Relationship Between Weight Status and Self-Image Mediated by Pubertal Timing and Athletic Competence: A Cohort Study With Taiwanese Adolescents

BACKGROUND: Self-image reflects overall self-acceptance in developing adolescents. Using a representative cohort of Taiwanese youth, this study aims to explore the relationship between weight status, pubertal timing, athletic competence, and adolescent self-image. METHODS: Data come from the Taiwan Youth Project that comprised a longitudinal cohort of adolescents (N = 2690, 51% males, Mage = 13.3 ± 0.5 years) surveyed annually from seventh grade. Self-image was measured by perceived satisfaction with appearance and physique. Weight status was proxied by self-reported body mass index (BMI; kg/m(2)). Pubertal timing was defined using the Pubertal Developmental Scale, which mainly measured physical changes in puberty. Athletic competence was assessed by experiences with participation in competitive sports and self-perceived talent for sports. Linear regression analysis was applied to test for an association between BMI and self-image. In order to test for mediating roles of pubertal timing and athletic competence, Hayes' PROCESS macro on SPSS was conducted applying 5,000 bootstrap resamples with 95% confidence intervals of the indirect effect. RESULTS: BMI was inversely associated with self-image in both males (β = −0.074, [−0.095, −0.053]) and females (β = −0.095, [−0.122, −0.069]). The boot-strapped 95% confidence intervals indicated statistically significant mediating effects of pubertal timing (β = −0.008, [−0.015, −0.001]) and athletic competence (β = −0.006, [−0.011, −0.002]) in the link between BMI and self–image in females, whilst only athletic competence mediated this association (β = −0.006, [−0.009, −0.002]) in males. Moreover, BMI at baseline were also associated with long-term self-image in males (β = −0.037, [−0.057, −0.017]) and females (β = 0.132, [0.073, 0.190]). CONCLUSIONS: Understanding the mediating factors may help enhance adolescents' self-image by providing guidance on healthy weight and physical activity behaviors according to different stages of pubertal progression.