The Effect of Eight-Week Endurance and High-Intensity Interval Training on Leptin, Cortisol and Testosterone Levels in Obese Adolescent Boys

Introduction: Given the critical role of obesity in chronic disease development, establishing effective exercise protocols is essential for managing obesity and regulating energy balance.
Objective: This study aims to investigate the effects of high-intensity endurance and interval training on the hormonal profiles of leptin, cortisol, and testosterone in obese male adolescents.
Methods: This study employed a semi-experimental design with practical implications, utilizing a pre-test and post-test framework alongside a control group. Participants were 50 obese male adolescents who were equally divided into the endurance training group (ET-G), the high-intensity interval training group (HIIT-G), and the control group (C-G). Over an eight-week period, participants engaged in either endurance or HIIT exercises. Blood samples were collected during the pre-test phase after a 14-hour fasting period and again in the post-test phase. Data analysis was conducted using ANCOVA.
Results: The results indicated a significant change in leptin levels (F=13.574, P<0.001) and a greater increase in testosterone levels (F=16.947, P<0.001) and in cortisol levels (F=15.649, P<0.001) from pretest to posttest. Follow-up test showed that HIIT-G experienced a significantly greater reduction in leptin and an increase in testosterone and cortisol levels compared to both ET-G and C-G (P<0.05). Additionally, ET-G showed a significantly greater decrease in leptin levels and an increase in testosterone and cortisol levels than C-G (P<0.05).
Conclusion: The significant alterations observed in hormone level after interval training, suggest that the HIIT employed in this research is an effective strategy for enhancing metabolism and reducing body fat percentage in obese young men.