Two new case studies by the CDC have found that indoor group fitness classes in Honolulu and Chicago led directly to COVID outbreaks that infected dozens of people — and the study authors caution that masks ought to be kept on at all times when gyms reopen, or people should keep opting for outdoor fitness.

Throughout the past year, business owners — and in particular gym owners — have been publicly arguing with elected officials and/or openly flouting pandemic health regulations by keeping gyms open. Keeping up with one's physical and mental health is important, they have argued, and they have demanded to see scientific evidence that gyms are dangerous vectors for the spread of the coronavirus.

As the New York Times reports, the Centers for Disease control has now published two cases studies, one out of Hawaii and one out of Chicago, that provide convincing links between group fitness classes in particular and the easy spread of COVID-19 when masks are not being worn. The studies confirm what had already been reported by the CDC early in the pandemic about an outbreak at a group fitness class in South Korea.

In the Chicago study, which looks at an outbreak that infected 55 out of 81 people who attended group fitness classes at one gym during a one-week span last August, researchers found that class attendees reported both inconsistent mask use and attending classes after experiencing COVID symptoms. Three attendees surveyed actually attended fitness classes on the same day or one day after receiving a positive COVID test result, because they were feeling no symptoms and they are morons.

These infections happened at a time when fitness classes in Chicago were limited to 10 to 16 people maintaining six feet of distance between them. However gyms were requiring masks coming in the door and temperature checks, but they were allowing people to remove masks while working out.

The Honolulu outbreak appears to be linked to one fitness instructor in particular, and the case study examines the rate of infectiousness between a period of two days and several hours before symptom onset. This 37-year-old male instructor, referred to instructor A, was found to be responsible for infecting 21 other people, including a second fitness instructor. Instructor A taught a 28-person yoga class a little more than two days before feeling ill, and no one in the class turned up positive for COVID. However this instructor taught a spinning class the next day for 10 people, and another spinning class on the day after that for 10 people, six of whom were the same as the previous 10. All 10 attendees of the spinning class on the third day — the day the instructor felt fatigue and other symptoms about four hours after the class — ended up testing positive for COVID, and all had been in the class without wearing masks.

The researchers suggest that in addition to inadequate ventilation and the lack of a mask policy, the instructor shouting commands while being highly infectious could also have contributed to infecting 10 out of 10 people in one class.

At the time of the outbreak, the Honolulu Star Advertiser reported that 17 cases had been tied to two gyms, and State Epidemiologist Dr. Sarah Park issued a statement saying that all indoor gyms "can be breeding grounds for all kinds of infections." And she said, "It is imperative that all gyms follow the safe practices required by state and county governments. These include proper physical distancing in work-out areas and in group classes, wearing of masks at all times, consistent and thorough disinfection of equipment and all surfaces." This suggests that these gyms had failed to enforce state mandates about mask wearing.

Gyms likely can operate relatively safely, with mask protocols, but for those craving group fitness, these studies suggest there's reason to hold off or only do it outdoors. A limited study of gymgoers in Norway last spring suggested that no COVID infections were linked to gyms that were practicing proper distancing, without masks, however there was very little virus in Norway at the time.

"Nothing is 100 percent safe," says Alex Larcom from the International Health Racquet and Sportsclub Association, speaking to the Times. "There is never zero risk. But [health] clubs are not the primary driver of COVID spread."

Larcom cites the irresponsibility of the fitness class attendees in Chicago who were either symptomatic or COVID-positive, and says, "Society-wide, we are relying on people who are sick or think they are sick to remove themselves from society."

Obviously, the moral of the story here is that humans are dumb and will continue to be dumb, especially but not only in America, so until you're vaccinated beware of mask-less spin classes and the coughing person two Stairmasters over.

Photo: Humphrey Muleba