Surprise: The happiest people in the world aren't those with loaded bank accounts, but rather the people who consistently log regular workouts. After analyzing data about the physical behavior and mental mood of over 1.2 million Americans, researchers at Yale and Oxford found that regular exercise is more important to good mental health than how much money you have.

In the study — published in The Lancet — the scientists discovered that people who make regular exercise a priority owned up to feeling bad about 35 days a year, while the non-active participants reported clocking up to an additional 18 days per year when they felt stressed or sad.

Related: 5 Tools Every Spartan Needs to Build Mental Strength and Resilience

The participants were also asked about their income, and the researchers found that the participants who were regularly physically active felt as good as those who out-earned them by $25,000 per year but didn't exercise.

The science also backs up what Spartans have been saying for years: People who exercise in groups or participate in sports with a social element, like a Spartan race, exhibit much greater mental health than those who exercise alone.

How Regular Exercise Boosts Happiness

All types of regular exercise — from mowing the lawn to running a marathon — were shown to reduce negative feelings by around 11 percent. But people who typically got their sweat on in group or team sports boasted an approximate 22 percent reduction in feeling stressed or depressed.

This shouldn’t surprise us, according to Josh Rundquist, CSCS, a Spartan SGX coach and certified strength and conditioning specialist based in Minneapolis, MN.

“Regular exercise increases the likelihood of the body releasing ‘happy’ chemicals such as dopamine, serotonin, and anandamide,” he said. “And team sports involve a higher level of human connection than individual sports do. Human connection is an often overlooked aspect of overall human health and wellness.”

Why Team Sports with Regular Exercise Matters

We live in a society where isolation — working in a home office or swapping face-to-face time for social interactions through a screen — is the norm.

“Team sports, like a Spartan race, give people a true space to interact with other individuals in a fun yet competitive way,” Rundquist said.

It’s a no-brainer that having those kind of interactions should make you happier.

Related: Can Racing Manage Stress? 5 Scientific Reasons Why

But — FYI — this study doesn’t you need to be exercising 24/7 to boost your mood. Participants who exercised between three and five times a week had better mental health than people who exercised less OR more each week, the study's authors said in a statement.

So there is a point when doing too much can start to be a source of stress in itself. And when exercise starts to mess with your mental state, you’re going to lose the happiness-boosting benefits that got you psyched to join that gym or sign up for that race in the first place.

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