Effect of exercise on hormonal responses in adolescents with obesity and leptin resistance: a randomized trial

This study examined the effects of regular plyometric exercise on growth hormones, appetite hormones, myokines, and adipokines in adolescents with obesity and leptin resistance. Sixty adolescents (male: 11.9 ± 0.8 years; female: 13.0 ± 1.0 years) with body fat ≥ 30% and leptin ≥ 30 ng/mL participated between July 2023 and October 2024 following IRB approval. Participants were randomized by gender into control or exercise groups (n = 15 per gender). The exercise group completed a 12-week program (3 sessions/week, 150 min/week). Twelve participants withdrew (CON, n = 6; PE, n = 6). Thus, 48 participants completed the study and were included in the final per-protocol analysis. Assessments included body composition, muscle fitness (grip strength, isokinetic torque), and blood biomarkers. Significant improvements were observed in height, muscle mass, fat mass, body fat percentage, BMI, and muscle fitness in the exercise group (p < 0.05). GH and IGF-1 increased, with reduced myostatin and elevated follistatin (p < 0.05). Leptin sensitivity improved with increased adiponectin (p < 0.05). TNF-α showed no significant change. Findings suggest that plyometric exercise is an effective non-pharmacological approach to enhance growth, body composition, muscle fitness, and endocrine regulation in adolescents with obesity and leptin resistance.