Trans-Contextual Model Predicting Change in Out-of-School Physical Activity: A One-Year Longitudinal Study

The aim of the current study was to test the long-term predictive validity of the trans-contextual model in accounting for variance in adolescents' out-of-school physical activity measured by self-report and accelerometer based-devices over a one-year period. Secondary school students (N = 265) aged 11 to 15 years completed a three-wave survey on two occasions in time, spanning a one-year interval, measuring perceived autonomy support in physical education (PE), peer and parent autonomy support in leisure-time, autonomous and controlled motivation in PE and leisure-time, attitude, subjective norms, perceived behavioural control, intention, and out-of-school physical activity both by self-report and accelerometer-based devices. A variance-based structural equation model using residualized change scores revealed that perceived autonomy support from PE teachers predicted autonomous motivation in PE, and autonomous motivation in PE predicted autonomous motivation in leisure-time. In addition, peer and parent autonomy support predicted autonomous motivation in leisure-time. Autonomous motivation in leisure-time indirectly predicted physical activity intention mediated by attitude and perceived behavioural control. Intention predicted self-reported physical activity participation, although the effect was in the opposite direction to our prediction, but not physical activity measured by accelerometer-based devices. Results support some tenets of the trans-contextual model over a one-year time period, particularly the determinants of physical activity intentions. The introduction of COVID-19 restrictions may explain the negative relationship between intention and self-reported physical activity. Further longitudinal studies are needed to verify the results of the current study.