Why We Should Think of Exercise as Its Own Reward
Exercise can be as tempting as food. It’s just less convenient for many of us.
Posted March 4, 2019
Many of us think of exercise as something we need to bribe ourselves to do. But maybe we’ve got it all wrong. Enjoyable exercise can be intrinsically rewarding, just like tasty food is, according to a study published in the February issue of Physiology & Behavior.
From rats on a running wheel…
In rodents, scientists had already shown that exercise can be powerfully rewarding, says study coauthor Hans-Peter Kubis , a senior lecturer in sport and exercise science at Bangor University in Wales. Rats and mice will not only use running wheels without prompting. They’ll actually learn to work to gain access to the running wheels, and they’re vocal about their eagerness to get moving.
“One study showed that rats, which had been given restricted daily access to wheel running, emitted 50 kHz calls in anticipation of and during running,” Kubis says. “These calls are known to signal a positive affective state usually seen in the context of food rewards and social play.”
But do humans also view exercise as its own reward? That’s what Kubis and his colleagues set out to learn.
…To humans on a treadmill
Their study included 70 young, moderately active men and women. Over three sessions on a treadmill, the participants were asked to adjust the treadmill speed until they found the pace they liked best. Later, they were asked to recall these pleasant exercise sessions when answering a series of questions.
The questions were carefully constructed to look at delay discounting, the devaluation of rewards over time. Researchers often study delay discounting to find out how the nature of a reward affects people’s decision-making. As a general rule, people tend to prefer larger and more immediate rewards over smaller and delayed rewards.
The decision gets more complicated when they’re asked to choose between a smaller reward that’s available sooner versus a larger reward that’s available later. For some rewards, such as food, a delay in receiving it leads to a steep decline in its perceived value. People tend to choose a tasty meal now rather than several meals six months from now. In contrast, the perceived value of money is discounted less steeply. People are more willing to wait for a larger monetary payoff down the road.
In the study’s delay-discounting task, participants were asked to make hypothetical choices about three potential rewards — pleasant exercise, tasty food, and money. The researchers wanted to know at what point they would stop holding out for a larger, later reward and accept a smaller, sooner one.
As it turned out, the way people regarded pleasant exercise was quite similar to the way they viewed tasty food. Exercise was rewarding, but the value declined steeply if they had to wait for it.
Take a walk or grab a snack?
Viewed from this perspective, it’s easy to see why choosing to eat might seem more enticing than choosing to exercise. “People tend to decide in favor of the item that has the highest value at a particular moment in time,” says Kubis.
When you’re at home or work, a quick bite to eat is often as close as the nearest fridge or vending machine. But you may think of exercise as something that has to wait until you can get to your health club or yoga class. “The delay in receiving the exercise reward devalues it dramatically,” Kubis says. In that choice situation, food often wins out.
On a societal level, the decision-making balance could be shifted by providing more opportunities for exercising throughout the day, and fewer for eating junk food. “Making exercise accessible at work in an organized manner, and integrating further rewards like social play into it, would increase people’s physical activity and health,” says Kubis. “Big employers should be supported to achieve this while reducing the availability of snacks in workspaces.”
Redefining exercise as a treat
On a personal level, these are some things you can do to help maximize the reward potential of exercise:
- Look for quick, enjoyable ways to exercise without delay. You can still go for a gym workout, exercise class, or three-mile walk later on. But don’t put off being active for too long. Weave quick bursts of pleasant exercise throughout your day: for example, by taking a stroll around the block or doing a brief workout with your favorite exercise app.
- Make unhealthy eating choices less accessible than exercise. Don’t stock your home fridge and pantry with foods and beverages you’ll regret consuming. And take the candy bars out of your desk drawer.
- Remind yourself of your other motivators to move. For example, do you want to get stronger, improve your health, or better manage your weight? In Kubis’ study, the reward value of exercise declined more slowly in people with higher exercise motivation, compared to those with low exercise motivation.
Not every exercise session needs to fit the immediate-gratification mold, just as not every food you eat needs to be a tantalizing appetizer or dessert. Some workouts are heavier on the work and lighter on the fun. And some forms of exercise require you to wait for a specific time and place to indulge.
But by liberally sprinkling your day with pleasant, no-wait physical activities, you’ll remind yourself that exercise doesn’t have to be a chore. It can be a treat, and that's something to look forward to.
Albelwi, T. A., Rogers, R. D., & Kubis, H. (2019). Exercise as a reward: Self-paced exercise perception and delay discounting in comparison with food and money. Physiology & Behavior, 199, 333-342. doi:10.1016/j.physbeh.2018.12.004