The intention-behaviour gap in physical activity: a systematic review and meta-analysis of the action control framework

Objective Intention is the proximal antecedent of physical activity in many popular psychological models. Despite the utility of these models, the discrepancy between intention and actual behaviour, known as the intention-behaviour gap, is a central topic of current basic and applied research. The purpose of this meta-analysis was to quantify intention-behaviour profiles and the intention-behaviour gap. Design Systematic review and meta-analysis. Data sources Literature search was conducted in June 2022 and updated in February 2023 in five databases. Eligibility criteria for selecting studies Eligible studies included a measure of physical activity, an assessment of physical activity intention and the employment of the intention-behaviour relationship into profile quadrants. Only papers published in the English language and in peer-reviewed journals were considered. Screening was assisted by the artificial intelligence tool ASReview. Results Twenty-five independent samples were selected from 22 articles including a total of N=29 600. Random-effects meta-analysis revealed that 26.0% of all participants were non-intenders not exceeding their intentions, 4.2% were non-intenders who exceeded their intentions, 33.0% were unsuccessful intenders and 38.7% were successful intenders. Based on the proportion of unsuccessful intenders to all intenders, the overall intention-behaviour gap was 47.6%. Conclusion The findings underscore that intention is a necessary, yet insufficient antecedent of physical activity for many. Successful translation of a positive intention into behaviour is nearly at chance. Incorporating mechanisms to overcome the intention-behaviour gap are recommended for clinical practice.