In-Depth: Exercise has dramatic impact on severity of COVID-19 cases

New report shows link between illness and activity
Posted at 5:56 AM, Apr 21, 2021

SAN DIEGO (KGTV) - A new report in the British Journal of Sports Medicine says that, aside from vaccination, exercise "may be the single most important action individuals can take to prevent severe COVID-19 and its complications, including death."

The report, written by doctors at Kaiser Permanente with help from researchers at UC San Diego and Pomona College, was published earlier this month.

In the study, doctors used medical records of 48,400 Kaiser Permanente patients who tested positive for COVID-19. The data included two years' worth of information about how often those people exercised and for how long.

Researchers sorted the patients into three groups:

  • People who exercised 10 minutes or less per week.
  • People who exercised 11-149 minutes per week.
  • People who exercised 150 or more minutes per week.

They found people in the first group, called "Inactive Patients," had much more severe reactions to COVID-19 than people in the other two groups.

"What we found, not surprisingly, was that there was a significant effect of being sedentary," says Kaiser Doctor Robert Sallis, the lead author of the study.

According to the results, when controls were in place for all other factors, "Inactive Patients" were:

  • 2.26 times more likely to be hospitalized by COVID-19
  • 1.7 times more likely to need ICU care, and
  • 2.5 times more likely to die from COVID-19 than people in the most active group.

"To me, this is the culmination of a year of work to bring some data on what we believed a year ago - the power of physical activity. And now we have the data to show that power," says Dr. James Sallis from UC San Diego.

The study also found that inactivity was a more significant indication of risk for severe COVID-19 outcomes than any other underlying medical condition except for advanced age or organ transplant.

US Physical Activity Guidelines recommend 150 minutes of moderate or greater exercise each week, such as a brisk walk. However, CDC guidelines for COVID-'19 do not put physical inactivity in the "major risk" category.

Dr. Sallis from Kaiser says he hopes this study changes minds.

"Nobody seems to talk about the problem of physical inactivity, and I think it's been a real colossal error that we haven't included that," he says.

"At the same time, we are pushing people to distance, to mask, to get your vaccine. We haven't been pushing any need to be exercising."

He says the findings shed new light on decisions by health and government officials to close gyms, parks, and trails during the Pandemic.

"When when we're telling our patients to exercise, and they say well my gym got shut down I can't go to the park I can't go on the hiking trails, it's been very difficult," says Dr. Sallis.

"I hope this study will change some minds and open up some thinking in our public health officials and to what is important and what should we be key trying to keep open and available."

Public health officials issued the closures to prevent the spread of the disease. Dr. Sallis from UC San Diego says this study should help adjust policy going forward.

"We understood that they closed those things to reduce the transmission," Dr. Sallis says. "We felt that there were some benefits to closing down these places to be active. But there were probably some costs too. And we didn't have the data to try to understand that trade-off."

Dr. Sallis from Kaiser says this does not mean people can replace the need for a vaccine with more exercise. But he says it's an excellent reminder to stay active while you wait for a vaccine. He also says continued physical activity can help fend off severe cases if any variants prove to be vaccine-resistant.

"We can't just rest and say I got the vaccine. I don't have to do anything else," he says. "I think it's important for people to have something that they control that can positively affect (their) chances."

Both doctors believe exercise can also help increase the immune response from a vaccine. They say future studies will be needed to prove that.