The Joy of Movement: How Exercise Helps Us Find Happiness, Hope, Connection, and Courage

by Kelly McGonigal

Around the world, people who are physically active are happier and more satisfied with their lives. This is true whether their preferred activity is walking, running, swimming, dancing, biking, playing sports, lifting weights, or practicing yoga. People who are regularly active have a stronger sense of purpose, and they experience more gratitude, love, and hope. They feel more connected to their communities, and are less likely to suffer from loneliness or become depressed.

During physical activity, muscles secrete hormones into your bloodstream that make your brain more resilient to stress. Scientists call them “hope molecules.”

On a typical day, the Hadza engage in two hours of moderate to vigorous activity, like running, and several more hours of light activity, like walking. There is no difference in activity level between men and women or between young and old.

Contrast this to the United States, where the average adult engages in less than ten minutes of moderate to vigorous activity a day, and physical activity peaks at age six.

Real-time tracking also shows that people are happier during moments when they are physically active than when they are sedentary. And on days when people are more active than their usual, they report greater satisfaction with their lives.

Leave the fossil record aside and you can observe many features in your own physique that help you run. Large gluteal muscles and longer Achilles tendons propel us forward. Compared to other primates, humans have more slow-twitch muscle fibers, which resist fatigue, and more mitochondria in running muscles, allowing them to consume more oxygen as fuel. We are also the only primate to have a nuchal ligament, the strip of connective tissue that fixes the base of the skull to the spine. This ligament—shared by other running species, such as wolves and horses—keeps your head from bobbing when you run. All of these adaptations suggest that we evolved as endurance athletes. Because the survival of early humans depended on traveling far and fast, you were born with bones, muscles, and joints that help you go the distance.

Earlier research had hinted that exercise might trigger a release of these brain chemicals, but no one had ever documented it during running. So Raichlen put regular runners through treadmill workouts of differing intensities. Before and after each run, he drew blood to measure endocannabinoid levels. Walking slowly for thirty minutes had no effect. Nor did the most intense workout, running at maximum effort. Jogging, however, tripled the runners’ levels of endocannabinoids. Moreover, the elevation in endocannabinoids correlated with the runners’ self-reported high. Raichlen’s hunch was correct. The runner’s high is a buzz.

the key to unlocking the runner’s high is not the physical action of running itself, but its continuous moderate intensity.

Anything that keeps you moving and increases your heart rate is enough to trigger nature’s reward for not giving up. There’s no objective measure of performance you must achieve, no pace or distance you need to reach, that determines whether you experience an exercise-induced euphoria. You just have to do something that is moderately difficult for you and stick with it for at least twenty minutes. That’s because the runner’s high isn’t a running high. It’s a persistence high.

Among married couples, when spouses exercise together, both partners report more closeness later that day, including feeling loved and supported.

Could the afterglow of physical activity make you feel more warm and fuzzy about the people you share your life with?

And the more physically active you are, the more rewarding these experiences become. That’s because one of the ways that regular exercise changes your brain is by increasing the density of binding sites for endocannabinoids. Your brain becomes more sensitive to any pleasure that activates the endocannabinoid system; it can take in more joy. This includes the runner’s high, which helps explain why people find exercise more enjoyable the more they do it. But it also includes social pleasures, like sharing, cooperating, playing, and bonding. In this way, regular exercise may lower your threshold for feeling connected to others—allowing for more spontaneous feelings of closeness, companionship, and belonging, whether with family, friends, or strangers.

This phenomenon—known as attention capture—reveals a brain always looking for an opportunity to indulge a favored habit.

And for many of us—myself included—getting hooked on exercise points not to its inherently addictive nature, but to our brain’s capacity to latch onto a relationship that is good for us.

One study of new members at a gym found that the minimum “exposure” required to establish a new exercise habit was four sessions per week for six weeks.

Exercise enthusiasts report their own versions of the pleasure gloss and cue-dependent cravings. Sensations associated with exercise become highly pleasurable, and objects, places, or other cues related to a favorite activity can produce a strong desire to move.

Exercise produces a less extreme spike in dopamine, endorphins, and other feel-good chemicals. Drugs like cocaine or heroin wallop the system, but exercise merely stimulates it, leading to very different long-term adaptations. The brain reacts to regular exercise not by suppressing activity in the reward system, but by facilitating it. In direct contrast to drugs of abuse, exercise leads to higher circulating levels of dopamine and more available dopamine receptors. Instead of annihilating your capacity for pleasure, exercise expands it. The sensitization of the reward system to nondrug rewards such as food, social connection, beauty, and any number of ordinary pleasures may explain why exercise helps people recover from substance abuse.

A meta-analysis of twenty-five randomized clinical trials concluded that exercise has a large and significant antidepressant effect among people diagnosed with major depressive disorder. Another review of thirteen studies—conducted in the U.S., the UK, Brazil, Germany, Norway, Denmark, Portugal, Italy, Spain, and Iran—found that adding exercise to treatment with antidepressant medication leads to larger improvements than medication only.

Super-runners have physically larger midbrains, including the structures of the reward system. They also show differences in gene expression and neurotransmitters throughout the reward circuit.

Scientists who study social relationships have discovered that trust is a self-fulfilling prophecy. People who are viewed as trustworthy act in more generous and dependable ways. This becomes further evidence of their trustworthiness, and people trust them even more.

In The Anatomy of Hope, physician Jerome Groopman defines hope as “the elevating feeling we experience when we see—in the mind’s eye—a path to a better future.” Hope

Psychologists call physical activity that takes place in a natural environment green exercise. Within the first five minutes of any physical activity in nature, people report major shifts in mood and outlook. Importantly, they don’t just feel better—they feel different, somehow both distanced from the problems of everyday life and more connected to life itself.

Unlike a runner’s high, the mind-altering effects of green exercise kick in almost immediately. These fast-arriving benefits cannot be explained by the slow accrual of feel-good chemicals like endocannabinoids or endorphins. Instead, it’s as if being in nature flips a switch in the brain to transport you into a different state of mind.

the psychological benefits of being in nature are most pronounced among those who struggle with depression. It is also a reminder that making time for physical activity is not self-indulgent. For many, it is an act of self-care, even self-preservation. In his memoir Dip, photographer Andrew Fusek Peters—whose father died by suicide—explains how swimming in the rivers, lakes, and waterfalls of Shropshire and Wales interrupted the usual “thought-torture” that defined his own severe depression: “Diving into wild water is the great bringer-back of reality. A perfect present tense, a right-here, right-now moment.

that two pressures shaped the development of the human brain. The first was our need to cooperate in small groups.

The second pressure on human evolution was our need to cooperate with the natural environment to find food.

Spending time not just indoors, but also on social media, pushes us toward social cognition and, often, rumination. Without regular time spent outdoors, we can lose touch with the default state of open awareness.

Natural environments have the ability to instill feelings of what researchers call prospect—an elevated perspective and hopefulness, often triggered by natural beauty or awe-inspiring views—and refuge, the sense of being sheltered or protected.

individuals who feel a stronger connection to nature report greater life satisfaction, vitality, purpose, and happiness. People who make more frequent visits to natural spaces are also more likely to feel that their lives are worthwhile.

E. O. Wilson, the biologist who argued that humans have a hardwired need to connect with nature, also observed, “People must belong to a tribe. They yearn to have a purpose larger than themselves.”

Ultra-endurance athletes have a relationship to suffering that separates them from most recreational exercisers and that often resembles the wisdom of spiritual traditions.

Learning to carry on in such a state is something that stays with you. Jennifer Pharr Davis, who in 2011 set the fastest known time for hiking the Appalachian Trail (46 days, 11 hours, and 20 minutes), writes in The Pursuit of Endurance that one of the most important things she’s learned is, “You don’t have to get rid of the pain to move forward. The hurt we experience in life might never fully go away; it could ebb and flow for an eternity. You can make progress and appreciate the times when life isn’t as much of a struggle. And you can pray, and cry, and wrestle through the rest.”

To an outside observer, it might seem as though these psychological strategies are a means to an end, mental skills you need to perform the task of physical endurance. But when you listen to athletes, it’s not at all clear that’s how they perceive things. Many seem to take the reverse perspective: The physical hardship is the means to cultivating the mental strengths.

If endurance training is in part about learning how to suffer well, it helps to put yourself in surroundings that inspire awe or gratitude. Outdoors, you can be stunned by a sudden change in landscape or enthralled by the appearance of wildlife. You can find yourself entranced by the stars at night or heartened by the first light of dawn. These transcendent emotions put personal pain and fatigue in a different context.

“Each runner was responsible for allowing hope to get the better of despair,” Burroughs writes. “Hope is what makes active endurance possible.” The ability of ultra-endurance athletes to keep moving forward can be at once inspiring and bewildering.

Irisin is best known for its role in metabolism—it helps the body burn fat as fuel. But irisin also has powerful effects on the brain. Irisin stimulates the brain’s reward system, and the hormone may be a natural antidepressant. Lower levels are associated with an increased risk of depression, and elevated levels can boost motivation and enhance learning.

A 2018 scientific paper identified thirty-five proteins released by your quadriceps during a single hour of bicycling. Some of these myokines help your muscles grow stronger, while others regulate blood sugar, reduce inflammation, or even kill cancer cells. Scientists now believe that many of the long-term health benefits of exercise are due to the beneficial myokines released during muscle contraction.