Influence of acute passive stretching on the oxygen uptake vs work rate slope during an incremental cycle test

A two-test protocol (incremental/ramp (IWT) + supramaximal constant-load (CWR)) to affirm max and obviate reliance on secondary criteria has only been validated in highly fit children. In girls (n = 15) and boys (n = 12) with a wide range of VO2max (17–47 ml/kg/min), we hypothesized that this procedure would evince a VO2-WR plateau and unambiguous VO2max even in the presence of expiratory flow limitation (EFL). A plateau in the VO2-work rate relationship occurred in 75% of subjects irrespective of EFL There was a range in RER at max exercise for girls (0.97–1.14; mean 1.06 ± 0.04) and boys (0.98−1.09; mean 1.03 ± 0.03) such that 3/15 girls and 2/12 boys did not achieve the criterion RER. Moreover, in girls with RER > 1.0 it would have been possible to achieve this criterion at 78% VO2max. Boys achieved 92% VO2max at RER = 1.0. This was true also for HRmax where 8/15 girls’ and 6/12 boys’ VO2max would have been rejected based on HRmax being < 90% of age-predicted HRmax. In those who achieved the HRmax criterion, it represented a VO2 of 86% (girls) and 87% (boys) VO2max. We conclude that this two-test protocol confirms VO2max in children across a threefold range of VO2max irrespective of EFL and circumvents reliance on secondary criteria.

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The relationship between oxygen uptake reserve and heart rate reserve is affected by intensity and duration during aerobic exercise at constant work rate

Applied Physiology Nutrition and Metabolism ◽

10.1139/h11-100 ◽

2011 ◽

Vol 36 (6) ◽

pp. 839-847 ◽

Cited By ~ 8

Author(s):

Felipe A. Cunha ◽

Adrian W. Midgley ◽

Walace D. Monteiro ◽

Felipe K. Campos ◽

Paulo T.V. Farinatti

Keyword(s):

Heart Rate ◽

Oxygen Uptake ◽

Exercise Testing ◽

Exercise Intensity ◽

Maximal Exercise ◽

Work Rate ◽

Heart Rate Reserve ◽

Constant Work Rate ◽

The Stability ◽

The Relationship

The relationship between the percentage of heart rate reserve (%HRR) and percentage of oxygen uptake reserve (%VO2R) has been recommended for prescribing aerobic exercise intensity. However, this relationship was derived from progressive maximal exercise testing data, and the stability of the relationship during prolonged exercise at a constant work rate has not been established. The main aim of this study was to investigate the stability of the %VO2R–%HRR relationship during prolonged treadmill exercise bouts performed at 3 different constant work rates. Twenty-eight men performed 4 exercise tests: (i) a ramp-incremental maximal exercise test to determine maximal heart rate (HRmax) and maximal oxygen uptake (VO2max) and (ii) three 40-min exercise bouts at 60%, 70%, and 80% VO2R. HR and VO2 significantly increased over time and were influenced by exercise intensity (p < 0.001 and p = 0.004, respectively). A 1:1 relationship between %HRR and %VO2R, and between %HRR and %VO2max, was not observed, with mean differences of 8% (t = 5.2, p < 0.001) and 6% (t = 4.8, p < 0.001), respectively. The VO2 values predicted from the ACSM running equation were all significantly higher than the observed VO2 values (p < 0.001 for all comparisons), whereas a difference for HR was observed only for the tenth min of exercise at 80% VO2R (p = 0.041). In conclusion, the main finding of this study was that the %HRR–%VO2R relationship determined by linear regression, obtained from progressive maximal exercise testing, did not apply to prolonged treadmill running performed at 3 work rates.

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Effect of work rate increment on peak oxygen uptake during wheelchair ergometry in men with quadriplegia

Applied Ergonomics ◽

10.1016/0003-6870(93)90093-o ◽

1993 ◽

Vol 24 (2) ◽

pp. 131

Keyword(s):

Oxygen Uptake ◽

Peak Oxygen Uptake ◽

Work Rate ◽

Wheelchair Ergometry

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Increase in oxygen uptake to work rate increment (ΔVO2/ΔWR) during cardiopulmonary exercise testing: Correlation to COPD severity indicators, including BODE index

10.1183/13993003.congress-2015.pa2287 ◽

2015 ◽

Author(s):

Mahsa Mirdamadi ◽

Besharat Rahimi ◽

Enayat Safavi ◽

Hamidreza Abtahi ◽

Soheil Peiman

Keyword(s):

Oxygen Uptake ◽

Exercise Testing ◽

Cardiopulmonary Exercise Testing ◽

Work Rate ◽

Cardiopulmonary Exercise ◽

Bode Index

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Influence of exercise intensity on pulmonary oxygen uptake kinetics at the onset of exercise and recovery in male adolescents

Applied Physiology Nutrition and Metabolism ◽

10.1139/h07-154 ◽

2008 ◽

Vol 33 (1) ◽

pp. 107-117 ◽

Cited By ~ 18

Author(s):

Nicola Lai ◽

Melita M. Nasca ◽

Marco A. Silva ◽

Fatima T. Silva ◽

Brian J. Whipp ◽

...

Keyword(s):

Oxygen Uptake ◽

Slow Component ◽

Work Rate ◽

Moderate Intensity ◽

Heavy Exercise ◽

Pulmonary Oxygen Uptake ◽

Square Wave ◽

Male Adolescents ◽

Double Exponential ◽

Single Exponential

The dynamics of the pulmonary oxygen uptake (VO2) responses to square-wave changes in work rate can provide insight into bioenergetic processes sustaining and limiting exercise performance. The dynamic responses at the onset of exercise and during recovery have been investigated systematically and are well characterized at all intensities in adults; however, they have not been investigated completely in adolescents. We investigated whether adolescents display a slow component in their VO2 on- and off-kinetic responses to heavy- and very heavy-intensity exercise, as demonstrated in adults. Healthy African American male adolescents (n = 9, 14–17 years old) performed square-wave transitions on a cycle ergometer (from and to a baseline work rate of 20 W) to work rates of moderate (M), heavy (H), and very heavy (VH) intensity. In all subjects, the VO2 on-kinetics were best described with a single exponential at moderate intensity (τ1, on = 36 ± 11 s) and a double exponential at heavy (τ1, on = 29 ± 9 s; τ2, on = 197 ± 92 s) and very heavy (τ1, on = 36 ± 9 s; τ2, on = 302 ± 14 s) intensities. In contrast, the VO2 off-kinetics were best described with a single exponential at moderate (τ1, off = 48 ± 9 s) and heavy (τ1, off = 53 ± 7 s) intensities and a double exponential at very heavy (τ1, off = 51 ± 3 s; τ2, off = 471 ± 54 s) intensity. In summary, adolescents consistently displayed a slow component during heavy exercise (on- but not off- transition) and very heavy exercise (on- and off-transitions). Although the overall response dynamics in adolescents were similar to those previously observed in adults, their specific characterizations were different, particularly the lack of symmetry between the on- and off-responses.

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Psychological Affect at Different Ratings of Perceived Exertion in High-and Low-Active Women: A Study Using a Production Protocol

Perceptual and Motor Skills ◽

10.2466/pms.1996.82.3.1035 ◽

1996 ◽

Vol 82 (3) ◽

pp. 1035-1042 ◽

Cited By ~ 32

Author(s):

Gaynor Parfitt ◽

Roger Eston ◽

Declan Connolly

Keyword(s):

Steady State ◽

Oxygen Uptake ◽

Perceived Exertion ◽

Exercise Prescription ◽

Cycle Ergometer ◽

Work Rate ◽

Activity Levels ◽

Ratings Of Perceived Exertion ◽

Habitual Activity ◽

Positive Feelings

The purpose of this study was to examine psychological affect at different ratings of perceived exertion (RPE) in 15 high- and 15 low-active women. Both groups performed three steady-state exercise bouts on a cycle ergometer at RPEs 9, 13, and 17 and reported their affect in the last 20 sec. of and 5 min. after each work rate. There were no differences between groups in percentage of maximal oxygen uptake (% VO2max) at each RPE. Low-active women reported feeling significantly more negative at RPE 17 than RPE 9 and less positive than the high-active women at RPEs 9, 13, and 17. In addition, all subjects reported more positive feelings 5 min. postexercise than in the last 20 sec. of exercising, especially at RPE 17. These results have implications for exercise prescription in groups differing in habitual activity levels.

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Influence of crank rate on the slow component of pulmonary O2 uptake during heavy arm-crank exercise

Applied Physiology Nutrition and Metabolism ◽

10.1139/h05-039 ◽

2006 ◽

Vol 31 (3) ◽

pp. 292-301 ◽

Cited By ~ 6

Author(s):

Paul M Smith ◽

Eilidh McCrindle ◽

Mike Doherty ◽

Michael J Price ◽

Andrew M Jones

Keyword(s):

Oxygen Uptake ◽

Peak Power ◽

Slow Component ◽

Work Rate ◽

Rating Of Perceived Exertion ◽

Muscle Fibres ◽

External Work ◽

Tension Development ◽

Significant Difference ◽

The Mean

The principal aim of this study was to examine the influence of variations in crank rate on the slow component of the pulmonary oxygen uptake ([Formula: see text]O2) response to heavy-intensity arm-crank ergometry (ACE). We hypothesized that, for the same external work rate, a higher crank rate would elicit a greater amplitude of the [Formula: see text]O2 "slow component". Eleven healthy males (mean (± SD) age, 25 (±6) y; body mass, 89.1 (±10.7) kg; ACE [Formula: see text]O2 peak, 3.36 (±0.47) L·min-1) volunteered to participate. The subjects initially completed an incremental exercise test for the determination of [Formula: see text]O2 peak and peak power on an electrically braked arm ergometer. Subsequently, they completed "step" transitions from an unloaded baseline to a work rate requiring 70% of peak power: 2 at a crank rate of 50 r·min-1 (LO) and 2 at a crank rate of 90 r·min-1 (HI). Pulmonary gas exchange was measured on a breath-by-breath basis and [Formula: see text]O2 kinetics were evaluated from the mean response to each condition using non-linear regression techniques. In contradiction to our hypothesis, the [Formula: see text]O2 slow component was significantly greater at 50 r·min-1 than at 90 r·min-1 (LO: 0.60 ± 0.30 vs. HI: 0.47 ± 0.21 L·min-1; p < 0.05). The mean value for the localized rating of perceived exertion was also higher at 50 r·min-1 than at 90 r·min-1 (LO: 16.7 ± 1.4 vs. HI: 15.2 ± 1.3; p < 0.05), but there was no significant difference in end-exercise blood lactate concentration. It is possible that differences in muscle tension development and blood flow resulted in a greater contribution of "low-efficiency" type II muscle fibres to force production at the lower crank rate in ACE, and that this was linked to the greater [Formula: see text]O2 slow component. However, other factors such as greater isometric contraction of the muscles of the trunk and legs at the lower crank rate might also be implicated.Key words: O2 kinetics, [Formula: see text]O2 slow component, fibre recruitment, oxygen uptake.

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