The impact of exercise self-efficacy, self-esteem and physical activity on body fat percentage changes in adolescents during fat loss interventions.

The prevalence of obesity among adolescents poses significant health threats. This study examines the predictive influence of self-efficacy (ESE), self-esteem (SE), and moderate-to-vigorous physical activity (MVPA) on the effectiveness of interventions aimed at reducing body fat percentage (BFP) among adolescents. A total of 100 adolescents were randomly assigned to the intervention group (IG) or the control group (CG). Baseline assessments measuring body composition, psychological indicators, and physical activity levels were conducted prior to the intervention. Intervention effects and group differences were evaluated using t-tests. Hierarchical regression models were constructed, using post-intervention BFP as the dependent variable (controlling for baseline). Following a 12-week structured intervention that included aerobic exercise, resistance training, and caloric restriction, The IG showed a reduction in BFP of 2.75% ± 1.90%, an increase in ESE of 12.14 ± 6.13 points, and an increase in SE of 8.58 ± 4.40 points. Hierarchical regression analysis in the IG revealed that increases in SE and MVPA were both significantly associated with negative changes in BFP (SE: β = -0.159, P < 0.001; MVPA: β = -0.079, P = 0.046). In the CG, no significant associations were found between changes in psychological factors and BFP after controlling for baseline levels. These findings underscore the pivotal role of psychological determinants in the effectiveness of weight loss interventions and suggest the need for an integrated approach that considers both physical activity and mental health to effectively manage obesity among adolescents.