Constructs of physical activity behaviour in children: The usefulness of Social Cognitive Theory

Objectives: The purpose of this study was to investigate the relationships among several Social Cognitive Theory (Bandura, 2004) constructs (e.g., self-efficacy) and children's physical activity behaviours. Design: Children from six elementary schools (N= 479) in grades 4th to 6th from five different school districts in the Southwestern USA participated in this study by completing a sociocognitive instrument as well as wearing a pedometer for five school days. Methods: Previously validated scales were combined and administered to all children in order to examine the relationships among five constructs (self-efficacy, outcome expectations, social support, barriers, and goals) and physical activity participation was measured via pedometer. Data analyses included a two-step approach with confirmatory factor analysis followed by structural equation modelling. Results: The confirmatory factor analyses indicated an adequate fit of the specified model. The structural model fit statistics also suggested that the data fit the specified model: χ ² (8, N=476)=24.44, p=0.00, χ ²/df=3.06, GFI=0.98, AGFI=0.96, CFI=0.93, RMSEA=0.07. The model explained 15% of the variance in social support, 11% of the variance in goals, 11% of the variance in barriers, 9% of the variance in outcome expectations, and 2% of the variance in physical activity. Self-efficacy was a strong predictor of total social support, total number of barriers, and outcome expectations. Conclusions: This study supports the use of Social Cognitive Theory in understanding the constructs of physical activity behaviour in children, however, very little variance in behaviours was explained. There is a need to also investigate environmental influences on children's decisions to be physically active.