Is It Really Safe to Exercise Outside?
The coronavirus pandemic has forced millions to stay inside in an effort to flatten the curve. But even under stay-at-home orders, people can go outside to exercise, as long as they stay six feet away from others.
In fact, many experts encourage it. In addition to exercise’s well-known health benefits such as maintaining a healthy weight and reducing the risk of chronic disease, going outside for a walk, run or other activity can also help alleviate pandemic-induced anxiety. “There is a risk of your mental health deteriorating during this period,” says Daniel Brian Nichols, associate professor in biological sciences at Seton Hall University. “I think it’s important that people do get outside and enjoy the weather and exercise.”
Here, scientists address the biggest concerns about exercising outside in times of Covid-19.
While he agrees that runners and pedestrians en route should adhere to the six-foot guidance whenever possible, he says they’ve got a bit of breathing room.
Is it okay to be less than six feet away from someone while running past them?
The novel coronavirus can spread between people in close contact, which the Centers for Disease Control and Prevention defines as “within about six feet” (think the length of a mattress). Public health officials have urged people to maintain this distance, even while exercising. In theory, if someone exposed to the virus coughs or sneezes, passersby could inhale those respiratory droplets and contract the virus.
Let’s be real. It’s one thing to stand six feet apart while waiting in line at the supermarket, but if you’re outside on a run or walk, you’ll probably be passing people in closer proximity, especially on a small city street or a narrow path in a park.
Nichols, who studies virus-host interactions, says runners are most likely safe to pass each other for a split second, even if it’s within six feet. While he agrees that runners and pedestrians en route should adhere to the six-foot guidance whenever possible, he says they’ve got a bit of breathing room when they pass each other.
“Most of the virus is in the heaviest droplets, which tend to fall out within about a meter (3.3 feet) from a person, so it’s very unlikely that you would be able to cough or sneeze over six feet and actually transmit the virus, especially outside,” he says.
That said, the research is still out on how far the finest particles spread when someone coughs, sneezes, or exhales. For that reason, Nichols says it’s best to be overly cautious and avoid areas like small public parks on a sunny afternoon, where it’s difficult to keep a safe distance.
An important question about exercising outside is whether breathing heavily impacts that droplet radius. But since research on SARS-CoV-2 is in early stages, scientists don’t know the answer. “When people are running and breathing heavily, if they are incubating the virus they may be able to spread it farther, but we just haven’t tested that yet,” says Tara Smith, a Kent State University epidemiology professor.
“The published papers so far don’t suggest that a brief interaction with a person passing you is very risky,” says Smith. Even so, she suggests that runners do their best to maintain a safe distance during the majority of the route. “I’d use six feet as a minimum and try to stay as far away as possible,” she says.
So, what’s the bottom line? Overall, runners should balance concerns over the coronavirus with personal safety: Do your best to maintain a six-foot distance while passing other runners, but don’t stress if you need to pass someone at a closer range (unless they are coughing or sneezing). “Don’t get hit by a car trying to avoid a person,” Smith says. If crossing the street feels awkward or dangerous, swerving or stepping out of the way will do (don’t forget to smile).
An important question about exercising outside is whether breathing heavily impacts that droplet radius. But since research on SARS-CoV-2 is in early stages, scientists don’t know the answer.
Can you get the coronavirus through the air outside when other people are around?
Since people can carry the virus without showing symptoms, another worrying scenario has emerged: A person who’s unknowingly infected might go for a run in a park and cough or sneeze, leaving behind tiny droplets laden with the virus, which early evidence suggests can remain suspended in the air for short periods of time.
Does that mean people should be concerned about running through someone else’s infectious droplets? “It’s possible, but I think unlikely,” Smith says. “Just because something can be in the air doesn’t mean there’s enough of it there to actually cause infections — that’s something that we’re still trying to figure out,” she says.
In March, a new study published in NEJM found SARS-CoV-2 remained infectious in aerosols for three hours under laboratory conditions; this translates to about a half-hour under normal conditions, the New York Times reports (although the World Health Organization maintains that the risk of airborne transmission is low).
According to Nichols, it’s even less likely that the virus would remain infectious outside in a public park, where wind, fluctuating temperatures, and UV radiation might affect airborne transmission. It’s much more of a concern for medical workers, who are performing procedures on infected patients in close proximity.
What about surfaces a runner encounters outdoors?
The same NEJM study found SARS-CoV-2 on plastic and stainless steel 72 hours after it was first applied. These findings suggest that the virus also sticks on surfaces that people might touch outside: pedestrian “walk” signs, benches, playground equipment.
“Be reasonable,” Smith says. “You need that walk sign.” But constantly remind yourself to not touch your face, even when you’re sweating. “This might be a good time for sweat bands if you have them, to put on your wrists or forearms to wipe away sweat from your face. And use an elbow to touch walk signs if you can.” And of course, wash hands with soap and water for at least 20 seconds afterwards.
Nichols also advises runners to bring their own water, rather than use a public drinking fountain. “If somebody with the infection touches that, and you touch it and scratch your eyes or nose, you could inoculate yourself,” he says.