The scientists expected that athletes’ aerosol production would increase as intensity increased. We all breathe deeper and faster as we exercise more. But the extent of the increase “surprised us,” said Henning Wackerhage, a professor of exercise biology at the Technical University of Munich and lead author of the new study.
The increase in aerosol emissions started off modestly as cyclists warmed up and started pedaling harder. But as they reached a threshold where their exercise became noticeably more strenuous—about the time jogging turns into a run or a spin class switches to intervals—the increase in emissions became exponential. The cyclists began inhaling about 10 times more air per minute than at rest, while the number of particles per minute shot up more than 100 times as the cyclists approached exhaustion (with considerable variation from person to person). .
In a room full of spin cyclists, treadmill runners or campers, “the concentration of aerosol particles would increase a lot,” said Benedikt Mutsch, a graduate student at the Institute for Fluid Mechanics and Aerodynamics at the University of the German Armed Forces. . in Munich and co-author of the study. The more particles, the more possibility of infection by Covid-19, if any athlete is infected.
“The study provides mechanistic data to support the assumption that exercising indoors is a higher risk activity when it comes to COVID-19 transmission” than exercising outdoors, said Linsey Marr, a professor of civil engineering and environmentalist at Virginia Tech. and an expert in airborne transmission of viruses.
But these risks can be mitigated. “Good ventilation and air exchange is a great way to reduce the risk of transmission,” said Chris Cappa, a professor of civil and environmental engineering at the University of California, Davis, and an expert in airflow dynamics.
“Open windows, especially with fans, can often be just as effective as active ventilation systems,” he said. If your gym windows are closed, ask the manager to open them wide and turn up the volume on the fans. If the weather is sweltering and air conditioning is needed, make sure your gym units draw air from outside, so fresh supplies replace air filled with aerosol emissions from you and your classmates.
You can also suggest that the gym install room air filters in each workout area, Dr. Cappa said. “These can be really effective in reducing the risk of transmission by removing the virus from the air.” They can be commercially purchased or even Homemadehe said.
