefits differ depending on whether exercise intensity is self-selected or prescribed. This study aimed to compare psychological and biological responses to preferred and prescribed steady-state exercise intensities to a patient-selected preferred intensity. Female adults (N = 24, age = 38.6 ± 14.0 yr) diagnosed with MDD completed four 30-min sessions of cycling exercise at three prescribed intensities (RPE of 11, 13, and 15) and one session with a self-selected intensity (preferred). Order was randomized and counterbalanced. Depressed mood (DM) was evaluated before, 10 min, and 30 min postexercise using the Profile of Mood States. Serum brain-derived neurotrophic factor (BDNF) was measured before and within 10 min postexercise. Changes in BDNF and DM for the preferred session were compared with the following prescribed sessions: 1) performed at the most similar intensity (matched on RPE; closest) and 2) with the greatest improvement in DM (greatest). Compared with the preferred session, improvement in DM was significantly larger after the greatest session (30 min postexercise: -11.8 ± 7.4 vs -3.4 ± 4.8), and the BDNF response was significantly greater after the closest session (5.4 ± 6.9 vs -1.4 ± 9.8 ng·mL). Permitting patients to select their own exercise intensity did not maximize improvements in mood. Further, preferred intensity exercise was also associated with a smaller BDNF response. Overall, the results suggest that exercise undertaken to improve mood should be prescribed on an individual basis in MDD and not necessarily based on the patient's preferred intensity. Clinicians, psychologists, and other practitioners should consider providing clear exercise intensity recommendations for symptom management in depression rather than allowing patients to self-select their intensity.

  14. Effects of treadmill exercise intensity on spatial working memory and long-term memory in rats.

    Science.gov (United States)

    Wang, Xiao-Qin; Wang, Gong-Wu

    2016-03-15

    Moderate exercise promotes learning and memory. Most studies mainly focused on memory exercise effects of in the ageing and patients. There is lack of quantitative research about effect of regular exercise intensity on different memory types in normal subjects. Present study investigated the effects of different intensities of treadmill exercise on working memory and long-term memory. Fifty female Wistar rats were trained by T-maze delayed spatial alternation (DSA) task with 3 delays (10s, 60s and 300s). Then they got a 30min treadmill exercise for 30days in 4 intensities (control, 0m/min; lower, 15m/min; middle, 20m/min, and higher, 30m/min). Then animals were tested in DSA, passive avoidance and Morris water maze tasks. 1. Exercise increased the neuronal density of hippocampal subregions (CA1, CA3 and dentate gyrus) vs. naïve/control. 2. In DSA task, all groups have similar baseline, lower intensity improved 10s delay accuracy vs. baseline/control; middle and higher intensities improved 300s delay accuracy vs. baseline/control. 3. In water maze learning, all groups successfully found the platform, but middle intensity improved platform field crossing times vs. control in test phase. Present results suggested that treadmill exercise can improve long-term spatial memory and working memory; lower intensity benefits to short-term delayed working memory, and middle or higher intensity benefits to long-term delayed working memory. There was an inverted U dose-effect relationship between exercise intensity and memory performance, but exercise -working memory effect was impacted by delay duration. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Effect of acute nitrate ingestion on V̇O2response at different exercise intensity domains.

    Science.gov (United States)

    Ghiarone, Thaysa; Ataide-Silva, Thays; Bertuzzi, Romulo; McConell, Glenn Kevin; Lima-Silva, Adriano Eduardo

    2017-11-01

    While nitrate supplementation influences oxygen uptake (V̇O 2 ) response to exercise, this effect may be intensity dependent. The purpose of this study was to investigate the effect of acute nitrate supplementation on V̇O 2 response during different exercise intensity domains in humans. Eleven men ingested 10 mg·kg -1 body mass (8.76 ± 1.35 mmol) of sodium nitrate or sodium chloride (placebo) 2.5 h before cycling at moderate (90% of gas exchange threshold; GET), heavy (GET + 40% of the difference between GET and peak oxygen uptake (V̇O 2peak ), Δ 40) or severe (GET + 80% of the difference between GET and V̇O 2peak , Δ 80) exercise intensities. Volunteers performed exercise for 10 min (moderate), 15 min (heavy) or until exhaustion (severe). Acute nitrate supplementation had no effect on any V̇O 2 response parameters during moderate and severe exercise intensities. However, the V̇O 2 slow amplitude (nitrate: 0.93 ± 0.36 L·min -1 vs. placebo: 1.13 ± 0.59 L·min -1 , p = 0.04) and V̇O 2 slow gain (nitrate: 5.81 ± 2.37 mL·min -1 ·W -1 vs. placebo: 7.09 ± 3.67 mL·min -1 ·W -1 , p = 0.04) were significantly lower in nitrate than in placebo during the heavy exercise intensity. There was no effect of nitrate on plasma lactate during any exercise intensity (p > 0.05). Time to exhaustion during the severe exercise intensity was also not affected by nitrate (p > 0.05). In conclusion, acute nitrate supplementation reduced the slow component of V̇O 2 only when performing heavy-intensity exercise, which might indicate an intensity-dependent effect of nitrate on V̇O 2 response.

  16. Is Moderate Intensity Exercise Training Combined with High Intensity Interval Training More Effective at Improving Cardiorespiratory Fitness than Moderate Intensity Exercise Training Alone?

    Directory of Open Access Journals (Sweden)

    Brendon H. Roxburgh, Paul B. Nolan, Ryan M. Weatherwax, Lance C. Dalleck

    2014-09-01

    Full Text Available The purpose of this study was to compare the effectiveness of either continuous moderate intensity exercise training (CMIET alone vs. CMIET combined with a single weekly bout of high intensity interval training (HIIT on cardiorespiratory fitness. Twenty nine sedentary participants (36.3 ± 6.9 yrs at moderate risk of cardiovascular disease were recruited for 12 weeks of exercise training on a treadmill and cycle ergometer. Participants were randomised into three groups: CMIET + HIIT (n = 7; 8-12 x 60 sec at 100% VO2max, 150 sec active recovery, CMIET (n = 6; 30 min at 45-60% oxygen consumption reserve (VO2R and a sedentary control group (n = 7. Participants in the CMIET + HIIT group performed a single weekly bout of HIIT and four weekly sessions of CMIET, whilst the CMIET group performed five weekly CMIET sessions. Probabilistic magnitude-based inferences were determined to assess the likelihood that the true value of the effect represents substantial change. Relative VO2max increased by 10.1% (benefit possible relative to control in in the CMIET + HIIT group (32.7 ± 9.2 to 36.0 ± 11.5 mL·kg-1·min-1 and 3.9% (benefit possible relative to control in the CMIET group (33.2 ± 4.0 to 34.5 ± 6.1 mL·kg-1·min-1, whilst there was a 5.7% decrease in the control group (30.0 ± 4.6 to 28.3 ± 6.5 mL·kg-1·min-1. It was ‘unclear’ if a clinically significant difference existed between the effect of CMIET + HIIT and CMIET on the change in VO2max. Both exercising groups showed clinically meaningful improvements in VO2max. Nevertheless, it remains ‘unclear’ whether one type of exercise training regimen elicits a superior improvement in cardiorespiratory fitness relative to its counterpart.

  17. The Effect of Music on Exercise Intensity among Children with Autism Spectrum Disorder: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Ashley C. Woodman

    2018-02-01

    Full Text Available Children with autism spectrum disorder (ASD are at risk for obesity, commonly have sleep disorders, and exhibit stereotypic behaviors that disrupt their learning. Vigorous levels of exercise have been shown to ameliorate these issues in children with ASD, but little research exists to provide techniques for motivating children with ASD to engage in exercise. The present study examined the effect of music on exercise intensity in a group of 13 elementary school students with ASD. Data were collected across six days during structured (e.g., verbal and physical prompts and unstructured (e.g., minimal prompting exercise periods. During these exercise periods, three music conditions were randomized: no music, slow-tempo music, and fast-tempo music. Exercise intensity, measured in Metabolic Equivalent of Tasks by triaxial accelerometers, was greatest during the structured exercise periods and during the slow music condition. Student characteristics moderated the impact of music condition on exercise intensity, such that students with high levels of adaptive behavior or lower levels of maladaptive behavior displayed greater exercise intensity during the fast music condition.

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

    Directory of Open Access Journals (Sweden)

    Madhusudhan

    2015-06-01

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

  19. THE INFLUENCE ON SPEED ANTISTAX RESTORE FUNCTIONALITY ANIMALS AFTER INTENSE EXERCISE

    Directory of Open Access Journals (Sweden)

    A. V. Voronkov

    2013-01-01

    Full Text Available A promising approach for the correction of functional disorders associated with fatigue, is the use of an-tioxidant resources, particularly flavonoids. Therefore, the aim is to study the influence of Antistax a dose of 100 mg / kg per os on the performance and portability of intense exercise in rats. Intense exercise simulated swim-ming animals with a load equal to 5% of body weight for 7 days. Physical performance was evaluated on a long voyage. Application Antistax significantly increased the efficiency of the animals after intense exercise com-pared with the control groups and the intact animal

  20. High-intensity training reduces CD8+ T-cell redistribution in response to exercise

    NARCIS (Netherlands)

    Witard, O.C.; Turner, J.E.; Jackman, S.R.; Tipton, K.D.; Jeukendrup, A.E.; Kies, A.K.; Bosch, J.A.

    2012-01-01

    Purpose: We examined whether exercise-induced lymphocytosis and lymphocytopenia are impaired with high-intensity training. Methods: Eight trained cyclists (V·O2max = 64.2 ± 6.5 mL·kg-1·min-1) undertook 1 wk of normal-intensity training and a second week of high-intensity training. On day 7 of each

  1. 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

  2. Targeting specific interstitial glycemic parameters with high-intensity interval exercise and fasted-state exercise in type 2 diabetes.

    Science.gov (United States)

    Terada, Tasuku; Wilson, Ben J; Myette-Cόté, Etienne; Kuzik, Nicholas; Bell, Gordon J; McCargar, Linda J; Boulé, Normand G

    2016-05-01

    To compare the acute glycemic responses to a bout of high-intensity interval exercise (HIIE) and energy-matched moderate-intensity continuous exercise (MICE) performed under fasted and postprandial conditions. A randomized, controlled, crossover design was used. Ten individuals with type 2 diabetes were each tested in five experimental conditions after an overnight fast: 1) fasted-state HIIE (HIIEfast); 2) post-breakfast HIIE (HIIEfed); 3) fasted-state MICE (MICEfast); 4) post-breakfast MICE (MICEfed); and 5) no exercise (control). MICE was performed at workload corresponding to 55% of V.V̇O2peak, whereas HIIE was composed of repetitions of three minutes at workload corresponding to 40% followed by one minute at workload corresponding to 100% V.V̇̇O2peak. Interstitial glucose was monitored by continuous glucose monitoring over 24h under standardized diet and medication. Fasted-state exercise attenuated postprandial glycemic increments (pbreakfast exercise did. HIIE reduced nocturnal and fasting glycemia on the day following exercise more than MICE did (main effect: both pbreakfast exercise does. Performing HIIE under fasted condition may be most advantageous as it lowered most aspects of glycemia. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. PGC-1α and exercise intensity dependent adaptations in mouse skeletal muscle

    DEFF Research Database (Denmark)

    Brandt, Nina; Dethlefsen, Maja Munk; Bangsbo, Jens

    2017-01-01

    LC3I and LC3II protein in PGC-1α KO. In addition, exercise-induced mRNA responses of PGC-1α isoforms were intensity dependent. In conclusion, these findings indicate that exercise intensity affected autophagy markers differently in skeletal muscle and suggest that PGC-1α regulates both acute......The aim of the present study was to examine the role of PGC-1α in intensity dependent exercise and exercise training-induced metabolic adaptations in mouse skeletal muscle. Whole body PGC-1α knockout (KO) and littermate wildtype (WT) mice performed a single treadmill running bout at either low...... and exercise training-induced autophagy in skeletal muscle potentially in a PGC-1α isoform specific manner....

  4. Can high-intensity exercise be more pleasant?: attentional dissociation using music and video.

    Science.gov (United States)

    Jones, Leighton; Karageorghis, Costas I; Ekkekakis, Panteleimon

    2014-10-01

    Theories suggest that external stimuli (e.g., auditory and visual) may be rendered ineffective in modulating attention when exercise intensity is high. We examined the effects of music and parkland video footage on psychological measures during and after stationary cycling at two intensities: 10% of maximal capacity below ventilatory threshold and 5% above. Participants (N = 34) were exposed to four conditions at each intensity: music only, video only, music and video, and control. Analyses revealed main effects of condition and exercise intensity for affective valence and perceived activation (p music-only and music-and-video conditions led to the highest valence and enjoyment scores during and after exercise regardless of intensity. Findings indicate that attentional manipulations can exert a salient influence on affect and enjoyment even at intensities slightly above ventilatory threshold.

  5. Fatigue during high-intensity intermittent exercise: application to bodybuilding.

    Science.gov (United States)

    Lambert, Charles P; Flynn, Michael G

    2002-01-01

    Resistance exercise is an activity performed by individuals interested in competition, those who wish to improve muscle mass and strength for other sports, and for individuals interested in improving their strength and physical appearance. In this review we present information suggesting that phosphocreatine depletion, intramuscular acidosis and carbohydrate depletion are all potential causes of the fatigue during resistance exercise. In addition, recommendations are provided for nutritional interventions, which might delay muscle fatigue during this type of activity.

  6. Increased slow wave sleep and reduced stage 2 sleep in children depending on exercise intensity.

    Science.gov (United States)

    Dworak, Markus; Wiater, Alfred; Alfer, Dirk; Stephan, Egon; Hollmann, Wildor; Strüder, Heiko K

    2008-03-01

    There is controversy about the consequences of physical exercise on human sleeping behaviors. Evidence suggests that voluntary physical exercise affects brain structures and functions. However, there are inconsistent data regarding the effects of exercise on sleep architecture and sleep continuity, especially the amounts of slow wave sleep (SWS) and rapid eye movement (REM) sleep. The aim of the present study was to investigate the effects of moderate and high intense physical exercise on vigilance state and sleep patterns in school-aged children. Eleven healthy children (12.6+/-0.8 years old) were recruited for this polysomnographic study and underwent two exercise sessions. The two exercise sessions on a bicycle ergometer were performed 3-4h prior to bedtime, lasted 30min and varied in intensity. The moderate-intensity exercise was at 65-70% of maximal heart rate (HR(max)) while the high-intensity exercise was at 85-90% HR(max) to exhaustion. Polysomnographic and physiological measurements, including oximetry, were made on three nights in random order and separated by 1 week. Vigilance tests were carried out before and after the three sleep periods. Only high-intensity exercise resulted in a significantly elevated SWS proportion and less sleep in stage 2 as well as a higher sleep efficiency and shorter sleep onset latency. No significant effects on REM sleep were found. The results suggest that exercise intensity is responsible for the effects on stage 2 sleep and SWS in children and support the hypothesis of homeostatic sleep regulation.

  7. The influence of intense intermittent versus moderate continuous exercise on postprandial lipemia.

    Science.gov (United States)

    Ferreira, Aparecido Pimentel; Ferreira, Cristiane Batisti; Souza, Vinícius Carolino de; Córdova, Cláudio Olavo de Almeida; Silva, Glauber Castelo Branco; Nóbrega, Otávio de Toledo; França, Nancí Maria de

    2011-01-01

    Postprandial lipemia is characterized by an increased concentration of circulating lipids after fat intake and is an independent risk factor for cardiovascular disease. Exercise is known to reduce postprandial lipemia and its negative clinical outcomes. This study investigated the effect of intense intermittent versus moderate continuous exercise using the same energy expenditure in postprandial lipemia. Twenty healthy men (aged 21.5 ± 3.5 years) performed a random sequence of either rest or 500 Kcal tests separated by a minimum 48 h interval as follows: (a) no exercise (control), (b) intense intermittent exercise, or (c) moderate continuous exercise. Each test series was completed 30 min before ingestion of a high-fat meal (1 g fat/kg). Venous blood was collected before and at 1, 2, 3 and 4 hours after the high-fat meal. Postprandial lipemia was assessed using the area under the curve approach as well as a kinetic profile of mean lipid variables. Statistical significance was tested at the p<0.05 level. With both statistical approaches, intense intermittent and moderate continuous exercises were both effective in reducing postprandial triglycerides; however, only intense intermittent exercise reduced the levels of postprandial very low density lipoprotein. Intense intermittent and continuous exercise produced lower levels of insulinemia using the area under the curve analysis only. Intense intermittent or continuous exercise with an energy expenditure of 500 kcal completed 30 min before ingestion of high-fat meal reduced postprandial lipid levels to different levels in physically active men. Understanding these relevant differences will enable clinicians to provide the best exercise prescription for patients.

  8. The influence of intense intermittent versus moderate continuous exercise on postprandial lipemia

    Directory of Open Access Journals (Sweden)

    Aparecido Pimentel Ferreira

    2011-01-01

    Full Text Available INTRODUCTION: Postprandial lipemia is characterized by an increased concentration of circulating lipids after fat intake and is an independent risk factor for cardiovascular disease. Exercise is known to reduce postprandial lipemia and its negative clinical outcomes. OBJECTIVE: This study investigated the effect of intense intermittent versus moderate continuous exercise using the same energy expenditure in postprandial lipemia. MATERIALS AND METHODS: Twenty healthy men (aged 21.5 + 3.5 years performed a random sequence of either rest or 500 Kcal tests separated by a minimum 48 h interval as follows: (a no exercise (control, (b intense intermittent exercise, or (c moderate continuous exercise. Each test series was completed 30 min before ingestion of a high-fat meal (1 g fat/kg. Venous blood was collected before and at 1, 2, 3 and 4 hours after the high-fat meal. Postprandial lipemia was assessed using the area under the curve approach as well as a kinetic profile of mean lipid variables. Statistical significance was tested at the p<0.05 level. RESULTS: With both statistical approaches, intense intermittent and moderate continuous exercises were both effective in reducing postprandial triglycerides; however, only intense intermittent exercise reduced the levels of postprandial very low density lipoprotein. Intense intermittent and continuous exercise produced lower levels of insulinemia using the area under the curve analysis only. CONCLUSION: Intense intermittent or continuous exercise with an energy expenditure of 500 kcal completed 30 min before ingestion of high-fat meal reduced postprandial lipid levels to different levels in physically active men. Understanding these relevant differences will enable clinicians to provide the best exercise prescription for patients.

  9. Exercising for Life? Energy Metabolism, Body Composition, and Longevity in Mice Exercising at Different Intensities

    NARCIS (Netherlands)

    Vaanholt, Lobke M.; Daan, Serge; Garland, Theodore; Visser, G. Henk; Garland Jr., Theodore

    2010-01-01

    Studies that have found a positive influence of moderate, non-exhaustive exercise on life expectancy contradict the rate-of-living theory, which predicts that high energy expenditure in exercising animals should shorten life. We investigated effects of exercise on energy metabolism and life span in

  10. 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.

  11. Virtual and live social facilitation while exergaming: competitiveness moderates exercise intensity.

    Science.gov (United States)

    Snyder, Amanda L; Anderson-Hanley, Cay; Arciero, Paul J

    2012-04-01

    Grounded in social facilitation theory, this study compared the impact on exercise intensity of a virtual versus a live competitor, when riding a virtual reality-enhanced stationary bike ("cybercycle"). It was hypothesized that competitiveness would moderate effects. Twenty-three female college students were exposed to three conditions on a cybercycle: solo training, virtual competitor, and live competitor. After training without a competitor (solo condition for familiarization with equipment), participants competed against a virtual avatar or live rider (random order of presentation). A repeated-measures analysis revealed a significant condition (virtual/live) by competitiveness (high/low) interaction for exercise intensity (watts). More competitive participants exhibited significantly greater exercise intensity when competing against a live versus virtual competitor. The implication is that live competitors can have an added social facilitation effect and influence exercise intensity, although competitiveness moderates this effect.

  12. Effect of high-intensity interval exercise on basal triglyceride metabolism in non-obese men

    National Research Council Canada - National Science Library

    Bellou, Elena; Magkos, Faidon; Kouka, Tonia; Bouchalaki, Eirini; Sklaveniti, Dimitra; Maraki, Maria; Tsekouras, Yiannis E; Panagiotakos, Demosthenes B; Kavouras, Stavros A; Sidossis, Labros S

    2013-01-01

    ..., but whether this applies to very low density lipoprotein (VLDL) metabolism is not known. We sought to examine the effect of a single bout of high-intensity interval aerobic exercise on basal VLDL-triglyceride (TG...

  13. Effect of muscle acidity on muscle metabolism and fatigue during intense exercise in man

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Madsen, K.; Kiens, Bente

    1996-01-01

    1. The aim of this study was to examine the effect of muscle pH on muscle metabolism and development of fatigue during intense exercise. 2. Seven subjects performed intense exhaustive leg exercise on two occasions: with and without preceding intense intermittent arm exercise leading to high...... (kg wet weight)-1 min-1). The rate of muscle glycogen breakdown was the same in C and HL (8.1 +/- 1.2 vs. 8.2 +/- 1.0 mmol (kg wet weight)-1 min-1). 5. The present data suggest that elevated muscle acidity does not reduce muscle glycogenolysis/glycolysis and is not the only cause of fatigue during...... intense exercise in man. Instead, accumulation of potassium in muscle interstitium may be an important factor in the development of fatigue....

  14. Benefits of Moderate-Intensity Exercise during a Calorie-Restricted Low-Fat Diet

    Science.gov (United States)

    Apekey, Tanefa A.; Morris, A. E. J.; Fagbemi, S.; Griffiths, G. J.

    2012-01-01

    Objective: Despite the health benefits, many people do not undertake regular exercise. This study investigated the effects of moderate-intensity exercise on cardiorespiratory fitness (lung age, blood pressure and maximal aerobic power, VO[subscript 2]max), serum lipids concentration and body mass index (BMI) in sedentary overweight/obese adults…

  15. Low blood flow at onset of moderate intensity exercise does not limit muscle oxygen uptake

    DEFF Research Database (Denmark)

    Nyberg, Michael Permin; Mortensen, Stefan Peter; Saltin, Bengt

    2010-01-01

    The effect of low blood flow at onset of moderate intensity exercise on the rate of rise in muscle oxygen uptake was examined. Seven male subjects performed a 3.5 minute one-legged knee-extensor exercise bout (24+/-1 (+/-S.D.) W) without (CON) and with (double blockade; DB) arterial infusion...

  16. Effects of music and video on perceived exertion during high-intensity exercise

    Directory of Open Access Journals (Sweden)

    Enoch C. Chow

    2017-03-01

    Conclusion: Music and video in combination may result in lower perceived exertion during high-intensity exercise when compared to music or video in isolation. Future research will be necessary to test if reductions in perceived exertion in response to dissociative attentional stimuli have implications for exercise adherence.

  17. Exercise training modalities in chronic heart failure: does high intensity aerobic interval training make the difference?

    Science.gov (United States)

    Giallauria, Francesco; Smart, Neil Andrew; Cittadini, Antonio; Vigorito, Carlo

    2016-10-14

    Exercise training (ET) is strongly recommended in patients with chronic heart failure (CHF). Moderate-intensity aerobic continuous ET is the best established training modality in CHF patients. In the last decade, however, high-intensity interval exercise training (HIIT) has aroused considerable interest in cardiac rehabilitation community. Basically, HIIT consists of repeated bouts of high-intensity exercise alternated with recovery periods. In CHF patients, HIIT exerts larger improvements in exercise capacity compared to moderate-continuous ET. These results are intriguing, mostly considering that better functional capacity translates into an improvement of symptoms and quality of life. Notably, HIIT did not reveal major safety issues; although CHF patients should be clinically stable, have had recent exposure to at least regular moderate-intensity exercise, and appropriate supervision and monitoring during and after the exercise session are mandatory. The impact of HIIT on cardiac dimensions and function and on endothelial function remains uncertain. HIIT should not replace other training modalities in heart failure but should rather complement them. Combining and tailoring different ET modalities according to each patient's baseline clinical characteristics (i.e. exercise capacity, personal needs, preferences and goals) seem the most astute approach to exercise prescription.

  18. Emotional Responsiveness after Low- and Moderate-Intensity Exercise and Seated Rest.

    Science.gov (United States)

    Smith, J. Carson; O'Connor, Patrick J.; Crabbe, James B.; Dishman, Rod K.

    2002-01-01

    Examined whether anxiety-reducing conditions of low- and moderate-intensity cycling exercise would lead to changes in emotional responsiveness to pictures designed to elicit pleasant neutral, and unpleasant emotions among healthy female college students. Results indicated that cycling exercise resulted in decreased baseline activity of facial…

  19. Moderate-to-High Intensity Physical Exercise in Patients with Alzheimer's Disease

    DEFF Research Database (Denmark)

    Hoffmann, Kristine; Sobol, Nanna A; Frederiksen, Kristian S

    2015-01-01

    BACKGROUND: Studies of physical exercise in patients with Alzheimer's disease (AD) are few and results have been inconsistent. OBJECTIVE: To assess the effects of a moderate-to-high intensity aerobic exercise program in patients with mild AD. METHODS: In a randomized controlled trial, we recruited...

  20. Impact of handgrip exercise intensity on brachial artery flow-mediated dilation.

    NARCIS (Netherlands)

    Atkinson, C.L.; Carter, H.H.; Dawson, E.A.; Naylor, L.H.; Thijssen, D.H.J.; Green, D.J.

    2015-01-01

    PURPOSE: Previous studies that have examined the impact of exercise intensity on conduit artery endothelial function have involved large muscle group exercise which induces local and systemic effects. The aim of this study was to examine flow-mediated dilation (FMD) before and after incremental

  1. Arterialized and venous blood lactate concentration difference during different exercise intensities

    Directory of Open Access Journals (Sweden)

    Leandro C. Felippe

    2017-06-01

    Conclusion: These results suggest a delayed lactate appearance in the venous blood, which is accentuated at higher exercise intensities. The lactate measured in arterialized and venous blood is interchangeable only when blood samples are collected at least 10 minutes after the exercise starts.

  2. High- and moderate-intensity aerobic exercise and excess post-exercise oxygen consumption in men with metabolic syndrome.

    Science.gov (United States)

    Larsen, I; Welde, B; Martins, C; Tjønna, A E

    2014-06-01

    Physical activity is central in prevention and treatment of metabolic syndrome. High-intensity aerobic exercise can induce larger energy expenditure per unit of time compared with moderate-intensity exercise. Furthermore, it may induce larger energy expenditure at post-exercise recovery. The aim of this study is to compare the excess post-exercise oxygen consumption (EPOC) in three different aerobic exercise sessions in men with metabolic syndrome. Seven men (age: 56.7 ± 10.8) with metabolic syndrome participated in this crossover study. The sessions consisted of one aerobic interval (1-AIT), four aerobic intervals (4-AIT), and 47-min continuous moderate exercise (CME) on separate days, with at least 48 h between each test day. Resting metabolic rate (RMR) was measured pre-exercise and used as baseline value. EPOC was measured until baseline metabolic rate was re-established. An increase in O2 uptake lasting for 70.4 ± 24.8 min (4-AIT), 35.9 ± 17.3 min (1-AIT), and 45.6 ± 17.3 min (CME) was observed. EPOC were 2.9 ± 1.7 L O2 (4-AIT), 1.3 ±  .1 L O2 (1-AIT), and 1.4 ± 1.1 L O2 (CME). There were significant differences (P EPOC was highest after 4-AIT. These data suggest that exercise intensity has a significant positive effect on EPOC in men with metabolic syndrome. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. 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

  4. Cardiorespiratory response to aerobic exercise programs with different intensity: 20 weeks longitudinal study.

    Science.gov (United States)

    Hulke, Sandip Meghnad; Phatak, Mrunal S; Vaidya, Yuganti P

    2012-07-01

    participation in regular intensive exercise is associated with a modest increase in left ventricular wall thickness and cavity size. The magnitude of improvement depends on frequency, intensity, type, and duration of exercise program. to determine the effect of sports training on LV morphology and function, lung function, and to know the intensity of the exercise program enough for these changes. this was a longitudinal study (20 weeks duration) done on the medical college students. three groups, doing exercise at different intensities, high intensity group (HG) [74.9±3.9 %HRmax], low intensity group (LG) [59.46±4.1%HRmax] and no exercise group (NG) were made, and their assessments were done using the echocardiography and pulmonary function test three times, first before start of the exercise program, second at the end of 10th week, and then at the end of the 20th week. 3 × 3 Anova test and Bonferroni's post-test using Graph pad prism5 software. significant improvement was seen in HG in majority of cardio respiratory parameters (VO2max, heart rate, LVIDD, LVIDS, EDV, MVV, PEFR, FVC) as compared to the LG (VO2max, heart rate, MVV, PEFR) and this improvement was specially seen at the end of the twentieth week. twenty weeks of training is helpful in improving aerobic power, MVV, and PEFR even the exercise is of moderate (LG) to high intensity (HG) but for overall cardio respiratory development physical training must be associated with very hard intensity if duration of the exercise program is short.

  5. Cardiorespiratory response to aerobic exercise programs with different intensity: 20 weeks longitudinal study

    Directory of Open Access Journals (Sweden)

    Sandip Meghnad Hulke

    2012-01-01

    Full Text Available Context: participation in regular intensive exercise is associated with a modest increase in left ventricular wall thickness and cavity size. The magnitude of improvement depends on frequency, intensity, type, and duration of exercise program. Aims: to determine the effect of sports training on LV morphology and function, lung function, and to know the intensity of the exercise program enough for these changes. Settings and design: this was a longitudinal study (20 weeks duration done on the medical college students. Material and methods: three groups, doing exercise at different intensities, high intensity group (HG [74.9±3.9 %HRmax], low intensity group (LG [59.46±4.1%HRmax] and no exercise group (NG were made, and their assessments were done using the echocardiography and pulmonary function test three times, first before start of the exercise program, second at the end of 10th week, and then at the end of the 20th week. Statistical analysis used: 3 × 3 Anova test and Bonferroni′s post-test using Graph pad prism5 software. Results: significant improvement was seen in HG in majority of cardio respiratory parameters (VO2max, heart rate, LVIDD, LVIDS, EDV, MVV, PEFR, FVC as compared to the LG (VO2max, heart rate, MVV, PEFR and this improvement was specially seen at the end of the twentieth week. Conclusions: twenty weeks of training is helpful in improving aerobic power, MVV, and PEFR even the exercise is of moderate (LG to high intensity (HG but for overall cardio respiratory development physical training must be associated with very hard intensity if duration of the exercise program is short.

  6. 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-.

  7. No Effect of Exercise Intensity on Appetite in Highly-Trained Endurance Women

    Directory of Open Access Journals (Sweden)

    Stephanie M. Howe

    2016-04-01

    Full Text Available In endurance-trained men, an acute bout of exercise is shown to suppress post-exercise appetite, yet limited research has examined this response in women. The purpose of this study was to investigate the effect of exercise intensity on appetite and gut hormone responses in endurance-trained women. Highly-trained women (n = 15, 18–40 years, 58.4 ± 6.4 kg, VO2MAX = 55.2 ± 4.3 mL/kg/min completed isocaloric bouts (500 kcals or 2093 kJ of moderate-intensity (MIE, 60% VO2MAX and high-intensity (HIE, 85% VO2MAX treadmill running at the same time of day, following a similar 48-h diet/exercise period, and at least 1-week apart. Blood was drawn pre-exercise (baseline, immediately post-exercise and every 20-min for the next 60-min. Plasma concentrations of acylated ghrelin, PYY3–36, GLP-1 and subjective appetite ratings via visual analog scale (VAS were assessed at each time point. Acylated ghrelin decreased (p = 0.014 and PYY3–36 and GLP-1 increased (p = 0.036, p < 0.0001 immediately post-exercise, indicating appetite suppression. VAS ratings of hunger and desire to eat decreased immediately post-exercise (p = 0.0012, p = 0.0031, respectively, also indicating appetite suppression. There were no differences between exercise intensities for appetite hormones or VAS. Similar to males, post-exercise appetite regulatory hormones were altered toward suppression in highly-trained women and independent of energy cost of exercise. Results are important for female athletes striving to optimize nutrition for endurance performance.

  8. Ammonia metabolism during intense dynamic exercise and recovery in humans

    DEFF Research Database (Denmark)

    Graham, T; Bangsbo, Jens; Gollnick, PD

    1990-01-01

     declined immediately on cessation of exercise. Recovery was complete in approximately 20 min. Arterial [NH3] increased less rapidly and reached itsmaximum 2-3 min into recovery. These data demonstrate that NH3 clearance is more sensitive to the cessation of exercise than is NH3 release from skeletal muscle. Muscle [NH......3] increased three to fourfold during exercise and represented 74 +/- 8% of the total net NH3 formation. Thus the change in muscle [NH3] alone underestimates the NH3 production. There was no evidence that the muscle-to-venous blood NH3 ratio shifts in accordance with the H+ data. Thus other factors...

  9. Effects of Exercise Intensity on Spatial Memory Performance and Hippocampal Synaptic Plasticity in Transient Brain Ischemic Rats

    OpenAIRE

    Pei-Cheng Shih; Yea-Ru Yang; Ray-Yau Wang

    2013-01-01

    Memory impairment is commonly noted in stroke survivors, and can lead to delay of functional recovery. Exercise has been proved to improve memory in adult healthy subjects. Such beneficial effects are often suggested to relate to hippocampal synaptic plasticity, which is important for memory processing. Previous evidence showed that in normal rats, low intensity exercise can improve synaptic plasticity better than high intensity exercise. However, the effects of exercise intensities on hippoc...

  10. High Intensity Exercise in Multiple Sclerosis: Effects on Muscle Contractile Characteristics and Exercise Capacity, a Randomised Controlled Trial.

    Directory of Open Access Journals (Sweden)

    Inez Wens

    Full Text Available Low-to-moderate intensity exercise improves muscle contractile properties and endurance capacity in multiple sclerosis (MS. The impact of high intensity exercise remains unknown.Thirty-four MS patients were randomized into a sedentary control group (SED, n = 11 and 2 exercise groups that performed 12 weeks of a high intensity interval (HITR, n = 12 or high intensity continuous cardiovascular training (HCTR, n = 11, both in combination with resistance training. M.vastus lateralis fiber cross sectional area (CSA and proportion, knee-flexor/extensor strength, body composition, maximal endurance capacity and self-reported physical activity levels were assessed before and after 12 weeks.Compared to SED, 12 weeks of high intensity exercise increased mean fiber CSA (HITR: +21 ± 7%, HCTR: +23 ± 5%. Furthermore, fiber type I CSA increased in HCTR (+29 ± 6%, whereas type II (+23 ± 7% and IIa (+23 ± 6%, CSA increased in HITR. Muscle strength improved in HITR and HCTR (between +13 ± 7% and +45 ± 20% and body fat percentage tended to decrease (HITR: -3.9 ± 2.0% and HCTR: -2.5 ± 1.2%. Furthermore, endurance capacity (Wmax +21 ± 4%, time to exhaustion +24 ± 5%, VO2max +17 ± 5% and lean tissue mass (+1.4 ± 0.5% only increased in HITR. Finally self-reported physical activity levels increased 73 ± 19% and 86 ± 27% in HCTR and HITR, respectively.High intensity cardiovascular exercise combined with resistance training was safe, well tolerated and improved muscle contractile characteristics and endurance capacity in MS.ClinicalTrials.gov NCT01845896.

  11. Moderate and Vigorous Intensity Exercise During Pregnancy and Gestational Weight Gain in Women with Gestational Diabetes.

    Science.gov (United States)

    Ehrlich, Samantha F; Sternfeld, Barbara; Krefman, Amy E; Hedderson, Monique M; Brown, Susan D; Mevi, Ashley; Chasan-Taber, Lisa; Quesenberry, Charles P; Ferrara, Assiamira

    2016-06-01

    Objectives To estimate the associations of moderate and vigorous intensity exercise during pregnancy with the rate of gestational weight gain (GWG) from gestational diabetes (GDM) diagnosis to delivery, overall and stratified by prepregnancy overweight/obesity. Methods Prospective cohort study with physical activity reported shortly after the GDM diagnosis and prepregnancy weight and post-diagnosis GWG obtained from electronic health records (n = 1055). Multinomial logistic regression models in the full cohort and stratified by prepregnancy overweight/obesity estimated associations of moderate and vigorous intensity exercise with GWG below and above the Institute of Medicine's (IOM) prepregnancy BMI-specific recommended ranges for weekly rate of GWG in the second and third trimesters. Results In the full cohort, any participation in vigorous intensity exercise was associated with decreased odds of GWG above recommended ranges as compared to no participation [odds ratio (95 % confidence interval): 0.63 (0.40, 0.99)], with a significant trend for decreasing odds of excess GWG with increasing level of vigorous intensity exercise. Upon stratification by prepregnancy overweight/obesity, significant associations were only observed for BMI ≥ 25.0 kg/m(2): any vigorous intensity exercise, as compared to none, was associated with 54 % decreased odds of excess GWG [0.46 (0.27, 0.79)] and significant trends were detected for decreasing odds of GWG both below and above the IOM's recommended ranges with increasing level of vigorous exercise (both P ≤ 0.03). No associations were observed for moderate intensity exercise. Conclusions for Practice In women with GDM, particularly overweight and obese women, vigorous intensity exercise during pregnancy may reduce the odds of excess GWG.

  12. 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

    exercise. An electrogoniometer synchronized to the EMG was used to determine whether peak EMG activity occurred during muscle-tendon unit lengthening, shortening, or no change in length. Mean EMG values were compared between the two recording sites for each exercise using the Student's t-test.Results: The lunge, dead lift, and kettle swings were low intensity (<50% MVIC and all showed higher EMG activity for semitendinosus than for biceps femoris. Bridge was low but approaching medium intensity, and the TRX, hamstring bridge, and hamstring curl were all medium intensity exercises (≥50% or <80% MVIC. The Nordic, fitball, and slide leg exercises were all high intensity exercises. Only the fitball exercise showed higher EMG activity in the biceps femoris compared with the semitendinosus. Only lunge and kettle swings showed peak EMG in the muscle-tendon unit lengthening phase and both these exercises involved faster speed.Conclusion: Some exercises selectively activated the lateral and medial distal hamstrings. Low, medium, and high intensity exercises were demonstrated. This information enables the clinician, strength and conditioning coach and physiotherapist to better understand intensity- and muscle-specific activation during hamstring muscle rehabilitation. Therefore, these results may help in designing progressive strengthening and rehabilitation and prevention programs.Keywords: hamstring injuries, exercise, rehabilitation

  13. The acute effect of moderate intensity aquatic exercise on coagulation factors in haemophiliacs.

    Science.gov (United States)

    Beltrame, Luis Gustavo Normanton; Abreu, Laurinda; Almeida, Jussara; Boullosa, Daniel Alexandre

    2015-05-01

    The objective of this cross-sectional study was to analyse the acute effect of aquatic exercise on haemostasis in persons with haemophilia. Ten adult haemophiliacs (8 type A, 2 type B) familiarized with aquatic training performed a 20-min exercise session in a swimming pool at an intensity of ~70% maximum heart rate (HR). Blood samples were collected immediately after the training session. The haemostatic parameters selected for analyses were factor VIII (FVIII), prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen. There were unclear effects of the exercise bout on FVIII and APTT, with a possibly beneficial effect on PT (-11·4%; 90% confidence interval: -26·1;3·3%), and a trivial change on fibrinogen levels. It was found an association between the mean rise in HR during exercise and the decrement in PT after exercise (r = 0·729; P = 0·026). The greater changes were observed in the patients diagnosed with a moderate level of haemophilia. It is concluded that a short bout of moderate intensity of aquatic exercise may have a positive influence on PT in adults with haemophilia with greater changes in those individuals exhibiting a greater rise in HR during exercise. This may be an important issue to the haemostatic control of haemophiliacs in clinical settings. Further studies are warranted for testing the influence of different aquatic exercise intensities on haemostasis. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  14. The Effects of Maximal Intensity Exercise on Cognitive Performance in Children

    Directory of Open Access Journals (Sweden)

    Samuel Roy David

    2017-06-01

    Full Text Available High intensity physical exercise has previously been found to lead to a decline in cognitive performance of adults. The aim of this study was to determine the effects of maximal intensity exercise on cognitive performance of children. Using a repeated-measures design, 20 children and adolescents aged 8-17 years completed a battery of tests measuring memory and attention. Forward and Backward Digit Span tests, the Rey Auditory-Verbal Learning Test (RAVLT and the Digit Symbol Substitution Test (DSST were performed at baseline, immediately after, and one hour after a maximal cardiopulmonary exercise test. Forward and Backward Digit Span scores significantly improved post-recovery compared with baseline measurements. There was a significant decrease in RAVLT scores post-exercise, which returned to baseline values after recovery. The DSST test scores were mildly elevated from post-exercise to after recovery. Maximal intensity exercise in children and adolescents may result in both beneficial and detrimental cognitive effects, including transient impairment in verbal learning. Cognitive functions applying short term memory improve following a recovery period. Parents, educators and coaches should consider these changes in memory and attention following high-intensity exercise activities in children.

  15. Determination of the exercise intensity that elicits maximal fat oxidation in individuals with obesity

    DEFF Research Database (Denmark)

    Jørgensen, Sune Dandanell; Præst, Charlotte Boslev; Søndergård, Stine Dam

    2017-01-01

    2max with the graded and the SCE protocol, respectively. In conclusion, there was a high-excellent correlation and a low CV between the two protocols, suggesting that the graded exercise protocol has a high inter-method reliability. However, considerable intra-individual variation and a trend......Maximal fat oxidation (MFO) and the exercise intensity that elicits MFO (FatMax) are commonly determined by indirect calorimetry during graded exercise tests in both obese and normal weight individuals. However, no protocol has been validated in individuals with obesity. Thus, the aims were...... to develop a graded exercise protocol for determination of FatMax in individuals with obesity, and to test validity and inter-method reliability. Fat oxidation was assessed over a range of exercise intensities in 16 individuals (Age: 28 (26-29) years, BMI: 36 (35-38) kg m-2) (95%CI) on a cycle ergometer...

  16. Moderate-intensity aerobic exercise improves sleep quality in men older adults

    Directory of Open Access Journals (Sweden)

    Shams Amir

    2013-01-01

    Full Text Available The purpose of present research was to investigate the effect of low and moderate intensity aerobic exercises on sleep quality in older adults. The statistical sample included 45 volunteer elderly men with age range of 60-70 years old that divided randomly in two experimental groups (aerobic exercise with low and moderate intensity and one control group. The maximum heart rate (MaxHR of subjects was obtained by subtracting one's age from 220. Furthermore, based on aerobic exercise type (40-50% MaxHR for low intensity group and 60-70% MaxHR for moderate intensity group the target MaxHR was calculated for each subject. The exercise protocol consisted of 8 weeks aerobic exercises (2 sessions in per-week based on Rockport one-mile walking/running test and the control group continued their daily activities. All subjects in per-test and post-test stages were completed the Petersburg Sleep Quality Index (PSQI. Results in post-test stage showed that there were significant differences between control and experimental groups in sleep quality and its components (P<0.05. Also, the Tukey Post Hoc showed that the moderate intensity group scores in sleep quality and its components were better than other groups (P<0.05. Finally, the low intensity group scores were better than control group (P<0.05. Generally, the present research showed that the aerobic exercises with moderate intensity have a positive and significant effect on sleep quality and its components. Thus, based on these findings, the moderate intensity aerobic exercises as a useful and medical method for improve the sleep quality among community older adults was recommended.

  17. Impact of Mild versus Moderate Intensity Aerobic Walking Exercise ...

    African Journals Online (AJOL)

    2014-03-01

    Mar 1, 2014 ... Material and Methods: Fifty male patients with moderate hemophilia, and age range from 25 to 45 years. The subjects were randomly ... Key Words: Aerobic exercise, bone metabolism, hand grip strength, hemophilia. African Health Sciences .... women results in alterations in biomarkers of bone remodeling ...

  18. The effect of high intensity interval exercise on postprandial triacylglycerol and leukocyte activation--monitored for 48 h post exercise.

    Directory of Open Access Journals (Sweden)

    Brendan Morris Gabriel

    Full Text Available Postprandial phenomenon are thought to contribute to atherogenesis alongside activation of the immune system. A single bout of high intensity interval exercise attenuates postprandial triacylglycerol (TG, although the longevity and mechanisms underlying this observation are unknown. The aims of this study were to determine whether this attenuation in postprandial TG remained 2 days after high intensity interval exercise, to monitor markers of leukocyte activation and investigate the underlying mechanisms. Eight young men each completed two three day trials. On day 1: subjects rested (Control or performed 5 x 30 s maximal sprints (high intensity interval exercise. On day 2 and 3 subjects consumed high fat meals for breakfast and 3 h later for lunch. Blood samples were taken at various times and analysed for TG, glucose and TG-rich lipoprotein (TRL-bound LPL-dependent TRL-TG hydrolysis (LTTH. Flow cytometry was used to evaluate granulocyte, monocyte and lymphocyte CD11b and CD36 expression. On day 2 after high intensity interval exercise TG area under the curve was lower (P<0.05 (7.46 ± 1.53 mmol/l/7h compared to the control trial (9.47 ± 3 .04 mmol/l/7h with no differences during day 3 of the trial. LTTH activity was higher (P<0.05 after high intensity interval exercise, at 2 hours of day 2, compared to control. Granulocyte, monocyte and lymphocyte CD11b expression increased with time over day 2 and 3 of the study (P<0.0001. Lymphocyte and monocyte CD36 expression decreased with time over day 2 and 3 (P<0.05. There were no differences between trials in CD11b and CD36 expression on any leukocytes. A single session of high intensity interval exercise attenuated postprandial TG on day 2 of the study, with this effect abolished by day 3.The reduction in postprandial TG was associated with an increase in LTTH. High intensity interval exercise had no effect on postprandial responses of CD11b or CD36.

  19. Enhancing energy expenditure and enjoyment of exercise during pregnancy through the addition of brief higher intensity intervals to traditional continuous moderate intensity cycling

    OpenAIRE

    Ong, Ming Jing; Wallman, Karen E.; Fournier, Paul A.; Newnham, John P.; Guelfi, Kym J.

    2016-01-01

    Background Current guidelines recommend that pregnant women without contraindications should engage in 30?min or more of moderate intensity exercise on most days of the week, however, many women fail to achieve this goal. This study examined the effect of adding brief higher intensity intervals to traditional continuous moderate intensity exercise on energy expenditure and the enjoyment of exercise in late pregnancy. This is important to determine given that any additional energy expenditure ...

  20. Losartan prevents heart fibrosis induced by long-term intensive exercise in an animal model.

    Directory of Open Access Journals (Sweden)

    Gemma Gay-Jordi

    Full Text Available RATIONALE: Recently it has been shown that long-term intensive exercise practice is able to induce myocardial fibrosis in an animal model. Angiotensin II is a profibrotic hormone that could be involved in the cardiac remodeling resulting from endurance exercise. OBJECTIVE: This study examined the antifibrotic effect of losartan, an angiotensin II type 1 receptor antagonist, in an animal model of heart fibrosis induced by long-term intense exercise. METHODS AND RESULTS: Male Wistar rats were randomly distributed into 4 experimental groups: Exercise, Exercise plus losartan, Sedentary and Sedentary plus losartan. Exercise groups were conditioned to run vigorously for 16 weeks. Losartan was orally administered daily before each training session (50 mg/kg/day. Time-matched sedentary rats served as controls. After euthanasia, heart hypertrophy was evaluated by histological studies; ventricular collagen deposition was quantified by histological and biochemical studies; and messenger RNA and protein expression of transforming growth factor-β1, fibronectin-1, matrix metalloproteinase-2, tissue inhibitor of metalloproteinase-1, procollagen-I and procollagen-III was evaluated in all 4 cardiac chambers. Daily intensive exercise caused hypertrophy in the left ventricular heart wall and originated collagen deposition in the right ventricle. Additionally long-term intensive exercise induced a significant increase in messenger RNA expression and protein synthesis of the major fibrotic markers in both atria and in the right ventricle. Losartan treatment was able to reduce all increases in messenger RNA expression and protein levels caused by exercise, although it could not completely reverse the heart hypertrophy. CONCLUSIONS: Losartan treatment prevents the heart fibrosis induced by endurance exercise in training animals.

  1. AFFECTIVE RESPONSES AFTER DIFFERENT INTENSITIES OF EXERCISE IN PATIENTS WITH TRAUMATIC BRAIN INJURY

    Directory of Open Access Journals (Sweden)

    Patricia eRzezak

    2015-06-01

    Full Text Available BACKGROUND: Patients with traumatic brain injury (TBI usually have mood and anxiety symptoms secondary to their brain injury. Exercise may be a cost-effective intervention for the regulation of the affective responses of this population. However, there are no studies evaluating the effects of exercise or the optimal intensity of exercise for this clinical group. METHODS: Twelve male patients with moderate or severe TBI [mean age of 31.83 and SD of 9.53] and 12 age- and gender-matched healthy volunteers [mean age of 30.58 and SD of 9.53] participated in two sessions of exercise of high and moderate intensity. Anxiety and mood was evaluated, and subjective assessment of experience pre- and post-exercise was assessed. A mixed between and within-subjects GLM analysis was conducted to compare groups [TBI, control] over condition [baseline, session 1, session 2] allowing for group by condition interaction to be determined. Planned comparisons were also conducted to test study hypotheses.RESULTS: Although no group by condition interaction was observed, planned comparisons indicated that baseline differences between patients and controls in anxiety (Cohens’ d=1.80, tension (d=1.31, depression (d=1.18, anger (d=1.08, confusion (d=1.70, psychological distress (d=1.28 and physical symptoms (d=1.42 disappear after one session of exercise, independently of the intensity of exercise. CONCLUSIONS: A single-section of exercise, regardless of exercise intensity, had a positive effect on the affective responses of patients with TBI both by increasing positive valence feelings and decreasing negative ones. Exercise can be an easily accessible intervention that may alleviate depressive symptoms related to brain injury.

  2. Affective responses after different intensities of exercise in patients with traumatic brain injury.

    Science.gov (United States)

    Rzezak, Patricia; Caxa, Luciana; Santolia, Patricia; Antunes, Hanna K M; Suriano, Italo; Tufik, Sérgio; de Mello, Marco T

    2015-01-01

    Patients with traumatic brain injury (TBI) usually have mood and anxiety symptoms secondary to their brain injury. Exercise may be a cost-effective intervention for the regulation of the affective responses of this population. However, there are no studies evaluating the effects of exercise or the optimal intensity of exercise for this clinical group. Twelve male patients with moderate or severe TBI [mean age of 31.83 and SD of 9.53] and 12 age- and gender-matched healthy volunteers [mean age of 30.58 and SD of 9.53] participated in two sessions of exercise of high and moderate-intensity. Anxiety and mood was evaluated, and subjective assessment of experience pre- and post-exercise was assessed. A mixed between and within-subjects general linear model (GLM) analysis was conducted to compare groups [TBI, control] over condition [baseline, session 1, session 2] allowing for group by condition interaction to be determined. Planned comparisons were also conducted to test study hypotheses. Although no group by condition interaction was observed, planned comparisons indicated that baseline differences between patients and controls in anxiety (Cohens' d = 1.80), tension (d = 1.31), depression (d = 1.18), anger (d = 1.08), confusion (d = 1.70), psychological distress (d = 1.28), and physical symptoms (d = 1.42) disappear after one session of exercise, independently of the intensity of exercise. A single-section of exercise, regardless of exercise intensity, had a positive effect on the affective responses of patients with TBI both by increasing positive valence feelings and decreasing negative ones. Exercise can be an easily accessible intervention that may alleviate depressive symptoms related to brain injury.

  3. The effect of exercise intensity on endothelial function in physically inactive lean and obese adults.

    Directory of Open Access Journals (Sweden)

    Rachel Hallmark

    Full Text Available To examine the effects of exercise intensity on acute changes in endothelial function in lean and obese adults.Sixteen lean (BMI 30, age 26 ± 6 yr physically inactive adults were studied during 3 randomized admissions [control (C, no exercise, moderate-intensity exercise (M, @ lactate threshold (LT and high-intensity exercise (H, midway between LT and VO2peak (30 min]. Endothelial function was assessed by flow-mediated dilation (FMD at baseline and 1, 2, and 4 h post-exercise.RM ANCOVA revealed significant main effects for group, time, and group x condition interaction (p<0.05. A diurnal increase in FMD was observed in lean but not obese subjects. Lean subjects exhibited greater increases in FMD than obese subjects (p = 0.0005. In the obese group a trend was observed for increases in FMD at 2- and 4-hr after M (p = 0.08. For lean subjects, FMD was significantly elevated at all time points after H. The increase in FMD after H in lean subjects (3.2 ± 0.5% was greater than after both C (1.7 ± 0.4%, p = 0.015 and M (1.4 ± 0.4%, p = 0.002. FMD responses of lean and obese subjects significantly differed after C and H, but not after M.In lean young adults, high-intensity exercise acutely enhances endothelial function, while moderate-intensity exercise has no significant effect above that seen in the absence of exercise. The FMD response of obese adults is blunted compared to lean adults. Diurnal variation should be considered when examining the effects of acute exercise on FMD.

  4. Effects of resistance exercise bouts of different intensities but equal work on EPOC.

    Science.gov (United States)

    Thornton, M Kathleen; Potteiger, Jeffery A

    2002-04-01

    To compare the effect of low- and high-intensity resistance exercise of equal work output, on exercise and excess postexercise oxygen consumption (EPOC). Fourteen female subjects performed a no-exercise baseline control (CN), and nine exercises for two sets of 15 repetitions at 45% of their 8-RM during one session (LO) and two sets of 8 repetitions at 85% of their 8-RM during another session (HI). Measures for all three sessions included: heart rate (HR) and blood lactate (La) preexercise, immediately postexercise and 20 min, 60 min, and 120 min postexercise; and ventilation volume (VE), oxygen consumption (VO(2)), and respiratory exchange ratio (RER) during exercise and at intervals 0-20 min, 45-60 min, and 105-120 min postexercise. Exercise .VO(2) was not significantly different between HI and LO, but VE, [La], and HR were significantly greater for HI compared with LO. Exercise RER for HI (1.07 +/- 0.03 and LO (1.05 +/- 0.02) were significantly higher than CN (0.86 +/- 0.02), but there were no differences among conditions postexercise. EPOC was greater for HI compared with low at 0-20 min (HI,1.72 +/- 0.70 LO(2); LO, 0.9 +/- 0.65, LO(2)), 45-60 min (HI, 0.35 +/- 0.25 LO(2); LO, 0.14 +/- 0.19 LO2), and 105-120 min (HI, 0.22 +/- 0.22 LO(2); LO, 0.05 +/- 0.11, LO(2)). These data indicate that for resistance exercise bouts with an equated work volume, high-intensity exercise (85% 8-RM) will produce similar exercise oxygen consumption, with a greater EPOC magnitude and volume than low-intensity exercise (45% 8-RM).

  5. Moderate vs. high exercise intensity: differential effects on aerobic fitness, cardiomyocyte contractility, and endothelial function.

    Science.gov (United States)

    Kemi, Ole J; Haram, Per M; Loennechen, Jan P; Osnes, Jan-Bjørn; Skomedal, Tor; Wisløff, Ulrik; Ellingsen, Øyvind

    2005-07-01

    Current guidelines are controversial regarding exercise intensity in cardiovascular prevention and rehabilitation. Although high-intensity training induces larger increases in fitness and maximal oxygen uptake (VO(2max)), moderate intensity is often recommended as equally effective. Controlled preclinical studies and randomized clinical trials are required to determine whether regular exercise at moderate versus high intensity is more beneficial. We therefore assessed relative effectiveness of 10-week HIGH versus moderate (MOD) exercise intensity on integrative and cellular functions. Sprague-Dawley rats performed treadmill running intervals at either 85%-90% (HIGH) or 65%-70% (MOD) of VO2max 1 h per day, 5 days per week. Weekly VO2max-testing adjusted exercise intensity. HIGH and MOD increased VO2max by 71% and 28%, respectively. This was paralleled by intensity-dependent cardiomyocyte hypertrophy, 14% and 5% in HIGH and MOD, respectively. Cardiomyocyte function (fractional shortening) increased by 45% and 23%, contraction rate decreased by 43% and 39%, and relaxation rate decreased by 20% and 10%, in HIGH and MOD, respectively. Ca2+ transient time-courses paralleled contraction/relaxation, whereas Ca2+ sensitivity increased 40% and 30% in HIGH and MOD, respectively. Carotid artery endothelial function improved similarly with both intensities. EC50 for acetylcholine-induced relaxation decreased 4.3-fold in HIGH (p hypertrophy, contractility and vasorelaxation also correlated significantly with VO2max. The present study demonstrates that cardiovascular adaptations to training are intensity-dependent. A close correlation between VO2max, cardiomyocyte dimensions and contractile capacity suggests significantly higher benefit with high intensity, whereas endothelial function appears equivalent at moderate levels. Thus, exercise intensity emerges as an important variable in future preclinical and clinical investigations.

  6. Differential effects of exercise intensities in hippocampal BDNF, inflammatory cytokines and cell proliferation in rats during the postnatal brain development

    OpenAIRE

    Almeida, Alexandre Aparecido de [UNIFESP; Gomes da Silva, Sérgio; Fernandes, Jansen; Peixinho-Pena, Luiz Fernando; Scorza, Fulvio Alexandre; Cavalheiro, Esper Abrão; Arida, Ricardo Mario

    2013-01-01

    It has been established that low intensities of exercise produce beneficial effects for the brain, while high intensities can cause some neuronal damage (e.g. exacerbated inflammatory response and cell death). Although these effects are documented in the mature brain, the influence of exercise intensities in the developing brain has been poorly explored. To investigate the impact of exercise intensity in developing rats, we evaluated the hippocampal level of brain derived neurotrophic factor ...

  7. Oxidative stress and antioxidant responses to progressive resistance exercise intensity in trained and untrained males.

    Science.gov (United States)

    Çakır-Atabek, H; Özdemir, F; Çolak, R

    2015-11-01

    The relationship between oxidative stress and some exercise components of resistance exercise (e.g. intensity, exercise volume) has not been clearly defined. Additionally, the oxidative stress markers may respond differently in various conditions. This study aims to determine the effects of progressive intensity of resistance exercise (RE) on oxidative stress and antioxidants in trained and untrained men, and also to investigate the possible threshold intensity required to evoke oxidative stress. RE trained (N=8) and untrained (N=8) men performed the leg extension RE at progressive intensities standardized for total volume: 1x17 reps at 50% of one-repetition maximum (1RM); 1x14 reps at 60% of 1RM; 1x12 reps at 70% of 1RM; 2x5 reps at 80% of 1RM; and 3x3 reps at 90% of 1RM. Blood samples were drawn before (PRE) and immediately after each intensity, and after 30 minutes, 60 minutes and 24 hours following the RE. Lipid-hydroperoxide (LHP) significantly increased during the test and then decreased during the recovery in both groups (plevel was lower than PRE-LHP. Protein carbonyl (PCO) and superoxide dismutase (SOD) significantly increased (p 0.05). The results indicated that there was no significant training status x intensity interaction for examined variables (p > 0.05). Standardized volume of RE increased oxidative stress responses. Our study suggests that lower intensity (50%) is enough to increase LHP, whereas higher intensity (more than 80%) is required to evoke protein oxidation.

  8. Effect of Short-Term, High-Intensity Exercise on Anaerobic Threshold in Women.

    Science.gov (United States)

    Evans, Blanche W.

    This study investigated the effects of a six-week, high-intensity cycling program on anaerobic threshold (AT) in ten women. Subjects trained four days a week using high-intensity interval-type cycle exercises. Workouts included six 4-minute intervals cycling at 85 percent maximal oxygen uptake (VO sub 2 max), separated by 3-minute intervals of…

  9. Human skeletal muscle HSP70 response to physical training depends on exercise intensity.

    Science.gov (United States)

    Liu, Y; Lormes, W; Baur, C; Opitz-Gress, A; Altenburg, D; Lehmann, M; Steinacker, J M

    2000-07-01

    We have previously reported that HSP70 in human skeletal muscle could be induced by training. However, whether HSP70 induction is dependent upon exercise volume or exercise intensity remains unknown. The aim of the present study was to investigate the relationship between HSP70 and training intensity in rowers. Fourteen well-trained male rowers were divided into two groups (group A, n = 6; group B, n = 8). Group A performed higher intensity exercise during 1st phase, whereas group B performed higher intensity exercise during 2nd training phase. Training volume in 2nd phase increased in both groups. Both training intensity and volume were reduced in 3rd phase. Muscle samples were taken from m. vastus lateralis by fine needle biopsy before training, at the end of the 1st, 2nd and 3rd training phases. HSP70 was quantitatively determined using SDS-PAGE with silver stain. In group A, HSP70 increased significantly from 38 +/- 12 etag before training to 59 +/- 16 etag at the end of the lst training phase (loaded total protein 2.5microg), and decreased afterwards. In group B, HSP70 increase (from 36 +/- 11 etag to 50 +/- 13 etag) in the 1st phase was significantly smaller, there was a further increase of HSP70 in the 2nd phase (60 +/- 14 etag). At the end of the training, HSP70 decreased in both groups. Thus, HSP70 response to training seems to be dependent upon exercise intensity.

  10. Physiological adaptations to interval training and the role of exercise intensity.

    Science.gov (United States)

    MacInnis, Martin J; Gibala, Martin J

    2017-05-01

    Interval exercise typically involves repeated bouts of relatively intense exercise interspersed by short periods of recovery. A common classification scheme subdivides this method into high-intensity interval training (HIIT; 'near maximal' efforts) and sprint interval training (SIT; 'supramaximal' efforts). Both forms of interval training induce the classic physiological adaptations characteristic of moderate-intensity continuous training (MICT) such as increased aerobic capacity (V̇O2 max ) and mitochondrial content. This brief review considers the role of exercise intensity in mediating physiological adaptations to training, with a focus on the capacity for aerobic energy metabolism. With respect to skeletal muscle adaptations, cellular stress and the resultant metabolic signals for mitochondrial biogenesis depend largely on exercise intensity, with limited work suggesting that increases in mitochondrial content are superior after HIIT compared to MICT, at least when matched-work comparisons are made within the same individual. It is well established that SIT increases mitochondrial content to a similar extent to MICT despite a reduced exercise volume. At the whole-body level, V̇O2 max is generally increased more by HIIT than MICT for a given training volume, whereas SIT and MICT similarly improve V̇O2 max despite differences in training volume. There is less evidence available regarding the role of exercise intensity in mediating changes in skeletal muscle capillary density, maximum stroke volume and cardiac output, and blood volume. Furthermore, the interactions between intensity and duration and frequency have not been thoroughly explored. While interval training is clearly a potent stimulus for physiological remodelling in humans, the integrative response to this type of exercise warrants further attention, especially in comparison to traditional endurance training. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

  11. Caffeine intake improves intense intermittent exercise performance and reduces muscle interstitial potassium accumulation

    DEFF Research Database (Denmark)

    Mohr, Magni; Nielsen, Jens Jung; Bangsbo, Jens

    2011-01-01

    The effect of oral caffeine ingestion on intense intermittent exercise performance and muscle interstitial ion concentrations was examined. The study consists of two studies (S1 and S2). In S1 twelve subjects completed the Yo-Yo intermittent recovery level 2 (Yo-Yo IR2) test with prior caffeine (6...... mg/kg b.w.; CAF) or placebo (PLA) intake. In S2 six subjects performed one low intense (20 W) and three intense (50 W) 3-min (separated by 5 min) one-legged knee-extension exercise bouts with (CAF) and without (CON) prior caffeine supplementation for determination of muscle interstitial K(+) and Na...

  12. Acute Impact of Moderate-Intensity and Vigorous-Intensity Exercise Bouts on Daily Physical Activity Energy Expenditure in Postmenopausal Women

    Directory of Open Access Journals (Sweden)

    Xuewen Wang

    2011-01-01

    Full Text Available This study determined whether performing a single moderate- or vigorous-intensity exercise bout impacts daily physical activity energy expenditure (PAEE, by accelerometer. Overweight/obese postmenopausal women underwent a 5-month caloric restriction and moderate- (n=18 or vigorous-intensity (n=18 center-based aerobic exercise intervention. During the last month of intervention, in women performing moderate-intensity exercise, PAEE on days with exercise (577.7±219.7 kcal⋅d−1 was higher (P=.011 than on days without exercise (450.7±140.5 kcal⋅d−1; however, the difference (127.0±188.1 kcal⋅d−1 was much lower than the energy expended during exercise. In women performing vigorous-intensity exercise, PAEE on days with exercise (450.6±153.6 kcal⋅d−1 was lower (P=.047 than on days without exercise (519.2±127.4 kcal⋅d−1. Thus, women expended more energy on physical activities outside of prescribed exercise on days they did NOT perform center-based exercise, especially if the prescribed exercise was of a higher intensity.

  13. 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

  14. Acute molecular responses to concurrent resistance and high-intensity interval exercise in untrained skeletal muscle

    Science.gov (United States)

    Pugh, Jamie K; Faulkner, Steve H; Jackson, Andrew P; King, James A; Nimmo, Myra A

    2015-01-01

    Concurrent training involving resistance and endurance exercise may augment the benefits of single-mode training for the purpose of improving health. However, muscle adaptations, associated with resistance exercise, may be blunted by a subsequent bout of endurance exercise, via molecular interference. High-intensity interval training (HIIT), generating similar adaptations to endurance exercise, may offer an alternative exercise mode to traditional endurance exercise. This study examined the influence of an acute HIIT session on the molecular responses following resistance exercise in untrained skeletal muscle. Ten male participants performed resistance exercise (4 × 8 leg extensions, 70% 1RM, (RE)) or RE followed by HIIT (10 × 1 min at 90% HRmax, (RE+HIIT)). Muscle biopsies were collected from the vastus lateralis before, 2 and 6 h post-RE to determine intramuscular protein phosphorylation and mRNA responses. Phosphorylation of Akt (Ser473) decreased at 6 h in both trials (P HIIT (P HIIT with PGC-1α and PGC-1α-ex1b remaining elevated at 6 h, whereas RE-induced increases at 2 and 6 h for PGC-1α-ex1b only (P HIIT versus RE at 2 and 6 h (P HIIT may be an alternative to endurance exercise when performed after resistance exercise in the same training session to optimize adaptations. PMID:25902785

  15. Increased mortality in patients with severe COPD associated with high-intensity exercise

    DEFF Research Database (Denmark)

    Schaadt, Lone; Christensen, Robin; Kristensen, Lars Erik

    2016-01-01

    INTRODUCTION: Intensity of exercise is believed to be a key determinant of response to chronic obstructive pulmonary disease (COPD) rehabilitation. We hypothesized that a higher intensity of exercise, in combination with physiotherapist-led instructions and education in management of breathlessness...... prospective cohort study on severe COPD patients referred to outpatient rehabilitation. METHODS: In 2013, four rehabilitation courses were scheduled (spring, summer, autumn, and winter) each lasting 8 weeks and including eight to ten patients. This preliminary study was designed as a controlled cohort study...... assessed from the participants' medical records in an 18-month period. RESULTS: We were able to enroll 31 patients in total (15 in the high-intensity exercise group and 16 in regular intensity). There were no group differences in the hospitalization rates. However, during review of the medical records, we...

  16. Effects of myofascial release after high-intensity exercise: a randomized clinical trial.

    Science.gov (United States)

    Arroyo-Morales, Manuel; Olea, Nicolas; Martinez, Manuel; Moreno-Lorenzo, Carmen; Díaz-Rodríguez, Lourdes; Hidalgo-Lozano, Amparo

    2008-03-01

    The usefulness of massage as a recovery method after high-intensity exercise has yet to be established. We aimed to investigate the effects of whole-body massage on heart rate variability (HRV) and blood pressure (BP) after repeated high-intensity cycling exercise under controlled and standardized pretest conditions. The study included 62 healthy active individuals. After baseline measurements, the subjects performed standardized warm-up exercises followed by three 30-second Wingate tests. After completing the exercise protocol, the subjects were randomly assigned to a massage (myofascial release) or placebo (sham treatment with disconnected ultrasound and magnetotherapy equipment) group for a 40-minute recovery period. Holter recording and BP measurements were taken after exercise protocol and after the intervention. After the exercise protocol, both groups showed a significant decrease in normal-to-normal interval, HRV index, diastolic BP (P > .001), and low-frequency domain values (P = .006). After the recovery period, HRV index (P = .42) and high-frequency (HF) (P = .94) values were similar to baseline levels in the massage group, whereas the HRV index tended (P = .05) to be lower and the HF was significantly (P Myofascial release massage favors the recovery of HRV and diastolic BP after high-intensity exercise (3 Wingate tests) to preexercise levels.

  17. Endothelial dysfunction induced by postprandial lipemia: Complete protection afforded by high intensity aerobic interval exercise

    Science.gov (United States)

    Tyldum, Gjertrud Aunet; Schjerve, Inga Ekeberg; Tjønna, Arnt Erik; Kirkeby-Garstad, Idar; Stølen, Tomas O.; Richardson, Russell S.; Wisløff, Ulrik

    2009-01-01

    Objectives To study the effect of exercise and a high fat meal (HFM) on endothelial function. Background Postprandial lipemia and exercise oppose each other in terms of cardiovascular risk, however the mechanism of their interaction is not well understood. Methods Endothelial function was assessed by brachial artery flow mediated dilation (FMD), in eight healthy men before and after a HFM preceded (16–18 hrs) by rest, a single bout of continuous moderate intensity exercise (CME), and high intensity interval exercise (HIIE). Results Before the HFM, initial brachial artery diameters were similar in all trials (0.43±0.04 cm), but after the HFM basal diameter decreased only in the control (0.39±0.03) and CME (0.38±0.04) trials. Prior to the HFM, FMD/shear was improved by a single bout of CME (+20%, plipemia. Although, there were no correlations between vascular function and food-induced markers of cardiovascular risk, antioxidant status was strongly correlated with FMD (r=0.9, p<0.001). Conclusion These findings reveal a clinically relevant protective effect of acute exercise upon the vasculature that is clearly exercise intensity dependent and tightly related to exercise-induced antioxidant capacity. PMID:19130989

  18. Low and moderate, rather than high intensity strength exercise induces benefit regarding plasma lipid profile

    Directory of Open Access Journals (Sweden)

    Lira Fabio S

    2010-05-01

    Full Text Available Abstract Background The effects of chronic aerobic exercise upon lipid profile has been previously demonstrated, but few studies showed this effect under resistance exercise conditions. Objective The aim of this study was to examine the effects of different resistance exercise loads on blood lipids. Methods Thirty healthy, untrained male volunteers were allocated randomly into four groups based at different percentages of one repetition maximum (1 RM; 50%-1 RM, 75%-1 RM, 90%-1 RM, and 110%-1 RM. The total volume (sets × reps × load of the exercise was equalized. The lipid profile (Triglycerides [TG], HDL-cholesterol [HDL-c], LDL-cholesterol, and Total cholesterol was determined at rest and after 1, 24, 48 and 72 h of resistance exercise. Results The 75%-1 RM group demonstrated greater TG reduction when compared to other groups (p Conclusion These results indicate that the acute resistance exercise may induce changes in lipid profile in a specific-intensity manner. Overall, low and moderate exercise intensities appear to be promoting more benefits on lipid profile than high intensity. Long term studies should confirm these findings.

  19. Estimated Aerobic Capacity Changes in Adolescents with Obesity Following High Intensity Interval Exercise

    Directory of Open Access Journals (Sweden)

    Brooke E. Starkoff

    2014-07-01

    Full Text Available Vigorous aerobic exercise may improve aerobic capacity (VO2max and cardiometabolic profiles in adolescents with obesity, independent of changes to weight. Our aim was to assess changes in estimated VO2max in obese adolescents following a 6-week exercise program of varying intensities. Adolescents with obesity were recruited from an American mid-west children’s hospital and randomized into moderate exercise (MOD or high intensity interval exercise (HIIE groups for a 6-week exercise intervention, consisting of cycle ergometry for 40 minutes, 3 days per week. Heart rate was measured every two minutes during each exercise session.  Estimated VO2max measured via Åstrand cycle test, body composition, and physical activity (PA enjoyment evaluated via questionnaire were assessed pre/post-intervention. Twenty-seven adolescents (age 14.7±1.5; 17 female, 10 male completed the intervention. Estimated VO2max increased only in the HIIE group (20.0±5.7 to 22.7±6.5 ml/kg/min, p=0.015. The HIIE group also demonstrated increased PA enjoyment, which was correlated with average heart rate achieved during the intervention (r=0.55; p=0.043. Six weeks of HIIE elicited improvements to estimated VO2max in adolescents with obesity. Furthermore, those exercising at higher heart rates demonstrated greater PA enjoyment, implicating enjoyment as an important determinant of VO2max, specifically following higher intensity activities.

  20. Exercise Intensity Guidelines for Cancer Survivors: a Comparison with Reference Values.

    Science.gov (United States)

    Gil-Rey, E; Quevedo-Jerez, K; Maldonado-Martin, S; Herrero-Román, F

    2014-11-27

    The optimal dose of physical activity (PA) in cancer survivors (CS) is unknown due to the large variety of types of cancer, illness stages and treatments, low cardiorespiratory fitness, and physical inactivity. It is recommended that CS follow current PA guidelines for healthy population. There are no specific exercise prescription guidelines for CS. To know the cardiorespiratory parameters of CS in order to create exercise prescription guidelines for this population, 152 inactive CS were recruited to perform a cardiopulmonary exercise test. Peak oxygen uptake (VO 2peak ), ventilatory threshold (VT) and respiratory compensation point (RCP) determined 3 exercise intensity zones to create exercise intensity classification guidelines for CS. VO 2peak (18.7±4.6 mL·kg -1 ·min -1 ) and peak heart rate (HR peak ) (145.1±17.9 bpm) were lower than the estimated values (phealthy population: 41-64% VO 2max , 55-70% HR max , 23-48% HR res , 2.5-4 METs and 8-14 points on RPE scale. Intensities in PA guidelines for healthy population are not adapted to the characteristics of CS. For individual exercise prescription in CS specific PA guidelines should be used in order to maximize the benefits obtained by the use of aerobic exercise training. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Fatiguing exercise intensity influences the relationship between parameters reflecting neuromuscular function and postural control variables.

    Directory of Open Access Journals (Sweden)

    Sébastien Boyas

    Full Text Available The purpose of this study was to investigate the influence of fatiguing exercise intensity on the nature and extent of fatigue-induced changes in neuromuscular function and postural stability in quiet standing. We also explored the contribution of selected neuromuscular mechanisms involved in force production to postural stability impairment observed following fatigue using an approach based on multivariate regressions. Eighteen young subjects performed 30-s postural trials on one leg with their eyes closed. Postural trials were performed before and after fatiguing exercises of different intensities: 25, 50 and 75% of maximal isometric plantarflexor torque. Fatiguing exercises consisted of sustaining a plantarflexor isometric contraction at the target intensity until task failure. Maximal isometric plantarflexor torque, electromyographic activity of plantarflexor and dorsiflexor muscles, activation level (twitch interpolation technique and twitch contractile properties of plantarflexors were used to characterize neuromuscular function. The 25% exercise was associated with greater central fatigue whereas the 50 and 75% exercises involved mostly peripheral fatigue. However, all fatiguing exercises induced similar alterations in postural stability, which was unexpected considering previous literature. Stepwise multiple regression analyses showed that fatigue-related changes in selected parameters related to neuromuscular function could explain more than half (0.51≤R(2≤0.82 of the changes in postural variables for the 25% exercise. On the other hand, regression models were less predictive (0.17≤R(2≤0.73 for the 50 and 75% exercises. This study suggests that fatiguing exercise intensity does not influence the extent of postural stability impairment, but does influence the type of fatigue induced and the neuromuscular function predictors explaining changes in postural variables.

  2. Effects of exercise intensity on plasma concentrations of appetite-regulating hormones: Potential mechanisms.

    Science.gov (United States)

    Hazell, Tom J; Islam, Hashim; Townsend, Logan K; Schmale, Matt S; Copeland, Jennifer L

    2016-03-01

    The physiological control of appetite regulation involves circulating hormones with orexigenic (appetite-stimulating) and anorexigenic (appetite-inhibiting) properties that induce alterations in energy intake via perceptions of hunger and satiety. As the effectiveness of exercise to induce weight loss is a controversial topic, there is considerable interest in the effect of exercise on the appetite-regulating hormones such as acylated ghrelin, peptide YY (PYY), glucagon-like peptide-1 (GLP-1), and pancreatic polypeptide (PP). Research to date suggests short-term appetite regulation following a single exercise session is likely affected by decreases in acylated ghrelin and increases in PYY, GLP-1, and PP. Further, this exercise-induced response may be intensity-dependent. In an effort to guide future research, it is important to consider how exercise alters the circulating concentrations of these appetite-regulating hormones. Potential mechanisms include blood redistribution, sympathetic nervous system activity, gastrointestinal motility, cytokine release, free fatty acid concentrations, lactate production, and changes in plasma glucose and insulin concentrations. This review of relevant research suggests blood redistribution during exercise may be important for suppressing ghrelin, while other mechanisms involving cytokine release, changes in plasma glucose and insulin concentrations, SNS activity, and muscle metabolism likely mediate changes in the anorexigenic signals PYY and GLP-1. Overall, changes in appetite-regulating hormones following acute exercise appear to be intensity-dependent, with increasing intensity leading to a greater suppression of orexigenic signals and greater stimulation of anorexigenic signals. However, there is less research on how exercise-induced responses in appetite-regulating hormones differ between sexes or different age groups. A better understanding of how exercise intensity and workload affect appetite across the sexes and life

  3. Exercise Guidelines to Promote Cardiometabolic Health in Spinal Cord Injured Humans: Time to Raise the Intensity?

    Science.gov (United States)

    Nightingale, Tom E; Metcalfe, Richard S; Vollaard, Niels B; Bilzon, James L

    2017-08-01

    Spinal cord injury (SCI) is a life-changing event that, as a result of paralysis, negatively influences habitual levels of physical activity and hence cardiometabolic health. Performing regular structured exercise therefore appears extremely important in persons with SCI. However, exercise options are mainly limited to the upper body, which involves a smaller activated muscle mass compared with the mainly leg-based activities commonly performed by nondisabled individuals. Current exercise guidelines for SCI focus predominantly on relative short durations of moderate-intensity aerobic upper-body exercise, yet contemporary evidence suggests this is not sufficient to induce meaningful improvements in risk factors for the prevention of cardiometabolic disease in this population. As such, these guidelines and their physiological basis require reappraisal. In this special communication, we propose that high-intensity interval training (HIIT) may be a viable alternative exercise strategy to promote vigorous-intensity exercise and prevent cardiometabolic disease in persons with SCI. Supplementing the limited data from SCI cohorts with consistent findings from studies in nondisabled populations, we present strong evidence to suggest that HIIT is superior to moderate-intensity aerobic exercise for improving cardiorespiratory fitness, insulin sensitivity, and vascular function. The potential application and safety of HIIT in this population is also discussed. We conclude that increasing exercise intensity could offer a simple, readily available, time-efficient solution to improve cardiometabolic health in persons with SCI. We call for high-quality randomized controlled trials to examine the efficacy and safety of HIIT in this population. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. Oxidative stress and antioxidant responses to progressive resistance exercise intensity in trained and untrained males

    Directory of Open Access Journals (Sweden)

    H Çakır-Atabek

    2015-11-01

    Full Text Available The relationship between oxidative stress and some exercise components of resistance exercise (e.g. intensity, exercise volume has not been clearly defined. Additionally, the oxidative stress markers may respond differently in various conditions. This study aims to determine the effects of progressive intensity of resistance exercise (RE on oxidative stress and antioxidants in trained and untrained men, and also to investigate the possible threshold intensity required to evoke oxidative stress. RE trained (N=8 and untrained (N=8 men performed the leg extension RE at progressive intensities standardized for total volume: 1x17 reps at 50% of one-repetition maximum (1RM; 1x14 reps at 60% of 1RM; 1x12 reps at 70% of 1RM; 2x5 reps at 80% of 1RM; and 3x3 reps at 90% of 1RM. Blood samples were drawn before (PRE and immediately after each intensity, and after 30 minutes, 60 minutes and 24 hours following the RE. Lipid-hydroperoxide (LHP significantly increased during the test and then decreased during the recovery in both groups (p0.05. Standardized volume of RE increased oxidative stress responses. Our study suggests that lower intensity (50% is enough to increase LHP, whereas higher intensity (more than 80% is required to evoke protein oxidation.

  5. Influence of prior intense exercise and cold water immersion in recovery for performance and physiological response during subsequent exercise

    DEFF Research Database (Denmark)

    Christensen, Peter Møller; Bangsbo, Jens

    2016-01-01

    Athletes in intense endurance sports (e.g., 4000-m track cycling) often perform maximally (~4 min) twice a day due to qualifying and finals being placed on the same day. The purpose of the present study was to evaluate repeated performance on the same day in a competitive setting (part A) and the......Athletes in intense endurance sports (e.g., 4000-m track cycling) often perform maximally (~4 min) twice a day due to qualifying and finals being placed on the same day. The purpose of the present study was to evaluate repeated performance on the same day in a competitive setting (part A......, mean power in PT was not different in CWI relative to CON (406 ± 43 vs. 405 ± 38 W). Peak ⩒O2 (5.04 ± 0.50 vs. 5.00 ± 0.49 L/min) and blood lactate (13 ± 3 vs. 14 ± 3 mmol/L) did not differ between QUAL and PT and cycling economy and potassium handling was not impaired by prior intense exercise....... In conclusion, performance is reduced with repeated maximal exercise in world-class track cyclists during 4000-m individual pursuit lasting ~4 min, however prior intense exercise do not appear to impair peak ⩒O2, peak lactate, cycling economy, or potassium handling in trained cyclists and CWI in recovery does...

  6. Exercise training intensity prescription in breast cancer survivors: validity of current practice and specific recommendations.

    Science.gov (United States)

    Scharhag-Rosenberger, Friederike; Kuehl, Rea; Klassen, Oliver; Schommer, Kai; Schmidt, Martina E; Ulrich, Cornelia M; Wiskemann, Joachim; Steindorf, Karen

    2015-12-01

    Cancer survivors are recommended to perform 150 min/week of moderate or 75 min/week of vigorous aerobic exercise, but it remains unclear how moderate and vigorous intensities can be prescribed. Therefore, it was investigated whether and how intensity prescriptions for healthy adults by the American College of Sports Medicine (ACSM) need to be adapted for breast cancer survivors. Fifty-two breast cancer survivors (stage 0-III, age 52 ± 9 years, BMI 25.4 ± 3.5 kg/m2) performed cardiopulmonary exercise tests at the end of primary therapy. Intensity classes defined as percentages of maximal heart rate (HRmax), heart rate reserve (HRR), and maximal oxygen uptake (VO2max) were compared to the ACSM's intensity classes using oxygen uptake reserve as reference. The prescriptions for moderate and vigorous exercise intensities were significantly different between breast cancer survivors and healthy adults when using VO2max (moderate 50-66 vs. 46-63 and vigorous 67-91 vs. 64-90% VO2max) or HRR (moderate 26-50 vs. 40-59 and vigorous 51-88 vs. 60-89 % HRR), but not when using HRmax (moderate 65-76 vs. 64-76 and vigorous 77-94 vs. 77-95% HRmax). In breast cancer survivors, intensity prescriptions for healthy adults result in considerably too intense training if HRR is used as guiding factor. Prescriptions using VO2max result in a slightly too low exercise intensity, whereas recommendations in percentages of HRmax appear valid. Cancer survivors should not uncritically adopt exercise intensity prescriptions for healthy adults. Specific prescriptions for the studied population are provided.

  7. Effect of exercise intensity and volume on persistence of insulin sensitivity during training cessation.

    Science.gov (United States)

    Bajpeyi, Sudip; Tanner, Charles J; Slentz, Cris A; Duscha, Brian D; McCartney, Jennifer S; Hickner, Robert C; Kraus, William E; Houmard, Joseph A

    2009-04-01

    The purpose of this study was to determine whether exercise prescriptions differing in volume or intensity also differ in their ability to retain insulin sensitivity during an ensuing period of training cessation. Sedentary, overweight/obese subjects were assigned to one of three 8-mo exercise programs: 1) low volume/moderate intensity [equivalent of approximately 12 miles/wk, 1,200 kcal/wk at 40-55% peak O(2) consumption (Vo(2peak)), 200 min exercise/wk], 2) low volume/vigorous intensity ( approximately 12 miles/wk, 1,200 kcal/wk at 65-80% Vo(2peak), 125 min/wk), and 3) high volume/vigorous intensity ( approximately 20 miles/wk, 2,000 kcal/wk at 65-80% Vo(2peak), 200 min/wk). Insulin sensitivity (intravenous glucose tolerance test, S(I)) was measured when subjects were sedentary and at 16-24 h and 15 days after the final training bout. S(I) increased with training compared with the sedentary condition (P training cessation in the low-volume/vigorous-intensity group. In contrast, at 15 days S(I) was significantly elevated compared with sedentary (P volume/moderate intensity, high volume/vigorous intensity). In the high-volume/vigorous-intensity group, indexes of muscle mitochondrial density followed a pattern paralleling insulin action by being elevated at 15 days compared with pretraining; this trend was not evident in the low-volume/moderate-intensity group. These findings suggest that in overweight/obese subjects a relatively chronic persistence of enhanced insulin action may be obtained with endurance-oriented exercise training; this persistence, however, is dependent on the characteristics of the exercise training performed.

  8. The effects of creatine pyruvate and creatine citrate on performance during high intensity exercise

    Directory of Open Access Journals (Sweden)

    Purpura Martin

    2008-02-01

    Full Text Available Abstract Background A double-blind, placebo-controlled, randomized study was performed to evaluate the effect of oral creatine pyruvate (Cr-Pyr and creatine citrate (Cr-Cit supplementation on exercise performance in healthy young athletes. Methods Performance during intermittent handgrip exercise of maximal intensity was evaluated before (pretest and after (posttest 28 days of Cr-Pyr (5 g/d, n = 16, Cr-Cit (5 g/d, n = 16 or placebo (pla, 5 g/d, n = 17 intake. Subjects performed ten 15-sec exercise intervals, each followed by 45 sec rest periods. Results Cr-Pyr (p Conclusion It is concluded that four weeks of Cr-Pyr and Cr-Cit intake significantly improves performance during intermittent handgrip exercise of maximal intensity and that Cr-Pyr might benefit endurance, due to enhanced activity of the aerobic metabolism.

  9. Cortical Oxyhemoglobin Elevation Persists After Moderate-Intensity Cycling Exercise: A Near-Infrared Spectroscopy Study.

    Science.gov (United States)

    Tsubaki, Atsuhiro; Takehara, Nana; Sato, Daisuke; Morishita, Shinichiro; Tokunaga, Yuta; Sugawara, Kazuhiro; Kojima, Sho; Tamaki, Hiroyuki; Yamazaki, Yudai; Onishi, Hideaki

    2017-01-01

    Near-infrared spectroscopy (NIRS) can measure cortical activity during gross motor tasks based on the cerebral hemodynamic response. Although some reports suggest that cycling exercise improves cortical oxygenation, its after-effects are unknown. We examined the after-effects of low- and moderate-intensity cycling exercise on cortical oxygenation. Ten healthy volunteers (mean age 21.3 ± 0.7 years; 4 women) underwent cycle ergometer exercise at 30% or 50% of VO2peak for 20 min, followed by an 8-min post-exercise rest (PER). O2Hb levels of the supplementary motor area (SMA) and sensorimotor cortex (SMC) were recorded using a near-infrared spectroscopy system. Skin blood flow (SBF) and mean arterial pressure (MAP) were continuously measured. The peak values of O2Hb between exercise and PER were compared. The O2Hb, SBF, and MAP increased in the exercise phase. SBF degraded over time, and MAP decreased immediately after exercise. The O2Hb decreased immediately and increased again in the PER. There were no significant differences between exercise and PER in the SMC in the 30% VO2peak experiment or in the SMA and SMC in the 50% VO2peak experiment. The O2Hb in the motor-related area was elevated during both exercise and PER especially in the 50% VO2peak experiment.

  10. Electromyographic evaluation of high-intensity elastic resistance exercises for lower extremity muscles during bed rest.

    Science.gov (United States)

    Vinstrup, Jonas; Skals, Sebastian; Calatayud, Joaquin; Jakobsen, Markus Due; Sundstrup, Emil; Pinto, Matheus Daros; Izquierdo, Mikel; Wang, Yuling; Zebis, Mette K; Andersen, Lars Louis

    2017-07-01

    Prolonged hospital bed rest after severe injury or disease leads to rapid muscle atrophy and strength loss. Therefore, the main aim of this study was to evaluate the efficacy of lower extremity strengthening exercises using elastic resistance that can be performed while lying in a hospital bed. Using a cross-sectional design, 22 healthy individuals performed three consecutive repetitions of 14 different lower extremity exercises using elastic resistance, with a perceived intensity corresponding to 8 on the Borg CR-10 scale. Surface electromyography was measured on 13 lower extremity muscles and normalized to the maximal EMG (nEMG). Likewise, exercise satisfaction was evaluated by a questionnaire. All participants were able to perform all exercises without discomfort and generally rated them satisfactory. High levels of muscle activity were observed for all prime movers. For example, the "femoris muscle setting" exercise showed high levels of muscle activity for rectus femoris, vastus lateralis, and vastus medialis (79, 75, and 79% nEMG, respectively), while biceps femoris and semitendinosus were highly active during the prone knee flexion exercise with (72 and 71% nEMG, respectively) and without Kinesiology Tape (73 and 77% nEMG, respectively). High levels of muscle activity in the lower extremities can be achieved using elastic resistance exercises performed when lying in a hospital bed. Even though performed on healthy individuals, the present study has the potential to provide a reference table of exercises to select from when individualizing and progressing strengthening exercises during the early rehabilitation of bedridden individuals.

  11. A database for analysis of speech under physical stress: detection of exercise intensity while running and talking

    NARCIS (Netherlands)

    Truong, Khiet Phuong; Nieuwenhuys, Arne; Beek, Peter; Evers, Vanessa

    One of the ways to gauge your own exercise intensity while running, is to assess your capability of talking while running: if you can still speak comfortably, you are running within the recommended intensity guidelines. This subjective way of estimating one's exercise intensity by talking (i.e. the

  12. Absence of Respiratory Muscle Fatigue in High-Intensity Continuous or Interval Cycling Exercise.

    Science.gov (United States)

    Kurti, Stephanie P; Smith, Joshua R; Emerson, Sam R; Castinado, Kenneth M; Harms, Craig A

    2015-11-01

    Respiratory muscle fatigue (RMF) occurs during prolonged exercise (∼15-20 minutes) at >85% V[Combining Dot Above]O2max. However, RMF has been reported to occur in ∼3-6 minutes in various modes of exercise at a high intensity. It is not known if continuous cycling exercise vs. repeated bouts of high-intensity interval training (HIT) at >85% V[Combining Dot Above]O2max will lead to RMF. We hypothesized that RMF would occur after a constant load test and would be present before end exercise in an HIT protocol. Eight moderately active healthy men (21.7 ± 1.7 years; 181.3 ± 5.2 cm; 81.3 ± 2.3 kg) completed a V[Combining Dot Above]O2max test on a cycle ergometer. Subjects then completed 2 bouts of HIT (7 × 1 minute, 2-minute recovery between intervals) and 3 bouts of continuous exercise (CE) tests at 90% of peak power (determined from an incremental exercise test to exhaustion). Maximal inspiratory pressure (PIMAX) and expiratory pressure (PEMAX) were measured pre- and post-exercise for both HIT and CE and after each interval during HIT. Decreases in postexercise PIMAX and PEMAX compared with baseline were used to determine RMF. There were no differences (p > 0.05) in PIMAX or PEMAX pre- to post-exercise for HIT (PIMAX pre: 134 ± 51, post: 135 ± 50 cmH2O; PEMAX pre: 143 ± 41, post: 148 ± 46 cmH2O) or CE (PIMAX pre: 135 ± 54, post: 133 ± 52 cmH2O; PEMAX pre: 146 ± 46, post: 148 ± 46 cmH2O) indicating RMF was not present following CE and HIT. These data suggest that repeated high-intensity cycling exercise at 90% peak power in a CE or HIT protocol does not lead to RMF.

  13. Effects of exercise intensity on flow mediated dilation in healthy humans.

    Science.gov (United States)

    Birk, G K; Dawson, E A; Batterham, A M; Atkinson, G; Cable, T; Thijssen, D H J; Green, D J

    2013-05-01

    Previous studies have demonstrated conflicting results on the effects of acute exercise on FMD. The aim of the study was to examine brachial artery FMD before and after 3 bouts of acute exercise performed at different intensities. 10 healthy males (mean±SD age: 22±1 years) completed 30 min of cycling at 50, 70 and 85% maximal heart rate (HRmax). Brachial artery FMD and the shear rate area-under-the-curve (cuff deflation to peak dilation; SRAUC) were assessed pre- and immediately post-exercise using high-resolution echo-Doppler. A generalized estimating equation (GEE) analysis was used to estimate the effect magnitudes of exercise intensity and time (pre/post) on FMD, whilst controlling for the influence of baseline diameter and SRAUC. Both baseline diameter and SRAUC were elevated by exercise. With covariate-control of these variables, the decrease in brachial artery FMD was negligible after exercise at 50% HRmax (6.3±2.6 vs. 5.9±2.5%; 95%CI for difference: - 0.59-1.34%) with larger decreases in FMD after exercise at 70% (6.1±1.8 vs. 4.7±1.9%; 95%CI for difference: 0.08-2.58%) and at 85% HRmax (6.6±1.6 vs. 3.6±2.2%; 95%CI: 0.41-5.42%). In conclusion, even after accounting for exercise-mediated changes in shear and baseline diameter, our data indicate that a negative relationship exists between exercise intensity and FMD. © Georg Thieme Verlag KG Stuttgart · New York.

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

    DEFF Research Database (Denmark)

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

    1995-01-01

    This study examined the effect of glycogen supercompensation on glycogen breakdown, muscle and blood lactate accumulation, blood-pH, and performance during short-term high-intensity exercise. Young healthy volunteers performed two supramaximal (125% of VO2max) exercise tests on a bicycle ergometer......, either for 1 min 45 s (protocol 1; N = 18) or to exhaustion (protocol 2; N = 14). The exercise tests were preceded by either 5 d on a controlled normal (N) diet, or by 2 d of glycogen-depleting exercise accompanied by the normal diet followed by 3 d on a carbohydrate-rich (CHR) diet. In protocol 1......, preexercise muscle glycogen concentrations were 364 +/- 23 and 568 +/- 35 mumol.g-1 d.w. in the N and CHR condition, respectively (P glycogen concentration in the M. quadriceps decreased to the same extent in both groups. Accordingly, the exercise-induced increases in muscle...

  15. Increased intensity of a single exercise bout stimulates subsequent fat intake.

    Science.gov (United States)

    Klausen, B; Toubro, S; Ranneries, C; Rehfeld, J F; Holst, J J; Christensen, N J; Astrup, A

    1999-12-01

    The physical activity pattern in society has in recent years changed from necessary occupational activity to voluntary activities during leisure-time. How this change in lifestyle affects the selection of dietary intakes is presently unknown. The aim of the present study was to investigate the different effects of high vs. low-intensity exercise on the following day's dietary energy intake and macronutrient selection. The study was designed as a controlled randomized cross-over study which compared food selection and energy intake the day following a low-intensity vs a high-intensity exercise bout. We included 32 healthy normal-weight subjects of four subgroups (young males, young females, old males and old females). On two different occasions they performed either 60 min low-intensity (30% of VO2max) or 30 min high-intensity (60% of VO2max) exercise during 24h measurements of energy expenditure. The energy intake and macronutrient selection of the subsequent day was assessed by offering them an adlibitum buffet at breakfast and at lunch. Following the low-intensity exercise the subjects chose a diet with an energy percentage from fat similar to that of their habitual diet-36.7% (95% CI: 34.3, 39.0) vs 35.6% (95% CI: 33.0, 38.2; NS). Following the high-intensity exercise they chose a diet with 39.9% (95% CI: 37.2, 42.6) fat, which was 3.2% (95% CI: 0.6, 5.9) higher than following the low-intensity exercise (P<0.05) and 4.2% (95% CI: 1.1, 7.4) more than their habitual diet (P<0.01). The present study shows that changing the type of activity of a single exercise bout from 30% of maximal aerobic capacity for 60 min to 60% for only 30 min resulted in consumption of a diet the following day with a higher fat energy percentage compared with the diet selected after the low-intensity exercise. However, the higher fat content diet did not result in a higher energy intake.

  16. Muscle Activation During Exercise in Severe Acute Hypoxia: Role of Absolute and Relative Intensity

    Science.gov (United States)

    Torres-Peralta, Rafael; Losa-Reyna, José; González-Izal, Miriam; Perez-Suarez, Ismael; Calle-Herrero, Jaime; Izquierdo, Mikel

    2014-01-01

    Abstract Torres-Peralta, Rafael, José Losa-Reyna, Miriam González-Izal, Ismael Perez-Suarez, Jaime Calle-Herrero, Mikel Izquierdo, and José A.L. Calbet. Muscle activation during exercise in severe acute hypoxia: Role of absolute and relative intensity. High Alt Med Biol 15:472–482, 2014.—The aim of this study was to determine the influence of severe acute hypoxia on muscle activation during whole body dynamic exercise. Eleven young men performed four incremental cycle ergometer tests to exhaustion breathing normoxic (FIo2=0.21, two tests) or hypoxic gas (FIo2=0.108, two tests). Surface electromyography (EMG) activities of rectus femoris (RF), vastus medialis (VL), vastus lateralis (VL), and biceps femoris (BF) were recorded. The two normoxic and the two hypoxic tests were averaged to reduce EMG variability. Peak Vo2 was 34% lower in hypoxia than in normoxia (p<0.05). The EMG root mean square (RMS) increased with exercise intensity in all muscles (p<0.05), with greater effect in hypoxia than in normoxia in the RF and VM (p<0.05), and a similar trend in VL (p=0.10). At the same relative intensity, the RMS was greater in normoxia than in hypoxia in RF, VL, and BF (p<0.05), with a similar trend in VM (p=0.08). Median frequency increased with exercise intensity (p<0.05), and was higher in hypoxia than in normoxia in VL (p<0.05). Muscle contraction burst duration increased with exercise intensity in VM and VL (p<0.05), without clear effects of FIo2. No significant FIo2 effects on frequency domain indices were observed when compared at the same relative intensity. In conclusion, muscle activation during whole body exercise increases almost linearly with exercise intensity, following a muscle-specific pattern, which is adjusted depending on the FIo2 and the relative intensity of exercise. Both VL and VM are increasingly involved in power output generation with the increase of intensity and the reduction in FIo2. PMID:25225839

  17. Carbohydrate ingestion during prolonged high-intensity intermittent exercise: impact on affect and perceived exertion.

    Science.gov (United States)

    Backhouse, S H; Ali, A; Biddle, S J H; Williams, C

    2007-10-01

    This study was designed to determine the effects of ingesting a carbohydrate (CHO) solution on affective states and rating of perceived exertion (RPE) during prolonged intermittent high-intensity exercise. Seventeen male soccer players completed a prolonged intermittent high-intensity exercise protocol for 90 min on two occasions, separated by at least 7 days. Participants consumed either a 6.4% CHO (0.6 g/kg body mass (BM)/h) or an artificially sweetened placebo (PLA) solution immediately before (8 mL/kg BM) and every 15 min (3 mL/kg BM) during exercise in a double-blind, counterbalanced design. Pleasure-displeasure, perceived activation, RPE and plasma glucose concentration was assessed. The results showed that compared with the CHO trial, perceived activation were lower in the placebo trial during the last 30 min of exercise and this was accompanied by lowered plasma glucose concentrations. In the CHO trial, RPE was maintained in the last 30 min of exercise but carried on increasing in the PLA trial. Therefore, CHO ingestion during prolonged high-intensity exercise appears to elicit an enhanced perceived activation profile that may impact upon task persistence and performance. This finding is in addition to the physiological and metabolic benefits of the exogenous energy supply.

  18. High-intensity exercise attenuates postprandial lipaemia and markers of oxidative stress.

    Science.gov (United States)

    Gabriel, Brendan; Ratkevicius, Aivaras; Gray, Patrick; Frenneaux, Michael P; Gray, Stuart R

    2012-09-01

    Regular exercise can reduce the risk of CVD (cardiovascular disease). Although moderate-intensity exercise can attenuate postprandial TAG (triacylglycerol), high-intensity intermittent exercise might be a more effective method to improve health. We compared the effects of high-intensity intermittent exercise and 30 min of brisk walking on postprandial TAG, soluble adhesion molecules and markers of oxidative stress. Nine men each completed three 2-day trials. On day 1, subjects rested (control), walked briskly for 30 min (walking) or performed 5×30 s maximal sprints (high-intensity). On day 2, subjects consumed a high-fat meal for breakfast and 3 h later for lunch. Blood samples were taken at various times and analysed for TAG, glucose, insulin, ICAM-1 (intracellular adhesion molecule-1), VCAM-1 (vascular adhesion molecule-1), TBARS (thiobarbituric acid- reactive substances), protein carbonyls and β-hydroxybutyrate. On day 2 of the high-intensity trial, there was a lower (Pwalking trial (8.98±2.84 mmol/l per 7 h). A trend (P=0.056) for a reduced total TAG AUC was also seen during the high-intensity trial (14.13±2.83 mmol/l per 7 h) compared with control (17.18±3.92 mmol/l per 7 h), walking showed no difference (16.33±3.51 mmol/l per 7 h). On day 2 of the high-intensity trial plasma TBARS and protein carbonyls were also reduced (Pwalking trials. In conclusion, high-intensity intermittent exercise attenuates postprandial TAG and markers of oxidative stress after the consumption of a high-fat meal.

  19. Effect of moderate- and high-intensity acute exercise on appetite in obese individuals

    DEFF Research Database (Denmark)

    Martins, Catia; Stensvold, Dorthe; Finlayson, Graham

    2015-01-01

    /obese volunteers. Participants were assigned to the control, MICC, HIIC, and S-HIIC conditions, 1 wk apart, in a counterbalanced order. Exercise was performed 1 h after a standard breakfast. An ad libitum test lunch was served 3 h after breakfast. Fasting/postprandial plasma samples of insulin, acylated ghrelin......, hunger or fullness ratings, EI, or food reward. CONCLUSIONS: Our findings suggest that, in overweight/obese individuals, isocaloric bouts of moderate- or high-intensity exercise lead to a similar appetite response. This strengthens previous findings in normal-weight individuals that acute exercise, even...

  20. Lipid oxidation according to intensity and exercise duration in overweight men and women.

    Science.gov (United States)

    Pillard, Fabien; Moro, Cédric; Harant, Isabelle; Garrigue, Eric; Lafontan, Max; Berlan, Michel; Crampes, François; de Glisezinski, Isabelle; Rivière, Daniel

    2007-09-01

    Our objective was to compare the effect of different exercise intensities on lipid oxidation in overweight men and women. Nine young, healthy, overweight men and women were studied (age, 31.4 +/- 2.3 and 26.7 +/- 2.1 years; BMI, 27.9 +/- 0.4 and 27.2 +/- 0.5; for men and women, respectively). On one study day, the subjects first performed 30 minutes of cycling exercise at 30% of their maximal oxygen uptake (Vo(2max); E1 session), followed by 30 minutes of exercise at 50% Vo(2max) (E2 session). On a second study day, a similar E1 session was followed by 30 minutes of exercise at 70% Vo(2max) (E3 session). From the gas exchange measurements, the respiratory exchange ratio (RER) and the fat oxidation rate (FOR) were calculated. Plasma concentrations of glycerol and non-esterified fatty acids (NEFAs) were assayed. RER was significantly lower for women during only the E1 session. For both sexes, RER decreased over time during the E2 and E3 sessions. During the E1 session, the FOR per kilogram of lean mass (LM) was higher among women, and it did not change over time despite an increase in plasma NEFAs. FOR per kilogram of LM was higher during the E2 exercise for both sexes. During E2 and E3 sessions, as the exercise time was prolonged, the FOR/kg LM increased simultaneously with the increase in the plasma glycerol. Lipid oxidation during exercise is optimized for moderate and lengthy exercise. The enhancement of lipid oxidation occurring over time during moderate- and high-intensity exercises could be, in part, linked to the improvement of lipid mobilization. This fact is discussed to shed light on exercise modalities as a tool for the management of overweight.

  1. High-intensity interval exercise and cerebrovascular health: curiosity, cause, and consequence.

    Science.gov (United States)

    Lucas, Samuel J E; Cotter, James D; Brassard, Patrice; Bailey, Damian M

    2015-06-01

    Exercise is a uniquely effective and pluripotent medicine against several noncommunicable diseases of westernised lifestyles, including protection against neurodegenerative disorders. High-intensity interval exercise training (HIT) is emerging as an effective alternative to current health-related exercise guidelines. Compared with traditional moderate-intensity continuous exercise training, HIT confers equivalent if not indeed superior metabolic, cardiac, and systemic vascular adaptation. Consequently, HIT is being promoted as a more time-efficient and practical approach to optimize health thereby reducing the burden of disease associated with physical inactivity. However, no studies to date have examined the impact of HIT on the cerebrovasculature and corresponding implications for cognitive function. This review critiques the implications of HIT for cerebrovascular function, with a focus on the mechanisms and translational impact for patient health and well-being. It also introduces similarly novel interventions currently under investigation as alternative means of accelerating exercise-induced cerebrovascular adaptation. We highlight a need for studies of the mechanisms and thereby also the optimal dose-response strategies to guide exercise prescription, and for studies to explore alternative approaches to optimize exercise outcomes in brain-related health and disease prevention. From a clinical perspective, interventions that selectively target the aging brain have the potential to prevent stroke and associated neurovascular diseases.

  2. High-intensity interval exercise and cerebrovascular health: curiosity, cause, and consequence

    Science.gov (United States)

    Lucas, Samuel J E; Cotter, James D; Brassard, Patrice; Bailey, Damian M

    2015-01-01

    Exercise is a uniquely effective and pluripotent medicine against several noncommunicable diseases of westernised lifestyles, including protection against neurodegenerative disorders. High-intensity interval exercise training (HIT) is emerging as an effective alternative to current health-related exercise guidelines. Compared with traditional moderate-intensity continuous exercise training, HIT confers equivalent if not indeed superior metabolic, cardiac, and systemic vascular adaptation. Consequently, HIT is being promoted as a more time-efficient and practical approach to optimize health thereby reducing the burden of disease associated with physical inactivity. However, no studies to date have examined the impact of HIT on the cerebrovasculature and corresponding implications for cognitive function. This review critiques the implications of HIT for cerebrovascular function, with a focus on the mechanisms and translational impact for patient health and well-being. It also introduces similarly novel interventions currently under investigation as alternative means of accelerating exercise-induced cerebrovascular adaptation. We highlight a need for studies of the mechanisms and thereby also the optimal dose-response strategies to guide exercise prescription, and for studies to explore alternative approaches to optimize exercise outcomes in brain-related health and disease prevention. From a clinical perspective, interventions that selectively target the aging brain have the potential to prevent stroke and associated neurovascular diseases. PMID:25833341

  3. Similar Anti-Inflammatory Acute Responses from Moderate-Intensity Continuous and High-Intensity Intermittent Exercise.

    Science.gov (United States)

    Cabral-Santos, Carolina; Gerosa-Neto, José; Inoue, Daniela Sayuri; Panissa, Valéria Leme Gonçalves; Gobbo, Luís Alberto; Zagatto, Alessandro Moura; Campos, Eduardo Zapaterra; Lira, Fábio Santos

    2015-12-01

    The purpose of this study was to compare the effect of high-intensity intermittent exercise (HIIE) versus volume matched steady state exercise (SSE) on inflammatory and metabolic responses. Eight physically active male subjects completed two experimental sessions, a 5-km run on a treadmill either continuously (70% vVO2max) or intermittently (1:1 min at vVO2max). Blood samples were collected at rest, immediately, 30 and 60 minutes after the exercise session. Blood was analyzed for glucose, non-ester fatty acid (NEFA), uric acid, lactate, cortisol, and cytokines (IL-6, IL-10 and TNF-α) levels. The lactate levels exhibited higher values immediately post-exercise than at rest (HIIE 1.34 ± 0.24 to 7.11 ± 2.85, and SSE 1.35 ± 0.14 to 4.06±1.60 mmol·L(-1), p 0.05). Cortisol, IL-6, IL-10 and TNF-α levels showed time-dependent changes under the different conditions (p < 0.05), however, the area under the curve of TNF-α in the SSE were higher than HIIE (p < 0.05), and the area under the curve of IL-6 in the HIIE showed higher values than SSE (p < 0.05). In addition, both exercise conditions promote increased IL-10 levels and IL-10/TNF-α ratio (p < 0.05). In conclusion, our results demonstrated that both exercise protocols, when volume is matched, promote similar inflammatory responses, leading to an anti-inflammatory status; however, the metabolic responses are different. Key pointsMetabolic contribution of both exercise, HIIE and SSE, was different.Both protocols leading to an anti-inflammatory status.HIIE induce a higher energy expenditure take into account total session duration.

  4. Limitations in intense exercise performance of athletes - effect of speed endurance training on ion handling and fatigue development

    DEFF Research Database (Denmark)

    Hostrup, Morten; Bangsbo, Jens

    2017-01-01

    Mechanisms underlying fatigue development and limitations for performance during intense exercise have been intensively studied during the past couple of decades. Fatigue development may involve several interacting factors and depends on type of exercise undertaken and training level...... into the beneficial effects of SET have been conducted in untrained and recreationally active individuals, making extrapolation towards athletes' performance difficult. Nevertheless, recent studies indicate that only few weeks of SET enhances intense exercise performance in highly-trained individuals...

  5. Effect of moderate or high intensity exercise on hypothyroid rats exposed to acute stress.

    Science.gov (United States)

    Kasimay Çakir, Özgür; Özbeyli, Dilek; Şenel, Ebru; Contuk, Gazi; Velioğlu Öğünç, Ayliz; Çetinel, Şule; Yeğen, Berrak Ç

    2017-12-01

    There are contradictory results about stress response in hypothyroidism and in exercising with variant intensities. We aimed to investigate the potential anxiolytic and protective effects of different intensities of exercise on acute psychological stress in hypothyroidism. Rats (N.=48) were divided as sedentary, moderate intensity (MIE) and high intensity exercise (HIE) groups. Rats were administered intraperitoneally with 6-n-propyl-2-thiouracil (PTU, 10 mg/kg) for 15 days to induce hypothyroidism. Starting by the 3rd week, treadmill exercise was performed moderately (30 min/day) or at high intensity (60 min/day) for 6 weeks, 5 days/week. At the end of the 8th week, exposure to water avoidance stress was used for induction of acute stress. Anxiety-like behavior was determined by holeboard test before and after stress inductions. Serum IL-1β and IL-6 assays, and myeloperoxidase activity (MPO), malondialdehyde (MDA), and glutathione (GSH) measurements, and histological analysis of heart, liver, stomach and small intestine were made. All groups showed increased anxiety-like behavior following acute stress induction. After acute stress induction, increased MPO and MDA levels in heart and elevated MPO activity in liver were inhibited in PTU-treated HIE group. In MIE rats, increased MPO and declined GSH levels of the gastric tissue and small intestine, and elevated MDA levels of gastric tissue were reversed in PTU-treated MIE group. Major histological changes that occurred by both intensities of exercise under stress condition were improved by PTU. Our results indicate that hypothyroid state may be protective against stress- and exhaustive exercise-induced oxidative damage.

  6. Serum cardiac troponin I analysis to determine the excessiveness of exercise intensity: A novel equation.

    Science.gov (United States)

    Voets, Philip J G M; Maas, Roderick P P W M

    2016-03-07

    Physical exertion is often promoted because of its beneficial health effects. This only holds true, however, as long as the optimal exercise intensity is not exceeded. If physical exertion becomes too strenuous or prolonged, cardiac injury or dysfunction may occur. Consequently, a significant elevation of the serum concentration of the sensitive and specific cardiac biomarker troponin I can be observed. In this article, we present the derivation of a novel equation that can be used to evaluate to what extent the intensity of conducted endurance exercise was excessive, based on a post-exercise assessment of serum cardiac troponin I. This is convenient, as exercise intensity is difficult for an athlete to quantify accurately and the currently used heart rate indices can be affected by various physiological and environmental factors. Serum cardiac troponin I, on the other hand, is a post-hoc parameter that directly reflects the actual effects on the myocardium and may therefore be a promising alternative. To our knowledge, this is the first method to determine relative exercise intensity in retrospect. We therefore believe that this equation can serve as a potentially valuable tool to objectively evaluate the benefits or harmful effects of physical exertion. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Tolerance to exercise intensity modulates pleasure when exercising in music: The upsides of acoustic energy for High Tolerant individuals

    OpenAIRE

    Carlier, Mauraine; Delevoye-Turrell, Yvonne

    2017-01-01

    Moderate physical activity can be experienced by some as pleasurable and by others as discouraging. This may be why many people lack sufficient motivation to participate in the recommended 150 minutes of moderately intense exercise per week. In the present study, we assessed how pleasure and enjoyment were modulated differently by one?s tolerance to self-paced physical activity. Sixty-three healthy individuals were allocated to three independent experimental conditions: a resting condition (w...

  8. Analog Exercise Hardware to Implement a High Intensity Exercise Program During Bed Rest

    Science.gov (United States)

    Loerch, Linda; Newby, Nate; Ploutz-Snyder, Lori

    2012-01-01

    Background: In order to evaluate novel countermeasure protocols in a space flight analog prior to validation on the International Space Station (ISS), NASA's Human Research Program (HRP) is sponsoring a multi-investigator bedrest campaign that utilizes a combination of commercial and custom-made exercise training hardware to conduct daily resistive and aerobic exercise protocols. This paper will describe these pieces of hardware and how they are used to support current bedrest studies at NASA's Flight Analog Research Unit in Galveston, TX. Discussion: To implement candidate exercise countermeasure studies during extended bed rest studies the following analog hardware are being utilized: Stand alone Zero-Gravity Locomotion Simulator (sZLS) -- a custom built device by NASA, the sZLS allows bedrest subjects to remain supine as they run on a vertically-oriented treadmill (0-15 miles/hour). The treadmill includes a pneumatic subject loading device to provide variable body loading (0-100%) and a harness to keep the subject in contact with the motorized treadmill to provide a ground reaction force at their feet that is quantified by a Kistler Force Plate. Supine Cycle Ergometer -- a commercially available supine cycle ergometer (Lode, Groningen, Netherlands) is used for all cycle ergometer sessions. The ergometer has adjustable shoulder supports and handgrips to help stabilize the subject during exercise. Horizontal Squat Device (HSD) -- a custom built device by Quantum Fitness Corp (Stafford, TX), the HSD allows for squat exercises to be performed while lying in a supine position. The HSD can provide 0 to 600 pounds of force in selectable 5 lb increments, and allows hip translation in both the vertical and horizontal planes. Prone Leg Curl -- a commercially available prone leg curl machine (Cybex International Inc., Medway, MA) is used to complete leg curl exercises. Horizontal Leg Press -- a commercially available horizontal leg press (Quantum Fitness Corporation) is

  9. EFFECT OF EXERCISE TRAINING OF DIFFERENT INTENSITIES ON ANTI-INFLAMMATORY REACTION IN STREPTOZOTOCIN-INDUCED DIABETIC RATS

    Directory of Open Access Journals (Sweden)

    J.–S. Kim

    2014-07-01

    Full Text Available The study investigated the effect of high- and low-intensity exercise training on inflammatory reaction of blood and skeletal muscle in streptozotocin (STZ-induced diabetic male Sprague-Dawley rats (243 ± 7 g, 8 weeks. The rats completed treadmill running in either high-intensity exercise (6 weeks of exercise training, acute bouts of exercise or low-intensity exercise (6 weeks of exercise training. Non-running, sedentary rats served as controls. To induce diabetes mellitus, rats received a peritoneal injection of STZ (50 mg · kg-1. Rats were sacrificed immediately after an acute bout of exercise and 6 weeks of exercise training. Inflammatory factors were analyzed by ELISA and by immune blotting from the soleus and extensor digitorum longus muscles. In the serum, inflammatory cytokines (IL-1β, TNF-α, IL-6, IL-4 and reactive oxygen species (ROS (nitric oxide and malondialdehyde increased in diabetic rats. However, all exercise training groups displayed reduced inflammatory cytokines and reactive oxygen species. In skeletal muscles, low-intensity exercise training, but not high intensity exercise, reduced the levels of COX-2, iNOS, and MMP-2, which were otherwise markedly elevated in the presence of STZ. Moreover, the levels of GLUT-4 and MyoD were effectively increased by different exercise intensity and exercise duration. Low-intensity exercise training appeared most effective to reduce diabetes-related inflammation. However, high-intensity training also reduced inflammatory factors in tissue-specific muscles. The data implicate regular exercise in protecting against chronic inflammatory diseases, such as diabetes.

  10. Exercise Intensity and Incidence of Metabolic Syndrome: The SUN Project.

    Science.gov (United States)

    Hidalgo-Santamaria, María; Fernandez-Montero, Alejandro; Martinez-Gonzalez, Miguel A; Moreno-Galarraga, Laura; Sanchez-Villegas, Almudena; Barrio-Lopez, María T; Bes-Rastrollo, Maira

    2017-04-01

    Emerging evidence suggests that vigorous physical activity may be associated with higher cardioprotective benefits than moderate physical activity. This study aimed to assess the long-term relationship between the intensity of leisure time physical activity (LTPA) and the risk of developing metabolic syndrome (MS) in a prospective cohort study. The Seguimiento Universidad de Navarra (SUN) Project comprises Spanish university graduates. Participants (n=10,145) initially free of MS were followed for a minimum of 6 years (2008-2014). Analysis was conducted in 2015. Physical activity was assessed though a validated questionnaire. The intensity of each physical activity was measured in METs. The intensity of LTPA was estimated by the ratio between total METs/week and total hours of LTPA/week, obtaining the mean METs/hour of LTPA. MS was defined according to the harmonizing definition. The association between the intensity of LTPA (METs/hour) and MS was assessed with logistic regression models adjusting for potential confounders. Among 10,145 participants initially free of any MS criteria, 412 new MS cases were observed. Vigorous LTPA was associated with a 37% relatively lower risk (AOR=0.63, 95% CI=0.44, 0.89) compared with light LTPA. For a given total energy expenditure, independent of the time spent on it, participants who performed vigorous LTPA exhibited a higher reduction in the risk of MS than those who performed light to moderate LTPA. Vigorous LTPA was significantly associated with lower risk of developing MS after a 6-year follow-up period. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Relationship between performance at different exercise intensities and skeletal muscle characteristics

    DEFF Research Database (Denmark)

    Iaia, F Marcello; Perez-Gomez, Jorge; Thomassen, Martin

    2011-01-01

    The hypothesis investigated whether exercise performance over a broad range of intensities is determined by specific skeletal muscle characteristics. Seven subjects performed 8-10 exhaustive cycle trials at different work loads ranging from 150 to 700 W (150 min - 20 s). No relationships between ...... the performance times at high and low work loads were observed. A relationship (P......The hypothesis investigated whether exercise performance over a broad range of intensities is determined by specific skeletal muscle characteristics. Seven subjects performed 8-10 exhaustive cycle trials at different work loads ranging from 150 to 700 W (150 min - 20 s). No relationships between...

  12. 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.

  13. Acute effects of moderate intensity aerobic exercise on affective withdrawal symptoms and cravings among women smokers.

    Science.gov (United States)

    Williams, David M; Dunsiger, Shira; Whiteley, Jessica A; Ussher, Michael H; Ciccolo, Joseph T; Jennings, Ernestine G

    2011-08-01

    A growing number of laboratory studies have shown that acute bouts of aerobic exercise favorably impact affect and cravings among smokers. However, randomized trials have generally shown exercise to have no favorable effect on smoking cessation or withdrawal symptoms during quit attempts. The purpose of the present study was to explore this apparent contradiction by assessing acute changes in affect and cravings immediately prior to and following each exercise and contact control session during an eight-week smoking cessation trial. Sixty previously low-active, healthy, female smokers were randomized to an eight-week program consisting of brief baseline smoking cessation counseling and the nicotine patch plus either three sessions/week of moderate intensity aerobic exercise or contact control. Findings revealed a favorable impact of exercise on acute changes in positive activated affect (i.e., energy), negative deactivated affect (i.e., tiredness), and cigarette cravings relative to contact control. However, effects dissipated from session to session. Results suggest that aerobic exercise has potential as a smoking cessation treatment, but that it must be engaged in frequently and consistently over time in order to derive benefits. Thus, it is not surprising that previous randomized controlled trials-in which adherence to exercise programs has generally been poor-have been unsuccessful in showing effects of aerobic exercise on smoking cessation outcomes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. The Metabolic Cost of a High Intensity Exercise Program During Bed Rest

    Science.gov (United States)

    Hackney, Kyle; Everett, Meghan; Guined, Jamie; Cunningham, Daid

    2012-01-01

    Background: Given that disuse-related skeletal muscle atrophy may be exacerbated by an imbalance between energy intake and output, the amount of energy required to complete exercise countermeasures is an important consideration in the well being of subject health during bed rest and spaceflight. Objective: To evaluate the energy cost of a high intensity exercise program performed during short duration bed rest. Methods: 9 subjects (8 male and 1 female; 34.5 +/- 8.2 years) underwent 14 days of bed rest and exercise countermeasures. Exercise energy expenditure and excess post exercise oxygen consumption (EPOC) were collected once in each of 5 different exercise protocols (30 second, 2 minute and 4 minute intervals, continuous aerobic and a variety of resistance exercises) during bed rest. Body mass, basal metabolic rate (BMR), upper and lower leg muscle, subcutaneous, and intramuscular adipose tissue (IMAT) volumes were assessed before and at the end of bed rest. Results: There were no significant differences in body mass (pre: 75.1 +/- 10.5 kg; post: 75.2 +/- 10.1 kg), BMR (pre: 1649 +/- 216 kcal; post: 1657 +/- 177 kcal), muscle subcutaneous, or IMAT volumes (Table 2) after 14 days of bed rest and exercise. Body mass was maintained with an average daily intake of 2710 +/- 262 kcal (36.2 +/- 2.1 kcal/kg/day), while average daily energy expenditure was 2579 +/-311 kcal (34.5 +/- 3.6 kcal/kg/day). Exercise energy expenditure was significantly greater as a result of continuous aerobic exercise than all other exercise protocols.

  15. RELATIONSHIP BETWEEN BLOOD LACTATE AND HYPERVENTILATION DURING HIGH-INTENSITY CONSTANT-LOAD EXERCISE IN HEAT

    Directory of Open Access Journals (Sweden)

    T. Chiba

    2011-09-01

    Full Text Available The purpose of this study was to examine the relationship between hyperventilation and increase in blood lactate during high-intensity constant-load exercise in heat and normal conditions. Seven male volunteers exercised for 10 min on a cycle ergometer at 80%·VO2max in heat (40ºC, 50%relative humidity: HT and normal conditions (20ºC, 50% relative humidity: CON. Oxygen uptake, carbon dioxide output, ventilation, blood lactate and blood electrolytes (K , Na , Cl− were measured in HT and CON. We found that ventilation was significantly higher during exercise in HT compared with CON (p<0.05 and RER tends to be higher in HT than in CON. Blood lactate was significantly higher at 3 min during exercise in HT compared with CON (5.96 ± 0.57 mEq·l-1 5.00 ± 0.28 mEq·l-1, p<0.05. Change in strong ion difference [∆SID = (∆K ∆Na − (∆Cl− ∆La−], which affects ∆HCO3− in blood significantly, was lower at 5 min during exercise in HT compared with in CON (p<0.05. These results suggest that hyperventilation during exercise in heat would induce lower HCO3− in blood and consequently would result in an increase in blood lactate at an earlier time during high-intensity exercise in heat. It was concluded that hyperventilation during short-term high-intensity exercise in heat is temporarily associated with an increase in blood lactate.

  16. Is there spontaneous energy expenditure compensation in response to intensive exercise in obese youth?

    Science.gov (United States)

    Thivel, D; Aucouturier, J; Metz, L; Morio, B; Duché, P

    2014-04-01

    Physical activity is mainly used in weight control strategies to favour energy expenditure. Some evidence suggests that exercise might not have the expected impact on energy balance, and may actually cause a decrease in the subsequent physical activity energy expenditure. To question the impact of an acute exercise session of varying intensities on daily energy expenditure in lean and obese adolescents. Data from three separate studies conducted in lean and obese 12-15 years old adolescents (study 1: 12 obese; study 2: 10 obese and nine lean; study 3: 15 obese) have been used. Daily energy expenditure (DEE) was assessed in studies 1 and 2 during an exercise condition with an exercise bout at 70%VO(2max) (EX) and a rest day (REST) (using Actiheart and Armbands, respectively). In study 3, DEE was assessed in calorimetric chambers during (i) a high intensity exercise condition (HIE - 75%VO(2max)) and (ji) a condition with a low intensity exercise (LIE - 40%VO(2max)) and (iii) a rest condition (REST). Morning energy expenditure was significantly higher during the exercise conditions whatever the intensity compared with rest. Afternoon energy expenditure was significantly lower following HIE compared to the rest condition in studies 2 and 3. Afternoon energy expenditure was not significantly different between LIE and REST in study 2. Total DEE was not significantly different between conditions in the three studies. Obese adolescents seem to show a compensatory response to an acute session of HIE (>70%VO(2max)) by decreasing their following physical activity energy expenditure. Although HIE favours body composition, physical fitness and metabolic profile improvements, this induced compensatory energy expenditure response has to be considered to optimize its effect on weight loss. © 2013 The Authors. Pediatric Obesity © 2013 International Association for the Study of Obesity.

  17. Differential effects of exercise intensities in hippocampal BDNF, inflammatory cytokines and cell proliferation in rats during the postnatal brain development.

    Science.gov (United States)

    de Almeida, Alexandre Aparecido; Gomes da Silva, Sérgio; Fernandes, Jansen; Peixinho-Pena, Luiz Fernando; Scorza, Fulvio Alexandre; Cavalheiro, Esper Abrão; Arida, Ricardo Mario

    2013-10-11

    It has been established that low intensities of exercise produce beneficial effects for the brain, while high intensities can cause some neuronal damage (e.g. exacerbated inflammatory response and cell death). Although these effects are documented in the mature brain, the influence of exercise intensities in the developing brain has been poorly explored. To investigate the impact of exercise intensity in developing rats, we evaluated the hippocampal level of brain derived neurotrophic factor (BDNF), inflammatory cytokines (TNFα, IL6 and IL10) and the occurrence of hippocampal cell degeneration and proliferation at different stages of postnatal brain development of rats submitted to two physical exercise intensities. To this point, male rats were divided into different age groups: P21, P31, P41 and P51. Each age group was submitted to two exercise intensities (low and high) on a treadmill over 10 consecutive days, except the control rats. We verified that the density of proliferating cells was significantly higher in the dentate gyrus of rats submitted to low-intensity exercise from P21 to P30 compared with high-intensity exercise and control rats. A significant increase of proliferative cell density was found in rats submitted to high-intensity exercise from P31 to P40 when compared to low-intensity exercise and control rats. Elevated hippocampal levels of IL6 were detected in rats submitted to high-intensity exercise from P21 to P30 compared to control rats. From P41 to P50 period, higher levels of BDNF, TNFα and IL10 were found in the hippocampal formation of rats submitted to high-intensity exercise in relation to their control rats. Our data show that exercise-induced neuroplastic effects on BDNF levels and cellular proliferation in the hippocampal region are dependent on exercise intensity and developmental period. Thus, exercise intensity is an inflammation-inducing factor and exercise-induced inflammatory response during the postnatal brain development is

  18. 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.

  19. Acute effect of exercise intensity and duration on acylated ghrelin and hunger in men.

    Science.gov (United States)

    Broom, David R; Miyashita, Masashi; Wasse, Lucy K; Pulsford, Richard; King, James A; Thackray, Alice E; Stensel, David J

    2017-03-01

    Acute exercise transiently suppresses the orexigenic gut hormone acylated ghrelin, but the extent to which exercise intensity and duration determine this response is not fully understood. The effects of manipulating exercise intensity and duration on acylated ghrelin concentrations and hunger were examined in two experiments. In experiment one, nine healthy males completed three, 4-h conditions (control, moderate-intensity running (MOD) and vigorous-intensity running (VIG)), with an energy expenditure of ~2.5 MJ induced in both MOD (55-min running at 52% peak oxygen uptake (V.O2peak)) and VIG (36-min running at 75% V.O2peak). In experiment two, nine healthy males completed three, 9-h conditions (control, 45-min running (EX45) and 90-min running (EX90)). Exercise was performed at 70% V.O2peak In both experiments, participants consumed standardised meals, and acylated ghrelin concentrations and hunger were quantified at predetermined intervals. In experiment one, delta acylated ghrelin concentrations were lower than control in MOD (ES = 0.44, P = 0.01) and VIG (ES = 0.98, P Hunger ratings were similar across the conditions (P = 0.35). In experiment two, delta acylated ghrelin concentrations were lower than control in EX45 (ES = 0.77, P Hunger ratings were lower than control in EX45 (ES = 0.20, P = 0.01) and EX90 (ES = 0.27, P = 0.001); EX45 and EX90 were similar (ES = 0.07, P = 0.34). Hunger and delta acylated ghrelin concentrations remained suppressed at 1.5 h in EX90 but not EX45. In conclusion, exercise intensity, and to a lesser extent duration, are determinants of the acylated ghrelin response to acute exercise. © 2017 Society for Endocrinology.

  20. Effects of leg massage on recovery from high intensity cycling exercise

    Science.gov (United States)

    Robertson, A; Watt, J; Galloway, S

    2004-01-01

    Background: The effect of massage on recovery from high intensity exercise is debatable. Many studies on massage suffer from methodological flaws such as poor standardisation of previous exercise, lack of dietary control, and inappropriate massage duration. Objective: To examine the effects of leg massage compared with passive recovery on lactate clearance, muscular power output, and fatigue characteristics after repeated high intensity cycling exercise, with the conditions before the intervention controlled and standardised. Methods: Nine male games players participated. They attended the laboratory on two occasions one week apart and at the same time of day. Dietary intake and activity were replicated for the two preceding days on each occasion. After baseline measurement of heart rate and blood lactate concentration, subjects performed a standardised warm up on the cycle ergometer. This was followed by six standardised 30 second high intensity exercise bouts, interspersed with 30 seconds of active recovery. After five minutes of active recovery and either 20 minutes of leg massage or supine passive rest, subjects performed a second standardised warm up and a 30 second Wingate test. Capillary blood samples were drawn at intervals, and heart rate, peak power, mean power, and fatigue index were recorded. Results: There were no significant differences in mean power during the initial high intensity exercise bouts (p = 0.92). No main effect of massage was observed on blood lactate concentration between trials (p = 0.82) or heart rate (p = 0.81). There was no difference in the maximum power (p = 0.75) or mean power (p = 0.66) in the subsequent Wingate test, but a significantly lower fatigue index was observed in the massage trial (p = 0.04; mean (SD) fatigue index 30.2 (4.1)% v 34.2 (3.3)%). Conclusions: No measurable physiological effects of leg massage compared with passive recovery were observed on recovery from high intensity exercise, but the subsequent effect on

  1. Similar Anti-Inflammatory Acute Responses from Moderate-Intensity Continuous and High-Intensity Intermittent Exercise

    Directory of Open Access Journals (Sweden)

    Carolina Cabral-Santos, José Gerosa-Neto, Daniela Sayuri Inoue, Valéria Leme Gonçalves Panissa, Luís Alberto Gobbo, Alessandro Moura Zagatto, Eduardo Zapaterra Campos, Fábio Santos Lira

    2015-12-01

    Full Text Available The purpose of this study was to compare the effect of high-intensity intermittent exercise (HIIE versus volume matched steady state exercise (SSE on inflammatory and metabolic responses. Eight physically active male subjects completed two experimental sessions, a 5-km run on a treadmill either continuously (70% vVO2max or intermittently (1:1 min at vVO2max. Blood samples were collected at rest, immediately, 30 and 60 minutes after the exercise session. Blood was analyzed for glucose, non-ester fatty acid (NEFA, uric acid, lactate, cortisol, and cytokines (IL-6, IL-10 and TNF-α levels. The lactate levels exhibited higher values immediately post-exercise than at rest (HIIE 1.34 ± 0.24 to 7.11 ± 2.85, and SSE 1.35 ± 0.14 to 4.06±1.60 mmol·L-1, p 0.05. Cortisol, IL-6, IL-10 and TNF-α levels showed time-dependent changes under the different conditions (p < 0.05, however, the area under the curve of TNF-α in the SSE were higher than HIIE (p < 0.05, and the area under the curve of IL-6 in the HIIE showed higher values than SSE (p < 0.05. In addition, both exercise conditions promote increased IL-10 levels and IL-10/TNF-α ratio (p < 0.05. In conclusion, our results demonstrated that both exercise protocols, when volume is matched, promote similar inflammatory responses, leading to an anti-inflammatory status; however, the metabolic responses are different.

  2. The effect of low and moderate intensity aerobic exercises on sleep quality in men older adults.

    Science.gov (United States)

    Akbari Kamrani, Ahmad Ali; Shams, Amir; Shamsipour Dehkordi, Parvaneh; Mohajeri, Robabeh

    2014-03-01

    Sleep is an active and complex rhythmic state that may be affected by the aging process. The purpose of present research was to investigate the effect of low and moderate intensity aerobic exercises on sleep quality in older adults. The research method is quasi-experimental with pre-test and post-test design. The statistical sample included 45 volunteer elderly men with age range of 60-70 years-old that divided randomly in two experimental groups (aerobic exercise with low and moderate intensity) and one control group. In each group selected 15 older adults based on inclusion and exclusion criteria (such as, without sleep apnea, not smoking, and no taking hypnotic drugs). First, all subjects were evaluated by a doctor to confirm their physical and mental health. Also, the maximum heart rate (MaxHR) of subjects was obtained by subtracting one's age from 220. Furthermore, based on aerobic exercise type (40-50% MaxHR for low intensity group and 60-70% MaxHR for moderate intensity group) the target MaxHR was calculated for each subject. The exercise protocol consisted of 8 weeks aerobic exercises (2 sessions in per-week) based on Rockport one-mile walking/running test and the control group continued their daily activities. All subjects in per-test and post-test stages completed the Petersburg Sleep Quality Index (PSQI). In pre-test stage, results showed that there were no significant differences between control and experimental groups in sleep quality and its components (P>0.05). On the other hand, results in post-test stage showed that there were significant differences between control and experimental groups in these variables (P<0.05). Also, the Tukey Post Hoc showed that the moderate intensity group scores in total sleep quality and its components were better than other groups (P<0.05). Finally, the low intensity group scores in total sleep quality and its components were better than control group (P<0.05). Generally, the present research showed that the aerobic

  3. The Effect of Structured Exercise Intervention on Intensity and Volume of Total Physical Activity

    Directory of Open Access Journals (Sweden)

    Niko Wasenius

    2014-12-01

    Full Text Available This study aimed to investigate the effects of a 12-week structured exercise intervention on total physical activity and its subcategories. Twenty-three overweight or obese middle aged men with impaired glucose regulation were randomized into a 12-week Nordic walking group, a power-type resistance training group, and a non-exercise control group. Physical activity was measured with questionnaires before the intervention (1–4 weeks and during the intervention (1–12 weeks and was expressed in metabolic equivalents of task. No significant change in the volume of total physical activity between or within the groups was observed (p > 0.050. The volume of total leisure-time physical activity (structured exercises + non-structured leisure-time physical activity increased significantly in the Nordic walking group (p 0.050 compared to the control group. In both exercise groups increase in the weekly volume of total leisure-time physical activity was inversely associated with the volume of non-leisure-time physical activities. In conclusion, structured exercise intervention did not increase the volume of total physical activity. Albeit, endurance training can increase the volume of high intensity physical activities, however it is associated with compensatory decrease in lower intensity physical activities. To achieve effective personalized exercise program, individuality in compensatory behavior should be recognised.

  4. Combined effect of coffee ingestion and repeated bouts of low-intensity exercise on fat oxidation.

    Science.gov (United States)

    Kurobe, Kazumichi; Nakao, Saori; Nishiwaki, Masato; Matsumoto, Naoyuki

    2017-03-01

    We investigated the effect of the combination of coffee ingestion and repeated bouts of low-intensity exercise on fat oxidation. Subjects were seven young, healthy male adults. They performed four trials: a single 30-min bout of exercise following ingestion of plain hot water (WS) or coffee (CS); a trial with three 10-min bouts of exercise separated by 10-min periods of rest following ingestion of plain hot water (WR) or coffee (CR). The coffee contained 5 mg kg-1 of caffeine. All trials were performed on a cycle ergometer at 40% maximal oxygen uptake for each subject an hour after beverage ingestion. Oxygen uptake in the CS and CR trials was higher compared with the WS and WR trials at 90 min after exercise (Pcoffee intake and repeated bouts of low-intensity exercise enhances fat oxidation in the period after exercise. © 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  5. Acute effect of resistance exercise performed at different intensities on the hemodynamics of normotensive men

    Directory of Open Access Journals (Sweden)

    Mauricio Assis Saldanha

    2016-06-01

    Full Text Available The aim of this study was to investigate the acute effect of resistance exercise performed at different intensities on the hemodynamics of normotensive men. The study included 10 normotensive and recreationally-trained men (25.40 ± 6.90 years performed the following three experimental protocols in a randomized order: a 60% of 8RM; b 80% of 8RM; c 100% of 8RM. All protocols performed six exercises (Leg Press, Vertical Bench Press, Leg Flexion, Close-Grip Seated Row, Leg Extension and Shoulder Press with three sets of eight repetitions for each exercise. Systolic blood pressure (SBP, diastolic blood pressure (DBP, heart rate (HR and double product (DP were measured at rest, at the end of exercise and during the 60-minute post-exercise. The findings showed that there was a significant reduction in the faster SBP with a longer duration (p 0.05. There were significantly higher elevations in HR and DP for 100% of 8RM at all times (p<0.0001. We conclude that high intensities (100% of 8RM promote post-exercise hypotension with faster responses and greater duration and increase HR and DP in normotensive men.

  6. Enjoyment for High-Intensity Interval Exercise Increases during the First Six Weeks of Training: Implications for Promoting Exercise Adherence in Sedentary Adults.

    Science.gov (United States)

    Heisz, Jennifer J; Tejada, Mary Grace M; Paolucci, Emily M; Muir, Cameron

    2016-01-01

    This is the first study to show that enjoyment for high-intensity interval exercise increases with chronic training. Prior acute studies typically report high-intensity interval training (HIT) as being more enjoyable than moderate continuous training (MCT) unless the high-intensity intervals are too strenuous or difficult to complete. It follows that exercise competency may be a critical factor contributing to the enjoyment of HIT, and therefore building competency through chronic training may be one way to increase its enjoyment. To test this, we randomly assigned sedentary young adults to six weeks of HIT or MCT, and tracked changes in their enjoyment for the exercise. Enjoyment for HIT increased with training whereas enjoyment for MCT remained constant and lower. Changes in exercise enjoyment were predicted by increases in workload, suggesting that strength adaptions may be important for promoting exercise enjoyment. The results point to HIT as a promising protocol for promoting exercise enjoyment and adherence in sedentary young adults.

  7. The impact of brief high-intensity exercise on blood glucose levels

    Directory of Open Access Journals (Sweden)

    Adams OP

    2013-02-01

    Full Text Available O Peter AdamsFaculty of Medical Sciences, the University of the West Indies, Cave Hill Campus, St Michael, BarbadosBackground: Moderate-intensity exercise improves blood glucose (BG, but most people fail to achieve the required exercise volume. High-intensity exercise (HIE protocols vary. Maximal cycle ergometer sprint interval training typically requires only 2.5 minutes of HIE and a total training time commitment (including rest and warm up of 25 minutes per session. The effect of brief high-intensity exercise on blood glucose levels of people with and without diabetes is reviewed.Methods: HIE (≥80% maximal oxygen uptake, VO2max studies with ≤15 minutes HIE per session were reviewed.Results: Six studies of nondiabetics (51 males, 14 females requiring 7.5 to 20 minutes/week of HIE are reviewed. Two weeks of sprint interval training increased insulin sensitivity up to 3 days postintervention. Twelve weeks near maximal interval running (total exercise time 40 minutes/week improved BG to a similar extent as running at 65% VO2max for 150 minutes/week. Eight studies of diabetics (41 type 1 and 22 type 2 subjects were reviewed. Six were of a single exercise session with 44 seconds to 13 minutes of HIE, and the others were 2 and 7 weeks duration with 20 and 2 minutes/week HIE, respectively. With type 1 and 2 diabetes, BG was generally higher during and up to 2 hours after HIE compared to controls. With type 1 diabetics, BG decreased from midnight to 6 AM following HIE the previous morning. With type 2 diabetes, a single session improved postprandial BG for 24 hours, while a 2-week program reduced the average BG by 13% at 48 to 72 hours after exercise and also increased GLUT4 by 369%.Conclusion: Very brief HIE improves BG 1 to 3 days postexercise in both diabetics and nondiabetics. HIE is unlikely to cause hypoglycemia during and immediately after exercise. Larger and longer randomized studies are needed to determine the safety, acceptability, long

  8. Matching energy intake to expenditure of isocaloric exercise at high- and moderate-intensities.

    Science.gov (United States)

    Holliday, Adrian; Blannin, Andrew K

    2014-05-10

    Those seeking to manage their bodyweight use a variety of strategies, but the most common approaches involve attempting to exercise more and/or consume fewer calories. A poor comprehension of the energy cost of exercise and the energy content of food may contribute to weight-gain and the poor success rate of exercise weight-loss interventions. The purpose of this study is to investigate individuals' ability to consciously match energy intake with energy expenditure after isocaloric exercise at moderate and high intensities. In a counterbalanced cross-over study design, 14 low- to moderately-active, lean individuals (7 male, 7 female; mean age 23±3 years; mean BMI 22.0±3.2 kg·m(-2)) completed both a moderate-intensity (60% VO2max, MOD) and a high-intensity (90% VO2max, HIGH) exercise bout on a treadmill, matched for energy expenditure, EE (450 kcal). Participants were blinded to the intensity and duration of each bout. Thirty minutes post-exercise, participants were presented with a buffet, where they were asked to consume food in an attempt to match energy intake with the energy expended during the exercise bout. This was termed the "matching task," providing a matching task energy intake value (EI(MATCH)). Upon finishing the matching task, a verbal estimate of energy expenditure (EST) was obtained before the participant was allowed to return to the buffet to consume any more food, if desired. This intake was covertly measured and added to EI(MATCH) to obtain an ad libitum intake value (EI(AD LIB)). A significant condition × task interaction showed that, in MOD, EST was significantly lower than EE (298±156 kcal vs. 443±22 kcal, p=0.01). In the HIGH condition, EE, EI(MATCH) and EST were similar. In both conditions, participants tended to over-eat to a similar degree, relative to EST, with EI(MATCH) 20% and 22% greater than EST in MOD and HIGH respectively. Between-condition comparisons demonstrated that EI(MATCH) and EST were significantly lower in MOD

  9. Influence of exercise intensity on skeletal muscle blood flow, O2 extraction and O2 uptake on-kinetics

    DEFF Research Database (Denmark)

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

    2012-01-01

    limit O(2) uptake kinetics during high-intensity exercise. In this study, we made frequent measurements of muscle blood flow, arterial-to-venous O(2) difference (a- difference) and O(2) uptake following the onset of multiple transitions of both low-intensity and high-intensity knee-extension exercise...... in the same subjects. We show that although blood flow kinetics is slower for high-intensity compared with low-intensity exercise, this does not result in slower O(2) uptake kinetics. These results indicate that muscle O(2) delivery does not limit O(2) uptake during knee-extension exercise in healthy humans.......Key points Following the start of low-intensity exercise in healthy humans, it has been established that the kinetics of muscle O(2) delivery is faster than, and does not limit, the kinetics of muscle O(2) uptake. Direct data are lacking, however, on the question of whether O(2) delivery might...

  10. Effect of carbohydrate availability on time to exhaustion in exercise performed at two different intensities

    Directory of Open Access Journals (Sweden)

    A.E. Lima-Silva

    2009-05-01

    Full Text Available This study examined the effects of pre-exercise carbohydrate availability on the time to exhaustion for moderate and heavy exercise. Seven men participated in a randomized order in two diet and exercise regimens each lasting 3 days with a 1-week interval for washout. The tests were performed at 50% of the difference between the first (LT1 and second (LT2 lactate breakpoint for moderate exercise (below LT2 and at 25% of the difference between the maximal load and LT2 for heavy exercise (above LT2 until exhaustion. Forty-eight hours before each experimental session, subjects performed a 90-min cycling exercise followed by 5-min rest periods and a subsequent 1-min cycling bout at 125% VO2max/1-min rest periods until exhaustion to deplete muscle glycogen. A diet providing 10% (CHOlow or 65% (CHOmod energy as carbohydrates was consumed for 2 days until the day of the experimental test. In the exercise below LT2, time to exhaustion did not differ between the CHOmod and the CHOlow diets (57.22 ± 24.24 vs 57.16 ± 25.24 min. In the exercise above LT2, time to exhaustion decreased significantly from 23.16 ± 8.76 min on the CHOmod diet to 18.30 ± 5.86 min on the CHOlow diet (P < 0.05. The rate of carbohydrate oxidation, respiratory exchange ratio and blood lactate concentration were reduced for CHOlow only during exercise above LT2. These results suggest that muscle glycogen depletion followed by a period of a low carbohydrate diet impairs high-intensity exercise performance.

  11. Comparison of Acute Physiological and Psychological Responses Between Moderate Intensity Continuous Exercise and three Regimes of High Intensity Training.

    Science.gov (United States)

    Green, Nicole; Wertz, Timothy; LaPorta, Zachary; Mora, Adam; Serbas, Jasmine; Astorino, Todd A

    2017-07-19

    High intensity interval training (HIIT) elicits similar physiological adaptations as moderate intensity continuous training (MICT) despite less time commitment. However, there is debate whether HIIT is more aversive than MICT. This study compared physiological and perceptual responses between MICT and three regimes of HIIT. Nineteen active adults (age = 24.0 ± 3.3 yr) unfamiliar with HIIT initially performed ramp exercise to exhaustion to measure maximal oxygen uptake (VO2 max) and determine workload for subsequent sessions, whose order was randomized. Sprint interval training (SIT) consisted of six 20 s bouts of "all-out" cycling at 140% of maximum watts (Wmax). Low volume (HIITLV) and high volume HIIT (HIITHV) consisted of eight 60 s bouts at 85% Wmax and six 2 min bouts at 70% Wmax, respectively. MICT consisted of 25 min at 40% Wmax. Across regimes, work was not matched. Heart rate, VO2, blood lactate concentration (BLa), affect, and rating of perceived exertion (RPE) were assessed during exercise. Ten minutes post-exercise, Physical Activity Enjoyment (PACES) was measured via a survey. Results revealed significantly higher (pregimes versus MICT at 50, 75, and 100 % of session duration, PACES was similar across regimes (p=0.65) although it was higher in women (p=0.03). Findings from healthy adults unaccustomed to interval training demonstrate that HIIT and SIT are perceived as enjoyable as MICT despite being more aversive.

  12. High-intensity training vs. traditional exercise interventions for promoting health

    DEFF Research Database (Denmark)

    Nybo, Lars; Sundstrup, Emil; Jakobsen, Markus D.

    2010-01-01

    PURPOSE:: to determine the effectiveness of brief intense interval training as exercise intervention for promoting health and evaluate potential benefits with reference to common interventions; i.e. prolonged exercise and strength training. METHODS:: 36 untrained men were divided into groups...... that completed 12 weeks of intense interval running (INT; total training time 40 min a week), prolonged running ( approximately 150 min/week), strength training ( approximately 150 min/week) or continued their habitual life-style without participation in physical training. RESULTS:: The improvement...... in cardiorespiratory fitness was superior in INT (14+/-2% increase in VO2max) compared to the other two exercise interventions (7+/-2% and 3+/-2% increases). The blood glucose concentration 2 hours following oral ingestion of 75 g of glucose was lowered to a similar extent following training in the INT (from 6...

  13. Randomized controlled trial of the effects of high intensity and low-to-moderate intensity exercise on physical fitness and fatigue in cancer survivors: results of the Resistance and Endurance exercise After ChemoTherapy (REACT) study

    NARCIS (Netherlands)

    Kampshoff, C.S.; Chin A Paw, M.J.M.; Brug, J.; Twisk, J.W.R.; Schep, G.; Nijziel, M.R.; van Mechelen, W.; Buffart, L.M.

    2015-01-01

    Background: International evidence-based guidelines recommend physical exercise to form part of standard care for all cancer survivors. However, at present, the optimum exercise intensity is unclear. Therefore, we aimed to evaluate the effectiveness of a high intensity (HI) and low-to-moderate

  14. Randomized controlled trial of the effects of high intensity and low-to-moderate intensity exercise on physical fitness and fatigue in cancer survivors: results of the Resistance and Endurance exercise After ChemoTherapy (REACT) study

    NARCIS (Netherlands)

    Kampshoff, C.S.; Chinapaw, M.J.; Brug, J.; Twisk, J.W.R.; Schep, G.; Nijziel, M.R.; Mechelen, W. van; Buffart, L.M.

    2015-01-01

    BACKGROUND: International evidence-based guidelines recommend physical exercise to form part of standard care for all cancer survivors. However, at present, the optimum exercise intensity is unclear. Therefore, we aimed to evaluate the effectiveness of a high intensity (HI) and low-to-moderate

  15. Does intensity or youth affect the neurobiological effect of exercise on major depressive disorder?

    Science.gov (United States)

    Budde, Henning; Velasques, Bruna; Ribeiro, Pedro; Machado, Sergio; Emeljanovas, Arunas; Kamandulis, Sigitas; Skurvydas, Albertas; Wegner, Mirko

    2018-01-01

    The purpose of this commentary is to discuss the different neurobiological effects of exercise on major depressive disorder (MDD) in children and adolescents and to provide additional explanations to this well written systematic review. This commentary highlights the effects of exercise on the hypothalamic-pituitary-adrenal (HPA) axis, which plays a crucial role in MDD. We address the questions of whether age and different exercise intensities may provide additional information on the neurobiological effects of acute or chronic exercise on MDD. Previous findings clearly suggest that the etiology of MDD is complex and multifaceted, involving numerous neurobiological systems, which are additionally influenced by these two factors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Scapular muscle activity from selected strengthening exercises performed at low and high intensity

    DEFF Research Database (Denmark)

    Andersen, Christoffer H; Zebis, Mette K; Saervoll, Charlotte

    2012-01-01

    practical implications for exercise prescription for optimal shoulder function. For example, both workers with neck pain and athletes at risk of shoulder impingement (e.g. overhead sports) should perform push-up plus and press-up to specifically strengthen the serratus anterior and lower trapezius.......A balanced level of muscle strength between the different parts of the scapular muscles is important to optimize performance and prevent injuries in athletes. Emerging evidence suggests that many athletes lack balanced strength in the scapular muscles. Evidence based recommendations are important...... for proper exercise prescription. This study determines scapular muscle activity during strengthening exercises for scapular muscles performed at low and high intensities (Borg-CR10 level 3 and 8). Surface electromyography (EMG) from selected scapular muscles was recorded during seven strengthening exercises...

  17. Long term high intensity exercise and damage of small joints in rheumatoid arthritis.

    NARCIS (Netherlands)

    Jong, Z. de; Munneke, M.; Zwinderman, A.H.; Kroon, H.M.; Ronday, K.H.; Lems, W.F.; Dijkmans, B.A.C.; Breedveld, F.C.; Vliet Vlieland, T.P.M.; Hazes, J.M.W.; Huizinga, T.W.J.

    2004-01-01

    OBJECTIVE: To investigate the effect of long term high intensity weightbearing exercises on radiological damage of the joints of the hands and feet in patients with rheumatoid arthritis (RA). METHODS: Data of the 281 completers of a 2 year randomised controlled trial comparing the effects of usual

  18. Effects of Respiratory Muscle Warm-up on High-Intensity Exercise Performance

    Directory of Open Access Journals (Sweden)

    Taylor S. Thurston

    2015-11-01

    Full Text Available Exercise performance is partially limited by the functionality of the respiratory musculature. Training these muscles improves steady-state exercise performance. However, less is known about the efficacy of executing a respiratory muscle warm-up (RWU immediately prior to high-intensity exercise. Our study purpose was to use a practitioner-friendly airflow restriction device to investigate the effects of a high, medium, or low intensity RWU on short, high-intensity exercise and pulmonary, cardiovascular, and metabolic function. Eleven recreationally active, males (24.9 ± 4.2 y, 178.8 ± 9.0 cm, 78.5 ± 10.4 kg, 13.4% ± 4.2% body fat cycled at 85% peak power to exhaustion (TTE following four different RWU conditions (separate days, in random order: (1 high; (2 medium; (3 low airflow inspiration restriction, or no RWU. When analyzed as a group, TTE did not improve following any RWU (4.73 ± 0.33 min. However, 10 of the 11 participants improved ≥25 s in one of the three RWU conditions (average = 47.6 ± 13.2 s, which was significantly better than (p < 0.05 the control trial (CON. Neither blood lactate nor perceived difficulty was altered by condition. In general, respiratory exchange ratios were significantly lower during the early stages of TTE in all RWU conditions. Our findings suggest RWU efficacy is predicated on identifying optimal inspiration intensity, which clearly differs between individuals.

  19. Effects of intensive exercise on patients with active rheumatoid arthritis: a randomised clinical trial.

    NARCIS (Netherlands)

    Ende, C.H.M. van den; Breedveld, F.C.; Cessie, S. le; Dijkmans, B.A.C.; Mug, A.W. de

    2000-01-01

    Objectives: To investigate the effects of a dynamic, intensive exercise regimen on pain, disease activity, and physical functioning in active rheumatoid arthritis (RA). Methods: 64 patients with RA with a mean age of 60 (13) years and mean disease duration of 8 (8) years, admitted to hospital

  20. Vigorous intensity exercise for glycemic control in patients with type 1 diabetes.

    Science.gov (United States)

    Yardley, Jane; Mollard, Rebecca; MacIntosh, Andrea; MacMillan, Freya; Wicklow, Brandy; Berard, Lori; Hurd, Carmen; Marks, Seth; McGavock, Jonathan

    2013-12-01

    Regular physical activity has substantial health benefits in persons with type 1 diabetes, including reduced risk of complications and cardiovascular mortality as well as improved self-rated quality of life. Despite these benefits, individuals with type 1 diabetes are often less active than their peers without diabetes. When factors such as time constraints, work pressure and environmental conditions are often cited as barriers to physical activity in the general population, 2 additional major factors may also explain the low rates of physical activity in young people with type 1 diabetes: (1) fear of hypoglycemia both during and after (particularly overnight) exercise and (2) a lack of empiric evidence for the efficacy of physical activity for achieving optimal glycemic control. A number of acute exercise trials recently showed that the inclusion of vigorous intensity physical activity in conventional moderate intensity (i.e. walking and light cycling) exercise sessions may overcome these barriers. No studies have tested the efficacy of high-intensity physical activity on glycemic control (A1C) or post-exercise hypoglycemia in a randomized controlled trial. This article summarizes the literature related to the role of physical activity for the management of blood glucose levels in individuals with type 1 diabetes and provides a rationale for the need of a randomized controlled trial examining the effects of vigorous-intensity physical activity on blood glucose control. Copyright © 2013 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  1. Joint Cooling does not Hinder Athletic Performance during High-intensity Intermittent Exercise.

    Science.gov (United States)

    Kim, H; Lee, D; Choi, H-M; Park, J

    2016-07-01

    We examined the effects of ankle and knee joint cooling on 20-m sprint times and maximal vertical jump heights during high-intensity intermittent exercise. 21 healthy collegiate male basketball (n=14) and handball players (n=7) underwent 3 experimental sessions. Each session consisted of four 15-min quarters of high-intensity intermittent exercises including various intensities of 20-m shuttle running and jumping. A 20-min bilateral joint cooling (ankle, knee, or control-no cooling: in a counterbalanced order) was applied before quarters 1 and 3. After joint cooling, no warm-up activity other than the exercise protocol was given. The 20-m sprint times and maximal vertical jump heights in each experimental session were recorded at baseline (prior to quarter-1) and during each quarter. To test joint cooling effects over time, we performed 3×5 mixed model ANOVAs. Neither ankle nor knee joint cooling changed 20-m sprint times (F8,280=1.45; p=0.18) or maximal vertical jump heights (F8,280=0.76; p=0.64). However, a trend was observed in which joint cooling immediately decreased (quarters 1 and 3) but active warm-up for approximately 20 min improved 20-min sprint times (quarters 2 and 4). Our study suggests that athletic performance such as sprinting and jumping are not altered by joint cooling applied prior to or during high-intensity intermittent exercise. © Georg Thieme Verlag KG Stuttgart · New York.

  2. Serum cardiac troponin I analysis to determine the excessiveness of exercise intensity: A novel equation

    NARCIS (Netherlands)

    Voets, P.J.; Maas, R.P.P.W.M.

    2016-01-01

    Physical exertion is often promoted because of its beneficial health effects. This only holds true, however, as long as the optimal exercise intensity is not exceeded. If physical exertion becomes too strenuous or prolonged, cardiac injury or dysfunction may occur. Consequently, a significant

  3. Motor fatigability after low-intensity hand grip exercises in persons with multiple sclerosis.

    Science.gov (United States)

    Severijns, Deborah; Lemmens, Mieke; Thoelen, Ronald; Feys, Peter

    2016-11-01

    During maximal, sustained contractions, persons with multiple sclerosis (PwMS) show higher motor fatigability in comparison with healthy persons. It is not known if motor fatigability is also different between PwMS and healthy persons during low-intensity exercises. Thus, the aim of this study was to determine the difference in hand grip fatigability between healthy persons and PwMS for both hands during low-intensity hand grip exercises. 19 PwMS and 19 healthy controls performed 18min of hand grip exercises at a maximum of 25% of the maximal voluntary strength, with an electronic hand dynamometer. Perceived fatigability, maximal hand grip strength and muscle activity (electromyography) of the wrist flexors and extensors were recorded in between these exercises for the dominant and non-dominant hand. There was a significant decrease in maximal hand grip strength after exercising in both groups and for both hands, mainly situated in the first 6min. In contrast to what was hypothesized, PwMS did not show more decline in strength than healthy controls, neither in the dominant nor the non-dominant hand. There was no group difference in the increase of the perceived fatigability in the dominant hand. However, for the non-dominant hand, the perceived fatigability after exercising increased more in PwMS than in healthy controls. Additionally, there was no relation between fatigue indices, as assessed with short maximal contractions and the strength decline after low-intensity repetitive exercises. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Pacing and decision making in sport and exercise: the roles of perception and action in the regulation of exercise intensity.

    Science.gov (United States)

    Smits, Benjamin L M; Pepping, Gert-Jan; Hettinga, Florentina J

    2014-06-01

    In pursuit of optimal performance, athletes and physical exercisers alike have to make decisions about how and when to invest their energy. The process of pacing has been associated with the goal-directed regulation of exercise intensity across an exercise bout. The current review explores divergent views on understanding underlying mechanisms of decision making in pacing. Current pacing literature provides a wide range of aspects that might be involved in the determination of an athlete's pacing strategy, but lacks in explaining how perception and action are coupled in establishing behaviour. In contrast, decision-making literature rooted in the understanding that perception and action are coupled provides refreshing perspectives on explaining the mechanisms that underlie natural interactive behaviour. Contrary to the assumption of behaviour that is managed by a higher-order governor that passively constructs internal representations of the world, an ecological approach is considered. According to this approach, knowledge is rooted in the direct experience of meaningful environmental objects and events in individual environmental processes. To assist a neuropsychological explanation of decision making in exercise regulation, the relevance of the affordance competition hypothesis is explored. By considering pacing as a behavioural expression of continuous decision making, new insights on underlying mechanisms in pacing and optimal performance can be developed.

  5. 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

  6. Irisin in blood increases transiently after single sessions of intense endurance exercise and heavy strength training.

    Directory of Open Access Journals (Sweden)

    Håvard Nygaard

    Full Text Available Irisin is a recently identified exercise-induced hormone that increases energy expenditure, at least in rodents. The main purpose of this study was to test the hypothesis that Irisin increases acutely in blood after singular sessions of intense endurance exercise (END and heavy strength training (STR. Secondary, we wanted to explore the relationship between body composition and exercise-induced effects on irisin, and the effect of END and STR on muscular expression of the irisin gene FNDC5.Nine moderately trained healthy subjects performed three test days using a randomized and standardized crossover design: one day with 60 minutes of END, one day with 60 minutes of STR, and one day without exercise (CON. Venous blood was sampled over a period of 24h on the exercise days.Both END and STR led to transient increases in irisin concentrations in blood, peaking immediately after END and one hour after STR, before gradually returning to baseline. Irisin responses to STR, but not END, showed a consistently strong negative correlation with proportions of lean body mass. Neither END nor STR affected expression of FNDC5, measured 4h after training sessions, though both protocols led to pronounced increases in PGC-1α expression, which is involved in transcriptional control of FNDC5.The results strongly suggest that single sessions of intense endurance exercise and heavy strength training lead to transient increases in irisin concentrations in blood. This was not accompanied by increased FNDC5 expression, measured 4h post-exercise. The results suggest that irisin responses to resistance exercise are higher in individuals with lower proportions of lean body mass.

  7. Dissociating external power from intramuscular exercise intensity during intermittent bilateral knee-extension in humans.

    Science.gov (United States)

    Davies, Matthew J; Benson, Alan P; Cannon, Daniel T; Marwood, Simon; Kemp, Graham J; Rossiter, Harry B; Ferguson, Carrie

    2017-08-04

    Continuous high-intensity constant-power exercise is unsustainable, with maximal oxygen uptake (V̇O2 max ) and the limit of tolerance attained after only a few minutes. Performing the same power intermittently reduces the O2 cost of exercise and increases tolerance. The extent to which this dissociation is reflected in the intramuscular bioenergetics is unknown. We used pulmonary gas exchange and (31) P magnetic resonance spectroscopy to measure whole-body V̇O2, quadriceps phosphate metabolism and pH during continuous and intermittent exercise of different work:recovery durations. Shortening the work:recovery durations (16:32 s vs. 32:64 s vs. 64:128 s vs. continuous) at a work rate estimated to require 110% peak aerobic power reduced V̇O2, muscle phosphocreatine breakdown and muscle acidification, eliminated the glycolytic-associated contribution to ATP synthesis, and increased exercise tolerance. Exercise intensity (i.e. magnitude of intramuscular metabolic perturbations) can be dissociated from the external power using intermittent exercise with short work:recovery durations. Compared with work-matched high-intensity continuous exercise, intermittent exercise dissociates pulmonary oxygen uptake (V̇O2) from the accumulated work. The extent to which this reflects differences in O2 storage fluctuations and/or contributions from oxidative and substrate-level bioenergetics is unknown. Using pulmonary gas-exchange and intramuscular (31) P magnetic resonance spectroscopy, we tested the hypotheses that, at the same power: ATP synthesis rates are similar, whereas peak V̇O2 amplitude is lower in intermittent vs. continuous exercise. Thus, we expected that: intermittent exercise relies less upon anaerobic glycolysis for ATP provision than continuous exercise; shorter intervals would require relatively greater fluctuations in intramuscular bioenergetics than in V̇O2 compared to longer intervals. Six men performed bilateral knee-extensor exercise (estimated to

  8. Dissociating external power from intramuscular exercise intensity during intermittent bilateral knee‐extension in humans

    Science.gov (United States)

    Davies, Matthew J.; Benson, Alan P.; Cannon, Daniel T.; Marwood, Simon; Kemp, Graham J.; Rossiter, Harry B.

    2017-01-01

    Key points Continuous high‐intensity constant‐power exercise is unsustainable, with maximal oxygen uptake (V˙O2 max ) and the limit of tolerance attained after only a few minutes.Performing the same power intermittently reduces the O2 cost of exercise and increases tolerance. The extent to which this dissociation is reflected in the intramuscular bioenergetics is unknown.We used pulmonary gas exchange and 31P magnetic resonance spectroscopy to measure whole‐body V˙O2, quadriceps phosphate metabolism and pH during continuous and intermittent exercise of different work:recovery durations.Shortening the work:recovery durations (16:32 s vs. 32:64 s vs. 64:128 s vs. continuous) at a work rate estimated to require 110% peak aerobic power reduced V˙O2, muscle phosphocreatine breakdown and muscle acidification, eliminated the glycolytic‐associated contribution to ATP synthesis, and increased exercise tolerance.Exercise intensity (i.e. magnitude of intramuscular metabolic perturbations) can be dissociated from the external power using intermittent exercise with short work:recovery durations. Abstract Compared with work‐matched high‐intensity continuous exercise, intermittent exercise dissociates pulmonary oxygen uptake (V˙O2) from the accumulated work. The extent to which this reflects differences in O2 storage fluctuations and/or contributions from oxidative and substrate‐level bioenergetics is unknown. Using pulmonary gas‐exchange and intramuscular 31P magnetic resonance spectroscopy, we tested the hypotheses that, at the same power: ATP synthesis rates are similar, whereas peak V˙O2 amplitude is lower in intermittent vs. continuous exercise. Thus, we expected that: intermittent exercise relies less upon anaerobic glycolysis for ATP provision than continuous exercise; shorter intervals would require relatively greater fluctuations in intramuscular bioenergetics than in V˙O2 compared to longer intervals. Six men performed bilateral knee

  9. Perspectives on high-intensity interval exercise for health promotion in children and adolescents

    Science.gov (United States)

    Bond, Bert; Weston, Kathryn L; Williams, Craig A; Barker, Alan R

    2017-01-01

    Physical activity lowers future cardiovascular disease (CVD) risk; however, few children and adolescents achieve the recommended minimum amount of daily activity. Accordingly, there is virtue in identifying the efficacy of small volumes of high-intensity exercise for health benefits in children and adolescents for the primary prevention of CVD risk. The purpose of this narrative review is to provide a novel overview of the available literature concerning high-intensity interval-exercise (HIIE) interventions in children and adolescents. Specifically, the following areas are addressed: 1) outlining the health benefits observed following a single bout of HIIE, 2) reviewing the role of HIIE training in the management of pediatric obesity, and 3) discussing the effectiveness of school-based HIIE training. In total, 39 HIIE intervention studies were included in this review. Based upon the available data, a single bout of high-intensity exercise provides a potent stimulus for favorable, acute changes across a range of cardiometabolic outcomes that are often superior to a comparative bout of moderate-intensity exercise (14 studies reviewed). HIIE also promotes improvements in cardiorespiratory fitness and cardiometabolic health status in overweight and obese children and adolescents (10 studies reviewed) and when delivered in the school setting (15 studies reviewed). We thus conclude that high-intensity exercise is a feasible and potent method of improving a range of cardiometabolic outcomes in children and adolescents. However, further work is needed to optimize the delivery of HIIE interventions in terms of participant enjoyment and acceptability, to include a wider range of health outcomes, and to control for important confounding variables (eg, changes in diet and habitual physical activity). Finally, research into the application of HIIE training interventions to children and adolescents of different ages, sexes, pubertal status, and sociocultural backgrounds is

  10. 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.

  11. Pragmatic randomised controlled trial of preferred intensity exercise in women living with depression

    Directory of Open Access Journals (Sweden)

    Morres Ioannis

    2011-06-01

    Full Text Available Abstract Background Exercise may be effective in treating depression, but trials testing its effect in depressed women are rare. Aim To compare the effect of exercise of preferred intensity with exercise of prescribed intensity in thirty-eight women living with depression. Methods A Pragmatic RCT of 12 sessions of exercise at preferred intensity compared with 12 sessions at prescribed intensity. Beck Depression Inventory (BDI, Rosenberg Self Esteem Scale (RSES, General Health Questionnaire 12 (GHQ-12, heart rate (HR, Rating of Perceived Exertion Scale (RPE, Quality of Life in Depression Scale (QLDS, Multi-Dimensional Scale of Perceived Social Support (MDSPSS, SF12 Health Survey and exercise participation rates were compared between groups. Results Intervention participants had statistically better BDI (t = 2.638, df = 36, p = 0.006, 95% mean (SD 26.5 (10.7, CI-20.4 to -2.7, d = 0.86, GHQ-12 (t = 3.284, df = 36, p = 0.001, mean (SD 8.3 (3.7 95% CI -6.5 to -1.5, d = 1.08, RSES (t = 2.045, df = 36, p = 0.024, mean (SD 11.3 (5.8, 95% CI 0.3 -6.4, d = 0.25, QLDS (t = 1.902, df = 36, p = 0.0325, mean (SD 15.5 (7.9, 95% CI -12.2 -0.4, d = 0.27 RPE scores (t = 1.755, df = 36, p = 0.0475, mean (SD 9.2 (3.2, 95% CI -.5 - 5.2, d = 0.77 and attended more exercise sessions (t = 1.781, df = 36, p = 0.0415, number of sessions 8 (65%, 95% CI-0.3 -4.8, d = 0.58. SF-12, MSPSS and HR did not differ significantly between groups. Conclusions Exercise of preferred intensity improves psychological, physiological and social outcomes, and exercise participation rates in women living with depression. Trial Registration ClinicalTrials.gov: NCT00546221

  12. Appetite, food intake and gut hormone responses to intense aerobic exercise of different duration.

    Science.gov (United States)

    Holliday, Adrian; Blannin, Andrew

    2017-12-01

    The purpose of the study is to investigate the effect of acute bouts of high-intensity aerobic exercise of differing durations on subjective appetite, food intake and appetite-associated hormones in endurance-trained males. Twelve endurance-trained males (age = 21 ± 2 years; BMI = 21.0 ± 1.6 kg/m2; VO2max = 61.6 ± 6.0 mL/kg/min) completed four trials, within a maximum 28 day period, in a counterbalanced order: resting (REST); 15 min exercise bout (15-min); 30 min exercise bout (30-min) and 45 min exercise bout (45-min). All exercise was completed on a cycle ergometer at an intensity of ~76% VO2max Sixty minutes post exercise, participants consumed an ad libitum meal. Measures of subjective appetite and blood samples were obtained throughout the morning, with plasma analyzed for acylated ghrelin, total polypeptide tyrosine-tyrosine (PYY) and total glucagon-like peptide 1 (GLP-1) concentrations. The following results were obtained: Neither subjective appetite nor absolute food intake differed between trials. Relative energy intake (intake - expenditure) was significantly greater after REST (2641 ± 1616 kJ) compared with both 30-min (1039 ± 1520 kJ) and 45-min (260 ± 1731 kJ), and significantly greater after 15-min (2699 ± 1239 kJ) compared with 45-min (condition main effect, P exercise in 30-min and 45-min, respectively (condition × time interaction, P exercise trials (condition × time interaction, P = 0.011); the greatest, most enduring suppression, was observed in 45-min. PYY concentration was unchanged with exercise. In conclusion, high-intensity aerobic cycling lasting up to 45 min did not suppress subjective appetite or affect absolute food intake, but did reduce relative energy intake, in well-trained endurance athletes. Findings question the role of appetite hormones in regulating subjective appetite in the acute post-exercise period. © 2017 Society for Endocrinology.

  13. Leg oxygen uptake in the initial phase of intense exercise is slowed by a marked reduction in oxygen delivery

    DEFF Research Database (Denmark)

    Christensen, Peter Møller; Nyberg, Michael Permin; Mortensen, Stefan Peter

    2013-01-01

    The present study examined if a marked reduction in oxygen delivery, unlike findings with moderate intensity exercise, would slow leg oxygen uptake (VO2) kinetics during intense exercise (86±3% of incremental test peak power). Seven healthy males (26±1 years, mean±SEM) performed one-legged knee-e...

  14. Intense intermittent exercise provides weak stimulus for vascular endothelial growth factor secretion and capillary growth in skeletal muscle

    DEFF Research Database (Denmark)

    Høier, Birgitte; Passos, Madla; Bangsbo, Jens

    2013-01-01

    The effect of acute intense intermittent exercise compared to moderate intensity exercise, on angiogenic factors and the effect of four weeks of intense intermittent training on capillary growth were examined in nine young healthy males, pre-conditioned by moderate intensity endurance training...... for VEGF secretion and endothelial cell proliferation and that intense intermittent training does not induce a sufficient angiogenic stimulus to induce capillary growth in muscle previously conditioned by moderate intensity exercise........ The intense training consisted of 24 one-min cycling bouts at an initial work rate of 316 ± 19W (~117% of pre VO2 max), performed 3 times/week. Skeletal muscle biopsies and muscle microdialysates were otained from m.v. lateralis before, during, and after acute exercise performed at either moderate or high...

  15. Effect of low-intensity training on transient kinetics of pulmonary oxygen uptake during moderate-intensity cycle exercise.

    Science.gov (United States)

    Hamasaki, A; Arima, S; Mitsuzono, R; Hirakoba, K

    2015-10-01

    It is unclear whether the slowed time constant of phase II in pulmonary oxygen uptake on-kinetics (V̇O2τ) in unfit and inactive men would be shortened by low exercise intensity (low-intensity) walking training. We therefore tested the hypothesis that the slowed V̇O2τ in sedentary population would speed up due to low-intensity walking training with high volume. Ten unfit and inactive male subjects (aged 26 to 50 yrs) underwent a low-intensity (30-40% of V̇O2max), long-duration (>60 min) training in the form of walking exercise 3-4 times a week for 12 weeks. We prospectively collected data on anthropometric, maximal oxygen uptake (V̇O2max), time constant of heart rate (HRτ) and V̇O2τ before training (0 wk; Pre) and every six weeks (6 wk; Mid, 12 wk; Post) from the beginning of the training. Anthropometric variables and V̇O2max showed no significant changes throughout the training program, whereas HRτ showed a tendency to be shortened with a progress of the training with no significant change. The slowed V̇O2τ at Pre (47.6±5.6 s) remained almost unchanged at Mid (48.8±4.9 s), but had a significant decrease at Post (40.5±7.9 s, Pintensity walking training is thought to occur presumably owing to an improved matching of oxygen delivery to oxygen utilization at the site of gas exchange in active muscle tissue. We concluded that low-intensity walking training at beginning stage of training could contribute to the acceleration of the slowed V̇O2τ in unfit and inactive subjects.

  16. Sex differences in lipolysis-regulating mechanisms in overweight subjects: effect of exercise intensity.

    Science.gov (United States)

    Moro, Cédric; Pillard, Fabien; de Glisezinski, Isabelle; Crampes, François; Thalamas, Claire; Harant, Isabelle; Marques, Marie-Adeline; Lafontan, Max; Berlan, Michel

    2007-09-01

    To explore sex differences in the regulation of lipolysis during exercise, the lipid-mobilizing mechanisms in the subcutaneous adipose tissue (SCAT) of overweight men and women were studied using microdialysis. Subjects matched for age, BMI, and physical fitness performed two 30-minute exercise bouts in a randomized fashion: the first test at 30% and 50% of their individual maximal oxygen uptake (Vo(2max)) and the second test at 30% and 70% of their Vo(2max). In both groups, an exercise-dependent increment in extracellular glycerol concentration (EGC) was observed. Whatever the intensity, phentolamine [alpha-adrenergic receptor (AR) antagonist] added to a dialysis probe potentiated exercise-induced lipolysis only in men. In a probe containing phentolamine plus propranolol (beta-AR antagonist), no changes in EGC occurred when compared with the control probe when exercise was performed at 30% and 50% Vo(2max). A significant reduction of EGC (when compared with the control probe) was observed in women at 70% Vo(2max). At each exercise power, the plasma non-esterified fatty acid and glycerol concentrations were higher in women. Exercise-induced increase in plasma catecholamine levels was lower in women compared with men. Plasma insulin decreased and atrial natriuretic peptide increased similarly in both groups. Overweight women mobilize more lipids (assessed by glycerol) than men during exercise. alpha(2)-Anti-lipolytic effect was functional in SCAT of men only. The major finding is that during low-to-moderate exercise periods (30% and 50% Vo(2max)), lipid mobilization in SCAT relies less on catecholamine-dependent stimulation of beta-ARs than on an increase in plasma atrial natriuretic peptide concentrations and the decrease in plasma insulin.

  17. High-Intensity Exercise and Carbohydrate Supplementation do not Alter Plasma Visfatin

    Directory of Open Access Journals (Sweden)

    Paul F. Mellick, Bryan J. Feger, Douglas J. Oberlin, Paul G. Davis, Laurie Wideman

    2017-03-01

    Full Text Available The purpose of the study was to examine the effect of high-intensity exercise and carbohydrate supplementation (CHO on plasma visfatin. On 2 separate days, 10 sprint-trained males (age = 26.4 ± 5.3 yr; Ht = 1.77 ± 0.03 m; Wt = 78.78 ± 9.10 kg; BF% = 13.96 ± 7.28% completed 4, 3-min bouts of cycling at 50% mean anaerobic power, with 6 min of rest between bouts. On CHO day, subjects ingested 50g of CHO 30 min before exercise. On control day, subjects ingested a sugar-free drink (CON 30 min before exercise. Blood was drawn before supplementation, 15 min before exercise, before and after each exercise bout, and 15 and 30 min post exercise. Visfatin, glucose, and insulin were determined. Truncal fat was assessed by dual energy x-ray. Visfatin was not significantly different between treatments (CHO vs CON at any time point (p = 0.163, and was not significantly altered by exercise (p = 0.692. Insulin [25.65 vs 8.35 mU/l, CHO vs CON, respectively] and glucose [138.57 vs 98.10 mg/dl, CHO vs CON, respectively] were significantly elevated after CHO ingestion and remained elevated throughout the first half of exercise. Baseline visfatin was significantly correlated with truncal fat (r2 = 0.7782, p < 0.05. Visfatin was correlated to truncal fat in sprint-trained males, but was not altered by exercise or CHO supplementation.

  18. High Intensity Exercise Countermeasures does not Prevent Orthostatic Intolerance Following Prolonged Bed Rest

    Science.gov (United States)

    Platts, Steven H.; Stenger, Michael B.; Ploutz-Snyder, Lori L.; Lee, Stuart M. C.

    2014-01-01

    Approximately 20% of Space Shuttle astronauts became presyncopal during operational stand and 80deg head-up tilt tests, and the prevalence of orthostatic intolerance increases after longer missions. Greater than 60% of the US astronauts participating in Mir and early International Space Station missions experienced presyncope during post-flight tilt tests, perhaps related to limitations of the exercise hardware that prevented high intensity exercise training until later ISS missions. The objective of this study was to determine whether an intense resistive and aerobic exercise countermeasure program designed to prevent cardiovascular and musculoskeletal deconditioning during 70 d of bed rest (BR), a space flight analog, would protect against post-BR orthostatic intolerance. METHODS Twenty-six subjects were randomly assigned to one of three groups: non-exercise controls (n=11) or one of two exercise groups (ExA, n=8; ExB, n=7). Both ExA and ExB groups performed the same resistive and aerobic exercise countermeasures during BR, but one exercise group received testosterone supplementation while the other received a placebo during BR in a double-blinded fashion. On 3 d/wk, subjects performed lower body resistive exercise and 30 min of continuous aerobic exercise (=75% max heart rate). On the other 3 d/wk, subjects performed only highintensity, interval-style aerobic exercise. Orthostatic intolerance was assessed using a 15-min 80? head-up tilt test performed 2 d (BR-2) before and on the last day of BR (BR70). Plasma volume was measured using carbon monoxide rebreathing on BR-3 and before rising on the first recovery day (BR+0). The code for the exercise groups has not been broken, and results are reported here without group identification. RESULTS Only one subject became presyncopal during tilt testing on BR-2, but 7 of 11 (63%) controls, 3 of 8 (38%) ExA, and 4 of 7 (57%) ExB subjects were presyncopal on BR70. Survival analysis of post-BR tilt tests revealed no

  19. High-intensity intermittent exercise training with chlorella intake accelerates exercise performance and muscle glycolytic and oxidative capacity in rats.

    Science.gov (United States)

    Horii, Naoki; Hasegawa, Natsuki; Fujie, Shumpei; Uchida, Masataka; Miyamoto-Mikami, Eri; Hashimoto, Takeshi; Tabata, Izumi; Iemitsu, Motoyuki

    2017-04-01

    The purpose of this study was to investigate the effect of chronic chlorella intake alone or in combination with high-intensity intermittent exercise (HIIE) training on exercise performance and muscle glycolytic and oxidative metabolism in rats. Forty male Sprague-Dawley rats were randomly assigned to the four groups: sedentary control, chlorella intake (0.5% chlorella powder in normal feed), HIIE training, and combination of HIIE training and chlorella intake for 6 wk ( n = 10 each group). HIIE training comprised 14 repeats of a 20-s swimming session with a 10-s pause between sessions, while bearing a weight equivalent to 16% of body weight, 4 days/week. Exercise performance was tested after the interventions by measuring the maximal number of HIIE sessions that could be completed. Chlorella intake and HIIE training significantly increased the maximal number of HIIE sessions and enhanced the expression of monocarboxylate transporter (MCT)1, MCT4, and peroxisome proliferator-activated receptor γ coactivator-1α concomitantly with the activities of lactate dehydrogenase (LDH), phosphofructokinase, citrate synthase (CS), and cytochrome- c oxidase (COX) in the red region of the gastrocnemius muscle. Furthermore, the combination further augmented the increased exercise performance and the enhanced expressions and activities. By contrast, in the white region of the muscle, MCT1 expression and LDH, CS, and COX activities did not change. These results showed that compared with only chlorella intake and only HIIE training, chlorella intake combined with HIIE training has a more pronounced effect on exercise performance and muscle glycolytic and oxidative metabolism, in particular, lactate metabolism. Copyright © 2017 the American Physiological Society.

  20. Blood flow measurement of human skeletal muscle during various exercise intensity using diffuse correlation spectroscopy (DCS)

    Science.gov (United States)

    Murakami, Yuya; Ono, Yumie; Ichinose, Masashi

    2017-02-01

    We studied blood flow dynamics of active skeletal muscle using diffuse correlation spectroscopy (DCS), an emerging optical modality that is suitable for noninvasive quantification of microcirculation level in deep tissue. Seven healthy subjects conducted 0.5 Hz dynamic handgrip exercise for 3 minutes at intensities of 10, 20, 30, and 50 % of maximal voluntary contraction (MVC). DCS could detect the time-dependent increase of the blood flow response of the forearm muscle for continuous exercises, and the increase ratios of the mean blood flow through the exercise periods showed good correlation with the exercise intensities. We also compared blood flow responses detected from DCS with two different photon sampling rates and found that an appropriate photon sampling rates should be selected to follow the wide-ranged increase in the muscle blood flow with dynamic exercise. Our results demonstrate the possibility for utilizing DCS in a field of sports medicine to noninvasively evaluate the dynamics of blood flow in the active muscles.

  1. A MOTIVATIONAL MUSIC AND VIDEO INTERVENTION IMPROVES HIGH-INTENSITY EXERCISE PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Martin J. Barwood

    2009-09-01

    Full Text Available Music and video are utilised by recreational gym users to enhance their exercise experience. Music and video have not been investigated for their combined ergogenic effect during high intensity exercise. To induce fatigue, this study was performed in warm (~26°C, moist conditions (~50%RH. Six, non-acclimated, male participants took part in the study. Each participant completed three 30-minute exercise bouts on a motorised treadmill under three counterbalanced conditions on separate days: control (CON, motivational music plus video intervention (M, non-motivational intervention (NM. They completed a warm-up (5 km·h-1 [5 minutes], 9km·h-1 [10 minutes] followed by a maximal effort run (15 minutes. Participants did not receive any feedback of time elapsed, distance run or speed. Measures: Distance covered (metres, heart rate, blood lactate accumulation (Blac and ratings of perceived exertion (RPE. Participants in the M condition ran significantly further than in the NM (M: 3524 [388]metres; NM: 3110 [561]metres; CON: 3273 [458]metres and CON conditions, accumulated more Blac, but did not increase their peak RPE rating (p < 0.05. The M intervention improved tolerance of high intensity exercise in warm conditions. It was proposed that a change in attentional processing from internal (physical sensations to external perspective (music and video may have facilitated this improvement. These findings have strong implications for improving health, fitness and engagement in gym-based exercise programs

  2. Low-frequency severe-intensity interval training improves cardiorespiratory functions.

    Science.gov (United States)

    Nakahara, Hidehiro; Ueda, Shin-Ya; Miyamoto, Tadayoshi

    2015-04-01

    The present study investigated the effects of severe-intensity interval training at a frequency of once a week on cardiorespiratory function at rest and during exercise. Fourteen young healthy males were randomly assigned to either an interval training group or control group. Cardiorespiratory function was investigated by incremental maximal exercise test and constant work rate submaximal exercise test before and after the intervention period in all subjects. Submaximal exercise test was conducted at two work rates (80% ventilatory threshold (VT) level and 100% VT level plus 50% of the difference between VT and peak oxygen consumption (V˙O2)) for 8 min; the same work rates and duration were used before and after training. Left ventricular adaptations were assessed by echocardiography under supine resting conditions before and after training. In the interval training group, seven subjects performed cycle ergometer training once per week for 3 months. The training consisted of three bouts of exercises to volitional fatigue at 80% maximum work rate. Increased V˙O2max (+13%, P = 0.015), VT (+21%, P = 0.001), and left ventricular posterior wall thickness (+18%, P = 0.002) and reduced minute ventilation (-12%, P = 0.032) and blood lactate concentration (-16%, P = 0.025) during high-intensity exercise were observed after the training program compared with baseline. Although not significant, V˙O2 and cycling economy (V˙O2 per work rate) during high-intensity exercise decreased slightly after training. The present results indicate that severe-intensity interval training, even when performed at a low frequency, markedly improves cardiorespiratory function as well as induces cardiac morphological adaptations involving left ventricular hypertrophy and cardiorespiratory metabolic response during submaximal exercise. The present findings may provide new insights for low-frequency, severe-intensity interval training in the field of sports science.

  3. HIGH INTENSITY EXERCISE AND FLEXIBILITY OF THE LOWER LIMBS: DOSE-EFFECT STUDY

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    João Rafael Valentim-Silva

    Full Text Available ABSTRACT Introduction: Sports scientists have been studying the phenomenon involving different types of exercises and their influence on other activities. Stretching exercises have a negative influence on muscular strength and power output, as do high intensity or long duration cardiovascular training. Nevertheless, several studies have found the opposite to be true Nevertheless, few investigations have studied the opposite. Objective: To determine whether high intensity power exercise influences muscular flexibility in an acute manner. Methods: A sample of forty-three male and female young adults aged between 18 and 28 years, with a mean age of 22.88 + 3.04 years, who have practiced physical activity for at least six months. To determine flexibility, the sit-and-reach test was used. For the high intensity training, a 45º leg press was used. A 10-rep movement was performed at 85% of 1 RM, in both pre- and post-tests. Statistic analysis was conducted using the ANOVA and Scheffer's post-hoc tests, with a level of significance for differences of < 0.05. Results: Comparison of the pre- and post-tests proved to be statistically significant from the baseline from the fourth to the seventh repetitions. Conclusion: Strength exercises at 85% of 1RM seem to significantly increase range of motion in an acute manner, and the growth of this range of motion has a dose-effect response.

  4. Reliability of telemetric electromyography and near-infrared spectroscopy during high-intensity resistance exercise.

    Science.gov (United States)

    Scott, Brendan R; Slattery, Katie M; Sculley, Dean V; Lockie, Robert G; Dascombe, Ben J

    2014-10-01

    This study quantified the inter- and intra-test reliability of telemetric surface electromyography (EMG) and near infrared spectroscopy (NIRS) during resistance exercise. Twelve well-trained young men performed high-intensity back squat exercise (12 sets at 70-90% 1-repetition maximum) on two occasions, during which EMG and NIRS continuously monitored muscle activation and oxygenation of the thigh muscles. Intra-test reliability for EMG and NIRS variables was generally higher than inter-test reliability. EMG median frequency variables were generally more reliable than amplitude-based variables. The reliability of EMG measures was not related to the intensity or number of repetitions performed during the set. No notable differences were evident in the reliability of EMG between different agonist muscles. NIRS-derived measures of oxyhaemoglobin, deoxyhaemoglobin and tissue saturation index were generally more reliable during single-repetition sets than multiple-repetition sets at the same intensity. Tissue saturation index was the most reliable NIRS variable. Although the reliability of the EMG and NIRS measures varied across the exercise protocol, the precise causes of this variability are not yet understood. However, it is likely that biological variation during multi-joint isotonic resistance exercise may account for some of the variation in the observed results. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Locomotor muscle fatigue does not alter oxygen uptake kinetics during high-intensity exercise

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    James Hopker

    2016-10-01

    Full Text Available The slow component (VO2sc that develops during high-intensity aerobic exercise is thought to be strongly associated with locomotor muscle fatigue. We sought to experimentally test this hypothesis by pre-fatiguing the locomotor muscles used during subsequent high-intensity cycling exercise. Over two separate visits, eight healthy male participants were asked to either perform a non-metabolically stressful 100 intermittent drop-jumps protocol (pre fatigue condition or rest for 33 minutes (control condition according to a random and counterbalanced order. Locomotor muscle fatigue was quantified with 6-second maximal sprints at a fixed pedaling cadence of 90 rev·min-1. Oxygen kinetics and other responses (heart rate, capillary blood lactate concentration and rating of perceived exertion, RPE were measured during two subsequent bouts of 6 min cycling exercise at 50% of the delta between the lactate threshold and VO2max determined during a preliminary incremental exercise test. All tests were performed on the same cycle ergometer. Despite significant locomotor muscle fatigue (P = 0.03, the VO2sc was not significantly different between the pre fatigue (464 ± 301 mL·min-1 and the control (556 ± 223 mL·min-1 condition (P = 0.50. Blood lactate response was not significantly different between conditions (P = 0.48 but RPE was significantly higher following the pre-fatiguing exercise protocol compared with the control condition (P < 0.01 suggesting higher muscle recruitment. These results demonstrate experimentally that locomotor muscle fatigue does not significantly alter the VO2 kinetic response to high intensity aerobic exercise, and challenge the hypothesis that the VO2sc is strongly associated with locomotor muscle fatigue.

  6. Where does HIT fit? An examination of the affective response to high-intensity intervals in comparison to continuous moderate- and continuous vigorous-intensity exercise in the exercise intensity-affect continuum.

    Directory of Open Access Journals (Sweden)

    Mary E Jung

    Full Text Available Affect experienced during an exercise session is purported to predict future exercise behaviour. Compared to continuous moderate-intensity exercise (CMI, the affective response to continuous vigorous-intensity exercise (CVI has consistently been shown to be more aversive. The affective response, and overall tolerability to high-intensity interval training (HIT, is less studied. To date, there has yet to be a comparison between HIT, CVI, and CMI. The purpose of this study was to compare the tolerability and affective responses during HIT to CVI and CMI. This study utilized a repeated measures, randomized, counter-balanced design. Forty-four participants visited the laboratory on four occasions. Baseline fitness testing was conducted to establish peak power output in Watts (W peak. Three subsequent visits involved a single bout of a HIT, corresponding to 1-minute at ∼ 100% W peak and 1-minute at ∼ 20% W peak for 20 minutes, b CMI, corresponding to ∼ 40% W peak for 40 minutes, and c CVI, corresponding to ∼ 80% W peak for 20 minutes. The order of the sessions was randomized. Affective responses were measured before, during and after each session. Task self-efficacy, intentions, enjoyment and preference were measured after sessions. Participants reported greater enjoyment of HIT as compared to CMI and CVI, with over 50% of participants reporting a preference to engage in HIT as opposed to either CMI or CVI. HIT was considered more pleasurable than CVI after exercise, but less pleasurable than CMI at these times. Despite this participants reported being just as confident to engage in HIT as they were CMI, but less confident to engage in CVI. This study highlights the utility of HIT in inactive individuals, and suggests that it may be a viable alternative to traditionally prescribed continuous modalities of exercise for promoting self-efficacy and enjoyment of exercise.

  7. The effect of low and moderate intensity aerobic exercises on sleep quality in men older adults

    OpenAIRE

    AKBARI KAMRANI, Ahmad Ali; Shams, Amir; Shamsipour Dehkordi, Parvaneh; Mohajeri, Robabeh

    2014-01-01

    Objective: Sleep is an active and complex rhythmic state that may be affected by the aging process. The purpose of present research was to investigate the effect of low and moderate intensity aerobic exercises on sleep quality in older adults. Methods: The research method is quasi-experimental with pre-test and post-test design. The statistical sample included 45 volunteer elderly men with age range of 60-70 years-old that divided randomly in two experimental groups (aerobic exercise with low...

  8. Muscle Activation During Exercise in Severe Acute Hypoxia: Role of Absolute and Relative Intensity

    OpenAIRE

    Torres-Peralta, Rafael; Losa-Reyna, José; González-Izal, Miriam; Perez-Suarez, Ismael; Calle-Herrero, Jaime; Izquierdo, Mikel; Calbet, José A. L.

    2014-01-01

    Torres-Peralta, Rafael, José Losa-Reyna, Miriam González-Izal, Ismael Perez-Suarez, Jaime Calle-Herrero, Mikel Izquierdo, and José A.L. Calbet. Muscle activation during exercise in severe acute hypoxia: Role of absolute and relative intensity. High Alt Med Biol 15:472–482, 2014.—The aim of this study was to determine the influence of severe acute hypoxia on muscle activation during whole body dynamic exercise. Eleven young men performed four incremental cycle ergometer tests to exhaustion bre...

  9. Effectiveness of a community-based low intensity exercise programme for ambulatory stroke survivors.

    Science.gov (United States)

    Cramp, Mary Christine; Greenwood, Richard J; Gill, Michael; Lehmann, Anthea; Rothwell, John Christine; Scott, Oona M

    2010-01-01

    To establish the feasibility and effectiveness of a community-based exercise programme for ambulatory patients with stroke discharged from rehabilitation. Eighteen participants were recruited 3-12 months after onset of first stroke. Using a time series experimental design, the group completed a baseline period of 4 weeks (A1), a group exercise programme of low-intensity progressive resistive exercise and functional tasks for lower limb muscles (B) and repeat assessment after cessation of exercise (A2). Fitness instructors delivered sessions at Leisure Centres twice weekly for 14 weeks with physiotherapy support and the minimum attendance requirement was 16 sessions. Measures included muscle strength, gait velocity, Berg Balance Scale and Nottingham Extended Activities of Daily Living. Lower limb muscle strength improved after training (ANOVA, p exercise sessions. Walking velocity increased significantly (ANOVA, p everyday function were also significantly improved (p benefit. This community-based exercise programme was feasible and delivered positive improvements in physical function for participants. Further issues raised for investigation include the individual response to training and the benefits of extended training.

  10. INSPIRATORY MUSCLE FATIGUE FOLLOWING MODERATE-INTENSITY EXERCISE IN THE HEAT

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    James S. Williams

    2005-09-01

    Full Text Available Heavy exercise has been shown to elicit reductions in inspiratory muscle strength in healthy subjects. Our purpose was to determine the combined effects of moderate-intensity endurance exercise and a thermal load on inspiratory muscle strength in active subjects. Eight active, non heat-acclimatized female subjects (23.5 ± 1.4 yr; VO2max = 39.8 ± 2.4 ml.kg-1.min-1 randomly performed two 40 min endurance exercise bouts (60% VO2max in either a thermo-neutral (22°C/21% RH or hot (37°C/33% RH environment on separate days. Maximal sustained inspiratory mouth pressure (PImax was obtained pre and post exercise as an index of inspiratory muscle strength. Additional variables obtained every 10 min during the endurance exercise bouts included: rectal temperature (TRE, heart rate (HR, minute ventilation (VE, oxygen uptake (VO2, tidal volume (VT, breathing frequency (Fb, and ratings of perceived exertion and dyspnea (RPE/RPD. Data were analyzed with repeated measures ANOVA. PImax was significantly reduced (p 80% VO2max is required to elicit reductions in inspiratory muscle strength. In addition, dyspnea perception during exercise is greater in a hot environment, compared to thermo-neutral, at a similar level of VE and VO2.

  11. 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.

  12. Can You Have Your Vigorous Exercise and Enjoy It Too? Ramping Intensity Down Increases Postexercise, Remembered, and Forecasted Pleasure.

    Science.gov (United States)

    Zenko, Zachary; Ekkekakis, Panteleimon; Ariely, Dan

    2016-04-01

    There is a paucity of methods for improving the affective experience of exercise. We tested a novel method based on discoveries about the relation between exercise intensity and pleasure, and lessons from behavioral economics. We examined the effect of reversing the slope of pleasure during exercise from negative to positive on pleasure and enjoyment, remembered pleasure, and forecasted pleasure. Forty-six adults were randomly assigned to a 15-min bout of recumbent cycling of either increasing intensity (0-120% of watts corresponding to the ventilatory threshold) or decreasing intensity (120-0%). Ramping intensity down, thereby eliciting a positive slope of pleasure during exercise, improved postexercise pleasure and enjoyment, remembered pleasure, and forecasted pleasure. The slope of pleasure accounted for 35-46% of the variance in remembered and forecasted pleasure from 15 min to 7 days postexercise. Ramping intensity down makes it possible to combine exposure to vigorous and moderate intensities with a pleasant affective experience.

  13. Effect of maximal-intensity exercise on systemic nitro-oxidative stress in men and women.

    Science.gov (United States)

    Wiecek, Magdalena; Maciejczyk, Marcin; Szymura, Jadwiga; Szygula, Zbigniew

    2017-07-01

    The aim of this study was to test the hypotheses: (1) there is a negative correlation between protein and lipid oxidative damage following maximal-intensity exercise, and oxygen uptake and work intensity (%VO2max) at the respiratory compensation point (RCP) in women and men; (2) nitro-oxidative stress following maximal-intensity exercise results from the intensification of anaerobic processes and muscle fibre micro-damage. Study participants comprised 20 women (21.34±1.57 years) and 20 men (21.97±1.41 years) who performed a treadmill incremental test (IT); VO2max: 45.08 ± 0.91 and 57.38 ± 1.22 mL kg-1 min-1 for women and men, respectively. The oxidized low-density lipoprotein (ox-LDL), 3-nitrotyrosine (3-NT) concentration and creatine kinase (CK) as well as lactate dehydrogenase (LDH) activity were measured in the blood serum, and total antioxidative capacity (TAC) and lactate concentration (Lac) were determined in blood plasma before and after IT. After the IT, increases in ox-LDL, 3-NT, CK, and LDH were seen in both groups (P women (P women. Only in the group of women was a positive correlation (P independent of VO2max, oxygen consumption and exercise intensity at RCP. This increase of ox-LDL and 3-NT is indicative of similar lipid and protein damage in women and men. A significant increase in TAC in women following maximal-intensity exercise is the result of muscle fibre micro-injuries.

  14. 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.

  15. Eccentric resistance training intensity may affect the severity of exercise induced muscle damage.

    Science.gov (United States)

    Hasenoehrl, Timothy; Wessner, Barbara; Tschan, Harald; Vidotto, Claudia; Crevenna, Richard; Csapo, Robert

    2017-09-01

    The aim of the present study was to assess the role of eccentric exercise intensity in the development of and recovery from delayed onset muscle soreness (DOMS). Using a cross-over study design, 15 healthy, male college students were tested on two occasions. The training stimulus consisted of an exhaustive series of eccentric muscle contractions of the elbow flexors at either 100% (high intensity) or 50% (low intensity) of the individual concentric one-repetition maximum. Blood samples were taken at baseline as well as 24, 48, 72 and 96 hours postexercise, and analyzed for creatine kinase, myoglobin, interleukin-6 and prostaglandin-2. Additionally, upper arm circumference (CIRC) and DOMS-related sensation of pain (PAIN) were measured. Following high intensity training, CIRC was significantly greater (P=0.007). Further, creatine kinase, myoglobin and interleukin-6 tended to be higher, although the main effect of the factor "intensity" just failed to reach significance (creatine kinase: P=0.056, myoglobin: P=0.064, interleukin-6: P=0.091). No differences were found for prostaglandin-2 (P=0.783) and PAIN (P=0.147). When performed at greater intensity, fatiguing eccentric resistance exercise of the elbow flexors leads to greater muscle swelling and, potentially, increases in serum markers reflecting lesions in the muscle's cellular membrane.

  16. Comparison of oxygen uptake during and after the execution of resistance exercises and exercises performed on ergometers, matched for intensity

    Directory of Open Access Journals (Sweden)

    Vilaça-Alves José

    2016-12-01

    Full Text Available The aim of this study was to compare the values of oxygen uptake (VO2 during and after strength training exercises (STe and ergometer exercises (Ee, matched for intensity and exercise time. Eight men (24 ± 2.33 years performed upper and lower body cycling Ee at the individual’s ventilatory threshold (VE/VCO2. The STe session included half squats and the bench press which were performed with a load at the individual blood lactate concentration of 4 mmol/l. Both sessions lasted 30 minutes, alternating 50 seconds of effort with a 10 second transition time between upper and lower body work. The averaged overall VO2 between sessions was significantly higher for Ee (24.96 ± 3.6 ml·kg·min-1 compared to STe (21.66 ± 1.77 ml·kg·min-1 (p = 0.035, but this difference was only seen for the first 20 minutes of exercise. Absolute VO2 values between sessions did not reveal differences. There were more statistically greater values in Ee compared to STe, regarding VO2 of lower limbs (25.44 ± 3.84 ml·kg·min-1 versus 21.83 ± 2·24 ml·kg·min-1; p = 0.038 and upper limbs (24.49 ± 3.84 ml·kg·min-1 versus 21.54 ± 1.77 ml·kg·min-1; p = 0.047. There were further significant differences regarding the moment effect (p<0.0001 of both STe and Ee sessions. With respect to the moment × session effect, only VO2 5 minutes into recovery showed significant differences (p = 0.017. In conclusion, although significant increases in VO2 were seen following Ee compared to STe, it appears that the load/intensity, and not the material/equipment used for the execution of an exercise, are variables that best influence oxygen uptake.

  17. Post-prandial carbohydrate ingestion during 1-h of moderate-intensity, intermittent cycling does not improve mood, perceived exertion, or subsequent power output in recreationally-active exercisers

    Directory of Open Access Journals (Sweden)

    O’Neal Eric K

    2013-01-01

    Full Text Available Abstract Background This study compared the effects of ingesting water (W, a flavored carbohydrate-electrolyte (CE or a flavored non-caloric electrolyte (NCE beverage on mood, ratings of perceived exertion (RPE, and sprint power during cycling in recreational exercisers. Methods Men (n = 23 and women (n = 13 consumed a 24–h standardized diet and reported 2–4 h post-prandial for all test sessions. After a familiarization session, participants completed 50 min of stationary cycling in a warm environment (wet bulb globe temperature = 25.0°C at ~ 60-65% of heart rate reserve (146 ± 4 bpm interspersed with 5 rest periods of 2 min each. During exercise, participants consumed W, CE, or NCE, served in a counterbalanced cross-over design. Beverage volume was served in 3 aliquots equaling each individual’s sweat losses (mean 847 ± 368 mL during the familiarization session. Profiles of Mood States questionnaires (POMS were administered and blood glucose levels were determined pre- and post- sub-maximal cycling. Following sub-maximal exercise, participants completed 3 30–s Wingate anaerobic tests (WAnT with 2.5 min rest between tests to assess performance. Results Blood glucose was higher (p AnT for CE (6.1 ± 1.7 mmol/L compared to W (4.9 ± 1.5 mmol/L and NCE (4.6 ± 1.2 mmol/L. Nonetheless, there were no differences among treatments in peak (642 ± 153, 635 ± 143, 650 ± 141 watts for W, NCE, and CE, respectively; p  =  0.44 or mean (455 ± 100, 458 ± 95, 454 ± 95 watts for W, NCE, and CE, respectively; p = 0.62 power for the first WAnT or mean (414 ± 92, 425 ± 85, 423 ± 82 watts, respectively; p = 0.13 power output averaged across all 3 WAnT. Likewise, RPE during submaximal exercise, session RPE, and fatigue and vigor assessed by POMS did not differ among beverage treatments (p > 0.05. Conclusions Carbohydrate ingestion consumed by recreational

  18. 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.

  19. 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

  20. 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.

  1. Tolerance to exercise intensity modulates pleasure when exercising in music: The upsides of acoustic energy for High Tolerant individuals.

    Directory of Open Access Journals (Sweden)

    Mauraine Carlier

    Full Text Available Moderate physical activity can be experienced by some as pleasurable and by others as discouraging. This may be why many people lack sufficient motivation to participate in the recommended 150 minutes of moderately intense exercise per week. In the present study, we assessed how pleasure and enjoyment were modulated differently by one's tolerance to self-paced physical activity. Sixty-three healthy individuals were allocated to three independent experimental conditions: a resting condition (watching TV, a cycling in silence condition, and a cycling in music condition. The tolerance threshold was assessed using the PRETIE-Questionnaire. Physical activity consisted in cycling during 30 minutes, at an intensity perceived as "somewhat difficult" on the Ratings of Perceived Exertion Scale. While controlling for self-reported physical activity level, results revealed that for the same perception of exertion and a similar level of enjoyment, the High Tolerance group produced more power output than the Low Tolerance group. There was a positive effect of music for High Tolerant individuals only, with music inducing greater power output and more pleasure. There was an effect of music on heart rate frequency in the Low Tolerant individuals without benefits in power output or pleasure. Our results suggest that for Low Tolerant individuals, energizing environments can interfere with the promised (positive distracting effects of music. Hence, tolerance to physical effort must be taken into account to conceive training sessions that seek to use distracting methods as means to sustain pleasurable exercising over time.

  2. Tolerance to exercise intensity modulates pleasure when exercising in music: The upsides of acoustic energy for High Tolerant individuals.

    Science.gov (United States)

    Carlier, Mauraine; Delevoye-Turrell, Yvonne

    2017-01-01

    Moderate physical activity can be experienced by some as pleasurable and by others as discouraging. This may be why many people lack sufficient motivation to participate in the recommended 150 minutes of moderately intense exercise per week. In the present study, we assessed how pleasure and enjoyment were modulated differently by one's tolerance to self-paced physical activity. Sixty-three healthy individuals were allocated to three independent experimental conditions: a resting condition (watching TV), a cycling in silence condition, and a cycling in music condition. The tolerance threshold was assessed using the PRETIE-Questionnaire. Physical activity consisted in cycling during 30 minutes, at an intensity perceived as "somewhat difficult" on the Ratings of Perceived Exertion Scale. While controlling for self-reported physical activity level, results revealed that for the same perception of exertion and a similar level of enjoyment, the High Tolerance group produced more power output than the Low Tolerance group. There was a positive effect of music for High Tolerant individuals only, with music inducing greater power output and more pleasure. There was an effect of music on heart rate frequency in the Low Tolerant individuals without benefits in power output or pleasure. Our results suggest that for Low Tolerant individuals, energizing environments can interfere with the promised (positive) distracting effects of music. Hence, tolerance to physical effort must be taken into account to conceive training sessions that seek to use distracting methods as means to sustain pleasurable exercising over time.

  3. Moderate-to-high intensity physical exercise in patients with Alzheimer’s disease

    DEFF Research Database (Denmark)

    Hoffmann, Kristine; Sobol, Nanna A.; Frederiksen, Kristian S.

    2016-01-01

    Background: Studies of physical exercise in patients with Alzheimer’s disease (AD) are few and results have been inconsistent. Objective: To assess the effects of a moderate-to-high intensity aerobic exercise program in patients with mild AD. Methods: In a randomized controlled trial, we recruited...... 200 patients with mild AD to a supervised exercise group (60-min sessions three times a week for 16 weeks) or to a control group. Primary outcome was changed from baseline in cognitive performance estimated by Symbol Digit Modalities Test (SDMT) in the intention-to-treat (ITT) group. Secondary...... outcomes included changes in quality of life, ability to perform activities of daily living, and in neuropsychiatric and depressive symptoms. Results: The ITT analysis showed no significant differences between intervention and control groups in change from baseline of SDMT, other cognitive tests, quality...

  4. A motivational music and video intervention improves high-intensity exercise performance.

    Science.gov (United States)

    Barwood, Martin J; Weston, Neil J V; Thelwell, Richard; Page, Jennifer

    2009-01-01

    Music and video are utilised by recreational gym users to enhance their exercise experience. Music and video have not been investigated for their combined ergogenic effect during high intensity exercise. To induce fatigue, this study was performed in warm (~26°C), moist conditions (~50%RH). Six, non-acclimated, male participants took part in the study. Each participant completed three 30-minute exercise bouts on a motorised treadmill under three counterbalanced conditions on separate days: control (CON), motivational music plus video intervention (M), non-motivational intervention (NM). They completed a warm-up (5 km·h(-1) [5 minutes], 9km·h(-1) [10 minutes]) followed by a maximal effort run (15 minutes). Participants did not receive any feedback of time elapsed, distance run or speed. Distance covered (metres), heart rate, blood lactate accumulation (B(lac)) and ratings of perceived exertion (RPE). Participants in the M condition ran significantly further than in the NM (M: 3524 [388]metres; NM: 3110 [561]metres; CON: 3273 [458]metres) and CON conditions, accumulated more B(lac), but did not increase their peak RPE rating (p music and video) may have facilitated this improvement. These findings have strong implications for improving health, fitness and engagement in gym-based exercise programs. Key pointsThe study examined the ergogenic effect of a motivational (M) video and music intervention on high-intensity exercise performance in comparison to a non-motivational (NM) condition and a control (CON).PARTICIPANTS IN THE M CONDITION RAN SIGNIFICANTLY FURTHER THAN IN THE NM (M: 3524 [388]metres; NM: 3110 [561]metres; CON: 3273 [458]metres) and CON conditions, accumulated more B(lac), but did not increase their peak RPE rating (p music and video) may have facilitated this improvement.These findings have strong implications for improving health, fitness and engagement in gym-based exercise programs.

  5. Preferred intensity exercise for adolescents receiving treatment for depression: a pragmatic randomised controlled trial.

    Science.gov (United States)

    Carter, Tim; Guo, Boliang; Turner, David; Morres, Ioannis; Khalil, Elizabeth; Brighton, Emily; Armstrong, Marie; Callaghan, Patrick

    2015-10-14

    Exercise has been shown to be effective in treating depression, but trials testing the effect of exercise for depressed adolescents utilising mental health services are rare. The aim of this study was to determine the effectiveness of a preferred intensity exercise intervention on the depressive symptoms of adolescents with depression. We randomly assigned 87 adolescents who were receiving treatment for depression to either 12 sessions of aerobic exercise at preferred intensity alongside treatment as usual or treatment as usual only. The primary outcome was depressive symptom change using the Children's Depression Inventory 2(nd) Version (CDI-2) at post intervention. Secondary outcomes were health-related quality of life and physical activity rates. Outcomes were taken at baseline, post intervention and at six month follow up. CDI-2 score reduction did not differ significantly between groups at post-intervention (est. 95% CI -6.82, 1.68, p = 0.23). However, there was a difference in CDI-2 score reduction at six month follow-up in favour of the intervention of -4.81 (est. 95% CI -9.49, -0.12, p = 0.03). Health-related quality of life and physical activity rates did not differ significantly between groups at post-intervention and follow-up. There was no additional effect of preferred intensity exercise alongside treatment as usual on depressive reduction immediately post intervention. However, effects were observed at six months post-intervention, suggesting a delayed response. However, further trials, with larger samples are required to determine the validity of this finding. ClinicalTrials.gov NCT01474837, March 16 2011.

  6. 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....

  7. Perspectives on high-intensity interval exercise for health promotion in children and adolescents

    Directory of Open Access Journals (Sweden)

    Bond B

    2017-11-01

    Full Text Available Bert Bond,1 Kathryn L Weston,2 Craig A Williams,1 Alan R Barker1 1Children’s Health and Exercise Research Centre, Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK 2School of Health and Social Care, Teesside University, Middlesbrough, UK Abstract: Physical activity lowers future cardiovascular disease (CVD risk; however, few children and adolescents achieve the recommended minimum amount of daily activity. Accordingly, there is virtue in identifying the efficacy of small volumes of high-intensity exercise for health benefits in children and adolescents for the primary prevention of CVD risk. The purpose of this narrative review is to provide a novel overview of the available literature concerning high-intensity interval-exercise (HIIE interventions in children and adolescents. Specifically, the following areas are addressed: 1 outlining the health benefits observed following a single bout of HIIE, 2 reviewing the role of HIIE training in the management of pediatric obesity, and 3 discussing the effectiveness of school-based HIIE training. In total, 39 HIIE intervention studies were included in this review. Based upon the available data, a single bout of high-intensity exercise provides a potent stimulus for favorable, acute changes across a range of cardiometabolic outcomes that are often superior to a comparative bout of moderate-intensity exercise (14 studies reviewed. HIIE also promotes improvements in cardiorespiratory fitness and cardiometabolic health status in overweight and obese children and adolescents (10 studies reviewed and when delivered in the school setting (15 studies reviewed. We thus conclude that high-intensity exercise is a feasible and potent method of improving a range of cardiometabolic outcomes in children and adolescents. However, further work is needed to optimize the delivery of HIIE interventions in terms of participant enjoyment and acceptability, to include a

  8. 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.

  9. High-intensity interval exercise improves vagal tone and decreases arrhythmias in chronic heart failure.

    Science.gov (United States)

    Guiraud, Thibaut; Labrunee, Marc; Gaucher-Cazalis, Kevin; Despas, Fabien; Meyer, Philippe; Bosquet, Laurent; Gales, Celine; Vaccaro, Angelica; Bousquet, Marc; Galinier, Michel; Sénard, Jean-Michel; Pathak, Atul

    2013-10-01

    Autonomic dysfunction including sympathetic activation and vagal withdrawal has been reported in patients with chronic heart failure (CHF). We tested the hypotheses that high-intensity interval exercise (HIIE) in CHF patients would enhance vagal modulation and thus decrease arrhythmic events. Eighteen CHF patients underwent a baseline assessment (CON) and were then randomized to a single session of HIIE and to an isocaloric moderate-intensity continuous exercise (MICE). We evaluated the HR, HR variability parameters, and arrhythmic events by 24-h Holter ECG recordings after HIIE, MICE, and CON sessions. We found that HR was significantly decreased after HIIE (68 ± 3 bpm, P CHF patients, leading to significant reductions of HR and arrhythmic events in a 24-h posttraining period. Cardioprotective effects of HIIE in CHF patients need to be confirmed in a larger study population and on a long-term basis.

  10. Influence of music on performance and psychophysiological responses during moderate-intensity exercise preceded by fatigue.

    Science.gov (United States)

    Lopes-Silva, Joao P; Lima-Silva, Adriano E; Bertuzzi, Romulo; Silva-Cavalcante, Marcos D

    2015-02-01

    We examined the effects of listening to music on time to exhaustion and psychophysiological responses during moderate-intensity exercise performed in fatigued and non-fatigued conditions. Fourteen healthy men performed moderate-intensity exercise (60% Wmax) until exhaustion under four different conditions: with and without pre-fatigue (induced by 100 drop jumps) and listening and not listening to music. Time to exhaustion was lower in the fatigued than the non-fatigued condition regardless listening to music. Similarly, RPE was higher in the fatigued than the non-fatigued condition, but music had no effect. On the other hand, listening to music decreased the associative thoughts regardless of fatigue status. Heart rate was not influenced by any treatment. These results suggest that listening to music changes attentional focus but is not able to reverse fatigue-derived alteration of performance. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. An intensive exercise program improves motor performances in patients with dementia: translational model of geriatric rehabilitation.

    Science.gov (United States)

    Schwenk, Michael; Dutzi, Ilona; Englert, Stefan; Micol, William; Najafi, Bijan; Mohler, Jane; Hauer, Klaus

    2014-01-01

    Translation of intensive exercise programs developed specifically for patients with dementia into clinical settings is lacking. To determine if a progressive resistance and functional training program, previously evaluated in dementia outpatients, can be implemented in a geriatric inpatient setting in order to improve motor performances in patients with dementia. Eligible patients in one ward of a German geriatric hospital were assigned to the intervention group (IG, n = 74) and received intensive exercise training specifically designed for patients with dementia. Patients in the second ward were observed as a control group (CG, n = 74). All patients received usual care treatment. Primary endpoints were maximal lower extremity strength measured by a leg-press device and duration of the 5-chair-stand test for functional performance. Secondary outcomes included a number of parameters for strength and function. The rehabilitation period averaged 18.1 ± 6.8 days. The IG significantly improved in both primary endpoints (change: maximal strength, IG: +51.9 ± 42.3% versus CG: +13.5 ± 51.8%, p exercise program can be implemented in a geriatric rehabilitation setting to improve motor performances in patients with dementia. Results suggest that an intensification of training is feasible in the target group and substantially increases the benefits in comparison to receiving usual care exercise only.

  12. Effects of exercise intensity on spatial memory performance and hippocampal synaptic plasticity in transient brain ischemic rats.

    Science.gov (United States)

    Shih, Pei-Cheng; Yang, Yea-Ru; Wang, Ray-Yau

    2013-01-01

    Memory impairment is commonly noted in stroke survivors, and can lead to delay of functional recovery. Exercise has been proved to improve memory in adult healthy subjects. Such beneficial effects are often suggested to relate to hippocampal synaptic plasticity, which is important for memory processing. Previous evidence showed that in normal rats, low intensity exercise can improve synaptic plasticity better than high intensity exercise. However, the effects of exercise intensities on hippocampal synaptic plasticity and spatial memory after brain ischemia remain unclear. In this study, we investigated such effects in brain ischemic rats. The middle cerebral artery occlusion (MCAO) procedure was used to induce brain ischemia. After the MCAO procedure, rats were randomly assigned to sedentary (Sed), low-intensity exercise (Low-Ex), or high-intensity exercise (High-Ex) group. Treadmill training began from the second day post MCAO procedure, 30 min/day for 14 consecutive days for the exercise groups. The Low-Ex group was trained at the speed of 8 m/min, while the High-Ex group at the speed of 20 m/min. The spatial memory, hippocampal brain-derived neurotrophic factor (BDNF), synapsin-I, postsynaptic density protein 95 (PSD-95), and dendritic structures were examined to document the effects. Serum corticosterone level was also quantified as stress marker. Our results showed the Low-Ex group, but not the High-Ex group, demonstrated better spatial memory performance than the Sed group. Dendritic complexity and the levels of BDNF and PSD-95 increased significantly only in the Low-Ex group as compared with the Sed group in bilateral hippocampus. Notably, increased level of corticosterone was found in the High-Ex group, implicating higher stress response. In conclusion, after brain ischemia, low intensity exercise may result in better synaptic plasticity and spatial memory performance than high intensity exercise; therefore, the intensity is suggested to be considered

  13. Effects of exercise intensity on spatial memory performance and hippocampal synaptic plasticity in transient brain ischemic rats.

    Directory of Open Access Journals (Sweden)

    Pei-Cheng Shih

    Full Text Available Memory impairment is commonly noted in stroke survivors, and can lead to delay of functional recovery. Exercise has been proved to improve memory in adult healthy subjects. Such beneficial effects are often suggested to relate to hippocampal synaptic plasticity, which is important for memory processing. Previous evidence showed that in normal rats, low intensity exercise can improve synaptic plasticity better than high intensity exercise. However, the effects of exercise intensities on hippocampal synaptic plasticity and spatial memory after brain ischemia remain unclear. In this study, we investigated such effects in brain ischemic rats. The middle cerebral artery occlusion (MCAO procedure was used to induce brain ischemia. After the MCAO procedure, rats were randomly assigned to sedentary (Sed, low-intensity exercise (Low-Ex, or high-intensity exercise (High-Ex group. Treadmill training began from the second day post MCAO procedure, 30 min/day for 14 consecutive days for the exercise groups. The Low-Ex group was trained at the speed of 8 m/min, while the High-Ex group at the speed of 20 m/min. The spatial memory, hippocampal brain-derived neurotrophic factor (BDNF, synapsin-I, postsynaptic density protein 95 (PSD-95, and dendritic structures were examined to document the effects. Serum corticosterone level was also quantified as stress marker. Our results showed the Low-Ex group, but not the High-Ex group, demonstrated better spatial memory performance than the Sed group. Dendritic complexity and the levels of BDNF and PSD-95 increased significantly only in the Low-Ex group as compared with the Sed group in bilateral hippocampus. Notably, increased level of corticosterone was found in the High-Ex group, implicating higher stress response. In conclusion, after brain ischemia, low intensity exercise may result in better synaptic plasticity and spatial memory performance than high intensity exercise; therefore, the intensity is suggested to be

  14. Effects of Aerobic Exercise Programme with Different Intensities on Blood Pressure and Low Density Lipoproteins

    OpenAIRE

    Dr. Ajayakumar Koorma

    2017-01-01

    The purpose of the present study was to find out the effect of aerobic exercise programme with different intensities on blood pressure and low density lipoproteins among middle aged women. For this purpose, thirty middle aged women residing at various places around Kannur Town, Kerala, were selected as subjects. The age of the subjects were ranged from 35 to 45 years. They were divided into three equal groups, each group consisted of ten subjects, in which experimental group - I underwent aer...

  15. Urine concentrations of oral salbutamol in samples collected after intense exercise in endurance athletes

    DEFF Research Database (Denmark)

    Hostrup, Morten; Kalsen, Anders; Auchenberg, Michael

    2014-01-01

    Our objective was to investigate urine concentrations of 8 mg oral salbutamol in samples collected after intense exercise in endurance athletes. Nine male endurance athletes with a VO2max of 70.2 ± 5.9 mL/min/kg (mean ± SD) took part in the study. Two hours after administration of 8 mg oral...

  16. Enhancing energy expenditure and enjoyment of exercise during pregnancy through the addition of brief higher intensity intervals to traditional continuous moderate intensity cycling.

    Science.gov (United States)

    Ong, Ming Jing; Wallman, Karen E; Fournier, Paul A; Newnham, John P; Guelfi, Kym J

    2016-07-15

    Current guidelines recommend that pregnant women without contraindications should engage in 30 min or more of moderate intensity exercise on most days of the week, however, many women fail to achieve this goal. This study examined the effect of adding brief higher intensity intervals to traditional continuous moderate intensity exercise on energy expenditure and the enjoyment of exercise in late pregnancy. This is important to determine given that any additional energy expenditure resulting from higher intensity intervals may be meaningless if enjoyment is compromised, since long-term adherence will likely be low. In this study, 12 healthy pregnant women at 30 ± 1 weeks gestation, aged 35 ± 6 years with a BMI of 27.1 ± 4.3 kg/m(2) performed either 30 min of continuous cycling exercise (CONT) at a steady power output equivalent to 65 % age-predicted heart rate maximum or an equivalent period of interval cycling (INTV) consisting of continuous cycling at the same power output as CONT, but with the addition of six 15-s self-paced higher intensity efforts throughout, performed at regular intervals, on separate occasions in a counterbalanced order. Mean cycling power output, heart rate, oxygen consumption and energy expenditure were higher during INTV compared with CONT (P exercise was higher with INTV (P = 0.01). The addition of six 15-s higher intensity intervals to continuous moderate intensity exercise effectively increased energy expenditure by 28 %, at the same time as enhancing the enjoyment of exercise in late pregnancy. While these findings may be specific to recreationally active women, this study provides a rationale for future studies to examine the physiological and psychological responses to regular interval training during pregnancy to optimise exercise prescription. Australian New Zealand Clinical Trials Registry ACTRN12616000680460 . 25 May 2016 (Registered retrospectively).

  17. Energy replacement using glucose does not increase postprandial lipemia after moderate intensity exercise.

    Science.gov (United States)

    Chiu, Chih-Hui; Burns, Stephen Francis; Yang, Tsung-Jen; Chang, Yi-Hsin; Chen, Yi-Liang; Chang, Cheng-Kang; Wu, Ching-Lin

    2014-11-25

    Aerobic exercise can decrease postprandial triglyceride (TG) concentrations but the relationship between exercise-induced energy deficits and postprandial lipemia is still unclear. The aim of the present study was to examine the effect of a single bout of aerobic exercise, with and without energy replacement, on postprandial lipemia and on peripheral blood mononuclear cell (PBMC) mRNA expression of very low density lipoprotein (VLDL) and low density lipoprotein (LDL) receptors and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR). Nine healthy male humans completed three two-day trials in a random order. On day 1, volunteers rested (CON), completed 60 minutes of treadmill walking at 50% of VO2peak (EX) or completed the same bout of walking but with the energy replaced afterwards with a glucose solution (EXG). On day 2, volunteers rested and consumed a high fat test meal in the morning. Total and incremental TG AUC were significantly lower on the EXG (P  0.05). In conclusion, energy replacement by glucose did not affect the decrease in postprandial TG concentrations observed after moderate intensity exercise and exercise does not affect changes in PBMC HMGCR, VLDL and LDL receptor mRNA expression.

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

    Science.gov (United States)

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

    2013-08-01

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

  19. Prior intense exercise reduces arterial carbon dioxide pressure in extreme obesity.

    Science.gov (United States)

    Zavorsky, Gerald S; Kim, Do Jun; Cass, Lauren M; Carli, Franco

    2010-10-01

    Unlike normal weight individuals, individuals with extreme obesity do not show a decrease in arterial carbon dioxide pressure (PaCO₂) from rest to peak exercise. This indicates that breathing is compromised. The objective of this study was to determine if prior high intensity exercise lowers PaCO₂ in comparison with a first bout, normalized for the same metabolic rate. Oxygen consumption during incremental, ramped exercise was matched to constant workload exercise (75% of peak power). Both protocols were to volitional exhaustion 39 ± 8 min apart. Eleven obese subjects (BMI = 47 ± 8 kg/m², aerobic capacity = 2.3 ± 0.6 L/min) were evaluated. Forty paired samples were obtained at the same metabolic rate between the two protocols. The mean absolute difference and 95% CI were large for arterial oxygen pressure (PaO₂) = 9 (6, 11) mmHg and alveolar to arterial oxygen pressure difference (AaDO2) = 7 (5, 8) mmHg. The mean absolute difference for arterial oxyhemoglobin saturation (%SaO₂) = 0.5 (0.4, 0.7) %; PaCO2 = 4 (3, 4) mmHg; physiological dead space to tidal volume ratio (VD/VT) = 0.04 (0.03, 0.05); and alveolar ventilation (VA) = 3 (2, 4) L/min. The recovery period after the first bout of exercise reduced the PaCO₂ by 3 mmHg when matched for similar metabolic rates. Constant workload exercise predicted VA, %SaO2, V(D)/V(T), and PaCO₂, but not PaO₂ or AaDO₂ during incremental exercise at similar metabolic rates. Given a sufficient chemical stimulus, obese subjects will attempt to breathe more, although this does not mean more VA, which removes CO₂.

  20. Effects of an acute bout of moderate-intensity exercise on postprandial lipemia and airway inflammation.

    Science.gov (United States)

    Johnson, Ariel M; Kurti, Stephanie P; Smith, Joshua R; Rosenkranz, Sara K; Harms, Craig A

    2016-03-01

    A high-fat meal (HFM) induces an increase in blood lipids (postprandial lipemia; PPL), systemic inflammation, and acute airway inflammation. While acute exercise has been shown to have anti-inflammatory and lipid-lowering effects, it is unknown whether exercise prior to an HFM will translate to reduced airway inflammation post-HFM. Our purpose was to determine the effects of an acute bout of exercise on airway inflammation post-HFM and to identify whether any protective effect of exercise on airway inflammation was associated with a reduction in PPL or systemic inflammation. In a randomized cross-over study, 12 healthy, 18- to 29-year-old men (age, 23.0 ± 3.2 years; height, 178.9 ± 5.5 cm; weight, 78.5 ± 11.7 kg) consumed an HFM (1 g fat/1 kg body weight) 12 h following exercise (EX; 60 min at 60% maximal oxygen uptake) or without exercise (CON). Fractional exhaled nitric oxide (FENO; measure of airway inflammation), triglycerides (TG), and inflammatory markers (high-sensitivity C-reactive protein, tumor-necrosis factor-alpha, and interleukin-6) were measured while fasted at 2 h and 4 h post-HFM. FENO increased over time (2 h: CON, p = 0.001; EX, p = 0.002, but not by condition (p = 0.991). TG significantly increased 2 and 4 h post-HFM (p 0.05). There were no relationships between FENO and TG or systemic inflammatory markers for any time point or condition (p > 0.05). In summary, an acute bout of moderate-intensity exercise performed 12 h prior to an HFM did not change postprandial airway inflammation or lipemia in healthy, 18- to 29-year-old men.

  1. Obese but not lean adolescents spontaneously decrease energy intake after intensive exercise.

    Science.gov (United States)

    Thivel, David; Metz, Lore; Julien, Aucouturier; Morio, Béatrice; Duché, Pascale

    2014-01-17

    Acute intensive exercise has been shown to induce a decreased subsequent daily energy intake in obese adolescents without altering the subjective appetite feelings. It is however unclear whether or not those nutritional adaptations to acute exercise are affected by the adolescents' weight status. The aim of this study was to compare the energy intake and macronutrient preferences, appetite feeling and energy expenditure response to acute exercise between lean and obese adolescents. Ten obese and nine normal weight 12-15year old adolescents randomly completed a session with a 30minute cycling exercise at 75% VO2max and a sedentary session. During both sessions energy expenditure was assessed using Armband, ad libitum energy intake measured by weighing at both lunch and dinner time and appetite feelings assessed using visual analog scales. Daily, morning and afternoon energy expenditure were significantly higher in obese than in normal weight adolescents (penergy expenditure was significantly higher during EX (1086±157kcal) compared to SED (853±154kcal) in lean (pobese (respectively 1865±222 and 1803±232kcal). Afternoon energy expenditure was significantly lower during EX compare to SED in obese (penergy intake were significantly reduced after the exercise session in obese (p>0.05) but not in lean adolescents. No group or condition effects were observed on subjective appetite feelings. Post exercise spontaneous energy intake and energy expenditure are reduced in obese but not in normal weight adolescents, without appetite feeling changes. Acute exercise may have a greater impact on energy balance through the induced decreased energy intake in the absence of significant change in energy expenditure in obese youth. © 2013 Elsevier Inc. All rights reserved.

  2. Hippocampal-Brainstem Connectivity Associated with Vagal Modulation after an Intense Exercise Intervention in Healthy Men

    Science.gov (United States)

    Bär, Karl-Jürgen; Herbsleb, Marco; Schumann, Andy; de la Cruz, Feliberto; Gabriel, Holger W.; Wagner, Gerd

    2016-01-01

    Regular physical exercise leads to increased vagal modulation of the cardiovascular system. A combination of peripheral and central processes has been proposed to underlie this adaptation. However, specific changes in the central autonomic network have not been described in human in more detail. We hypothesized that the anterior hippocampus known to be influenced by regular physical activity might be involved in the development of increased vagal modulation after a 6 weeks high intensity intervention in young healthy men (exercise group: n = 17, control group: n = 17). In addition to the determination of physical capacity before and after the intervention, we used resting state functional magnetic resonance imaging and simultaneous heart rate variability assessment. We detected a significant increase of the power output at the anaerobic threshold of 11.4% (p exercise group (EG). Comparing baseline (T0) and post-exercise (T1) values of parasympathetic modulation of the exercise group, we observed a trend for a decrease in heart rate (p brain analysis, we found that the connectivity pattern of the right anterior hippocampus (aHC) was specifically altered to the ventromedial anterior cortex, the dorsal striatum and to the dorsal vagal complex (DVC) in the brainstem. Moreover, we observed a highly significant negative correlation between increased RMSSD after exercise and decreased functional connectivity from the right aHC to DVC (r = −0.69, p = 0.003). This indicates that increased vagal modulation was associated with functional connectivity between aHC and the DVC. In conclusion, our findings suggest that exercise associated changes in anterior hippocampal function might be involved in increased vagal modulation. PMID:27092046

  3. Effect of β-alanine supplementation on high-intensity exercise performance.

    Science.gov (United States)

    Harris, Roger C; Stellingwerff, Trent

    2013-01-01

    Carnosine is a dipeptide of β-alanine and L-histidine found in high concentrations in skeletal muscle. Combined with β-alanine, the pKa of the histidine imidazole ring is raised to ∼6.8, placing it within the muscle intracellular pH high-intensity exercise transit range. Combination with β-alanine renders the dipeptide inert to intracellular enzymic hydrolysis and blocks the histidinyl residue from participation in proteogenesis, thus making it an ideal, stable intracellular buffer. For vegetarians, synthesis is limited by β-alanine availability; for meat-eaters, hepatic synthesis is supplemented with β-alanine from the hydrolysis of dietary carnosine. Direct oral β-alanine supplementation will compensate for low meat and fish intake, significantly raising the muscle carnosine concentration. This is best achieved with a sustained-release formulation of β-alanine to avoid paresthesia symptoms and decreasing urinary spillover. In humans, increased levels of carnosine through β-alanine supplementation have been shown to increase exercise capacity and performance of several types, particularly where the high-intensity exercise range is 1-4 min. β-Alanine supplementation is used by athletes competing in high-intensity track and field cycling, rowing, swimming events and other competitions. Copyright © 2013 Nestec Ltd., Vevey/S. Karger AG, Basel.

  4. Exercise intensity and gender difference of 3 different salsa dancing conditions.

    Science.gov (United States)

    Emerenziani, G P; Guidetti, L; Gallotta, M C; Franciosi, E; Buzzachera, C F; Baldari, C

    2013-04-01

    The aims of this study were to estimate the difference in exercise intensity (METs), energy cost (EE) and gender difference between a typical salsa lesson (TSL), rueda de casino lesson (RCL), and salsa dancing at a night club (SDN). Subjects performed 1 pre-testing session and 3 testing conditions. During the pre-testing session height, weight and V˙O2max were assessed. During the testing conditions all subjects performed 3 different kinds of salsa dance. Heart rate was assessed during each dance condition. The exercise intensity of the 3 salsa dancing conditions was moderate ranging from 3.9 to 5.5 METs. A significant difference between genders for HRpeak (P=0.01), max%HRR (P=0.006) and mean EE (P=0.02) were observed. Significant gender×condition interactions for HRpeak (P=0.03), mean %HRR (P=0.02), mean METs (P=0.02) and mean EE (P=0.02) were found. In addition, a significant main effect for each condition was found in all variables (Pdancing conditions were moderate. Findings showed some significant differences in exercise intensity between males and females and within conditions. Salsa dancing could be useful in achieving a significant training effect in people who have a low level of fitness. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Patients with classic congenital adrenal hyperplasia have decreased epinephrine reserve and defective glycemic control during prolonged moderate-intensity exercise.

    Science.gov (United States)

    Green-Golan, Liza; Yates, Catherine; Drinkard, Bart; VanRyzin, Carol; Eisenhofer, Graeme; Weise, Martina; Merke, Deborah P

    2007-08-01

    Patients with classic congenital adrenal hyperplasia (CAH) have adrenomedullary dysplasia and hypofunction, and their lack of adrenomedullary reserve has been associated with a defective glucose response to brief high-intensity exercise. Our objective was to assess hormonal, metabolic, and cardiovascular response to prolonged moderate-intensity exercise comparable to brisk walking in adolescents with classic CAH. We compared six adolescents with classic CAH (16-20 yr old) with seven age-, sex-, and body mass index group-matched controls (16-23 yr old) using a 90-min standardized ergometer test. Metabolic, hormonal, and cardiovascular parameters were studied during exercise and recovery. Glucose did not change throughout exercise and recovery for controls, whereas CAH patients showed a steady decline in glucose during exercise with an increase in glucose in the postexercise period. Glucose levels were significantly lower in CAH patients at 60 (P = 0.04), 75 (P = 0.01), and 90 (P = 0.03) min of exercise and 15 (P = 0.02) min post exercise, whereas glucose levels were comparable between the two groups early in exercise and at 30 min (P = 0.19) post exercise. As compared with controls, CAH patients had significantly lower epinephrine (P = 0.002) and cortisol (P moderate-intensity exercise comparable to brisk walking.

  6. Effect of exercise intensity on postprandial lipemia, markers of oxidative stress, and endothelial function after a high-fat meal.

    Science.gov (United States)

    Lopes Krüger, Renata; Costa Teixeira, Bruno; Boufleur Farinha, Juliano; Cauduro Oliveira Macedo, Rodrigo; Pinto Boeno, Francesco; Rech, Anderson; Lopez, Pedro; Silveira Pinto, Ronei; Reischak-Oliveira, Alvaro

    2016-12-01

    The aim of this study was to compare the effects of 2 different exercise intensities on postprandial lipemia, oxidative stress markers, and endothelial function after a high-fat meal (HFM). Eleven young men completed 2-day trials in 3 conditions: rest, moderate-intensity exercise (MI-Exercise) and heavy-intensity exercise (HI-Exercise). Subjects performed an exercise bout or no exercise (Rest) on the evening of day 1. On the morning of day 2, an HFM was provided. Blood was sampled at fasting (0 h) and every hour from 1 to 5 h during the postprandial period for triacylglycerol (TAG), thiobarbituric acid reactive substance (TBARS), and nitrite/nitrate (NOx) concentrations. Flow-mediated dilatation (FMD) was also analyzed. TAG concentrations were reduced in exercise conditions compared with Rest during the postprandial period (P lipemia after an HFM. However, HI-Exercise showed to be more effective in reducing iAUC TAG, which might suggest higher protection against postprandial TAG enhancement. Conversely, MI-Exercise can be beneficial to attenuate the susceptibility of oxidative damage induced by an HFM and to increase endothelial function in the fasted state compared with Rest.

  7. [High versus moderate intense running exercise - effects on cardiometabolic risk-factors in untrained males].

    Science.gov (United States)

    Kemmler, Wolfgang; Lell, M; Scharf, M; Fraunberger, L; von Stengel, S

    2015-01-01

    Introduction | The philosophy on how to improve cardiometabolic risk factors most efficiently by endurance exercise is still controversial. To determine the effect of high-intensity (interval) training (HI[I]T) vs. moderate-intensity continuous exercise (MICE) training on cardiometabolic risk factors we conducted a 16-week crossover randomized controlled trial. Methods | 81 healthy untrained middle aged men were randomly assigned to a HI(I)T-group and a control-group that started the MICE running program after their control status. HI(I)T consisted of running exercise around or above the individual anaerobic threshold (≈ 80- 100 % HRmax); MICE focused on continuous running exercise at ≈ 65-77.5 % HRmax. Both protocols were comparable with respect to energy consumption. Study endpoints were cardiorespiratory fitness (VO2max), left ventricular mass index (LVMI), metabolic syndrome Z-score (MetS-Z-score), intima-media-thickness (IMT) and body composition. Results | VO2max-changes in this overweighed male cohort significantly (p=0.002) differ between HIIT (14.7 ± 9.3 %, p=0.001) and MICE (7.9 ± 7.4 %,p=0.001). LVMI, as determined via magnetic resonance imaging, significantly increased in both exercise groups (HIIT: 8.5 ± 5.4 %, p=0.001 vs. MICE: 5.3 ± 4.0 %, p=0.001), however the change was significantly more pronounced (p=0.005) in the HIIT-group. MetS-Z-score (HIIT: -2.06 ± 1.31, p=0.001 vs. MICE: -1.60 ± 1.77, p=0.001) and IMT (4.6 ± 5.9 % p=0.011 vs. 4.4 ± 8.1 %, p=0.019) did not show significant group-differences. Reductions of fat mass (-4.9 ± 9.0 %, p=0.010 vs. -9.5 ± 9.4, p=0.001) were significantly higher among the MICE-participants (p=0.034), however, the same was true (p=0.008) for lean body mass (0.5 ± 2.3 %, p=0.381 vs. -1.3 ± 2.0 %, p=0.003). Conclusion | In summary high-intensity interval training tends to impact cardiometabolic health more favorable compared with a moderate-intensity continuous endurance exercise protocol.

  8. Effects of inspiratory muscle training upon recovery time during high intensity, repetitive sprint activity.

    Science.gov (United States)

    Romer, L M; McConnell, A K; Jones, D A

    2002-07-01

    The present study examined the influence of specific inspiratory muscle training (IMT) upon recovery time during repetitive sprint activity, as well as the physiological and perceptual responses to fixed intensity shuttle running. Using a double-blind placebo-controlled design, 24 male repetitive sprint athletes were assigned randomly to either an IMT (n = 12) or placebo (n = 12) group. The self-selected recovery time during a repetitive sprint test and the physiological response to submaximal endurance exercise were determined. Following completion of baseline and pre-intervention measures, the IMT group performed 30 inspiratory efforts twice daily against a resistance equivalent to 50 % maximum inspiratory mouth pressure (MIP) for 6 wk. The placebo group performed 60 breaths once daily, for 6 wk, at a resistance equivalent to 15 % MIP, a load known to elicit negligible changes in respiratory muscle function. The IMT group improved total recovery time during the repetitive sprint test by 6.2 +/- 1.1 % (mean +/- SEM) above the changes noted for the placebo group (p = 0.006). Blood lactate and perceptual responses to submaximal exercise were also significantly attenuated following IMT (p lactate and perceptual responses to submaximal endurance exercise. In addition, the present study provides new evidence that IMT improves recovery time during high intensity, intermittent exercise in repetitive sprint athletes.

  9. Reliability of a Novel High Intensity One Leg Dynamic Exercise Protocol to Measure Muscle Endurance.

    Directory of Open Access Journals (Sweden)

    Benjamin Pageaux

    Full Text Available We recently developed a high intensity one leg dynamic exercise (OLDE protocol to measure muscle endurance and investigate the central and peripheral mechanisms of muscle fatigue. The aims of the present study were to establish the reliability of this novel protocol and describe the isokinetic muscle fatigue induced by high intensity OLDE and its recovery. Eight subjects performed the OLDE protocol (time to exhaustion test of the right leg at 85% of peak power output three times over a week period. Isokinetic maximal voluntary contraction torque at 60 (MVC60, 100 (MVC100 and 140 (MVC140 deg/s was measured pre-exercise, shortly after exhaustion (13 ± 4 s, 20 s (P20 and 40 s (P40 post-exercise. Electromyographic (EMG signal was analyzed via the root mean square (RMS for all three superficial knee extensors. Mean time to exhaustion was 5.96 ± 1.40 min, coefficient of variation was 8.42 ± 6.24%, typical error of measurement was 0.30 min and intraclass correlation was 0.795. MVC torque decreased shortly after exhaustion for all angular velocities (all P < 0.001. MVC60 and MVC100 recovered between P20 (P < 0.05 and exhaustion and then plateaued. MVC140 recovered only at P40 (P < 0.05. High intensity OLDE did not alter maximal EMG RMS of the three superficial knee extensors during MVC. The results of this study demonstrate that this novel high intensity OLDE protocol could be reliably used to measure muscle endurance, and that muscle fatigue induced by high intensity OLDE should be examined within ~ 30 s following exhaustion.

  10. 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.

  11. 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.

  12. EFFECT OF EXERCISE INTENSITY ON DIFFERENTIATED AND UNDIFFERENTIATED RATINGS OF PERCEIVED EXERTION DURING CYCLE AND TREADMILL EXERCISE IN RECREATIONALLY ACTIVE AND TRAINED WOMEN

    Directory of Open Access Journals (Sweden)

    Melinda R. Bolgar

    2010-12-01

    Full Text Available The purpose of the study is to examine the effect of aerobic exercise intensity on components of the differentiated perceived exertion model in young women performing weight bearing and non-weight bearing aerobic exercise. Subjects were 18-25 yr old women who were recreationally active (n = 19; VO2max = 33.40 ml·kg-1·min-1 and trained (N = 22; VO2max = 43.3 ml·kg-1·min-1. Subjects underwent two graded exercise tests (GXT on a treadmill and bike which were separated by 48 hours. RPE-Overall, -Legs, and -Chest, as well as oxygen uptake (VO2 and heart rate were recorded each minute. Individual regression analyses were used to identify RPE-Overall,-Legs, and -Chest at 40, 60, 80% VO2max/peak. Separate two factor (site (3 x intensity (3 ANOVAs with repeated measures on site and intensity were computed for each training status. Furthermore, RPE responses were also examined with a one factor (site (3 within subject ANOVA with repeated measure on site at the ventilatory breakpoint. For both the recreationally active and trained groups no significant differences were observed for RPE-Overall, -Legs, and -Chest during treadmill exercise. However, for cycling exercise results indicated that RPE-Legs was significantly greater at all exercise intensities than RPE-Overall and RPE-Chest for trained subjects while for recreationally active subjects RPE-Legs was only significantly higher at the highest exercise intensity. Responses at the ventilatory breakpoint during cycle exercise indicated that RPE-Legs was significantly greater than RPE-Chest and RPE-Overall for trained subjects but not for recreationally active subjects. Signal dominance was not observed at an intensity equivalent to the ventilatory breakpoint during treadmill exercise in either of the groups. In recreationally active and trained females signal dominance was demonstrated only during cycling exercise, but not during treadmill exercise. Signal integration could not be demonstrated during

  13. Effect of motivational music on lactate levels during recovery from intense exercise.

    Science.gov (United States)

    Eliakim, Michal; Bodner, Ehud; Eliakim, Alon; Nemet, Dan; Meckel, Yoav

    2012-01-01

    The effects of music played during an exercise task on athletic performance have been previously studied. Yet, these results are not applicable for competitive athletes, who can use music only during warm-up or recovery from exercise. Therefore, the aim of this study was to determine the effect of motivational music (music that stimulates or inspires physical activity) during recovery from intense exercise, on activity pattern, rate of perceived exertion (RPE), and blood lactate concentration. Twenty young, active men (mean age 26.2 ± 2.1 years) performed a 6-minute run at peak oxygen consumption speed (predetermined from the VO(2) max test). The mean heart rate (HR), RPE, number of steps (determined by step counter), and blood lactate concentrations were determined at 3, 6, 9, 12, and 15 minutes during the recovery from the exercise, with and without motivational music (2 separate sessions, at random order). There was no difference in the mean HR during the recovery with and without music. Listening to motivational music during the recovery was associated with increased voluntary activity of the participants, determined by increased number of steps (499.4 ± 220.1 vs. 413.2 ± 150.6 steps, with and without music, respectively; p ≤ 0.05). The increased number of steps during the recovery was accompanied by a significantly greater decrease in blood lactate concentration percentage (28.1 ± 12.2 vs. 22.8 ± 10.9%, with and without music, respectively, p ≤ 0.05). This was associated with a greater decrease in RPE (77.7 ± 14.4 vs. 73.1 ± 14.7% with and without music, respectively; p ≤ 0.05). Our results suggest that listening to motivational music during nonstructured recovery from intense exercise leads to increased activity, faster lactate clearance, and reduced RPE and therefore may be used by athletes in their effort to enhance recovery.

  14. Fat metabolism during low-intensity exercise in endurance-trained and untrained men.

    Science.gov (United States)

    Klein, S; Coyle, E F; Wolfe, R R

    1994-12-01

    Whole body lipid kinetics were evaluated during basal resting conditions, 4 h of treadmill exercise eliciting an oxygen uptake of 20 ml.kg-1.min-1, and 1 h of recovery in five untrained and five endurance-trained men. Glycerol and free fatty acid (FFA) rate of appearance (Ra) values in plasma were determined by infusing [2H5]glycerol and [1-13C]palmitate, respectively, and lipid oxidation was determined by indirect calorimetry. The lipolytic response to 4 h of exercise, expressed as the average glycerol and FFA Ra values, was similar in both trained (9.85 +/- 1.02 and 24.64 +/- 3.76 mumol.kg-1.min-1, respectively) and untrained subjects (11.29 +/- 0.99 and 24.13 +/- 0.39 mumol.kg-1.min-1, respectively). However, mean triglyceride oxidation was greater during exercise in the trained than in the untrained group (7.51 +/- 0.26 and 5.67 +/- 0.51 mumol.kg-1.min-1, respectively; P untrained subjects. We conclude that highly trained male endurance runners use more fat as a fuel during low-intensity exercise than do untrained healthy men despite similar rates of lipolysis and FFA uptake from plasma. Therefore, the increase in fat oxidation must be related to an increased percentage of FFA uptake oxidized, a greater contribution from intramuscular triglyceride stores, or both. Additionally, lipid kinetics return to baseline more rapidly in trained than in untrained subjects after completing an exercise bout of the same absolute intensity.

  15. The Relationship Between Exercise Intensity and Sleep Quality in People Hospitalised Due to Affective Disorders: A Pilot Study.

    Science.gov (United States)

    Stanton, Robert; Donohue, Trish; Garnon, Michelle; Happell, Brenda

    2016-01-01

    Individuals with mental illness experience poorer sleep quality compared to the general population. Exercise may improve sleep quality through a reduction in arousal, however the association between perceived exercise intensity and sleep quality for this population is largely unknown. Forty inpatient mental health consumers reported perceived exertion prior to, and immediately following, a morning session of combined aerobic and strengthening exercise. Self-reported sleep quality was reported immediately upon waking the day following the acute exercise session. Pearson's correlations examined the relationship between exercise intensity and sleep quality. A significant negative correlation was observed between post-exercise exertion and sleep quality (r = -0.32, p = 0.045). A reduction in arousal may explain the observed effects for people with anxiety disorders.

  16. Beetroot Juice Supplementation Improves High-Intensity Intermittent Type Exercise Performance in Trained Soccer Players

    Directory of Open Access Journals (Sweden)

    Jean Nyakayiru

    2017-03-01

    Full Text Available It has been shown that nitrate supplementation can enhance endurance exercise performance. Recent work suggests that nitrate ingestion can also increase intermittent type exercise performance in recreational athletes. We hypothesized that six days of nitrate supplementation can improve high-intensity intermittent type exercise performance in trained soccer players. Thirty-two male soccer players (age: 23 ± 1 years, height: 181 ± 1 m, weight: 77 ± 1 kg, playing experience: 15.2 ± 0.5 years, playing in the first team of a 2nd or 3rd Dutch amateur league club participated in this randomized, double-blind cross-over study. All subjects participated in two test days in which high-intensity intermittent running performance was assessed using the Yo-Yo IR1 test. Subjects ingested nitrate-rich (140 mL; ~800 mg nitrate/day; BR or a nitrate-depleted beetroot juice (PLA for six subsequent days, with at least eight days of wash-out between trials. The distance covered during the Yo-Yo IR1 was the primary outcome measure, while heart rate (HR was measured continuously throughout the test, and a single blood and saliva sample were collected just prior to the test. Six days of BR ingestion increased plasma and salivary nitrate and nitrite concentrations in comparison to PLA (p < 0.001, and enhanced Yo-Yo IR1 test performance by 3.4 ± 1.3% (from 1574 ± 47 to 1623 ± 48 m; p = 0.027. Mean HR was lower in the BR (172 ± 2 vs. PLA trial (175 ± 2; p = 0.014. Six days of BR ingestion effectively improves high-intensity intermittent type exercise performance in trained soccer players.

  17. The Intensive Diet and Exercise for Arthritis (IDEA) trial: design and rationale.

    Science.gov (United States)

    Messier, Stephen P; Legault, Claudine; Mihalko, Shannon; Miller, Gary D; Loeser, Richard F; DeVita, Paul; Lyles, Mary; Eckstein, Felix; Hunter, David J; Williamson, Jeff D; Nicklas, Barbara J

    2009-07-28

    Obesity is the most modifiable risk factor, and dietary induced weight loss potentially the best nonpharmacologic intervention to prevent or to slow osteoarthritis (OA) disease progression. We are currently conducting a study to test the hypothesis that intensive weight loss will reduce inflammation and joint loads sufficiently to alter disease progression, either with or without exercise. This article describes the intervention, the empirical evidence to support it, and test-retest reliability data. This is a prospective, single-blind, randomized controlled trial. The study population consists of 450 overweight and obese (BMI = 27-40.5 kg/m2) older (age > or = 55 yrs) adults with tibiofemoral osteoarthritis. Participants are randomized to one of three 18-month interventions: intensive dietary restriction-plus-exercise; exercise-only; or intensive dietary restriction-only. The primary aims are to compare the effects of these interventions on inflammatory biomarkers and knee joint loads. Secondary aims will examine the effects of these interventions on function, pain, and mobility; the dose response to weight loss on disease progression; if inflammatory biomarkers and knee joint loads are mediators of the interventions; and the association between quadriceps strength and disease progression. Test-retest reliability results indicated that the ICCs for knee joint load variables were excellent, ranging from 0.86 - 0.98. Knee flexion/extension moments were most affected by BMI, with lower reliability with the highest tertile of BMI. The reliability of the semi-quantitative scoring of the knee joint using MRI exceeded previously reported results, ranging from a low of 0.66 for synovitis to a high of 0.99 for bone marrow lesion size. The IDEA trial has the potential to enhance our understanding of the OA disease process, refine weight loss and exercise recommendations in this prevalent disease, and reduce the burden of disability. NCT00381290.

  18. Effects of exercise intensity on postexercise hypotension after resistance training session in overweight hypertensive patients.

    Science.gov (United States)

    Cavalcante, Paula Andréa M; Rica, Roberta L; Evangelista, Alexandre L; Serra, Andrey J; Figueira, Aylton; Pontes, Francisco Luciano; Kilgore, Lon; Baker, Julien S; Bocalini, Danilo S

    2015-01-01

    Among all nonpharmacological treatments, aerobic or resistance training (RT) has been indicated as a significantly important strategy to control hypertension. However, postexercise hypotension responses after intensity alterations in RT are not yet fully understood. The purpose of this study was to compare the outcomes of differing intensities of RT on hypertensive older women. Twenty hypertensive older women participated voluntarily in this study. After a maximum voluntary contraction test (one repetition maximum) and determination of 40% and 80% experimental loads, the protocol (3 sets/90″ interset rest) was performed in a single session with the following exercises: leg press, leg extension, leg curl, chest press, elbow flexion, elbow extension, upper back row, and abdominal flexion. Systolic and diastolic blood pressures were evaluated at rest, during exercise peak, and after 5, 10, 15, 30, 45, and 60 minutes of exercise and compared to the control. Both experimental loads were effective (Pcontrols, after 30, 45, and 60 minutes, respectively, at 40% (113±2, 112±4, and 110±3 mmHg) and 80% (111±3, 111±4, and 110±4 mmHg). Both procedures promoted hypotension with similar systolic blood pressures (40%: -11%±1.0% and 80%: -13%±0.5%), mean arterial blood pressures (40%: -12%±5.5% and 80%: -12%±3.4%), and rate-pressure products (40%: -15%±2.1% and 80%: -17%±2.4%) compared to control measures (systolic blood pressure: 1%±1%, mean arterial blood pressure:\\ 0.6%±1.5%, rate-pressure product: 0.33%±1.1%). No differences were found in diastolic blood pressure and heart rate measures. In conclusion, hypertensive older women exhibit postexercise hypotension independently of exercise intensity without expressed cardiovascular overload during the session.

  19. The Intensive Diet and Exercise for Arthritis (IDEA trial: design and rationale

    Directory of Open Access Journals (Sweden)

    Eckstein Felix

    2009-07-01

    Full Text Available Abstract Background Obesity is the most modifiable risk factor, and dietary induced weight loss potentially the best nonpharmacologic intervention to prevent or to slow osteoarthritis (OA disease progression. We are currently conducting a study to test the hypothesis that intensive weight loss will reduce inflammation and joint loads sufficiently to alter disease progression, either with or without exercise. This article describes the intervention, the empirical evidence to support it, and test-retest reliability data. Methods/Design This is a prospective, single-blind, randomized controlled trial. The study population consists of 450 overweight and obese (BMI = 27–40.5 kg/m2 older (age ≥ 55 yrs adults with tibiofemoral osteoarthritis. Participants are randomized to one of three 18-month interventions: intensive dietary restriction-plus-exercise; exercise-only; or intensive dietary restriction-only. The primary aims are to compare the effects of these interventions on inflammatory biomarkers and knee joint loads. Secondary aims will examine the effects of these interventions on function, pain, and mobility; the dose response to weight loss on disease progression; if inflammatory biomarkers and knee joint loads are mediators of the interventions; and the association between quadriceps strength and disease progression. Results Test-retest reliability results indicated that the ICCs for knee joint load variables were excellent, ranging from 0.86 – 0.98. Knee flexion/extension moments were most affected by BMI, with lower reliability with the highest tertile of BMI. The reliability of the semi-quantitative scoring of the knee joint using MRI exceeded previously reported results, ranging from a low of 0.66 for synovitis to a high of 0.99 for bone marrow lesion size. Discussion The IDEA trial has the potential to enhance our understanding of the OA disease process, refine weight loss and exercise recommendations in this prevalent disease, and

  20. Long-Term Low Intensity Physical Exercise Attenuates Heart Failure Development in Aging Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Luana U. Pagan

    2015-04-01

    Full Text Available Background: Physical exercise is a strategy to control hypertension and attenuate pressure overload-induced cardiac remodeling. The influence of exercise on cardiac remodeling during uncontrolled hypertension is not established. We evaluated the effects of a long-term low intensity aerobic exercise protocol on heart failure (HF development and cardiac remodeling in aging spontaneously hypertensive rats (SHR. Methods: Sixteen month old SHR (n=50 and normotensive Wistar-Kyoto (WKY, n=35 rats were divided into sedentary (SED and exercised (EX groups. Rats exercised in treadmill at 12 m/min, 30 min/day, 5 days/week, for four months. The frequency of HF features was evaluated at euthanasia. Statistical analyses: ANOVA and Tukey or Mann-Whitney, and Goodman test. Results: Despite slightly higher systolic blood pressure, SHR-EX had better functional capacity and lower HF frequency than SHR-SED. Echocardiography and tissue Doppler imaging showed no differences between SHR groups. In SHR-EX, however, left ventricular (LV systolic diameter, larger in SHR-SED than WKY-SED, and endocardial fractional shortening, lower in SHR-SED than WKY-SED, had values between those in WKY-EX and SHR-SED not differing from either group. Myocardial function, assessed in LV papillary muscles, showed improvement in SHR-EX over SHR-SED and WKY-EX. LV myocardial collagen fraction and type I and III collagen gene expression were increased in SHR groups. Myocardial hydroxyproline concentration was lower in SHR-EX than SHR-SED. Lysyl oxidase gene expression was higher in SHR-SED than WKY-SED. Conclusion: Exercise improves functional capacity and reduces decompensated HF in aging SHR independent of elevated arterial pressure. Improvement in functional status is combined with attenuation of LV and myocardial dysfunction and fibrosis.

  1. Hypotensive effects of resistance exercises performed at different intensities and same work volumes

    Directory of Open Access Journals (Sweden)

    Polito Marcos Doederlein

    2003-01-01

    Full Text Available The aim of this paper was to compare the effects of two sequences of resistance exercises (RE, with different intensities but same training volume, on post-exercise blood pressure responses. Sixteen young subjects with previous experience in RE were evaluated during three non-following days in chest press, legpress, pulley pull down, leg curl, shoulder press, and biceps curl. On the first day, the load associated with six maximal repetitions (6RM were determined for each exercise. On the second day, three sets of 6RM were performed (SEQ6, with a two minute interval between the sets. On the last day, the same procedure was repeated, but using 12 repetitions with 50% of 6RM load (SEQ12. Rest BP was measured before the sequences by auscultatory method. Post-exercise resting BP was measured each 10 minutes by ambulatory BP monitoring during 60 minutes. The magnitude and duration of BP variability were compared by repeated ANOVA measures followed by Tuckey post-hoc test (p < 0.05. A significant reduction in diastolic blood pressure (DBP was observed in the first 20 minutes after SEQ12, but not after SEQ6. SEQ12 elicited significant decline in systolic blood pressure (SBP, at least during the first 50 minutes after the exercise, while significant reductions were observed in all measures after SEQ6. There were no significant differences between the absolute values of DBP and SBP after both sequences. In conclusion: a RE had hypotensive effects on blood pressure, mainly SBP; b the absolute decline of SBP seem not to be influenced by different interactions between workload and number of repetitions; c higher workloads seem to extend the total time of SBP post-exercise reduction; d the number of repetitions seems to have more influence on DBP than SBP, but for a short period of time.

  2. Low Intensity Resistance Exercise Training with Blood Flow Restriction: Insight into Cardiovascular Function, and Skeletal Muscle Hypertrophy in Humans

    OpenAIRE

    Park, Song-Young; Kwak, Yi Sub; Harveson, Andrew; Weavil, Joshua C.; Seo, Kook E.

    2015-01-01

    Attenuated functional exercise capacity in elderly and diseased populations is a common problem, and stems primarily from physical inactivity. Decreased function and exercise capacity can be restored by maintaining muscular strength and mass, which are key factors in an independent and healthy life. Resistance exercise has been used to prevent muscle loss and improve muscular strength and mass. However, the intensities necessary for traditional resistance training to increase muscular strengt...

  3. Effect of pre-exercise carbohydrate ingestion on plasma cytokine, stress hormone, and neutrophil degranulation responses to continuous, high-intensity exercise.

    Science.gov (United States)

    Lancaster, Graeme I; Jentjens, Roy L P G; Moseley, Luke; Jeukendrup, Asker E; Gleeson, Michael

    2003-12-01

    The purpose of the present study was to examine the effect of pre-exercise carbohydrate (CHO) ingestion on circulating leukocyte numbers, plasma interleukin (IL)-6, plasma cortisol, and lipopolysaccharide (LPS)-stimulated neutrophil degranulation responses in moderately trained male cyclists who completed approximately 1-h of high-intensity cycling. The influence of the timing of pre-exercise CHO ingestion was investigated in 8 subjects who consumed 75 g CHO as a glucose solution at either 15 (-15 trial), or 75 (-75 trial) min before the onset of exercise. The influence of the amount of pre-exercise CHO ingestion was investigated in a further 10 subjects who consumed either 25 g or 200 g CHO as a glucose solution or a placebo 45 min before the onset of exercise. At the onset of exercise in the timing experiment, the plasma glucose concentration was significantly (p exercise period. In the -15 trial, plasma glucose level was well maintained, and the plasma cortisol concentration and N/L ratio were not significantly elevated above resting levels. However, LPS-stimulated neutrophil degranulation was similar in the -15 and -75 trials. The amount of CHO ingested had no effect on the magnitude of the rise in the N/L ratio compared with placebo when consumed 45 min pre-exercise. Finally, although an exercise-induced increase in the plasma IL-6 concentration was observed, this effect was independent of pre-exercise CHO ingestion.

  4. In vivo ATP synthesis rates in single human muscles during high intensity exercise

    Science.gov (United States)

    Walter, Glenn; Vandenborne, Krista; Elliott, Mark; Leigh, John S

    1999-01-01

    In vivo ATP synthesis rates were measured in the human medial gastrocnemius muscle during high intensity exercise using localized 31P-magnetic resonance spectroscopy (31P-MRS). Six-second localized spectra were acquired during and following a 30 s maximal voluntary rate exercise using a magnetic resonance image-guided spectral localization technique. During 30 s maximal voluntary rate exercise, ATPase fluxes were predominantly met by anaerobic ATP sources. Maximal in vivo glycogenolytic rates of 207 ± 48 mM ATP min−1 were obtained within 15 s, decreasing to 72 ± 34 mM ATP min−1 by the end of 30 s. In contrast, aerobic ATP synthesis rates achieved 85 ± 2 % of their maximal capacity within 9 s and did not change throughout the exercise. The ratio of peak glycolytic ATP synthesis rate to maximal oxidative ATP synthesis was 2.9 ± 0.9. The non-Pi, non-CO2 buffer capacity was calculated to be 27.0 ± 6.2 slykes (millimoles acid added per unit change in pH). At the cessation of exercise, Pi, phosphomonoesters and CO2 were predicted to account for 17.2 ± 1.5, 5.57 ± 0.97 and 2.24 ± 0.34 slykes of the total buffer capacity. Over the approximately linear range of intracellular pH recovery following the post-exercise acidification, pHi recovered at a rate of 0.19 ± 0.03 pH units min−1. Proton transport capacity was determined to be 16.4 ± 4.1 mM (pH unit)−1 min−1 and corresponded to a maximal proton efflux rate of 15.3 ± 2.7 mM min−1. These data support the observation that glycogenolytic and glycolytic rates are elevated in vivo in the presence of elevated Pi levels. The data do not support the hypothesis that glycogenolysis follows Michealis-Menten kinetics with an apparent Km for [Pi]in vivo. In vivo -measured ATP utilization rates and the initial dependence on PCr and glycolysis were similar to those previously reported in in situ studies involving short duration, high intensity exercise. This experimental approach presents a non

  5. Influence of exercise intensity on skeletal muscle blood flow, O2 extraction and O2 uptake on‐kinetics

    National Research Council Canada - National Science Library

    Jones, Andrew M; Krustrup, Peter; Wilkerson, Daryl P; Berger, Nicolas J; Calbet, José A; Bangsbo, Jens

    2012-01-01

    •  Following the start of low‐intensity exercise in healthy humans, it has been established that the kinetics of muscle O 2 delivery is faster than, and does not limit, the kinetics of muscle O 2 uptake...

  6. High-intensity interval exercise training for public health: a big HIT or shall we HIT it on the head?

    National Research Council Canada - National Science Library

    Biddle, Stuart J H; Batterham, Alan M

    2015-01-01

    ... question. Rather, the effectiveness of this form of exercise is at stake. In this paper we debate the issues concerning the likely success or failure of high-intensity interval training interventions for population-level health promotion...

  7. Impact of an intensive dynamic exercise program on oxidative stress and on the outcome in patients with fibromyalgia

    Directory of Open Access Journals (Sweden)

    Amal F Soliman

    2016-01-01

    Conclusion Twelve weeks of intensive dynamic exercise program should be recommended to patients with FM as it was effective in decreasing the oxidative stress parameters, increasing the antioxidant parameters, and improving the clinical outcome of this disease.