Cardiorespiratory Fitness Linked to Lower COVID-19 Hospitalization Risk

Cardiorespiratory fitness is associated with a significantly lower risk of COVID-19 related hospitalization, although it does not appear to influence the likelihood of SARS-CoV-2 infection, according to a large cohort study of Norwegian adults. Maintaining a good level of fitness before the pandemic was shown to improve resilience against severe COVID-19 outcomes.

Study Details: The HUNT Study

Researchers examined data from 48,821 adults participating in the Trøndelag Health Study (the HUNT Study) in Norway. Pre-pandemic data on cardiorespiratory fitness, collected between 2017 and 2019, was linked with national COVID-19 registries covering February 2020 through September 2022. Norwegian Institute of Public Health (NIPH) maintains national COVID-19 registries.

Cardiorespiratory fitness was categorized based on peak oxygen uptake, while leisure-time physical activity was classified as inactive, insufficiently active, or sufficiently active based on metabolic equivalent hours per week.

Key Findings

• No Impact on Infection Risk: Neither cardiorespiratory fitness levels nor leisure-time physical activity categories were associated with the risk of contracting SARS-CoV-2.
• Reduced Hospitalization Risk: Higher levels of cardiorespiratory fitness were associated with a substantially lower risk of hospitalization due to COVID-19. Adults in the highest fitness quintile had a reduced risk of hospitalization compared to those in the lowest quintile (incidence rate ratio: 0.54; 95% CI: 0.34–0.86).
• Physical Activity Benefits: Adults who were sufficiently active prior to the pandemic also had a lower risk of hospitalization compared to inactive adults (incidence rate ratio: 0.60; 95% CI: 0.47–0.83).

Implications for Public Health

These findings suggest that while fitness may not prevent COVID-19 infection, it can play a crucial role in mitigating the severity of the illness. Maintaining cardiorespiratory fitness and engaging in regular physical activity could contribute to improved resilience against severe COVID-19 outcomes. This highlights the importance of prioritizing physical health, even during and after pandemics.

Study Information

The study was published in BMC Infectious Diseases in 2026. Eriksen EA et al. Cardiorespiratory fitness and physical activity and risk of SARS-CoV-2 and COVID-19 hospitalization: the HUNT study. BMC Infect Dis. 2026;DOI:10.1186/s12879-026-12684-1;26:396

As of March 7, 2026, Norway has reported 1,550,562 confirmed cases of COVID-19 and 5,732 deaths. COVID-19 pandemic in Norway