COVID-19 has plagued the exercise rats. Even before scientists knew much about this particular virus, it became clear that breathing heavily in a confined space with many other people around doing so was an easy way to contract respiratory illness. The steam room and gym were among the first to close early. during the pandemic. These doubts have since been raised by science: aerosols – tiny droplets that spread through the air when we breathe – have identified as the main source of COVID-19 transmission, especially when people breathe faster and deeper. During the pandemic, exercise at turn class, fitness club and sport game has been identified as the source of dozens of new cases.
Now, a new test tells us more precisely how many sprays a person can spit out during an intense workout — and the results aren’t pretty. According to research by scientists in Germany published year PNAS on May 23, people emit 132 times more aerosols per minute during intense exercise than they do at rest, which researchers warn increases a person’s risk of contracting COVID-19 causing a flare-up. Super-spreading event. At rest, people emitted an average of 580 particles per minute, but during maximal exercise — in which the researchers gradually increased the intensity until the subjects were exhausted — people emitted an average of 76,200 particles. every minute.
The study authors acknowledge that their work has limitations. First and foremost, the sample size was only 16 people. In addition, none of the subjects were infected with COVID-19; In the paper, the researchers note that there is no way to do so safely, due to ethical concerns about the health risks to the participants.
However, there are some valuable findings to be drawn from the work. “[As an exercise physiologist]and we knew in advance that when you exercise, more air comes out of a person,” said Henning Wackerhage, co-author and professor of exercise biology at Technische Universität München. “But we didn’t know before, and what I didn’t expect, that was when we exercised hard: there were more particles per liter of air.”
The unusual experimental design allowed the researchers to get a more precise sense of the particles being released. While exercising on a stationary bike, each of the 16 subjects inhaled clean air through a silicone mask, then exhaled into a plastic bag. Christian Kähler, professor at the Institute of Fluid Mechanics and Aerodynamics at the Universität der Bundeswehr München, co-author of the study, said:
Some participants also emitted more aerosols during intense exercise than others; In particular, exercisers with extensive experience in endurance training emitted 85% more aerosols than those without such training. Dr Michael Klompas, a hospital epidemiologist and infectious disease physician at Brigham and Women’s Hospital, who was not involved in the study, explains that this may be a function that helps each person’s body become better. should be more efficient at moving large amounts of air. “They make their muscles do a lot of work, and they need to support that by providing the muscles with a large amount of oxygen and helping to get rid of waste,” he says.
If this gives you pause on your current workout regimen, remember that not all gyms are created equal — and the right policies and setups can help you stay safe. . For example, the amount of space per person is needed; Thomas Allison, director of the Cardiovascular Exercise Testing Laboratory at the Mayo Clinic, says large spaces, especially those with high ceilings, allow more space in the air. Other things to look for in a gym, Klompas says, are vaccination requirements, a facility that has professionally measured air flow and installed air filters, and ideally, a requirement to have it checked out. check. Masks are potentially useful, in Klompas’ opinion, but unlikely to be as reliable during workouts – looser masks won’t do as much during vigorous exercise and are impractical when expect people to wear an N95 during exertion.
The researchers note that factors besides physical condition can also affect the amount of aerosols people emit. Wackerhage said they are also looking at how factors such as body mass index, age and lung condition play a role.
Ultimately, says Klompas, whether or not you go to the gym depends on your risk tolerance and the individual costs and benefits of going to the gym. However, he says, you shouldn’t pretend that exercising in your home and around other people doesn’t pose a risk. “If you don’t want to get COVID, don’t go,” Klompas said. “At a time like now, when there’s a lot of COVID around, that’s a high-risk proposition.”
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