The emergence and rapid spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) result in a worldwide pandemic generally known as the coronavirus disease (COVID-19) pandemic. Some aspects related to a high risk of severe COVID-19 are age, physical activity (PA), and sex. Several studies have linked moderate to vigorous PA (MVPA) with a lower risk of severe infection.

Study: Association of Physical Activity With SARS-CoV-2 Infection and Severe Clinical Outcomes Amongst Patients in South Korea. Image Credit: sun okay / Shutterstock

Background

It is vital to grasp the association between MVPA and SARS-CoV-2 infection. Some studies have indicated MVPA promotes SARS-CoV-2 transmission via elevated aerosol particle emission. Other studies have indicated the health advantages linked to MVPA, similar to increased immunity, which could protect a person from severe infection. Subsequently, it is important to grasp the precise effect and mechanism of physical activity on the manifestation of COVID-19.

In regards to the Study

A recent JAMA Network Open study investigated how MVPA is related to the danger of severe COVID-19 infection. This study hypothesized that MVPA lowers the danger of severe SARS-CoV-2 infection but elevates the danger of contracting COVID-19.

Cohort data from the Korea Disease Control and Prevention Agency (KDCA) and the Korean National Health Insurance Service (NHIS) were used to evaluate the change in MVPA between consecutive biennial health screenings with COVID-19 and severe SARS-CoV-2 infection. NHIS covers almost 97% of the Korean population.

The study cohort included adults who were aged 19 years or older and took part in biennial health screenings from 2017-2018 (period 1) to 2019-2020 (period 2). A complete of two,110,268 patients fulfilled all eligibility criteria and were included on this study.

Data on the leisure time PA was collected using self-reported questionnaires during biennial health screenings. Based on the responses, PA intensity was grouped into two categories, i.e., moderate PA and vigorous PA. Moderate PA was related to exercises that cause mild shortness of breath, similar to doubles tennis and fast cycling, whereas vigorous PA was people who cause severe shortness of breath, similar to climbing and running. The authors calculated the metabolic equivalent task (MET) rating of every participant.

The association between MVPA and COVID-19 outcomes was determined based on positive SARS-CoV-2 infection. The secondary outcomes that were assessed on this study were acute clinical events of COVID-19 after hospitalization, similar to the requirement of a high-flow nasal cannula (HFNC), oxygen supply with conventional oxygen therapy (COT), admission to the intensive care unit (ICU), continuous positive airway pressure, extracorporeal membrane oxygenation, and mechanical ventilation.

Study Findings

Within the study cohort, a complete of 183,350 patients were identified to contract SARS-CoV-2 infection. The common age of those patients was 51.9 years, 51.3% were men, and 48.7% were women. The present study revealed that MVPA was positively related to contracting COVID-19 and negatively with severe COVID-19 outcomes.

Based on MVPA frequency in period 2, the share of people who were physically inactive and contracted COVID-19 was 35.8%, and 35.9% of people weren’t affected by the disease. Similar percentages of COVID-19 incidence and non-COVID-19 manifestations were observed among the many participants whose MVPA frequencies were 1 to 2 times, 3 to 4 times, and 5 or more times per week.

The effect of MVPA levels remained the identical between patients with and without SARS-CoV-2 infection between the 2 study periods. Nevertheless, COVID-19 vaccination status affected the disease state of the participants.

Unvaccinated individuals were found to be more liable to infection with increased MVPA frequency at period 2 in comparison with physically inactive patients. An elevated MVPA also revealed a nonlinear association with COVID-19. At period 1, the infection rate increased with the elevation in MVPA frequencies amongst physically lively/unvaccinated individuals. There was no significant association between increased MVPA and patients who were reinfected with COVID-19. Decreased odd ratios (ORs) were found at period 2 with increased MVPA frequency.

A discount in MVPA frequency revealed a nonlinear association with COVID-19 incidence. At period 2, the chances for COT and HFNC amongst unvaccinated patients lowered with increased MVPA frequency. As well as, the ICU admission rates were found to be insignificant in highly lively participants. The danger of COVID-19 infection decreased with the completion of the first series of COVID-19 vaccination, no matter MVPA frequencies. Although COVID-19 vaccination reversed the danger of HFNV, COT, and mechanical ventilation, it didn’t decrease ICU admission and extracorporeal membrane oxygenation.

Conclusions

The authors claim this study to be the primary to analyze the longitudinal changes in MVPA with COVID-19 outcomes, considering the vaccination status of the participants. This study provided evidence that indicated MVPA increases the danger of COVID-19 but lowers the disease severity. Nonetheless, the first outcomes were reversed with COVID-19 immunization.