Regular exercise reduces the risk of developing Covid-19 or becoming seriously ill with the disease, with about 20 minutes a day providing the most benefit, a global analysis of data suggests.
Regular physical activity is associated with a lower risk of COVID-19 infection, severity, hospitalization and death, according to new pooled data analysis of available evidence published in the British Journal of Sports Medicine.
A weekly total of 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity physical activity appears to provide the best protection, the study suggests.
“Regular physical activity appears to be related to a lower probability of adverse outcomes from covid-19,” the team of Spanish researchers wrote. “Our analysis reveals that people who engage in regular physical activity have a lower probability of Sars-CoV-2 infection, Covid-19 hospitalization, severe Covid-19 illness, and Covid-19-related death than physically inactive people, regardless of the design and instrument used.
Experts know that regular exercise has a protective effect against the severity of respiratory infections.
Regular physical activity is associated with a range of health benefits, including reduced incidence of risk factors for adverse outcomes from Covid-19, such as being obese or having type 2 diabetes.
However, due to the limitations of the analysis, the findings should be interpreted with caution, the researchers said.
Previous research suggests that physical activity may decrease both the risk and severity of respiratory infections due, at least in part, to its ability to stimulate the immune system.
The link between regular physical activity and COVID-19 severity is not well understood, but likely involves both metabolic and environmental factors, say the researchers, who set out to try to quantify the threshold of physical activity that might be needed to decrease the risks of infection. and associated hospitalization and death.
They searched major research databases for relevant studies published between November 2019 and March 2022. From an initial search of 291, they pooled the results of 16.
The studies included a total of 1.8 million adults, just over half of whom (54%) were women. The average age of the participants was 53 years. Most of the studies were observational and took place in South Korea, England, Iran, Canada, UK, Spain, Brazil, Palestine, South Africa, and Sweden.
Pooled data analysis showed that, overall, those who included regular physical activity in their weekly routine had an 11% lower risk of infection with Sars-CoV-2, the virus that causes covid.
They also had a 36% lower risk of hospital admission, a 44% lower risk of severe illness from COVID-19, and a 43% lower risk of death from COVID-19 than their physically inactive peers.
The maximal protective effect occurred at approximately 500 minutes per week of metabolic equivalent of task (MET), after which there was no further improvement.
METS expresses the amount of energy (calories) expended in one minute of physical activity; 500 of them equals 150 minutes of moderate-intensity physical activity or 75 minutes of vigorous-intensity physical activity.
The researchers cautioned that the analysis included observational studies, different study designs, subjective assessments of physical activity levels, and referred only to Beta and Delta variants of Sars-CoV-2 rather than Omicron, all of which could weaken the results. findings.
There are plausible biological explanations for what they found, the researchers said. Regular moderate-intensity exercise can help boost the body’s anti-inflammatory responses, as well as cardiorespiratory and muscular fitness, all of which may explain its beneficial effects on COVID-19 severity, they suggest.
“Our findings highlight the protective effects of engaging in sufficient physical activity as a public health strategy, with potential benefits in reducing the risk of severe COVID-19,” they wrote. “Given the heterogeneity and risk of publication bias, more studies with standardized methodology and reporting of results are now needed.”
