Background: The transition from childhood to adulthood is associated with many physiological changes that result from hormonal changes. Despite this, it has been reported that hormonal response to exercise can be age-dependent.the purpose of this study was to investigate growth hormone, insulin, testosterone, and cortisol response to acute intensive exercise in children, adolescents, and youth male athletes. Materials and Methods: Twenty-nine eligible football players volunteered to participate in the study. Participants assigned to three groups: children (age = 10.88 ± 0.92, n=9), adolescents (age = 14.40 ± 1.17, n=10), and youth (age = 17.70 ± 0.82, n=10). The Bruce Protocol Stress Test was performed as an acute intensive exercise on treadmill. Plasma hormones were measured before and after the exercise. Results: The acute intensive exercise leads to a significant increase in circulating levels of testosterone (p = 0.02) and Cortisol in children (p = 0.001). In the adolescent group, only a significant increase in GH (p = 0.001) was observed. In the youth group a significant increase in GH (p=0.05) and testosterone (p=0.001) was observed. However, insulin levels did not change significantly after intensive exercise in all groups. Results showed that there were no significant differences between hormonal changes within the three groups. Conclusion: The results showed that the basal levels of some hormones and their changes after exercise were different. However, the pattern of hormonal changes after acute intensive exercise was similar in children, adolescents, and young athlete boys. پرونده مقاله