Messages in the US to "stay home" and "shelter in place" are poorly worded. Health professionals and city officials aren't discouraging people who are healthy from going outside and exercising.

When taking precautions, like keeping a safe distance from others and wearing a mask, spreading or contracting the novel coronavirus is highly unlikely in open air.

Even passing someone running or cycling within 6 feet would be an exceptionally unusual way to contract the virus, infectious-disease specialists say.

The mental-health and immune-system benefits of spending time outside outweigh the risks of spreading or contracting the virus.

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Don McCammon recently went for a run while wearing a mask in an uncrowded area of Orlando, Florida. The 40-year-old triathlete stayed not just 6 but closer to 15 feet away from any passersby.

That didn't spare him from criticism, though.

"I had a walker yell at me that I shouldn't be running during a pandemic," McCammon said. But the infectious-disease expert Anthony Fauci, New York Gov. Andrew Cuomo, and New York City leaders and public-health officials have said they go on regular jogs.

Roberta Pollack was running down a deserted road in Delavan, Wisconsin, when a driver took her to task. "They yelled that exercising wasn't a necessary thing, and I shouldn't be outside, and that I should get back inside before I get sick," she said.

Dozens of other runners, walkers, cyclists, and even open-water swimmers around the country told Business Insider about similar experiences, though just as many reported heartening anecdotes about strangers waving or politely getting out of the way.

The confusion about if and how you can get outside is understandable. Since the coronavirus outbreak began in the US, public-health messaging has been muddy, inconsistent, and constantly changing.

When communities issued shelter-in-place orders, people reasonably interpreted it literally, even though the fine print almost always said people could, and even should, go outside to exercise. And when staying home became a point of pride, some mental-health professionals said people were missing the point: Mother Earth is home too.

"Our research has found that nature is not an amenity — it's a necessity," Marc Berman, a psychologist at the University of Chicago who studies how environmental factors can affect the brain and behavior, said in a UChicago News story. "We need to take it seriously."

Especially now, as many Americans are well into their second month of a lockdown, we need to get outside for the sake of our collective mental and physical health. When taking precautions, the risks of spreading or contracting the virus in open air are slim, and the benefits of sun, movement, and physically distant human interaction far outweigh the virus' risks.

A woman in Battersea Park in London on March 21. REUTERS/Peter Nicholls

Transmission from a fleeting encounter is highly unlikely

There are safe and unsafe ways to get outside. Hanging out on a sidewalk corner with a cluster of people you don't live with? Not safe. Taking a maskless walk when you have symptoms of COVID-19, the disease caused by the coronavirus? Not safe.

Going for a solo run with a bandana you can pull up if you pass someone? That's pretty safe. Reading in your backyard alone even if you have COVID-19? Also safe.

"The general principle should be: Outside is better than inside; open is better than closed; fewer is better than more people; and stay away from sick people," Dr. Erich Anderer, a neurosurgeon and founding member of the North Brooklyn Runners, previously told Insider.

Even if you come within 6 feet of someone else for a fleeting moment, your chances of spreading or contracting the virus are slim.

"I would not worry about walking by someone," Dr. Amesh Adalja, an infectious-disease specialist at Johns Hopkins University, told Slate. "Even in a health-care setting, contact is defined by being near someone for a certain amount of time. I would not worry about these fleeting encounters. The virus isn't airborne — droplets need to get from one person to another."

Vox's Sigal Samuel wrote "a perfect sequence of events" would have to occur for someone to catch COVID-19 from a passing runner, walker, or cyclist.

You'd need enough particles to jettison out of a passerby's mouth or nose to survive the elements and land in your respiratory tract (or on your hands before you touch your eyes, nose, or mouth). Even then, the particles would need to sneak past your nose hairs and mucus and "dock up with your cells' ACE-2 receptors and use them to enter the cells," Samuel wrote.

That would take a lot of terrible luck to get someone sick. If both parties are wearing masks, it would be more like a freak accident.

The mental-health and immune-system benefits of the outdoors and exercise outweigh the risk

Time outside, and especially exercise outside, has phenomenal benefits for your mental health and immune function.

"I don't need to quote a study to let you know that if you've been inside all day, a little time outdoors will improve your mood," Dr. Jedidiah Ballard, an emergency-medicine physician, told Insider. "Vitamin D also plays a role in immune function, and sunlight is needed for our bodies to convert it to its active form."

One study of more than 1,000 adults, for instance, found that those who walked at least 20 minutes a day five days a week reported 43% fewer sick days than their less active counterparts. Even when the active people got sick, it wasn't as severe or as long-lasting, according to Harvard Health.

Zhen Yan, a professor of cardiovascular medicine who runs a molecular exercise physiology lab at the University of Virginia, has proposed exercise as a recommended measure alongside social distancing because his research suggests it may protect against acute respiratory distress syndrome, a top cause of death among COVID-19 patients.

"From a big-picture perspective, there are many studies in humans showing that cardiorespiratory fitness is inversely related to all cause of mortality," he told Business Insider. "In another word, the greater the exercise capacity, the greater the chance of survival under all circumstances, which presumably include COVID-19."

Even simply being outdoors but not moving much has impressive health benefits. Group nature walks have been linked to lower depression, less stress, and better mental health and well-being. Other research has shown that ​"forest bathing trips," or long stretches of time in the woods, can boost the number of white blood cells that fight viruses and tumors​.

"Just seeing the blue sky when you've haven't been outside your house for long periods of time has definite effects on mood," Sue Anne Bell, an assistant professor of nursing at the University of Michigan who studies the health effects of disasters, told Business Insider. "We're under a lot of stress and pressure in these highly unusual times, so going for a walk to clear your mind is really healthy for you — if you can do it safely."

Clean first, disinfect after. Getty

Not everyone has access to the great outdoors

Of course, it's easier to get outside safely if you live in a rural area or have access to loosely populated trails than if you live in a crowded city where park systems have closed.

It's up to city officials to find creative ways to allow residents to get outside while maintaining a safe distance, whether that's by shutting down some streets to cars or opening beaches and parks to walkers, runners, surfers, and swimmers.

And it's up to all of us to be smart and safe if and when they do — keeping a distance from others as much as possible, wearing a mask if you may come within 6 feet of someone else, continuing to wash your hands and surfaces diligently, and staying home if you're sick.

"When the weather is nice, think twice," Danielle Ompad, an epidemiologist at New York University's School of Global Public Health, told Business Insider when asked for a public-health slogan that for once would not be misinterpreted. "Enjoy the sun, but remember to protect yourself and others. We are all in this together."