Commitment lotteries promote physical activity among overweight adults - A cluster randomized trial

Koen Van Der Swaluw, Mattijs S. Lambooij, Jolanda J.P. Mathijssen, Maarten Schipper, Marcel Zeelenberg, Stef Berkhout, Johan J. Polder, Henriëtte M. Prast

Research output: Contribution to JournalArticleAcademicpeer-review


Background: The World Health Organization has identified physical inactivity as the fourth leading risk factor for global mortality. People often intend to engage in physical activity on a regular basis, but have trouble doing so. To realize their health goals, people can voluntarily accept deadlines with consequences that restrict undesired future behaviors (i.e., commitment devices). Purpose: We examined if lottery-based deadlines that leverage regret aversion would help overweight individuals in attaining their goal of attending their gym twice per week. At each deadline a lottery winner was drawn from all participants. The winners were only eligible for their prize if they attained their gym-attendance goals. Importantly, nonattending lottery winners were informed about their forgone prize. The promise of this counterfactual feedback was designed to evoke anticipated regret and emphasize the deadlines. Methods: Six corporate gyms with a total of 163 overweight participants were randomized to one of three arms. We compared (i) weekly short-term lotteries for 13 weeks; (ii) the same short-term lotteries in combination with an additional long-term lottery after 26 weeks; and (iii) a control arm without lotteries. Results: After 13 weeks, participants in the lottery arms attained their attendance goals more often than participants in the control arm. After 26 weeks, we observe a decline in goal attainment in the short-term lottery arm and the highest goal attainment in the long-term lottery arm. Conclusions: With novel applications, the current research adds to a growing body of research that demonstrates the effectiveness of commitment devices in closing the gap between health goals and behavior.

Original languageEnglish
Pages (from-to)342-351
Number of pages10
JournalAnnals of Behavioral Medicine
Issue number4
Early online date25 Jan 2018
Publication statusPublished - 15 Mar 2018


  • Behavior change
  • Behavioral economics
  • Commitment devices
  • Deadlines
  • Health promotion
  • Physical activity


Dive into the research topics of 'Commitment lotteries promote physical activity among overweight adults - A cluster randomized trial'. Together they form a unique fingerprint.

Cite this