Daijiworld Media Network - Oslo

Oslo, Mar 7: Higher cardiorespiratory fitness may significantly reduce the risk of hospitalization due to COVID-19, though it does not appear to affect the chances of contracting SARS-CoV-2, according to a large cohort study of Norwegian adults.

Researchers analysed data from 48,821 participants in the Trøndelag Health Study, linking pre-pandemic health records collected between 2017 and 2019 with national COVID-19 registries covering February 2020 to September 2022. The study assessed estimated cardiorespiratory fitness and leisure-time physical activity levels before the pandemic.

Participants were grouped into age- and sex-specific quintiles based on peak oxygen uptake levels. Physical activity was classified as inactive, insufficiently active, or sufficiently active using metabolic equivalent hours per week.

The participants had a mean age of 53.6 years, and 53.9% were women. During an average 2.6-year follow-up period, researchers recorded 5,991 SARS-CoV-2 infections and 218 COVID-19-related hospitalizations. The findings showed that neither cardiorespiratory fitness levels nor leisure-time physical activity had any significant link with the risk of infection.

However, higher fitness levels were associated with a substantially lower risk of hospitalization. Adults in the highest fitness quintile had about a 46% lower risk of COVID-19-related hospitalization compared with those in the lowest group. Similarly, individuals who were sufficiently active before the pandemic had a 40% lower risk of hospitalization than inactive individuals.

Researchers said the findings suggest that maintaining good cardiorespiratory fitness and regular physical activity could improve resilience against severe COVID-19 outcomes, even though it may not prevent infection.