Učënye Zapiski Kazanskogo Universiteta. Seriâ Estestvennye Nauki (Dec 2018)
The role of hormones of the adrenal cortex in regulation of the muscular activity of a growing organism
Abstract
We studied the endocrine mechanisms of urgent and long-term adaptation of children to increased physical stresses and, in particular, the role of hormones of the adrenal cortex in the regulation of the muscular activity of male athletes aged 11–15 years old. The relevance of the study is determined by the immaturity and functional instability of the hypothalamic-pituitary-adrenal system in children, its physiological hyperfunction during the adolescent period, which, when exposed to high muscular loadings, increases the risk of evolutionary processes transition to the endocrine dysfunction of adolescence. However, in most studies, the secretory activity of adrenal cortex is considered only as an indicator of fitness. The age-related dynamics of glucocorticoid and androgenic function of adrenal cortex in 11–15-year-old boys engaged in hockey, the degree of their participation in the process of urgent adaptation of the organism to the measured physical load were investigated. The level of urinary excretion of free, bound cortisol, and 17-ketosteroids was analyzed by means of chemiluminescence immunoassay on micro particles using the ARCHITECT i optical system (USA), as well as by the immunoenzymatic colorimetric method using the Urinary Free Cortisol ELISA laboratory unit (EIA-2989). As a functional test, the bicycle ergometric load of moderate power at the rate of 1.5 W per 1 kg of body weight was applied. Having compared the obtained results with the indicators of children that are not involved in sports, it was concluded that the age of 14 and 15 years refers to the period when the reserve of glucocorticoids is formed, thereby increasing the resistance of the bodies of male athletes to physical activity. This is observed with an increase in anabolic processes during the recovery period and with an increase in the role of androgens in switching the body from muscle activity to recovery. The data obtained can serve as a scientific basis for the normalization of the intensity of muscular loads and, taking into account the hormonal status of children, prevention of endocrine dysfunctions in athletes at a young age.
