ABSTRACT Introduction: Physical exercise is an important factor in regulating energy balance and body composition. Exercise itself is a kind of body stress. It involves the central nervous system, cardiovascular, respiratory, endocrine, and other systems. Sports have various effects on the hormones in adolescent height development. Objective: This article analyzes the effects of different time and load exercise training on the levels of serum testosterone, free testosterone, and cortisol in young athletes. Methods: The athletes’ blood samples were collected at the quiet time in the morning before each experiment, immediately after exercise, and at three time intervals the next morning. Then blood testosterone (T), free testosterone (FT), and corticosteroids (C) were measured. Results: One-time and one-day high-volume training can cause a decrease in serum testosterone and free testosterone levels and an increase in cortisol hormones in young athletes. The testosterone level of young athletes rises immediately after exercise. Conclusion: Hormonal changes after physical exercise provide a scientific basis for athlete exercise load prediction and exercise plan formulation. Level of evidence II; Therapeutic studies - investigation of treatment results.