Hormonal adaptations to moderate-intensity endurance training in sedentary obese men

Introduction: Exercise and physical activity improve obesity and its complications via affecting on hormones regulating energy homeostasis and metabolism. This study examined the influence of moderate-intensity endurance training on serum levels of leptin, cortisol, testosterone, growth hormone and insulin Resistance Index (HOMA-IR) in sedentary obese men.Materials and Methods: 20 sedentary obese men (BMI≥30) in two experimental and control groups participated in 16 weeks of moderate- intensity endurance training (60-70% of reserve heart rate), three days per week. Serum levels of leptin, cortisol, testosterone, growth hormone and insulin, and anthropometric indices were measured before and after the last training session.Results: Although 16 weeks of moderate- intensity endurance training significantly decreased leptin level (P=0.003) and increased cortisol (P=0.009) and growth hormone (P=0.040) levels, but no significant changes was observed in testosterone and insulin concentrations, and insulin resistance index in training group (P>0.05). Pearson correlation did not mentioned significant correlations between the primary level of leptin and primary values of anthropometric indices and HOMA-IR (P>0.05). However following the intervention, there were significant correlations between changes in leptin concentrations and changes in weight, BMI, waist circumference and WHR (P<0.05).Conclusion: Moderate- intensity endurance training improves body composition and changes leptin, cortisol and growth hormone concentration; and therefore ameliorates metabolic hormonal profile in obese men. However, these changes may not be in the line with changes in insulin and testosterone