Regular physical activity can help protect you from severe COVID-19 — and may even keep you from getting infected, according to review of the study posted on Aug 22 The British Journal of Sports Medicine.
“It’s time to look at exercise as medicine,” says co-author Yasmin Ezatvar, a doctor of physical therapy and nursing instructor at Spain’s University of Valencia. “This is more evidence that really backs that up.”
The researchers analyzed 16 previously published studies looking for links between physical activity and COVID-19 outcomes. These studies included a total of more than 1.8 million adults, and most relied on participants self-reporting their exercise habits. Most of the studies were conducted in 2020 and early 2021, before COVID-19 vaccines became widely available.
Compared to people who don’t exercise much, active people are about 36 percent less likely to be hospitalized and 43 percent less likely to die if they catch the virus. People who had at least 150 minutes of moderate-intensity exercise or 75 minutes of vigorous movement each week –the amount recommended by US public health officials– has the best protection, the researchers found.
In some ways, this finding is obvious. Exercise is consistent associated with good health and longevityand can help preventing or managing chronic diseases that put people at risk of complications from COVID-19, such as diabetes and heart disease.
More surprisingly, active people were also about 11 percent less likely to become infected compared to those who were more sedentary, the researchers concluded—suggesting that the exercise itself can be protective.
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“Regular physical activity can contribute to a more effective immune response,” says Ezzatvar. “May provide increased immunity to [many] infections, not just COVID.”
The paper does not provide proof that exercise causes these effects—only that it is associated with better outcomes from COVID-19. There may be other explanations for the trends, such as differences in lifestyle, exposure to viruses, and socioeconomic status between active and sedentary people. Most of the included studies were also published long before Omicron became dominant and when most people had not been vaccinated, so it is difficult to generalize the findings to the present.
Another potential caveat: If you happen to exercise next to someone who already has COVID-19, your exercise routine may not keep you from getting sick. A little research published in May found that someone doing high-intensity exercise gave off about 132 times more aerosols per minute than they did at rest—which is bad news if your neighbor on the treadmill has the virus.
Still, exercise is “100 percent” recommended for most people, Ezzatvar says. “It’s good for your health – not just for COVID [protection]but also your mental health and your physical health.”
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