A Single Bout of Constant-Load Exercise Test for Estimating the Time Constant of Oxygen Uptake Kinetics in Individuals With Stroke

Objective To examine the relationship between the time constant of oxygen uptake kinetics during the onset of exercise (τVO2) estimated from a single exercise bout and that obtained from three averaged exercise bouts in individuals with stroke.Methods Twenty participants with stroke performed three bouts of a constant-load pedaling exercise at approximately 80% of the workload corresponding to the ventilatory threshold to estimate τVO2. The VO2 data from the first trial of three bouts were used to estimate τVO2 for a single bout. Additionally, data collected from three bouts were ensemble-averaged to obtain τVO2 for three averaged bouts as the criterion.Results There was a very high correlation between τVO2 for a single bout (34.8±14.0 seconds) and τVO2 for three averaged bouts (38.5±13.4 seconds) (r=0.926, p<0.001). However, τVO2 for a single bout was smaller than that for three averaged bouts (p=0.006).Conclusion τVO2 for a single bout could reflect the relative difference in τVO2 for three averaged bouts among individuals with stroke. However, it should be noted that τVO2 for a single bout may be underestimated compared to τVO2 for three averaged bouts.

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Gymnasium-based unsupervised exercise maintains benefits in oxygen uptake kinetics obtained following supervised training in type 2 diabetes

Applied Physiology Nutrition and Metabolism ◽

10.1139/h2012-012 ◽

2012 ◽

Vol 37 (4) ◽

pp. 599-609 ◽

Cited By ~ 7

Author(s):

Oscar MacAnaney ◽

Donal O’Shea ◽

Stuart A. Warmington ◽

Simon Green ◽

Mikel Egaña

Keyword(s):

Type 2 Diabetes ◽

Heart Rate ◽

Oxygen Uptake ◽

Ventilatory Threshold ◽

Constant Load ◽

Oxygen Uptake Kinetics ◽

Uptake Kinetics ◽

Supervised Exercise ◽

Rate Kinetics

Supervised exercise (SE) in patients with type 2 diabetes improves oxygen uptake kinetics at the onset of exercise. Maintenance of these improvements, however, has not been examined when supervision is removed. We explored if potential improvements in oxygen uptake kinetics following a 12-week SE that combined aerobic and resistance training were maintained after a subsequent 12-week unsupervised exercise (UE). The involvement of cardiac output (CO) in these improvements was also tested. Nineteen volunteers with type 2 diabetes were recruited. Oxygen uptake kinetics and CO (inert gas rebreathing) responses to constant-load cycling at 50% ventilatory threshold (VT), 80% VT, and mid-point between VT and peak workload (50% Δ) were examined at baseline (on 2 occasions) and following each 12-week training period. Participants decided to exercise at a local gymnasium during the UE. Thirteen subjects completed all the interventions. The time constant of phase 2 of oxygen uptake was significantly faster (p < 0.05) post-SE and post-UE compared with baseline at 50% VT (17.3 ± 10.7 s and 17.5 ± 5.9 s vs. 29.9 ± 10.7 s), 80% VT (18.9 ± 4.7 and 20.9 ± 8.4 vs. 34.3 ± 12.7s), and 50% Δ (20.4 ± 8.2 s and 20.2 ± 6.0 s vs. 27.6 ± 3.7 s). SE also induced faster heart rate kinetics at all 3 intensities and a larger increase in CO at 30 s in relation to 240 s at 80% VT; and these responses were maintained post-UE. Unsupervised exercise maintained benefits in oxygen uptake kinetics obtained during a supervised exercise in subjects with diabetes, and these benefits were associated with a faster dynamic response of heart rate after training.

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Oxygen Uptake Kinetics in Endurance Trained Youth and Adult Cyclists

Journal of Sports Science and Medicine ◽

10.52082/jssm.2021.398 ◽

2021 ◽

pp. 398-403

Author(s):

Bernhard Prinz ◽

Manfred Zöger ◽

Harald Tschan ◽

Alfred Nimmerichter

Keyword(s):

Oxygen Uptake ◽

Time Constant ◽

Oxygen Uptake Kinetics ◽

Primary Response ◽

Uptake Kinetics ◽

Repeated Measure ◽

Adult Age ◽

Mean Response Time ◽

Training History ◽

Rate Intensity

Previous studies reported faster pulmonary oxygen uptake kinetics at the onset of exercise in untrained youth compared with adults. Whether or not these differences are identical for trained groups have not been examined. The purpose of this study was to compare ̇VO2 kinetics of youth and adult cyclists at moderate and heavy-intensity exercise. Thirteen adult (age: 23.2 ± 4.8 years; ̇VO2peak 68.4 ± 6.8 mL·min-1.kg-1) and thirteen youth cyclists (age: 14.3 ± 1.5 years; ̇VO2peak 61.7 ± 4.3 mL·min-1.kg-1) completed a series of 6-min square wave exercises at moderate and heavy-intensity exercise at 90 rev·min-1. A two-way repeated-measure ANOVA was conducted to identify differences between groups and intensities. The time constant, time delay and the mean response time were not significantly different between youth and adult cyclists (p > 0.05). We found significant differences between intensities, with a faster time constant during moderate than heavy-intensity exercise in youth (24.1 ± 7.0 s vs. 31.8 ± 5.6 s; p = 0.004) and adults (22.7 ± 5.6 s vs. 28.6 ± 5.7 s; p < 0.001). The present data suggest that the effect of training history in adult cyclists compensate for the superior primary response of the oxygen uptake kinetics typically seen in youth compared to adults. Furthermore, the ̇VO2 response is dependent of work rate intensity in trained youth and adult cyclists.

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Oxygen uptake kinetics for various intensities of constant-load work.

Journal of Applied Physiology ◽

10.1152/jappl.1972.33.3.351 ◽

1972 ◽

Vol 33 (3) ◽

pp. 351-356 ◽

Cited By ~ 407

Author(s):

B J Whipp ◽

K Wasserman

Keyword(s):

Oxygen Uptake ◽

Constant Load ◽

Oxygen Uptake Kinetics ◽

Uptake Kinetics

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Cardiovascular and Oxygen Uptake Kinetics During Sequential Heavy Cycling Exercises

Canadian Journal of Applied Physiology ◽

10.1139/h03-022 ◽

2003 ◽

Vol 28 (2) ◽

pp. 283-298 ◽

Cited By ~ 23

Author(s):

Stéphane Perrey ◽

Jodie Scott ◽

Laurent Mourot ◽

Jean-Denis Rouillon

Keyword(s):

Cardiac Output ◽

Oxygen Uptake ◽

Time Constant ◽

Impedance Cardiography ◽

Ventilatory Threshold ◽

Slow Component ◽

Oxygen Uptake Kinetics ◽

Cycle Ergometer ◽

Fast Component ◽

Heavy Exercise

The purpose of the present study was to assess the relationship between the rapidity of increased oxygen uptake [Formula: see text] and increased cardiac output (CO) during heavy exercise. Six subjects performed repeated bouts on a cycle ergometer above the ventilatory threshold (∼80% of peak [Formula: see text]) separated by 10-min recovery cycling at 35% peak [Formula: see text]. [Formula: see text] was determined breath-by-breath and CO was determined continuously by impedance cardiography. CO and [Formula: see text] values were significantly higher during the 2-min period preceding the second bout. The overall responses for [Formula: see text] and CO were significantly related and were faster during the second bout. Prior heavy exercise resulted in a significant increase in the amplitude of the fast component of [Formula: see text] with no change in the time constant and a decrease in the slow component. Under these circumstances, the amplitude of the fast component was more sensitive to prior heavy exercise than was the associated time constant. Key words: impedance cardiography, exercise transitions, cardiac output, prior exercise

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The relationship between oxygen uptake kinetics and neuromuscular fatigue in high-intensity cycling exercise

European Journal of Applied Physiology ◽

10.1007/s00421-017-3585-1 ◽

2017 ◽

Vol 117 (5) ◽

pp. 969-978 ◽

Cited By ~ 16

Author(s):

John Temesi ◽

Felipe Mattioni Maturana ◽

Arthur Peyrard ◽

Tatiane Piucco ◽

Juan M. Murias ◽

...

Keyword(s):

Oxygen Uptake ◽

High Intensity ◽

Oxygen Uptake Kinetics ◽

Neuromuscular Fatigue ◽

Uptake Kinetics ◽

Cycling Exercise ◽

The Relationship

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Influence of menopause and Type 2 diabetes on pulmonary oxygen uptake kinetics and peak exercise performance during cycling

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00258.2015 ◽

2015 ◽

Vol 309 (8) ◽

pp. R875-R883 ◽

Cited By ~ 6

Author(s):

Catherine Kiely ◽

Joel Rocha ◽

Eamonn O'Connor ◽

Donal O'Shea ◽

Simon Green ◽

...

Keyword(s):

Type 2 Diabetes ◽

Oxygen Uptake ◽

Ventilatory Threshold ◽

Menopausal Status ◽

Constant Load ◽

Peak Oxygen Uptake ◽

Oxygen Uptake Kinetics ◽

Peak Exercise ◽

Age Range

We investigated if the magnitude of the Type 2 diabetes (T2D)-induced impairments in peak oxygen uptake (V̇o2) and V̇o2 kinetics was affected by menopausal status. Twenty-two women with T2D (8 premenopausal, 14 postmenopausal), and 22 nondiabetic (ND) women (11 premenopausal, 11 postmenopausal) matched by age (range = 30–59 yr) were recruited. Participants completed four bouts of constant-load cycling at 80% of their ventilatory threshold for the determination of V̇o2 kinetics. Cardiac output (CO) (inert gas rebreathing) was recorded at rest and at 30 s and 240 s during two additional bouts. Peak V̇o2 was significantly ( P < 0.05) reduced in both groups with T2D compared with ND counterparts (premenopausal, 1.79 ± 0.16 vs. 1.55 ± 0.32 l/min; postmenopausal, 1.60 ± 0.30 vs. 1.45 ± 0.24 l/min). The time constant of phase II of the V̇o2 response was slowed ( P < 0.05) in both groups with T2D compared with healthy counterparts (premenopausal, 29.1 ± 11.2 vs. 43.0 ± 12.2 s; postmenopausal, 33.0 ± 9.1 vs. 41.8 ± 17.7 s). At rest and during submaximal exercise absolute CO responses were lower, but the “gains” in CO larger (both P < 0.05) in both groups with T2D. Our results suggest that the magnitude of T2D-induced impairments in peak V̇o2 and V̇o2 kinetics is not affected by menopausal status in participants younger than 60 yr of age.

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Similar level of impairment in exercise performance and oxygen uptake kinetics in middle-aged men and women with type 2 diabetes

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00012.2012 ◽

2012 ◽

Vol 303 (1) ◽

pp. R70-R76 ◽

Cited By ~ 29

Author(s):

Eamonn O'Connor ◽

Catherine Kiely ◽

Donal O'Shea ◽

Simon Green ◽

Mikel Egaña

Keyword(s):

Type 2 Diabetes ◽

Oxygen Uptake ◽

Ventilatory Threshold ◽

Constant Load ◽

Peak Oxygen Uptake ◽

Oxygen Uptake Kinetics ◽

Dynamic Responses ◽

Middle Aged ◽

Men And Women

The present study tested the hypothesis that the magnitude of the type 2 diabetes-induced impairments in peak oxygen uptake (V̇o2) and V̇o2 kinetics would be greater in females than males in middle-aged participants. Thirty-two individuals with type 2 diabetes (16 male, 16 female), and 32 age- and body mass index (BMI)-matched healthy individuals (16 male, 16 female) were recruited. Initially, the ventilatory threshold (VT) and peak V̇o2 were determined. On a separate day, subjects completed four 6-min bouts of constant-load cycling at 80% VT for the determination of V̇o2 kinetics using standard procedures. Cardiac output (CO) (inert gas rebreathing) was recorded at rest, 30, and 240 s during two additional bouts. Peak V̇o2 (ml·kg−1·min−1) was significantly reduced in men and women with type 2 diabetes compared with their respective nondiabetic counterparts (men, 27.8 ± 4.4 vs. 31.1 ± 6.2 ml·kg−1·min−1; women, 19.4 ± 4.1 vs. 21.4 ± 2.9 ml·kg−1·min−1). The time constant (s) of phase 2 (τ2) and mean response time (s) of the V̇o2 response (MRT) were slowed in women with type 2 diabetes compared with healthy women (τ2, 43.3 ± 9.8 vs. 33.6 ± 10.0 s; MRT, 51.7 ± 9.4 vs. 43.5 ± 11.4s) and in men with type 2 diabetes compared with nondiabetic men (τ2, 43.8 ± 12.0 vs. 35.3 ± 9.5 s; MRT, 57.6 ± 8.3 vs. 47.3 ± 9.3 s). The magnitude of these impairments was not different between males and females. The steady-state CO responses or the dynamic responses of CO were not affected by type 2 diabetes among men or women. The results suggest that the type 2 diabetes-induced impairments in peak V̇o2 and V̇o2 kinetics are not affected by sex in middle aged participants.

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On issues of confidence in determining the time constant for oxygen uptake kinetics * Commentary

British Journal of Sports Medicine ◽

10.1136/bjsm.2003.004721 ◽

2004 ◽

Vol 38 (5) ◽

pp. 553-560 ◽

Cited By ~ 22

Author(s):

G H Markovitz

Keyword(s):

Oxygen Uptake ◽

Time Constant ◽

Oxygen Uptake Kinetics ◽

Uptake Kinetics

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The Relationship Between Repeated‐Sprint Ability, Aerobic Capacity, and Oxygen Uptake Recovery Kinetics in Female Soccer Athletes

Journal of Human Kinetics ◽

10.2478/hukin-2020-0042 ◽

2020 ◽

Vol 75 (1) ◽

pp. 115-126

Author(s):

Bruno Archiza ◽

Daniela K. Andaku ◽

Thomas Beltrame ◽

Cleiton A. Libardi ◽

Audrey Borghi-Silva

Keyword(s):

Oxygen Uptake ◽

Aerobic Capacity ◽

Female Athletes ◽

Oxygen Uptake Kinetics ◽

Uptake Kinetics ◽

Time To Exhaustion ◽

Repeated Sprint Ability ◽

Repeated Sprint ◽

The Relationship ◽

Sprint Ability

Abstract This study investigated the relationship between repeated-sprint ability, aerobic capacity, and oxygen uptake kinetics during the transition between exercise and recovery (off-transient) in female athletes of an intermittent sport modality. Eighteen professional soccer players completed three tests: 1) a maximal incremental exercise test; 2) a constant speed time-to-exhaustion test; and 3) a repeated-sprint ability test consisting of six 40-m sprints with 20 s of passive recovery in-between. Correlations between time-to-exhaustion, repeated-sprint ability, and oxygen uptake kinetics were calculated afterwards. The level of significance was set at p < 0.05. A performance decrement during repeated-sprint ability was found to be related to: 1) time-to-exhaustion (e.g., exercise tolerance; r = -0.773, p < 0.001); 2) oxygen uptake recovery time (r = 0.601, p = 0.008); and 3) oxygen uptake mean response time of recovery (r = 0.722, p < 0.001). Moreover, the best sprint time (r = -0.601, p = 0.008) and the mean sprint time (r = -0.608, p = 0.007) were found to be related to maximal oxygen uptake. Collectively, these results reinforce the relation between oxygen uptake kinetics and the ability to maintain sprint performance in female athletes. These results may contribute to coaches and training staff of female soccer teams to focus on training and improve their athletes’ aerobic capacity and recovery capacity to improve intermittent exercise performance.

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