Biological Maturation and Physical Activity in South Korean Adolescent Girls.

INTRODUCTION/PURPOSE: To examine whether body fatness (i.e., body mass index and percent body fat) and psychosocial correlates of physical activity (PA) mediate the relationships between pubertal status and PA and sedentary behavior (SB) among South Korean adolescent girls.

METHODS: Pubertal status, body fatness, sport competence, perceived barriers to PA, self-efficacy, parental support for PA, self-reported and step-determined PA, and self-reported SB were assessed among 236 South Korean adolescent girls (mean age = 13.56 ± 1.2 yr).

RESULTS: A direct association was identified between pubertal status and PA in all models; more advanced pubertal status predicted lower PA among South Korean adolescents (b = -0.51 to -0.57; P < 0.001). Indirect effects on the pubertal status-PA relationship were also found: body fatness, perceived barriers to PA, and self-efficacy mediated the relationship between pubertal status and PA. Parental support for PA did not moderate the relationship between maturation and PA. SB was not associated with pubertal status.

CONCLUSIONS: This study found mediated effects of body fatness, and psychosocial correlates (i.e., perceived barriers to PA, self-efficacy) on the relationship between maturity and PA among South Korean adolescent girls. Efforts to promote PA among South Korean adolescent girls should focus on reducing perceived barriers to PA, and increasing self-efficacy by providing more opportunities to have positive, and enjoyable experiences in PA among early-maturing girls.