Our exercise habits may influence our sense of purpose in life, and our sense of purpose may affect how much we exercise, according to an interesting new study of the reciprocal effects of feeling your life has meaning and being in motion often. The study, which involved more than 18,000 middle-aged and older men and women, found that those with the most stalwart sense of purpose at the start were the most likely to become active over time, and vice versa.

The findings underscore how braided the relationship between physical activity and psychological well-being can be, and how the effects often run both ways.

Science already offers plenty of evidence that being active bolsters our mental, as well as physical, health. Study after study shows that men and women who exercise are less likely than the sedentary to develop depression or anxiety. Additional research indicates that the reverse can be true, and people who feel depressed or anxious tend not to work out.

But most of these studies examined connections between exercise and negative moods. Fewer have delved into positive emotions and their links with physical activity, and fewer still have looked at the role of a strong sense of purpose and how it might influence whether we move, and the other way around.

This omission puzzled Ayse Yemiscigil, a postdoctoral research fellow with the Human Flourishing Program at Harvard University, who studies well-being. “A sense of purpose is the feeling that you get from having goals and plans that give direction and meaning to life,” she says. “It is about being engaged with life in productive ways.”

This definition of purpose struck her as overlapping in resonant ways with many people’s motivations for exercise, she says.

“Active people often talk about how exercise gives structure and meaning to their lives,” she says. “It provides goals and achievements.”

In that case, she thought, physical activity plausibly could contribute to a sense of purpose and, likewise, a sense of purpose might influence how likely we are to exercise.

But there was scant evidence to support those ideas. So, for the new study, which was published in April in the Journal of Behavioral Medicine, she and her colleague Ivo Vlaev, a professor of behavioral science at the University of Warwick in England, set out to find links, if any, between moving and meaning.

They began by turning to the large and ongoing Health and Retirement Study, which gathers longitudinal data about the lives, attitudes and activities of thousands of American adults aged 50 or older. It asks them at the start about their physical health, background, daily activities and mental health, including if they agree with statements like, “I have a sense of direction and purpose in life,” or “My daily activities often seem trivial and unimportant.” The study’s researchers then checked back after a few years to repeat the queries.

Then, Yemiscigil and Vlaev drew records for 14,159 of the participants. To enlarge and enrich their sample, they also gathered comparable data for another 4,041 men and women enrolled in a different study that asked similar questions about people’s physical activities and sense of purpose.

Finally, they collated and compared the results, determining, first, how much and how vigorously people moved, and also how strong their sense of purpose seemed to be. The researchers then assessed how those disparate aspects of people’s lives seemed to be related over the years, and they found clear intersections. People who started off with active lives generally showed an increasing sense of purpose over the years, and those whose sense of purpose was sturdier in the beginning were the most physically active years later.

The associations were hardly outsize. Having a firm sense of purpose at one point in people’s lives was linked, later, with the equivalent of taking an extra weekly walk or two. But the associations were consistent and remained statistically significant, even when the researchers controlled for people’s weight, income, education, overall mental health and other factors.

“It was especially interesting to see these effects in older people,” Yemiscigil says, “since many older people report a decreasing sense of purpose in their lives, and they also typically have low rates of engagement in physical activity.”

This study was based, though, on people’s subjective estimates of their exercise and purposefulness, which could be unreliable. The findings are also associational, meaning they show links between having a sense of purpose at one point in your life and being active later, or vice versa, so they do not prove one causes the other.

But Yemiscigil believes the associations are solid and rational.

“People often report more self- efficacy” after they take up exercise, she says, which might prompt them to feel capable of setting new goals and developing a new or augmented purpose in life. And from the other side, “when you have goals and a sense of purpose, you probably want to be healthy and live long enough to fulfill them.”

So, cue exercise, she says.

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