Even among people who had just joined a gym and expected to visit regularly, getting paid to exercise did little to make their commitment stick, according to a new study from Case Western Reserve University.

Mariana Carrera

Mariana Carrera

The rewards also had no lasting effect: Gym visits stabilized after the modest incentives ended.

Despite timing incentives to when people were already more motivated to exercise, the approach proved ineffective in initiating a healthy behavior that continues to elude most Americans: Only 21 percent get a recommended amount of weekly exercise, according to the Centers for Disease Control.

In the study, new gym members intended to visit three times per week but ended up averaging one weekly visit by the end of the six-week study.

Nearly 95 percent said they expected to visit the gym more than once per week. But by the end of the third month, only about a third had.

The experiment

For visiting the gym nine total times during the study (an average of 1.5 times per week), participants were promised one of three modest rewards: a $30 Amazon gift card; a prize item, such as a blender, of equivalent value; or a $60 Amazon gift card. A control group received a $30 Amazon gift card regardless of how often they visited. (The value of incentives was based on what gyms were likely to offer.)

After the first week, 14 percent did not visit the gym again.

Incentivized participants showed a slight increase in gym visits in the sixth week—their last chance to make enough visits to earn their prize. But overall, those given incentives made only 0.14 more visits per week than those promised no reward at all.

“Focusing on people when they’re ready to make a change may be misguided,” said Carrera. “Maybe the internal motivation that gets a person to start a gym membership is unrelated to what drives them to earn financial incentives. What’s clear was there was no complementarity in lumping these two motivations together.”

The group that was promised the $60 gift card also did not visit the gym more often than those given the $30 gift card or prize.

Researchers thought that selecting the prize item at the outset might create a sense of ownership and prove to be a more powerful motivator, because failing to hit the target visit rate might feel like a loss. However, while the item induced slightly more visits, the difference was insignificant.

The results appear in a National Bureau of Economic Research working paper.

Co-authors of the paper were Mark Stehr, assistant director of the School of Economics and an associate professor at Drexel University; Heather Royer, an assistant professor of economics at the University of California at Santa Barbara; and Justin Sydnor, an associate professor of risk and insurance at the University of Wisconsin-Madison.


For more information, please contact Daniel Robison as daniel.robison@case.edu


This article was originally published July 31, 2017.

  • Nicole

    In social psychology, this phenomenon is called a “justification of effort.” The participants gained a love of money and rewards, but not a love for going to the gym.

  • thisguy

    The title is a bit misleading. If the rewards failed to motivate, then it would seem they were not actually incentives. It may be better to say “Modest rewards do little to spur gym-going.” (Though a much worse headline) I can’t say the results surprise me given the “modest rewards.” It would be interesting to see at what point the value of rewards begin changing behavior.

    • Leslie Clarke

      I agree with your observation. I would think there is a tipping point at which the money is in fact an “incentive”, but seems to me it would be pretty high and different for different people.
      I remember one of the most successful rewards at 121 for me was reaching 200 miles on whatever equipment you chose and winning a t-shirt that said 200 miles. I busted my butt to get that shirt (still have it!). We had to track our mileage on a sheet as well. There was something about the little gains every day and seeing the progress on paper that kept me going; money would not have done the same thing, it felt like I earned it..