The role of self-efficacy in the change and maintenance of physical activity

Background. There is evidence to suggest that self-efficacy is an important determinant of physical activity, but it may be more effective at increasing physical activity in some adult populations than others. Existing research has also highlighted that different behaviour change techniques (BCTs) may be required for initiating and maintaining self-efficacy and physical activity changes. The objectives of the present research are: 1) to identify which specific BCTs are included in the most effective interventions for initiating and maintaining changes in self-efficacy and physical activity in adults, 2) to compare the contribution of specific BCTs in initiating and maintaining physical activity changes across different adult populations, 3) to compare the contribution of clusters of BCTs in initiating and maintaining physical activity changes, 4) to assess whether changes in self-efficacy are associated with changes in physical activity behaviour, and 5) to investigate whether the relationship between self-efficacy and physical activity is moderated by outcome expectancies.Methods. A systematic review, with meta-analysis, will be conducted to identify all randomised controlled trials aimed at changing self-efficacy for physical activity of adults.Findings. Intervention content will be coded using the BCT Taxonomy (v1) (Michie et al., 2013). For the meta-analysis, effect sizes for self-efficacy and physical activity will be calculated. Moderator analyses will assess the effectiveness of BCTs across different adult populations, and for initiation compared with maintenance. Discussion. It is expected that this review can develop understanding on which specific intervention components are likely to be effective at initiating and maintaining physical activity changes.