Can Planning Prompts Change Repeated Behaviors? Evidence from a Randomized Field Experiment on Gym Attendance

Concrete action plans can help people follow through on behaviors they intend to pursue in a broad range of settings. Recent large-scale randomized field experiments have shown that simple and scalable planning interventions -- asking people when and where they plan to act -- are effective for one-time actions, such as obtaining a flu shot, getting a preventative screening, or voting (1). We investigate the effect of a simple scalable planning intervention on a repeated behavior using a large-scale field experiment involving over 800 members of a private gym. Subjects were randomized to either i) a treatment group who selected the days and times when they intended to visit the gym over the next two weeks and received a follow up email containing calendar invites for those days and times or ii) a control group who instead recorded their days of exercise in the prior two weeks. Despite over half of the subjects believing planning to be helpful and despite the exercise plans being strongly correlated with future behavior, we document a tightly estimated null effect of being offered the planning tool on gym attendance. Our confidence intervals exclude positive effects on gym visits over the two-week period of more than 2%.