AbstractPhysical activity levels decrease during adolescence. Exposure to a variety of physical activities (e.g., concept of sampling within the developmental model of sport participation) has been suggested to foster physical activity, but little is known about the psychosocial mechanisms underlying the variety support-physical activity relationship. This study examined the relationship between different forms of variety support (number of activities, locations, and social contacts) and physical activity behaviour in adolescence. Perceptions of variety and basic psychological needs (competence, autonomy, relatedness) were tested as mediators. Participants (N = 369; Mage = 15 years; 59% female) completed a 36-item checklist representing their participation in physical activity, where they participated in those activities, and with whom they participated with, at 3 time points over a year (Time 1, 2 and 3). Perceptions of variety, competence, autonomy, and relatedness were measured 20 months after Time 1 (Time 4), and physical activity behaviour was measured 28 months after Time 1 (Time 5). Mediation using structural equation modeling was examined. Results showed that sampling activities (? = .21, p = .010), but not locations (? = .18, p = .052), or various social contacts (? = -.03, p = .772), positively predicted physical activity behaviour over time. Sampling had an indirect positive effect on physical activity behaviour (R2 = .26) through perceptions of variety (? = .12, p = .012), but not through perceptions of competence, autonomy, or relatedness. Theoretical and practical implications are discussed in relation to the developmental model of sport participation and self-determination theory.
Acknowledgments: This research was supported by a Social Sciences and Humanities Research Council of Canada Post-Doctoral Fellowship awarded to Benjamin Sylvester. Isabelle DorÃ© is supported by a Fond de recherche du QuÃ©bec â€“ SantÃ© post-doctoral research fellowship. Catherine Sabiston is supported by the Canada Research Chairs program. The data used in this analysis were drawn from the MATCH project, which was funded by the Social Sciences and Humanities Research Council and Sport Canada through the joint Sport Participation Research Initiative (Nos. 862-2010-0001 and 862-2014-0002) and by the New Brunswick Health Research Foundation (No. 20130729).