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If you brave the winter chill (safely, of course), you could also reap these rewards.

There’s no shame in hitting the treadmill when conditions get tough—not only is the moving belt free of slippery ice, but indoor running is also a great way to train for a fast 5K, hone your pacing, or give your joints a break from pounding cold, hard pavement.

However, provided you feel safe, there’s an upside to logging miles al fresco in the colder months, says Kimberley Dawson, Ph.D., a mental performance consultant and professor at Wilfrid Laurier University in chilly Waterloo, Ontario, Canada. Many of the Olympians and other runners she works with describe winter running as a simultaneously soothing and invigorating experience—“like a cleanse,” she says.

There are a few caveats to consider before heading out in the cold. Exercise physiologist Daniel Craighead, Ph.D., an assistant research professor at University of Colorado Boulder, is careful to point out you should always protect yourself from the elements. “Layer up to keep your core temperature in a normal range and avoid hypothermia,” and also to ward off frostbite, he says.

There are other risks: Inhaling cold air can trigger bronchospasms, asthma-like bouts of coughing and wheezing that hamper breathing. And elevated blood pressure in the cold could lead to heart attacks, especially in older people or those with underlying heart conditions. That’s one reason shoveling snow sends so many people to the emergency room. The risk is lower with running, especially for those who do it regularly, but still worth acknowledging, he says.

Regardless of your baseline health, there are some days when conditions might warrant staying inside. There’s no single cutoff temperature that’s dangerous, because wind, precipitation, and sunlight play a role. Instead, Craighead recommends checking your local weather forecast and heeding windchill advisories and frostbite warnings. Additionally, consider how much ice is on your route; slipping and injuring yourself could keep you inside for much longer than you intend.

But on days that don’t pose those dangers, consider gearing up and getting out there to reap the benefits of winter running. Besides psychological sensations like peace and clarity, braving the elements comes with some physical perks, too. Here’s more on why cold-weather training just might be worth it.

On the first frigid day of each season, your sympathetic nervous system swoops into action, revving up your fight-or-flight system to save you from freezing. Your blood shuttles inward from your skin and extremities to preserve your core temperature and your vital organs, says Craighead. And if you weren’t generating heat by running, you might start shivering.

But as you repeatedly encounter cold weather with no life-threatening consequences, your body learns to tone down its stress response, a somewhat mysterious process called cold habituation. As winter wears on, fewer stress hormones, such as catecholamines, flow through your bloodstream. And more of that blood stays close to your skin, making you feel warmer.

Unlike heat acclimatization, cold habituation has no proven performance benefits; nor does it seem to add to the health perks you’re already getting from exercise, Craighead says. However, regular runs can speed the adjustment process, making any other outdoor task—from walking the dog to waiting for the bus—more bearable.

Millions of Americans—especially those who live in northern climates—notice that their mood dips in colder months. Health experts believe one key reason for this condition, called seasonal affective disorder, is that less exposure to natural light throws off our circadian rhythms.

Training outdoors during daylight can help reset those rhythms, says Paul Winsper, Under Armour’s VP of Human Performance, Science and Research. Sunlight exposure also increases production of vitamin D, a key component of mood-regulating neurotransmitters like serotonin (and, Winsper points out, critical to a healthy immune system).

Add to this the mood-boosting effects of both physical activity and exposure to green space, and cold-weather running can serve as a salve, Dawson says—an antidote for “nature deficit disorder,” a term coined by author Richard Louv to refer to disconnection from the world around us. In addition, exercising outdoors may also decrease fear and uneasiness; in one large 21-year study, Swedish cross-country skiers were about half as likely to develop anxiety as non-skiers.

All of this is particularly critical right now, with an ongoing pandemic that has worn away at our collective mental health. “When you look at what COVID has taken away from us, it’s really taken away our sense of control,” Dawson says. “We get that back when we are outside, when we are one with nature, and we are grounded.”

Of course, for many people, outdoor running alone isn’t enough to treat seasonal depression, anxiety, or other mood disorders. It’s still a good idea to talk with your doctor or a mental health professional if sadness, hopeless, or anxious thoughts interfere with your daily activities. And if you’re in crisis, you can call the National Suicide Prevention Lifeline toll-free at 1-800-273-TALK (8255) or text “HELLO” to 741741.

Shivering definitely increases your body’s energy expenditure, but if you’re running, your core temperature probably won’t drop enough for you to start shaking. However, research suggests less significant drops in body heat can trigger a phenomenon called nonshivering thermogenesis, an increase in metabolism mainly accomplished through the activation of special tissue called brown fat. (There’s even some evidence this effect increases as you become habituated to the cold.)

“As the weather is colder, people tend to be less active,” Craighead says. Add pandemic-related restrictions and routine changes, and many people have been moving even less over the last two years. The one-two punch of exercising and colder air can keep your body’s fueling systems humming along.

Say you’re training for a spring race—for instance, the Boston Marathon, which in 2022 returns to its traditional third Monday in April. The weather for these events can be unpredictable, as anyone who ran Boston in 2018 can tell you. Persevering through less-than-ideal conditions in training can prepare you to cope with any forecast come race day, Dawson says.

“You get this really nice sense of, I am mentally tough, I can do this,” she says. “If I can navigate this, then I can navigate that spring marathon in terms of whatever it throws at me.”

The chemical reactions that produce muscle contractions function best at warm temperatures, meaning you can’t always perform as well in frigid conditions, Craighead says. That, combined with the extra challenge of ice or slush, means you can stress less about putting up a good pace on Strava.

“When it’s a sunny day and conditions are ideal, you think, ‘I need to really take advantage of that,’” Dawson says. “I love a winter day because it demands nothing. It simply says that success is getting out the door.”

Of course, some people have an easier time backing off than others: “I always liked running in the snow, because I didn’t have to worry about what pace I was running,” says Craighead, who competed at Ithaca College in New York. “But then I’ve had teammates who freak out when they see a really slow time on their GPS watch and go too hard.”

If you’re still hung up on numbers, consider leaving your watch behind or running by time alone, Dawson suggests. Many runners she works with strike a balance by doing tempo runs or interval workouts on the treadmill, then doing long runs and easy runs outdoors. She also suggests being creative with your route: “For me, I run around the cemetery because it’s the first road to get plowed,” she says—plus, it’s peaceful and quiet.

Or, take on an entirely different challenge. When the drifts pile up, Craighead turns to snowshoe running, wearing lightweight shoes specifically designed for the sport. Not only does it offer another chance to compete, research suggests the fitness gains transfer directly to running. “Some of my best track seasons, back when I used to do track every spring, came after winters have more snowshoe running,” Craighead says.