Just 20 minutes of exercise a day could lower both the risk and severity of covid infection.
Small but regular amounts of exercise appear to reduce the risk of covid infection and severity, a major international analysis has shown.
The recent review, published in the British Journal of Sports Medicine, analysed 16 studies of almost two million adults and found that just 20 minutes of moderate intensity exercise each day appeared to reduce the risks of hospitalisation, severe infection and death from covid.
The analysis of these mostly observational studies found that people who exercised regularly had an 11% lower risk of infection compared to those that did not.
They also had a 36% lower risk of hospitalisation, 44% lower risk of severe covid infection and 43% lower risk of death than physically inactive subjects.
The analysis found that there was a dose-response relationship with exercise and protection from covid, but that the maximum protective effect kicked in at the equivalent of 150 minutes at moderate-intensity exercise per week or 75 minutes of vigorous intensity. No further improvement was noted for participants who exercised more.
“Our findings highlight the protective effects of engaging in sufficient physical activity as a public health strategy, with potential benefits to reduce the risk of severe covid-19,” the authors wrote.
While the included studies each used different designs and assessments of physical activity levels, the authors found that the effects still held.
“Our analysis reveals that individuals who engage in regular physical activity have a lower likelihood of SARS-CoV-2 infection, covid-19 hospitalisation, severe covid-19 illness and covid-19- related death than physically inactive individuals independent of design and instrument used.”
Because these studies included only Beta and Delta variants, not Omicron, the effects may be more muted in the current outbreaks.
Previous research has shown that regular physical activity offers some protection from respiratory infections and lessens their severity.
The authors speculated that one explanation for the results were the benefits that exercise had on metabolic fitness. Regular moderate-intensity physical activity contributed to improved cardiovascular and muscular fitness and could promote anti-inflammatory responses within the body, they said.
Most of these studies were carried out in South Korea, England, Iran, Canada, the UK, Spain, Brazil, Palestine, South Africa and Sweden.
