PUBERTAL STAGE DIFFERENCES IN HORMONAL AND HEMATOLOGICAL RESPONSES TO MAXIMAL EXERCISE IN MALES

Concentrations of serum testosterone (ST), growth hormone (SGH), and insulin (SI) at rest and following maximal exercise were compared in 27 males in different stages of pubertal development. Oxygen consumption and heart rate were measured while subjects performed a continous-incremental work capacity test to voluntary cessation on a cycle ergometer. Pre- and postexercise blood samples were analyzed for hemoglobin (Hb) and hematocrit (Hct) by Coulter Counter, and for ST, SGH, and SI by radioimmunoassay. ST at rest increased with pubertal stage and was related to the increase in body weight and work capacity seen with increasing development during adolescence. There were no differences between pubertal stages in changes in hormone concentrations following exercise or in Hct or Hb before or after exercise. Our results do not support the hypothesis of a critical pubertal stage that exhibits enhanced response to exercise.