Pedaling rate is an important determinant of human oxygen uptake during exercise on the cycle ergometer

This study examined the influence of maturation on the oxygen uptake efficiency slope (OUES) in healthy male subjects. Seventy-six healthy male subjects (8–27 yr) were divided into groups based on maturation status: prepubertal (PP), midpubertal (MP), late-pubertal (LP), and young-adult (YA) males. Puberty status was determined by physical examination. Subjects performed a graded exercise test on a cycle ergometer to determine OUES. Group differences were assessed using a one-way ANOVA. OUES values (VO2L·min1/log10VEL·min−1) were lower in PP and MP compared with LP and YA (p < .05). When OUES was expressed relative to body mass (VO2mL·kg−1·min−1/log10VEmL·kg−1·min−1) differences between groups reversed whereby PP and MP had higher mass relative OUES values compared with LP and YA (p < .05). Adjusting OUES by measures of body mass failed to eliminate differences across maturational groups. This suggests that qualitative factors, perhaps related to oxidative metabolism, account for the responses observed in this study.

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Central and peripheral adaptations of the gas transport system to one-leg training

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y81-177 ◽

1981 ◽

Vol 59 (11) ◽

pp. 1146-1154 ◽

Cited By ~ 5

Author(s):

S. G. Thomas ◽

D. A. Cunningham ◽

M. J. Plyley ◽

D. R. Boughner ◽

R. A. Cook

Keyword(s):

Cardiac Output ◽

Oxygen Uptake ◽

Endurance Training ◽

Maximal Oxygen Uptake ◽

Enzyme Activities ◽

Cardiovascular Responses ◽

Cycle Ergometer ◽

Left Ventricular ◽

Enzyme Analysis ◽

Ergometer Exercise

The role of central and peripheral adaptations in the response to endurance training was examined. Changes in cardiac structure and function, oxygen extraction, and muscle enzyme activities following one-leg training were studied.Eleven subjects (eight females, three males) trained on a cycle ergometer 4 weeks with one leg (leg 1), then 4 weeks with the second leg (leg 2). Cardiovascular responses to exercise with both legs and each leg separately were evaluated at entry (T1), after 4 weeks of training (T2), and after a second 4 weeks of training (T3). Peak oxygen uptake ([Formula: see text] peak) during exercise with leg 1 (T1 to T2 increased 19.8% (P < 0.05) and during exercise with leg 2 (T2 to T3 increased 16.9% (P < 0.05). Maximal oxygen uptake with both legs increased 7.9% from T1 to T2 and 9.4% from T2 to T3 (P < 0.05). During exercise at 60% of [Formula: see text] peak, cardiac output [Formula: see text] was increased significantly only when the trained leg was exercised. [Formula: see text] increased 12.2% for leg 1 between T1 and T2 and 13.0% for leg 2 between T2 and T3 (P < 0.05). M-mode echocardiographic assessment of left ventricular internal diameter at diastole and peak velocity of circumferential fibre shortening at rest or during supine cycle ergometer exercise at T1 and T3 revealed no training induced changes in cardiac dimensions or function. Enzyme analysis of muscle biopsy samples from the vastus lateralis (At T1, T2, T3) revealed no consistent pattern of change in aerobic (malate dehydrogenase and 3-hydroxyacyl-CoA dehydrogenase) or anaerobic (phosphofructokinase, lactate dehydroginase, and creatine kinase) enzyme activities. Increases in cardiac output and maximal oxygen uptake which result from short duration endurance training can be achieved, therefore, without measurable central cardiac adaptation. The absence of echocardio-graphically determined changes in cardiac dimensions and contractility and the absence of an increase in cardiac output during exercise with the nontrained leg following training of the contralateral limb support this conclusion.

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Plasma glucose kinetics during exercise in subjects with high and low lactate thresholds

Journal of Applied Physiology ◽

10.1152/jappl.1992.73.5.1873 ◽

1992 ◽

Vol 73 (5) ◽

pp. 1873-1880 ◽

Cited By ~ 37

Author(s):

A. R. Coggan ◽

W. M. Kohrt ◽

R. J. Spina ◽

J. P. Kirwan ◽

D. M. Bier ◽

...

Keyword(s):

Oxygen Uptake ◽

Plasma Glucose ◽

Glucose Oxidation ◽

Citrate Synthase ◽

Metabolic Response ◽

Vastus Lateralis ◽

Cycle Ergometer ◽

Vastus Lateralis Muscle ◽

Respiratory Capacity ◽

Group A

The purpose of this study was to test the hypothesis that the rate of plasma glucose oxidation during exercise is inversely related to muscle respiratory capacity. To this end, 14 subjects were studied: in 7 of these subjects, the blood lactate threshold (LT) occurred at a relatively high intensity [i.e., at 65 +/- 2% of peak cycle ergometer oxygen uptake (VO2 peak)], whereas in the other 7 subjects, LT occurred at a relatively low intensity (i.e., at 45 +/- 2% of VO2 peak). VO2peak did not differ between the two groups, but citrate synthase activity in the vastus lateralis muscle was 53% higher (P < 0.05) in the high LT group. A primed continuous infusion of [U-13C]glucose was used to quantify rates of glucose appearance (Ra), disappearance (Rd), and oxidation (R(ox)) during 90 min of exercise at 55% VO2peak. Although both absolute and relative rates of oxygen uptake during exercise were similar in the two groups, mean Ra and Rd were 17% lower (P < 0.001) in the high LT group, and mean R(ox) was 25% lower (21.0 +/- 2.6 vs. 27.9 +/- 2.6 mumol.min-1.kg-1; P < 0.001). The percentage of total energy derived from glucose oxidation was inversely related to muscle citrate synthase activity (r = -0.85; P < 0.01). These data support the concept that skeletal muscle respiratory capacity has a major role in determining the metabolic response to submaximal exercise.

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Oxygen uptake in water polo, comparison and agreement in cycle ergometer and eggbeater kick: A pilot study

Motriz Revista de Educação Física ◽

10.1590/s1980-6574201600030013 ◽

2016 ◽

Vol 22 (3) ◽

pp. 211-216

Author(s):

Ligia Ignêz Engelmann ◽

Giane Veiga Liedtke ◽

Flávio de Souza Castro

Keyword(s):

Pilot Study ◽

Oxygen Uptake ◽

Cycle Ergometer ◽

Water Polo

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Metabolic, Cardiac, and Hemorheological Responses to Submaximal Exercise under Light and Moderate Hypobaric Hypoxia in Healthy Men

Biology ◽

10.3390/biology11010144 ◽

2022 ◽

Vol 11 (1) ◽

pp. 144

Author(s):

Hun-Young Park ◽

Jeong-Weon Kim ◽

Sang-Seok Nam

Keyword(s):

Oxygen Uptake ◽

Blood Lactate ◽

Minute Ventilation ◽

Random Order ◽

Cycle Ergometer ◽

Submaximal Exercise ◽

Erythrocyte Deformability ◽

Moderate Hypoxia ◽

Healthy Men ◽

Significant Difference

We compared the effects of metabolic, cardiac, and hemorheological responses to submaximal exercise under light hypoxia (LH) and moderate hypoxia (MH) versus normoxia (N). Ten healthy men (aged 21.3 ± 1.0 years) completed 30 min submaximal exercise corresponding to 60% maximal oxygen uptake at normoxia on a cycle ergometer under normoxia (760 mmHg), light hypoxia (596 mmHg, simulated 2000 m altitude), and moderate hypoxia (526 mmHg, simulated 3000 m altitude) after a 30 min exposure in the respective environments on different days, in a random order. Metabolic parameters (oxygen saturation (SPO2), minute ventilation, oxygen uptake, carbon dioxide excretion, respiratory exchange ratio, and blood lactate), cardiac function (heart rate (HR), stroke volume, cardiac output, and ejection fraction), and hemorheological properties (erythrocyte deformability and aggregation) were measured at rest and 5, 10, 15, and 30 min after exercise. SPO2 significantly reduced as hypoxia became more severe (MH > LH > N), and blood lactate was significantly higher in the MH than in the LH and N groups. HR significantly increased in the MH and LH groups compared to the N group. There was no significant difference in hemorheological properties, including erythrocyte deformability and aggregation. Thus, submaximal exercise under light/moderate hypoxia induced greater metabolic and cardiac responses but did not affect hemorheological properties.

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Effect of Posture on Muscle Activity and Oxygen Uptake in Cycle Ergometer

The Korean Journal of Sports Medicine ◽

10.5763/kjsm.2011.29.1.37 ◽

2011 ◽

Vol 29 (1) ◽

pp. 37 ◽

Cited By ~ 2

Author(s):

Yoon-Kyung Park ◽

In-Keol Bang ◽

Young-Joo Kim ◽

Chul Kim ◽

Jeong-Beom Lee ◽

...

Keyword(s):

Oxygen Uptake ◽

Muscle Activity ◽

Cycle Ergometer

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Perceived Exertion during Physical Exercise among Individuals High and Low in Fitness

Perceptual and Motor Skills ◽

10.2466/pms.1996.82.2.419 ◽

1996 ◽

Vol 82 (2) ◽

pp. 419-424 ◽

Cited By ~ 24

Author(s):

Antonios K. Travlos ◽

Daniel Q. Marisi

Keyword(s):

Heart Rate ◽

Physical Exercise ◽

Oxygen Uptake ◽

Core Temperature ◽

Maximal Oxygen Uptake ◽

Perceived Exertion ◽

Cycle Ergometer ◽

Ratings Of Perceived Exertion ◽

Workload Analysis ◽

Fitness Level

This study was conducted to investigate the influence of fitness level and gradually increased amounts of exercise on individuals' ratings of perceived exertion (RPE). 20 men served as paid subjects. They were divided into groups of high (>56 ml/kg/min.) and low fitness (<46 ml/kg/min.) according to their maximal oxygen uptake (VO2 max). Participants were required to pedal on a cycle ergometer at a progressively increased workload (every 10 min.) corresponding to 40, 50, 60, 70, and 80% of individual VO2 max values. Heart rates, RPE, and core temperatures were recorded every 5th minute after the initiation of exercising at a specific workload. Analysis indicated that, when controlling for VO2 max values, elevations of heart rate and core temperature were not affected by fitness. However, highly fit individuals perceived themselves under less exertion than did the group low in fitness. Correlations showed that, taking into consideration fitness, there is a stronger relationship between RPE and heart rate and RPE and core temperature for the highly fit individuals than for the less fit.

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Do we underestimate maximal oxygen uptake in cancer survivors? Findings from a supramaximal verification test

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2019-0560 ◽

2020 ◽

Vol 45 (5) ◽

pp. 486-492 ◽

Cited By ~ 2

Author(s):

Justine Schneider ◽

Kathrin Schlüter ◽

Joachim Wiskemann ◽

Friederike Rosenberger

Keyword(s):

Oxygen Uptake ◽

Cancer Survivors ◽

Maximal Oxygen Uptake ◽

Cardiopulmonary Exercise Test ◽

Cycle Ergometer ◽

Peak Power Output ◽

Primary Therapy ◽

Individual Level ◽

The Individual

Cancer survivors demonstrate a reduced maximal oxygen uptake, which is clinically relevant in terms of overall survival. However, it remains uncertain whether they attain their “true maximal oxygen uptake” in a cardiopulmonary exercise test (CPET). In the present study, a supramaximal verification bout (Verif) was applied in cancer survivors to confirm attainment of maximal oxygen uptake. Seventy-five participants (age, 61 ± 12 years; n = 43 females with breast cancer and n = 32 males with prostate cancer, 6–52 weeks after primary therapy) performed a CPET on a cycle ergometer and a Verif at 110% peak power output. As verification criterion, maximal oxygen uptake in Verif should not exceed maximal oxygen uptake in CPET by >3%. On average, maximal oxygen uptake was significantly lower in Verif compared with CPET (1.60 ± 0.38 L·min–1 vs. 1.65 ± 0.36 L·min–1, p = .023). On the individual level, n = 51 (68%) satisfied the verification criterion, whereas n = 24 (32%) demonstrated a higher maximal oxygen uptake in Verif. n = 69 (92%) fulfilled ≥2 secondary criteria for maximal exhaustion in the CPET. While maximal oxygen uptake was not underestimated in the CPET on average, one-third of cancer survivors did not attain their true maximal oxygen uptake. Verif appears feasible and beneficial to confirm true maximal oxygen uptake in this population. Furthermore, it might be more reliable than secondary criteria for maximal exhaustion. Novelty In about one-third of cancer survivors, maximal oxygen uptake is underestimated by a CPET. This underestimation of maximal oxygen uptake is not necessarily indicated by secondary criteria for maximal exhaustion. A supramaximal verification bout appears feasible and helpful for the determination of maximal oxygen uptake in cancer survivors.

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Effect of Sprint Interval Exercise on Postexercise Metabolism and Blood Pressure in Adolescents

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.22.1.47 ◽

2012 ◽

Vol 22 (1) ◽

pp. 47-54 ◽

Cited By ~ 17

Author(s):

Stephen F. Burns ◽

Hnin Hnin Oo ◽

Anh Thanh Thuy Tran

Keyword(s):

Blood Pressure ◽

Oxygen Consumption ◽

Oxygen Uptake ◽

Interval Training ◽

Fat Oxidation ◽

Substrate Oxidation ◽

Cycle Ergometer ◽

Normal Weight ◽

Interval Exercise ◽

Total Fat

The current study examined the effect of sprint interval exercise on postexercise oxygen consumption, respiratory-exchange ratio (RER), substrate oxidation, and blood pressure in adolescents. Participants were 10 normal-weight healthy youth (7 female), age 15–18 years. After overnight fasts, each participant undertook 2 trials in a random balanced order: (a) two 30-s bouts of sprint interval exercise on a cycle ergometer and (b) rested in the laboratory for an equivalent period. Timematched measurements of oxygen consumption, RER, and blood pressure were made 90 min into recovery, and substrate oxidation were calculated over the time period. Total postexercise oxygen uptake was significantly higher in the exercise than control trial over the 90 min (mean [SD]: control 20.0 [6.0] L, exercise 24.8 [9.8] L; p = .030). After exercise, RER was elevated above control but then fell rapidly and was lower than control 30–60 min postexercise, and fat oxidation was significantly higher in the exercise than control trial 45–60 min postexercise. However, total fat oxidation did not differ between trials (control 4.5 [2.5] g, exercise 5.4 [2.7] g; p = .247). Post hoc tests revealed that systolic blood pressure was significantly lower than in control at 90 min postexercise (control 104 [10] mm Hg, exercise 99 [10] mm Hg; p < .05). These data indicate that acute sprint interval exercise leads to short-term increases in oxygen uptake and reduced blood pressure in youth. The authors suggest that health outcomes in response to sprint interval training be examined in children.

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