There is convincing evidence that targeting self-efficacy is an effective means of increasing physical activity. However, evidence concerning which are the most effective techniques for changing self-efficacy and thereby physical activity is lacking. The present review aims to estimate the association between specific intervention techniques used in physical activity interventions and change obtained in both self-efficacy and physical activity behaviour. A systematic search yielded 27 physical activity intervention studies for "healthy" adults that reported self-efficacy and physical activity data. A small, yet significant (P less than 0.01) effect of the interventions was found on change in self-efficacy and physical activity (d = 0.16 and 0.21, respectively). When a technique was associated with a change in effect sizes for self-efficacy, it also tended to be associated with a change (r[subscript s] = 0.690, P less than 0.001) in effect size for physical activity. Moderator analyses found that "action planning", "provide instruction" and "reinforcing effort towards behaviour" were associated with significantly higher levels of both self-efficacy and physical activity. "Relapse prevention" and "setting graded tasks" were associated with significantly lower self-efficacy and physical activity levels. This meta-analysis provides evidence for which psychological techniques are most effective for changing self-efficacy and physical activity.