Much has been made of the “runner’s high,” the euphoria attributed to pleasure-inducing neurotransmitters like dopamine and endorphins (the brain’s endogenous opiates) being released in the brain during exercise. But the question is, if exercise causes the same brain changes as do other rewarding activities like, say, taking drugs, why, then, don’t exercisers crave their workouts the way addicts crave drugs?
Addicts have no lack of motivation to seek the stuff they crave, but most gym-goers — even the most dedicated — have the opposite problem. They have to force themselves to work out despite the strong pull of inertia: “The bed feels so warm and comfortable,” “I can’t leave the office,” “I just don’t wanna!”
Now a new study led by Matthew Ruby at the University of British Columbia and published in Health Psychology explores the reasons for this lack of motivation and suggests that there may be easier ways to conquer it.
The fundamental problem with exercise is that people have to predict how good they’ll feel afterward in order to motivate themselves to do it. And people are notoriously bad at predicting how they’ll feel in the future. For example, people tend to remain in petering out romantic relationships longer than they should, overestimating how painful the break-up will be; afterward, they wallow alone at home in their depression, underestimating how beneficial socializing with friends will be for mending their broken heart.
A critical part of the distortion in these “affective forecasts” involves the timing of events. With exercise, the pain comes before the pleasure. The beginning part of a workout is much less enjoyable than the middle or end. (With drugs, of course, the opposite is true: the fun comes first, followed by the hangover or withdrawal.)
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The early unpleasantness of exercise, the study suggests, causes a form of myopia, or short-sightedness, which leads people to focus unduly on the initial pain, rather than the later joy. Researchers found that this occurs with many types of exercise, including aerobics, weight training, yoga, Pilates and spinning. (And with addiction, the early pleasure produces a myopia of its own: a failure to consider the long term consequences).
In one experiment, researchers studied 40 members of a gym, randomly assigning 21 to predict their enjoyment before they took a class and then report on what they’d actually felt afterward. The rest just rated how they felt after their workout. As expected, the people who were asked to predict how good they’d feel before they started significantly underestimated their actual enjoyment.
In another part of the study, 32 campus gym members were asked to design either moderate or challenging workouts for themselves to complete. Before starting, both groups predicted how much they would enjoy the exercise. And, regardless of the intensity of the workout, both predicted far less fun than they actually experienced.
In two additional tests, researchers explored ways of changing these predictions to enhance motivation. In one experiment, a group of 53 gym members were asked either to perform their workout as usual and predict how much they’d like it, or to start with their favorite exercises first and leave their least favorite for last. Those who put their favorites first predicted enjoying their workout more than those who did their usual routines.
A final experiment involved 154 people who volunteered to participate in a study of a spinning class using stationery exercise bikes. The participants read descriptions of the “race day” class and how it would vary in intensity over time. One group was simply asked to predict how much they might enjoy taking the class, while the rest were asked to predict enjoyment at each stage of the “race” before making an overall prediction.
Those asked to spread their attention across the workout anticipated more pleasure than the group asked simply to predict enjoyment overall — likely by shifting their focus away from the painful beginning. This group also expressed greater intention to exercise in the future.
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So how can you use this information to help get yourself to the gym? First of all, start by focusing on the genuine joy that comes later in your exercise routine, rather than the pain of starting. If you ignore or downplay thoughts about starting and concentrate on the finish line, you can increase your motivation to start.
Also, try rearranging your routine so that you start with your favorite exercises first (save those dreaded abdominal crunches for last!), which may help you get focused on pleasure rather than pain.
You could also rehabilitate your entire attitude about exercise and start viewing it as the ideal drug: not only does the pain come before the pleasure, so you don’t get hooked, but you also wind up feeling better rather than worse in the long run.
Either way, finding a routine that you like and reminding yourself that you actually do like it can help, especially when all you want to do is stay in bed.
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Maia Szalavitz is a health writer at TIME.com. Find her on Twitter at @maiasz. You can also continue the discussion on TIME Healthland’s Facebook page and on Twitter at @TIMEHealthland.