Objective: To examine the relationship between perceived family support and other selected correlates of physical activity (PA) with changes in PA over time.
Methods: A total of 421 girls in South Carolina completed questionnaires at 8th, 9th and 12th grades (1998-2003). Family support for PA, PA self-efficacy, perceived behavioral control, attitudes, availability of equipment, and PA were measured.
Results: Growth curve analysis showed that family support, perceived behavioral control, and self-efficacy were independently related to age-related changes in PA as reflected by total METs. Girls who reported lower family support at the 8th grade measure had more rapid declines in PA, and a unit change in family support was related to approximately 1/3 of a standard deviation change in total METs.
Conclusions: Maintenance of support from family members may reduce the decline in PA independent of girls' self-efficacy and perceived behavioral control.