Abstract

In order to investigate the effects of training on testosterone in the young, serum testosterone was compared in eight intensively trained male gymnasts (mean age = 10.9 yr) and 11 similarly aged controls (mean age = 11.1 yr). After a 5-day rest, gymnasts resumed normal training when finger puncture blood samples were collected before training (PRE), after training (POST) and 30 min later (REC) on four days. On three of these days blood was also taken from controls at PRE and REC times. Repeated measures MANOVA with planned comparisons revealed significant differences between groups for skeletal age (mean = 9.6 yr GYM, mean = 11.4 yr CONTROL) while there was no difference between groups for resting serum testosterone. PRE levels of testosterone for gymnasts were significantly lower on days 2, 3 and 4 than for the same time on day 1. It was concluded that resting serum testosterone levels are reduced by the training regime followed by the boys in the current work and in a pattern similar to that reported for exercising adults by others. Furthermore, it was speculated that the retarded skeletal age seen on x-ray examination of the gymnasts might reflect in part local mechanical effects of training. Verf.-Referat