Psychosocial Correlates of Physical Activity in Two Cultural Contexts: Different Pathways?

Background: If the Youth Physical Activity Promotion (YPAP) model adequately explains youth physical activity (PA) in 2 different cultures and with 2 different sets of instruments, it would suggest that the model has broad utility for youth activity promotion. Methods: Two samples from different countries were used: sample 1-USA, 159 students (n = 83 girls) mean age 11.52 +/- 1.40 years; sample-2 Portugal, 203 students (n = 125 girls) mean age 14.99 1.55 years. PA was assessed by accelerometry. The YPAP model was analyzed through structural equation modeling using AMOS (version 17.0). Results: In sample 1, social-support had a direct association on MVPA (beta = .58, P < .001), enjoyment (beta = .70, P < .05), and self-efficacy (beta = -.66, P < .001). Enjoyment significantly predicted MVPA (beta = .60, P < .001) and self-efficacy significantly predicted MVPA (beta = .55, P < .001). In sample 2, social-support had a direct effect on MVPA (beta = .33, P < .05), significantly predicted enjoyment (beta = .43, P < .001), and significantly predicted self-efficacy (beta = .63, P < .001). Self-efficacy was a significant predictor of MVPA (beta = .14, P < .001) but enjoyment was not. Conclusions: Differences were noted in the nature of the relationships and the relative importance. Self-efficacy and social support had significant effects on MVPA in both samples-despite differences in the way that they were measured and operationalized.