Parental and peer influences on physical activity among Scottish adolescents: a longitudinal study.

BACKGROUND This study investigated parental and peer influences on physical activity, examining gender and developmental differences during early-mid adolescence. METHODS A 5-year longitudinal study tracking physical activity (measured by PAQ-C) among adolescents (n = 641) from final year of primary (P7) to fourth year of secondary school (S4). Peer support, peer socializing, parental support, and independent play were assessed. Logistic regression predicted physical activity, by year and gender, in relation to social influences. RESULTS Boys reported higher physical activity, peer support, paternal support, and independent play than girls. Among both genders, peer, paternal, and maternal support decreased with age, whereas independent play increased. Time with friends was particularly important. Among high socializers (P7), odds of being active were over 3 times those of low socializers [boys: 3.53 (95% CI 1.77, 7.04), girls: 3.27 (95% CI 1.80, 5.92)]. Baseline physical activity was also a strong predictor among early secondary boys (OR 3.90 95% CI 2.10, 7.24) and girls (OR 4.15, 95% CI 2.00, 8.62). Parental support was less important than peer influences; only same-sex parental support remained significant in multivariables models. CONCLUSIONS Parents and peers have important influences on adolescent physical activity. Significant gender and developmental effects are apparent through early-mid adolescence.