Sunday, March 6, 2016

Moving for Money

Would you be willing to run around the block each morning in exchange for a free cappuccino or a free ride on the metro? Rewarding people with money increases motivation to exercise, finds a recently published study in Annals of Internal Medicine. During a 13-week intervention, researchers at the University of Pennsylvania managed to motivate their employees to take no less than 7000 steps a day!

Figure 1. Illustration by Iván López Núñez (for Homo Sociabilis)

Two-hundred and eighty-one overweight and obese employees participated in the intervention that rewarded them financially if they completed a daily goal of 7000 steps. Not all participants were rewarded equally, however. They were randomly allocated to different groups, and the financial incentive they received for exercising depended on the group they belonged to. There were four groups, including a control group that did not receive financial rewards. The three groups who did receive a reward were:

1) Gain incentive group: $1.40 given each day the goal was achieved
2) Lottery incentive group: daily eligibility to win a reward worth $1.40
3) Loss incentive group: $1.40 removed daily from an amount of $42 that participants had to allocate upfront monthly for the duration of the intervention

The study showed that those in the loss-incentive group more often achieved their goal than those in the other groups. More specifically, they managed to reach their goal of walking 7000 steps 45% of the days. In the control condition this was 30%, in the gain-incentive group 35%, and in the lottery-incentive group 36%.

This result supports previous research showing that people are more prone to avoid punishment than to seek out rewards, as losses hurt more than gains (Kahneman & Tversky, 1984). An app called “PACT app smartly makes use of this tendency by forming pacts with its users that will reward and punish them financially according to whether they achieve their health goals or not. PACT’s users can commit to three different pacts aimed at three different behaviors: eating more vegetables, working out more, or logging one’s daily food intake. You gain money if you complete the amount of activities you have committed to, and you lose money if you don’t. Activities are monitored using GPS and photos. When asked how PACT motivates him, one user replied: “Well, certainly the fact that if I do not do exercise I get charged!” (Blog PACT app, 2015).

Figure 2. Example of a veggie pact on the PACT app (taken from the marketing images provided by PACT app)

Who exactly gains from these interventions? PACT’s slogan is: “Earn cash for living healthy, paid by members who don’t.” Is it safe to assume that those who earn cash are those physically fit, gaining from those who are physically challenged? Take for instance a comparable exercise-for-money-incentive that was temporarily implemented by Mexico City’s government in order to combat the weight problems of its citizens (Mexico is one of the most obese countries worldwide). Motion-sensitive machines were installed in 21 metro stations that temporarily allowed travelers to perform squats in exchange of a free metro ticket. The best video of this intervention is actually from a similar campaign that was carried out in Moscow to raise awareness of physical exercise and the 2014 Sochi Winter Olympics.

Let’s be honest here, although the video shows a wide range of body types lining up to get a free ticket, it is most likely that those who are physically fit will make use of the system. A morbidly obese person will have trouble performing a squat, and will most definitely not want to try it out in front of curious eyes.

Moreover, whereas in Moscow you needed to perform 30 squats to obtain a free metro ticket, in Mexico a mere ten squats sufficed! Although the exact amount of calories burned per squat is dependent on many factors (i.e. height, weight, intensity of movement), an estimated calculation can be made using the following formula: weight (in pounds) x 0.096 = amount of calories burned per minute of performing squats. This means that a person weighing 70 kg, more or less 140 pounds, would burn 13.4 calories per minute of performing squats. Ten squats will take you no more than 30 seconds (you can try it yourself if you don’t believe it). That’s less than 10 calories burned in exchange for a metro ticket. Well, that’s not going to cure obesity…

Different groups that are likely to be targeted by these incentives are those with lower socio-economic statuses. Research has shown that people with yearly incomes under $45,000 are more willing to exercise in exchange for monetary rewards than those with higher incomes. The study found that whereas high-income participants were more willing to exercise in order to avoid financial losses compared to gaining money, the willingness to exercise of low-income participants was not influenced by gain or loss frames.

Thus, people from lower incomes can be motivated to exercise with more varying interventions. Since obesity levels are higher among those who are poor than those who are rich (Ball & Crawford, 2006), this opens up possibilities to target motivation to exercise in these vulnerable groups. Using both monetary rewards as financial losses in policies and health interventions, such as the PACT app does, could help increase motivation to maintain a healthy exercise routine or diet balance. 


Ball, K., & Crawford, D. (2006). Socio-economic factors in obesity: a case of slim chance in a fat world? Asia Pacific Journal of Clinical Nutrition, 15, 15-20.
Hsu, A. S., & Vlaev, I. (2014). Monetary cost for time spent in everyday physical activities. Social Science & Medicine, 108, 74-80.
Kahneman & Tversky (1984). Choices values and Frames. American Psychologist, 39, 341-350.
Patel, M. S., Asch, D. A., Roy Rosin, M. B. A., Small, D. S., Bellamy, S. L., Heuer, J., ... & Wesby, L. (2016). Framing Financial Incentives to Increase Physical Activity Among Overweight and Obese Adults. Annals of Internal Medicine, 164, 385-394.

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