Promoting physical activity with open goals: A pilot randomised controlled trial

Open goals are a promising strategy for increasing physical activity and are feasible for inclusion in walking programs. However, longer-term studies comparing open goals to traditional specific goal approaches are needed to inform real-world translation. Therefore, this pilot study compared open goals to specific goals and a control condition in a six-week walking program with four-week follow-up. A mixed-methods randomised controlled trial was conducted with 30 healthy adults (26 female; M_age = 52.07, SD = 10.85) with low-to-moderate physical activity levels. Participants in all conditions received pedometers, exercise diaries, and support sessions; only the open and specific goals groups were given weekly goals. Outcomes included step counts, psychological measures (e.g., enjoyment, self-efficacy, intrinsic motivation, affect, and mental health), and implementation outcomes (acceptability, adherence, retention, fidelity). Interviews explored participants' program experiences. Both open and specific goals increased physical activity post-intervention to a similar extent, although open goals showed the largest within-group increases (M = 2965 steps; d = 1.06) and a steeper decline at follow-up. By follow-up, step counts in all groups were similar to or above baseline, with more positive program experiences reported in the open goals group. Retention was high across groups during the intervention, with reduced fidelity and behavioural spill-over effects observed at follow-up. This study provides further evidence that a walking program incorporating open goals is feasible to deliver and achieves similar physical activity increases to a specific-goal program, while potentially promoting more positive psychological experiences. Findings support the need for a larger-scale randomised controlled trial and provide important design considerations for future research.