Longitudinal study of open goals in physical activity promotion: protocol for 'Open to Move'.

Open goals (eg, 'see how many steps you can reach today') have developed as a promising strategy for increasing physical activity and producing beneficial psychological outcomes such as autonomous motivation, enjoyment and confidence. However, it is not yet clear what the long-term outcomes of open goals are, what factors moderate their use or whether/how individuals transition away from open goals. Therefore, in this study ('Open to Move'), we aim to understand the mechanisms that explain why, when and for whom open goals are beneficial in promoting and maintaining physical activity. 'Open to Move' is a 12-month, exploratory, mixed-methods longitudinal study involving healthy adults aged 18-69 in Australia. Participants will receive a walking programme based on open goals via a mobile app and website, which will also provide feedback on their step counts and fortnightly one-to-one meetings online for the first 6 months. The outcomes will be measured using self-report surveys, interviews, recorded step counts on a mobile phone and process evaluation. The study is ongoing, and 81 participants have commenced thus far, with a target of 210 participants. We expect to conclude recruitment by August 2025 and anticipate that data collection will be completed by August 2026. This study will develop an understanding of the long-term outcomes of open goals, moderating factors and transitions to other goal types-providing important insights for developing a programme theory that can inform full-scale testing and implementation of open goals within physical activity interventions in future.