Purpose: Increasing self-efficacy is an effective method to increase physical activity. Despite this, the evidence concerning the most effective techniques to increase self-efficacy in physical activity interventions has not been systematically reviewed. The aim of the present research is to systematically gather, and meta-analyse, intervention studies which aimed to increase self-efficacy for physical activity; to estimate the association between intervention techniques used, and change in self-efficacy achieved.
Methods: A systematic database search was conducted for papers reporting lifestyle or recreational physical activity interventions. Published intervention studies explicitly targeting self-efficacy in order to change physical activity behaviour in 'healthy' adults were eligible for inclusion.
Results: The search strategy identified 27 unique physical activity intervention studies, with a total of 5,501 participants. A significant, yet small, relationship between the interventions and changes in self-efficacy was found (mean d=0.16, p<.001). Owing to significant heterogeneity, moderator analyses were conducted, examining the association of changes in self-efficacy with whether or not specific intervention techniques were used. Interventions that included feedback on past or others' performance produced the highest levels of self-efficacy found in this review. Vicarious experience was also associated with higher levels of self-efficacy. Persuasion, graded mastery, and barrier identification were associated with lower levels of self-efficacy.
Conclusions: This meta-analysis forms an evidence base for which psychological techniques are most effective in increasing self-efficacy for physical activity. The results are presented in terms of recommendations for those developing interventions and directions for future research.