This study assessed the effectiveness of a sports nutrition intervention designed to improve body composition in 25 high-school male athletes over a 12-week period. Employing a mixed-methods approach within a quasi-experimental one-group pretest-posttest design, the intervention integrated nutrition education with the provision of food. Quantitative results revealed significant reductions in body fat percentage and fat mass, and an increase in fat-free mass. Qualitative insights highlighted the untapped nutritional potential of adolescents and emphasized the importance of accessibility and simplicity in driving compliance. The findings suggest that targeted nutritional interventions can positively impact adolescent athletes' body composition. The study underscores the need for practical approaches to nutritional guidance that resonate with youth, offering valuable insights for sports professionals, coaches, and parents.