Oxygen uptake kinetics in trained adolescent females

Abstract

Little evidence exists with regard to the effect that exercise training has upon oxygen uptake kinetics in adolescent females. PURPOSE: The aim of the study was to compare 2 o V  and muscle deoxygenation kinetics in a group of trained (Tr) and untrained (Utr) female adolescents. METHOD: Twelve trained (6.4 ± 0.9 years training, 10.3 ± 1.4 months per year training, 5.2 ± 2.0 hours per week) adolescent female soccer players (Age: 14.6 ± 0.7 years) were compared to a group (n=8) of recreationally active adolescent girls (Age: 15.1 ± 0.6 years) of similar maturity status. Subjects underwent two, 6-min exercise transitions at a workload equivalent to 80% of lactate threshold from a 3-min baseline of 10W. All subjects had a passive rest period of 1 hour between each square-wave transition. Breath-by-breath oxygen uptake and muscle deoxygenation were measured throughout and were modelled via a monoexponential decay with a delay relative to the start of exercise. RESULT: Peak 2 o V  was significantly (p<0.05) greater in the Tr compared to the Utr (Tr: 43.2 ± 3.2 mL·kg -1 min -1 vs. Utr: 34.6 ± 4.0 mL·kg -1 min -1 ). The 2 o V  time constant was significantly (p<0.05) faster in the Tr compared to the Utr (Tr: 26 .3 ± 6.9 s vs. Utr: 35.1 ± 11.5 s). There was no inter-group difference in the time constant for muscle deoxygenation kinetics (Tr: 8.5 ± 3.0 s vs. Utr: 12.4 ± 8.3 s); a large effect size, however, was demonstrated (-0.804). CONCLUSION: Exercise training and/or genetic self-selection results in faster kinetics in trained adolescent females. The faster 2 o V  kinetics seen in the trained group may result from enhanced muscle oxygen utilisation.

Assessing Differences in Cardiorespiratory Fitness With Respect to Maturity Status in Highly Trained Youth Soccer Players

“…With faster taus relating to a greater volume and an improved ability to maintain high speed activities during youth soccer match-play. Furthermore, research into adolescent male and female soccer players has demonstrated faster VO kinetics in soccer trained individuals in comparison to their untrained counterparts (29,37). Current results also support previous research which highlights faster taus in younger populations, with such measures becoming progressively slower (i.e.…”

Oxygen Uptake Kinetics in Youth: Characteristics, Interpretation, and Application

“…However, it was also suggested that these findings may reflect the presence of a maturational threshold below which a significant physiological response to training was not manifest (61). In contrast to this notion and the earlier studies, more recent, methodologically rigorous, studies report a significant influence of training status on the V  O2 kinetics of both prepubertal children (80,112) and pubertal adolescents (78,81,104), although these differences were still restricted to the temporal parameters with no influence of the magnitude of the V  O2 slow component. Perhaps surprisingly given the relevance to training guidelines and performance (33), no studies have directly addressed the question of sex differences in the response of V  O2 kinetics to training.…”

Influence of high-intensity interval training in adolescents with asthma

“…Specifically, a faster V̇O2 kinetic time constant was reported in trained compared to untrained children (Winlove et al, 2010) with no differences found in two other studies (Cleuziou et al, 2002, Obert et al, 2000. Adolescent studies have, however, found training to be associated with a faster V̇O2 kinetic time constant (Marwood et al, 2010, McNarry et al, 2011c, Unnithan et al, 2015. A faster V̇O2 kinetic time constant was also observed following a 6-week High-Intensity Interval Training (HIIT) intervention in obese children (McNarry et al, 2015b), though it is noteworthy that no influence of HIIT was found in the normal weight children.…”

“…Indeed, in pre-pubertal children, Winlove et al (2010) reported a faster V̇O2 kinetic time constant in trained swimmers in comparison to their untrained peers, whilst in contrast, two studies reported no difference between trained and untrained pre-pubertal children (Cleuziou et al, 2002, Obert et al, 2000. Moreover, in adolescents, training was associated with a faster V̇O2 kinetic time constant than their untrained peers (Marwood et al, 2010, McNarry et al, 2011c, Unnithan et al, 2015. The conflicting results may be explained by different modalities between training and experimental measures.…”

“…Previously [HHb] and HR kinetics have been used to assess the differences between trained and untrained adolescents in soccer and swimming (Marwood et al, 2010, McNarry et al, 2011c, Unnithan et al, 2015. The two studies in soccer compared responses to moderate-intensity exercise in trained and untrained participants and found the trained participants to have a significantly faster V̇O2 kinetic response (Marwood et al, 2010, Unnithan et al, 2015 et al, , Poole et al, 2008. In addition, although cross-sectional studies provide an informative comparison of training effects, they are unable to distinguish between genetic selection and an actual training effect.…”