Maturity-Associated Variations in Resistance Exercise-Induced Hormonal Responses in Young Male Athletes

PURPOSE: To examine differences in resistance exercise-induced hormonal responses among young athletes according to their maturity levels. MATERIALS AND METHODS: A total of 12 collegiate and 32 junior high school male athletes were enrolled. The junior high school participants were divided into pre-peak height velocity (PHV) and post-PHV groups, according to their PHV ages. The salivary testosterone, cortisol, and human growth hormone levels were analyzed before (pre), immediately after (post), and at 15 minutes after performing body weight resistance exercise. RESULTS: The testosterone levels were higher in the collegiate than in the junior high school group (P < .01) and increased after 15 minutes of exercise (P < .01). A significant decrease in the cortisol levels postexercise in the junior high school groups (P < .01) and an increase in the human growth hormone levels at 15 minutes after exercise in the post-PHV group were observed (P < .01). In the collegiate and post-PHV groups, the testosterone-to-cortisol ratio increased post and at 15 minutes after exercise (P < .01). The testosterone-to-cortisol ratio values were higher in the collegiate than in the post-PHV (at preexercise and at 15 min after [P < .01]) and pre-PHV groups (at all times [P < .01]). CONCLUSION: Exercise-induced acute hormonal responses to resistance exercise may depend on individuals' maturity levels, even in those having the same age.