Objective: The study is to test the serum testosterone level of young swimmers at different pubertal stages in Shanghai, and to compare the difference of serum testosterone concentration at every stage, and to investigate the feasibility of using different adolescent pubertal stages to predict serum testosterone concentration. Methods: The left hands were X-rayed and the serum testosterone concentrations were tested among 420 young swimmers. The swimmers were divided into groups according to different seed bone morphology in bone age film, and then 30 athletes were selected randomly from each group as the subjects. Serum testosterone levels were compared among final groups of male and female athletes respectively. Results: There were significant differences in serum testosterone concentration at different pubertal stages between male and female athletes (P<0.01). The serum testosterone level of male athletes at the post-development stage was 186% and 1187% of those during and before development respectively, and 155% and 329% for females. The testosterone level of male athletes was positively correlated with muscle mass (r=0.875, P<0.01), negatively correlated with body fat percentage (r=-0.312, P<0.01), but both positively correlated for female athletes (r=0.774 and 0.463, P<0.01). Conclusion: The serum testosterone concentration of male and female swimmers in the whole pubertal stage has a significant increasing trend, and the serum testosterone has obvious change at each stage of growth and development. Serum testosterone level has an impact on the body composition for both male and female athletes, and has gender differences as well. |