This study was designed to investigate the influence of sexual maturity on peak V̇O2 and blood lactate responses to exercise using serum testosterone levels as an objective measure of maturity. Testosterone levels were determined in venous blood samples obtained from 12- to 16-year-old males (n = 50). Peak V̇O2 and percentage of peak V̇O2 at blood lactate levels of 2.5 and 4.0 mmol·L−1 were determined during incremental treadmill running. Standard multiple regression revealed that body mass, age, and height explained 74% of the variance in peak V̇O2 scores. The addition of serum testosterone to the equation failed to produce a significant increase in the explained variance. Correlation coefficients between testosterone and the lactate variables were not significant (p > .05). These findings do not support the hypothesis that hormonal changes per se during sexual maturation play an important role in the development of peak V̇O2 and blood lactate responses to exercise.
The authors are with the PEA Research Centre at the University of Exeter, Heavitree Road, Exeter EX1 2LU, UK.