Exercise is medicine, COVID study indicates
MONTREAL — What started as a catchphrase has become a movement that can no longer be denied. Physical activity has been prescribed by more and more physicians as a preventive measure against heart disease, high blood pressure, stroke, depression, Type 2 diabetes, and breast and colon cancer, and a study published in April in the British Journal of Sports Medicine offered another important example of why exercise is medicine.
“We found that consistently meeting physical activity guidelines was strongly associated with reduced odds for severe COVID-19 among infected adults,” said a team of researchers led by Robert Sallis from the Kaiser Permanente Medical Center in California.
It’s already accepted that exercise boosts immunity and that active individuals are less susceptible to viral infections and inflammation, both of which are hallmarks of COVID-19. But until recently there was little data linking the healthy effects of exercise to a reduced risk of the lifethreatening consequences of COVID-19. Searching for answers, Sallis and his team reviewed the health records of 48,440 individuals who tested positive for COVID-19 and were also patients of a healthcare system in southern California that routinely collected data on exercise habits.
Using the previously collected exercise data, the researchers classified the level of physical activity of each Covid-positive patient into one of three categories: consistently meeting physical activity guidelines (150 minutes or more of exercise per week), consistently inactive (zero to 10 minutes per week) or some activity (11 to 149 minutes per week). Comparing exercise volume against hospitalization, admission to the intensive care unit and death, and including the age, race, gender and medical history of all patients, they were able to take a novel look at the impact of exercise on the severity of COVID-19 symptoms.
“Those who were consistently meeting physical activity guidelines (150 minutes or more of exercise per week) were less likely to be hospitalized, admitted to the ICU or die related to COVID-19 than those who were consistently inactive or doing some activity,” stated the researchers.
Breaking it down even further, the odds of hospitalization increased 2.26 times for those who were consistently inactive compared to those who exercised 150 minutes per week. For those who did some activity, the odds of needing treatment were higher than the most active but less than the least active. Their chances of being hospitalized were 1.89 times greater than the most active patients in the study.
“It is notable that being consistently inactive was a stronger risk factor for severe COVID-19 outcomes than any of the underlying medical conditions and risk factors identified by the CDC (Centers for Disease Control and Prevention) except for age and a history of organ transplant,” said Sallis and his team. “In fact, physical inactivity was the strongest risk factor across all outcomes, compared with the commonly cited modifiable risk factors, including smoking, obesity, diabetes, hypertension, cardiovascular disease and cancer.”
Only 6.4 per cent of the study subjects consistently exercised for 150 minutes or more per week, and 14.4 per cent stated they exercised for 10 minutes or less weekly. The balance of the group placed themselves in the “some activity” group. The average body mass index of the group was 31.2, which is at the low end of the overweight category, and the average age was 47. Of the study subjects, 61.9 per cent were female. As for how many had severe cases of COVID-19, 8.6 per cent were hospitalized, 2.4 per cent were admitted to the ICU and 1.6 per cent died.
In light of these groundbreaking results, it’s ironic that physical activity is one of the lifestyle habits that has changed the most since the start of the pandemic. With gyms and recreation centres closed worldwide for a period of several weeks to several months during all three waves of the pandemic, and outdoor exercise severely curtailed, several studies have revealed that fewer people than ever are getting in 150 minutes of exercise per week. And despite prioritizing the opening of some recreation options after the first wave last spring, too few public health and government officials have been reaffirming the health benefits of getting in 150 minutes of exercise a week — something the researchers suggest should change.
“We recommend that public health authorities inform all populations that short of vaccination and following public health safety guidelines like social distancing and mask use, engaging in regular physical activity may be the single most important action individuals can take to prevent severe COVID-19 and its complications, including death,” stated the researchers.
Also missing are wholesale changes in how cities deliver recreation to constituents so that they can find safe ways to be active. The lesson for all of us, based on the data presented by Sallis and his team, is that when it comes to your health before, during and after a pandemic, it’s time to think of exercise as medicine.