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There’s no lack of evidence proving how important exercise is for the body. But does that get you get out of the house and into the gym?
Not if you’re like most Americans, 80% of whom don’t get the recommended amount of aerobic and muscle-building exercise.
“We know that people are not rational,” says Dr. Mitesh Patel, assistant professor of medicine and health care management at the Perelman School of Medicine and the Wharton School at the University of Pennsylvania. “They know exercise is good for them, yet they don’t exercise enough.” But one of the great quirks of human behavior is that we’re irrational in a predictable way, Patel says; people are motivated by losses more than gains and prefer getting rewarded now rather than later.
You can translate that into a surprisingly effective way to get people to move more, according to Patel’s new study published in the Annals of Internal Medicine.
In the trial, Patel and his team assigned 281 overweight and obese people the same goal—to walk 7,000 steps a day. People were tracked for 13 weeks through their smartphones, and only their incentives were different. When they met their goal, some people were merely told that they had done so, while others were entered into a cash lottery. A third group was given $1.40 each day they met the goal. The last group was given $42 at the start of the study and had $1.40 removed for every day they didn’t take enough steps.
People in the first three incentives (get nothing, get entered into a lottery or get about a buck a day) met the goal about 30-35% of the time. But people who stood to lose money met the goal 45% of the time. “We saw dramatically different results when the same amount of money was framed as a loss as opposed to having it framed as a gain,” says Patel.
Past research backs up the idea that financial loss is a powerful incentive for weight loss. Findings like these—that leaving cash on the table could be enough to nudge people to their feet—are potentially useful to companies, which increasingly use corporate wellness programs to encourage their employees to get healthier. “There’s often a presumption that just tracking activity by itself will help you change your behavior,” Patel says. “But in most cases, for the people who really need to benefit the most—those who are overweight or obese—these programs really need to be combined with an effective engagement strategy.”
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Write to Mandy Oaklander at mandy.oaklander@time.com