If You Smell This at Your Gym, You Should Leave, Warns Top Scientist

It's a cruel irony that one of the safest and healthiest things we can possibly do instantly became one of the most dangerous during the era of COVID. Hardcore fitness classes—spinning classes, HIIT circuit classes, Zumba raves, you name it—may get your heart rate pumping and ultimately help you lose weight, be happier, and live longer, but they're also usually conducted in window-less gym rooms where people breathe extra hard and propel viral particles farther than they would if they were doing basically anything else.

In just one example from last year, an entire cycling class in Hawaii that followed social-distance protocols contracted the virus. "Among epidemiologists, that's known as a 100 percent attack rate," observes The New York Times.

Today, as more and more Americans are being vaccinated, many gyms are starting to open their doors to lower-capacity fitness classes once again. The question remains: Is it too soon to hit up your favorite class, whether you're vaccinated or not? The Times sought out the advice of Linsey Marr, Ph.D., an engineering professor at Virginia Tech who became an unlikely celebrity in 2020 thanks to her expertise in a niche but quickly relevant field: viral transmission. Turns out she's also a CrossFit enthusiast, and she actually consulted with her local gym instructor, "examining building plans and calculating potential class size and ventilation patterns in the facility," according to the Times.

Given the heavy breathing involved in exercise, Marr recommended that exercisers be socially distanced at 10 feet from each other, not just 6 feet. She also had them install and use retractible garage doors to improve ventilation. They used carbon dioxide monitors to monitor the air. She says that masks are only so much help, especially after they get sweat in them. "The level of protection provided by masks is so variable that we cannot rely on them alone," she said.

The gym was able to reopen safely with no known COVID cases to date. But it's safe to say that most gyms don't have help of the world's foremost expert on viral transmission in redesigning their layouts. So Marr also revealed a few good signs and bad signs that you should look for at the fitness classes at your gym.

High ceilings? That's an encouraging sign. Open windows on opposite sides of the room? Also good. But if you pick up a whiff of one thing, take note—it's a surefire indicator that you're working out in a room that is poorly ventilated.

"If you can smell someone else, that's a bad sign," she explained to the Times.

So bear this in mind the next time you're feeling like you need to hit up Barry's Bootcamp. After all, they're open for business again—and not just virtually. And for more great fitness advice you can use, make sure you're aware of The Super-Quick Workout That's Scientifically Proven to Work, Says Mayo Clinic.