COVID-19 spreads easily in gyms, CDC finds. Here's how you can work out safely indoors.

If you're going to work out at an indoor gym, you — and everyone around you — needs to be wearing a mask. That's the message sent by the Centers for Disease Control and Prevention this week in two reports detailing outbreaks at workout facilities, both of which occurred due to lack of adequate protections.

The first transpired at a Chicago exercise facility, where 55 of 81 people who attended indoor high-intensity classes tested positive for COVID-19. The classes were held between Aug. 24 and Sept. 1 and although the facility mandated masks upon entry, patrons were allowed to remove the masks during class. The 55 cases were traced to two different individuals, both of whom attended classes while symptomatic.

The second outbreak involved 21 cases across three fitness studios in Hawaii, many of them linked to a single 37-year-old male fitness instructor who developed symptoms after teaching classes at two of the facilities. The Hawaii Department of Health investigated the cluster of cases and found that lack of mask-wearing and the instructor shouting for 60 minutes (during a spinning class) likely fueled the cases.

So is it really OK to workout indoors — and if so, how can you do it safely? Here's what you need to know.

After two new CDC reports detailed COVID-19 outbreaks at gyms in Chicago and Hawaii, experts share tips on how to workout safely indoors. (Photo: Getty Images)
After two new CDC reports detailed COVID-19 outbreaks at gyms in Chicago and Hawaii, experts share tips on how to workout safely indoors. (Photo: Getty Images)

Recognize that risks vary based on the type of workout you plan to do

In the time of COVID-19, not every workout is created equal. Yahoo Life Medical Contributor Dr. Dara Kass says it's important to think about how easily the virus could spread based on the type of activity you're doing. "Doing static activity at a gym masked up and distanced is not the same risk profile as doing a high-intensity aerobics class without a mask," says Kass. "People need to look at ... how far those respiratory droplets will travel and what barriers they have themselves to inhaling somebody else's respiratory droplets."

In both places the CDC studied, high-intensity workouts without masks were key to the virus's spread. That's what Kass says to avoid. "When you think about certain indoor athletic classes and you turn the lights down and see all that spit flying, you probably don't want to be there," she says. "It's kind of gross to have to think about it like that but you have to think that way." She recommends considering things like yoga or barre class while masked, or lifting weights with a mask while distanced from others — all activities that she classifies as "low risk."

If you're feeling symptoms, stay home

Dr. Amesh Adalja, senior scholar at the Johns Hopkins Center for Health Security, says one important note is that anyone who feels remotely ill should avoid any indoor facilities — especially fitness studios. "You should not be going there if you are sick or have any symptoms that are consistent with coronavirus or you're waiting for a test result, or have been identified as a significant exposure," Adalja tells Yahoo Life. "Going to the gym when you're symptomatic makes zero sense in the middle of a pandemic. It's actually dangerous to do that to other people."

Bring a mask and wear it the entire time — even during high-intensity workouts

One of the CDC's main takeaway from the outbreaks is that mask-wearing needs to be mandatory. "To reduce SARS-CoV-2 transmission in fitness facilities, staff members and patrons should wear a mask, and facilities should enforce consistent and correct mask use (including during high-intensity activities)," the CDC writes.

Adalja agrees. "It's clear when you exercise, you're going to be exhaling a lot more; you're going to be breathing more vigorously. And we know that that will make you more contagious if you are somebody that happens to harbor the virus," he says. "So having a mask policy that people are wearing masks throughout the gym, that's going to be really important. Even when they're at their individual machines they still should be wearing a mask and that will help decrease the level of contagion that occurs."

Stay at least six feet apart and pay attention to ventilation

After a cluster of cases erupted at the Hawaii fitness studio, the facility decided to remove several bikes in order to space them out, then added plexiglass barriers between them. These precautions, along with proper ventilation, can significantly lower the risk of infection. "Try to keep social distancing in place," says Adalja. "Gyms that can use outdoor spaces or can open a window, all of that is going to be useful in decreasing spread."

If possible, opt for an outdoor workout or one you can do at home

While the CDC provided guidance for fitness studios and patrons regarding indoor workouts, the authors concluded that, "exercising outdoors or virtually could further reduce SARS-CoV-2 transmission risk." Both Kass and Adalja said they would recommend opting for either an outdoor class or one you could do at home, but neither think that a low-risk trip to the gym is out of reach. "I think it is possible to go to indoor gym safely if people recognize that we're in a pandemic," says Adalja. "You have to have certain mitigation measures in place to make it safe."

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