Commitment Lotteries Promote Physical Activity Among Overweight Adults-A Cluster Randomized Trial

Area of Science:

• Behavioral Economics
• Public Health
• Exercise Science

Background:

• Physical inactivity is a major global health risk, contributing significantly to mortality.
• Many individuals struggle to consistently engage in desired physical activity.
• Commitment devices, which impose future consequences for undesired behavior, can help achieve health goals.

Purpose of the Study:

• To investigate the efficacy of lottery-based deadlines, utilizing regret aversion, for overweight individuals aiming for twice-weekly gym attendance.
• To assess if counterfactual feedback to non-winners enhances motivation through anticipated regret.

Main Methods:

• A randomized controlled trial involving 163 overweight participants across six corporate gyms.
• Three arms were compared: weekly short-term lotteries, combined short-term and long-term lotteries, and a control group.
• Intervention duration was 13 weeks for short-term lotteries and 26 weeks for the long-term component.

Main Results:

• Participants in lottery arms showed higher goal attainment than the control group after 13 weeks.
• After 26 weeks, short-term lottery adherence declined, while the long-term lottery group exhibited the highest goal attainment.
• Lottery winners were informed of their prize eligibility contingent on meeting gym attendance goals.

Conclusions:

• Lottery-based commitment devices are effective in promoting physical activity and bridging the intention-behavior gap.
• Long-term lottery designs appear more effective for sustained adherence to health goals compared to short-term lotteries alone.
• This research highlights novel applications of commitment devices in health behavior interventions.