Physiological Features of Puberty of Children in Conditions of Increased Physical Loads

Abstract

The article presents the results of a comprehensive study of the daily excretion of cortisol (free and bound), 17-keto steroids and the state of hemodynamics in young hockey players of 11-15 years taking into account the stages of puberty, as well as their comparative characteristics with performance in control class boys engaged in physical culture in the volume of the comprehensive school. It is shown that at the I-IV stages of puberty observed consistently high urinary free cortisol, was significantly higher than in the control class boys, and from IV to V stage - simultaneous and significant decrease in all studied parameters of the functional state of the adrenal cortex was noted. The I and II stage of the puberty in athletes are characterized by maximum values of the heart rate, cardiac output, and diastolic blood pressure values, and their subsequent reduction to stage III, in this case from IV to V stage of puberty there is a significant increase in peripheral vascular resistance. In contrast, in children who are not involved in sports, pubertal changes in the state of hemodynamics have opposite directions. Thus the adaptive responses of the physiological systems in young athletes prevail over evolutionary processes associated with the puberty.