In the UK, indoor gyms are allowed to reopen [1] starting 25 July, but many of us are still struggling to decide if it's worth going back [2]. Workout classes are especially up in the air. The government has released measures that gyms must follow, including ensuring adequate ventilation and limited class sizes, but groups of people working out in small studios still carries a high risk of coronavirus transmission, given what experts say about the virus being airborne [3] and the transmission potential of respiratory droplets [4] that leave our lungs when we cough, sneeze, or even exhale.

"There have been reports of outbreaks associated with exercise classes within gyms," said Anne Liu, MD, an immunologist and infectious disease doctor at Stanford. She cited research from May indicating that a cluster of coronavirus cases in South Korea could be traced back to dance fitness classes [5]. In total, researchers found 112 cases associated with classes in 12 different facilities. The researchers hypothesised that the large class sizes, small studios, and intensity of the workouts were what led to the high case count. "The moist, warm atmosphere in a sports facility coupled with turbulent air flow generated by intense physical exercise can cause more dense transmission of isolated droplets," they wrote. Interestingly, they noted that one infected instructor went on to teach Pilates and yoga classes of seven to eight students each, none of whom tested positive for coronavirus. They speculated that the lower-intensity of yoga and Pilates "did not cause the same transmission effects as those of the more intense fitness dance classes."

While this was a small case study, it makes sense given what we know about the coronavirus: that it spreads most potently from exhaled respiratory droplets, in indoor settings, with a larger number of people. Logically, the more and more heavily you breathe in an indoor setting, the greater chance you have of either passing on the virus or picking it up from someone else. "How people are breathing in that setting, whether they're wearing masks — all of that matters," Dr. Liu said. (Doctors note that while exercising with a mask on may be uncomfortable, it's recommended if you're exercising indoors with other people. Here are some breathable face mask styles [6] you can work out in.)

For now, Dr. Liu recommends working out outside, especially if you're in a group, and ideally six feet apart from each other to maintain social distancing [7]. "My hope is also that gyms try to use outdoor space, if they have access to it, to still do classes," she added. "People still want to go to classes. People still want to exercise. So, how can we bring together the gym staff with people, in a safer environment, even if it doesn't look like what they're used to?"

Of course, home workouts are also a safe and effective option, and you can even follow along with instructors in real time on platforms like Instagram Live or Active by POPSUGAR [8]. Though it might be a while before you're back in the studio with an instructor, there's plenty you can do at home (or outside) to keep moving.

POPSUGAR aims to give you the most accurate and up-to-date information about the coronavirus, but details and recommendations about this pandemic may have changed since publication. For the latest information on COVID-19, please check out resources from the WHO [9], the NHS [10], and GOV.UK [11].