Maturational timing, physical self-perceptions and physical activity in UK adolescent females: investigation of a mediated effects model

Background: Advanced (early) biological maturation may be a risk factor for inactivity among adolescent girls. Aim: To test the mediational effects of body attractiveness and physical self-worth on the relationship between biological maturity and accelerometer assessed moderate-to-vigorous physical activity (MVPA) in a large multi-ethnic sample of girls from the Midlands area in the UK (11–14 years). Subjects and methods: Biological maturity (predicting age at peak height velocity (APHV)); self-perceptions of body attractiveness, physical self-worth, and minutes spent in MVPA were assessed in 1062 females aged 11–14 years. Results: Structural equation modelling using maximum likelihood estimation and boot- strapping procedures supported the hypothesised model. Later maturation predicted higher perceptions of body attractiveness (β = 0.25, p