scholarly journals The effect of priming exercise on O2 uptake kinetics, muscle O2 delivery and utilization, muscle activity, and exercise tolerance in boys

2014 ◽  
Vol 39 (3) ◽  
pp. 308-317 ◽  
Author(s):  
Alan R. Barker ◽  
Emily Trebilcock ◽  
Brynmor Breese ◽  
Andrew M. Jones ◽  
Neil Armstrong
Keyword(s):  
Oxygen Uptake ◽  
Phase Ii ◽  
Muscle Activity ◽  
Oxygen Delivery ◽  
Exercise Tolerance ◽  
Slow Component ◽  
Oxygen Uptake Kinetics ◽  
Uptake Kinetics ◽  
Muscle Oxygen ◽  
Priming Exercise

This study used priming exercise in young boys to investigate (i) how muscle oxygen delivery and oxygen utilization, and muscle activity modulate oxygen uptake kinetics during exercise; and (ii) whether the accelerated oxygen uptake kinetics following priming exercise can improve exercise tolerance. Seven boys that were aged 11.3 ± 1.6 years completed either a single bout (bout 1) or repeated bouts with 6 min of recovery (bout 2) of very heavy-intensity cycling exercise. During the tests oxygen uptake, muscle oxygenation, muscle electrical activity and exercise tolerance were measured. Priming exercise most likely shortened the oxygen uptake mean response time (change, ±90% confidence limits; –8.0 s, ±3.0), possibly increased the phase II oxygen uptake amplitude (0.11 L·min−1, ±0.09) and very likely reduced the oxygen uptake slow component amplitude (–0.08 L·min−1, ±0.07). Priming resulted in a likely reduction in integrated electromyography (–24% baseline, ±21% and –25% baseline, ±19) and a very likely reduction in Δ deoxyhaemoglobin/Δoxygen uptake (–0.16, ±0.11 and –0.09, ±0.05) over the phase II and slow component portions of the oxygen uptake response, respectively. A correlation was present between the change in tissue oxygenation index during bout 2 and the change in the phase II (r = –0.72, likely negative) and slow component (r = 0.72, likely positive) oxygen uptake amplitudes following priming exercise, but not for muscle activity. Exercise tolerance was likely reduced (change –177 s, ±180) following priming exercise. The altered phase II and slow component oxygen uptake amplitudes in boys following priming exercise are linked to an improved localised matching of muscle oxygen delivery to oxygen uptake and not muscle electrical activity. Despite more rapid oxygen uptake kinetics following priming exercise, exercise tolerance was not enhanced.

scholarly journals Pulmonary O2 uptake on-kinetics in sprint- and endurance-trained athletes

2007 ◽  
Vol 32 (3) ◽  
pp. 383-393 ◽  
Author(s):  
Nicolas J.A. Berger ◽  
Andrew M. Jones
Keyword(s):  
Oxygen Uptake ◽  
Phase Ii ◽  
Exercise Performance ◽  
Slow Component ◽  
Oxygen Uptake Kinetics ◽  
Uptake Kinetics ◽  
Anaerobic Exercise ◽  
Moderate Intensity ◽  
Peak Power Output ◽  
Severe Intensity

Pulmonary O2 uptake kinetics during “step” exercise have not been characterized in young, sprint-trained (SPT), athletes. Therefore, the objective of this study was to test the hypotheses that SPT athletes would have (i) slower phase II kinetics and (ii) a greater oxygen uptake “slow component” when compared with endurance-trained (ENT) athletes. Eight sub-elite SPT athletes (mean ( ± SD) age = 25 (±7) y; mass = 80.3 (±7.3) kg) and 8 sub-elite ENT athletes (age= 28 (±4) y; mass = 73.2 (±5.1) kg) completed a ramp incremental cycle ergometer test, a Wingate 30 s anaerobic sprint test, and repeat “step” transitions in work rate from 20 W to moderate- and severe-intensity cycle exercise, during which pulmonary oxygen uptake was measured breath by breath. The phase II oxygen uptake kinetics were significantly slower in the SPT athletes both for moderate (time constant, τ; SPT 32 (±4) s vs. ENT 17 (±3) s; p < 0.01) and severe (SPT 32 (±12) s vs. ENT 20 (±6) s; p < 0.05) exercise. The amplitude of the slow component (derived by exponential modelling) was not significantly different between the groups (SPT 0.55 (±0.12) L·min–1 vs. ENT 0.50 (±0.22) L·min–1), but the increase in oxygen uptake between 3 and 6 min of severe exercise was greater in the SPT athletes (SPT 0.37 (±0.08) L·min–1 vs. ENT 0.20 (±0.09) L·min–1; p < 0.01). The phase II τ was significantly correlated with indices of aerobic exercise performance (e.g., peak oxygen uptake (moderate-intensity r = –0.88, p < 0.01; severe intensity r = –0.62; p < 0.05), whereas the relative amplitude of the oxygen uptake slow component was significantly correlated with indices of anaerobic exercise performance (e.g., Wingate peak power output; r = 0.77; p < 0.01). Thus, it could be concluded that sub-elite SPT athletes have slower phase II oxygen uptake kinetics and a larger oxygen uptake slow component compared with sub-elite ENT athletes. It appears that indices of aerobic and anaerobic exercise performance differentially influence the fundamental and slow components of the oxygen uptake kinetics.

Sodium bicarbonate ingestion does not alter the slow component of oxygen uptake kinetics in professional cyclists

2003 ◽  
Vol 21 (1) ◽  
pp. 39-47 ◽  
Author(s):  
ALFREDO SANTALLA ◽  
MARGARITA PÉREZ ◽  
MANUEL MONTILLA ◽  
LÁZARO VICENTE ◽  
RICHARD DAVISON ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Sodium Bicarbonate ◽  
Slow Component ◽  
Oxygen Uptake Kinetics ◽  
Uptake Kinetics

Phase I and Phase II Oxygen Uptake Kinetics During Atrioventricular Dyssynchrony in Chronotropically Competent Pacemaker Patients

CHEST Journal ◽  
2005 ◽  
Vol 128 (3) ◽  
pp. 1782-1789 ◽  
Author(s):  
Corey R. Tomczak ◽  
Wladyslaw Wojcik ◽  
Edward F.G. Busse ◽  
Robert G. Haennel
Keyword(s):  
Oxygen Uptake ◽  
Phase I ◽  
Phase Ii ◽  
Oxygen Uptake Kinetics ◽  
Uptake Kinetics

The effects of intensity on V̇O2 kinetics during incremental free swimming

2015 ◽  
Vol 40 (9) ◽  
pp. 918-923 ◽  
Author(s):  
Kelly de Jesus ◽  
Ana Sousa ◽  
Karla de Jesus ◽  
João Ribeiro ◽  
Leandro Machado ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Slow Component ◽  
Metabolic Stress ◽  
Relevant Information ◽  
Oxygen Uptake Kinetics ◽  
Uptake Kinetics ◽  
Uptake Kinetic ◽  
Performance Diagnosis ◽  
Incremental Protocol ◽  
And Training

Swimming and training are carried out with wide variability in distances and intensities. However, oxygen uptake kinetics for the intensities seen in swimming has not been reported. The purpose of this study was to assess and compare the oxygen uptake kinetics throughout low-moderate to severe intensities during incremental swimming exercise. We hypothesized that the oxygen uptake kinetic parameters would be affected by swimming intensity. Twenty male trained swimmers completed an incremental protocol of seven 200-m crawl swims to exhaustion (0.05 m·s−1 increments and 30-s intervals). Oxygen uptake was continuously measured by a portable gas analyzer connected to a respiratory snorkel and valve system. Oxygen uptake kinetics was assessed using a double exponential regression model that yielded both fast and slow components of the response of oxygen uptake to exercise. From low-moderate to severe swimming intensities changes occurred for the first and second oxygen uptake amplitudes (P ≤ 0.04), time constants (P = 0.01), and time delays (P ≤ 0.02). At the heavy and severe intensities, a notable oxygen uptake slow component (>255 mL·min−1) occurred in all swimmers. Oxygen uptake kinetics whilst swimming at different intensities offers relevant information regarding cardiorespiratory and metabolic stress that might be useful for appropriate performance diagnosis and training prescription.

scholarly journals Cocoa-flavanols enhance moderate-intensity pulmonary V̇O2 kinetics but not exercise tolerance in sedentary middle-aged adults: A randomised controlled trial

2020 ◽  
Author(s):  
Daniel Sadler ◽  
Richard Draijer ◽  
Claire E. Stewart ◽  
Helen Jones ◽  
Simon Marwood ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Exercise Tolerance ◽  
Oxygen Uptake Kinetics ◽  
Uptake Kinetics ◽  
Moderate Intensity ◽  
Moderate Activity ◽  
Middle Aged ◽  
Severe Intensity ◽  
Middle Aged Adults ◽  
Cocoa Flavanols

Abstract Background: Cocoa flavanols (CF) may exert health benefits through their potent vasodilatory effects which are perpetuated by elevations in nitric oxide (NO) bioavailability. These vasodilatory effects may contribute to improved delivery of blood and oxygen to exercising muscle.Objective: Therefore, the objective of this study was to examine how CF supplementation impacts pulmonary oxygen uptake (V̇O2) kinetics and exercise tolerance in sedentary middle-aged adults.Methods: We employed a double-blind cross-over, placebo-controlled design whereby 17 participants (11 male, 6 female; mean±SD, 45±6 years) randomly received either 7 days of daily CF (400 mg) or placebo (PL) supplementation. On day 7, participants completed a series of ‘step’ moderate- and severe-intensity exercise tests for the determination of oxygen uptake kinetics.Results: During moderate-intensity exercise, the time constant of the fundamental phase of V̇O2 kinetics (τV̇O2) was decreased by 15% in CF as compared to PL (mean±SD; PL: 40±12 vs. CF: 34±9 s, P=0.019), with no differences in the amplitude of V̇O2 (AV̇O2; PL: 0.77±0.32 vs. CF: 0.79±0.34 l min−1, P=0.263). However, during severe-intensity exercise, τV̇O2,the amplitude of the slow component (SCV̇O2) and exercise tolerance (PL: 435±58 vs. CF: 424±47 s, P=0.480) were unchanged between conditions.Conclusions: Our data show that acute CF supplementation enhanced oxygen uptake kinetics during moderate-, but not severe-intensity exercise in middle-aged participants. These novel effects of CFs, in this demographic, may contribute to improved tolerance of moderate-activity physical activities, which appear commonly present in daily life.Registered under ClinicalTrials.gov Identifier no. NCT04370353

scholarly journals Limitations to exercise tolerance in type 1 diabetes: the role of pulmonary oxygen uptake kinetics and priming exercise

2020 ◽  
Vol 128 (5) ◽  
pp. 1299-1309
Author(s):  
Richie P. Goulding ◽  
Denise M. Roche ◽  
Sam N. Scott ◽  
Shunsaku Koga ◽  
Philip J. Weston ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Oxygen Uptake ◽  
Exercise Tolerance ◽  
Oxygen Uptake Kinetics ◽  
Muscle Deoxygenation ◽  
Prior Exercise ◽  
Healthy Control ◽  
Priming Exercise

Patients with type 1 diabetes demonstrated slower oxygen uptake (V̇o2) kinetics compared with healthy control subjects. Furthermore, a prior bout of high-intensity exercise speeded V̇o2 kinetics and increased critical power in people with type 1 diabetes. Prior exercise speeded muscle deoxygenation kinetics, indicating that V̇o2 kinetics in type 1 diabetes are limited primarily by oxygen extraction and/or intracellular factors. These findings highlight the potential for interventions that decrease metabolic inertia for enhancing exercise tolerance in this condition.

Sign in / Sign up

Export Citation Format

Share Document