Exercise Intensity And Covid-19 Infection Severity: A Cross-sectional Study

Presently, 60% of Americans have been infected by COVID-19 with >300,000 new cases each week. COVID-19 infection severity varies from no symptoms at all to severe illness and even death. Because COVID-19 is a major public health concern, it is important to identify lifestyle factors associated with the infection. A recent meta-analysis concluded that moderate to vigorous physical activity is associated with reduced risk of acquiring community spread infections and heightened immune system responses. PURPOSE: To examine the relationship between exercise intensity, COVID-19 infection, and infection severity. METHODS: College students (N = 150) owning an iPhone with the Health app were surveyed Spring of 2022. The survey instructed students to use the Health app to calculate a valid assessment of their average daily steps for the six-month period immediately preceding pandemic restrictions in the US (3/11/20). Students also recorded average daily steps for the six-month period immediately preceding the survey. Students then provided current levels of mild, mod. and vig. physical activity using a valid questionnaire; hours per week of weightlifting; whether they had ever tested positive for COVID-19; and if so, the severity of infection. Independent samples t-tests compared all study variables between students who tested positive with those who did not. Then, examining only positive cases, correlation analysis determined if any study variables were associated with severity of infection. RESULTS: There was no difference between those who tested positive for COVID-19 (n = 89) and those who did not on any exercise variable (p ≥ .275). Pre-pandemic daily steps were significantly and positively correlated with current daily steps (r = .607, p ≤ .001) as well as mild, mod. and vig. physical activity (r ≥ .215, p ≤ .045) indicating a relationship between pre-pandemic exercise behavior and current exercise behavior. Thus, all exercise variables were examined in relation to infection severity. Infection severity was significantly and negatively associated with weightlifting (r = -.224, p = .036) and trending towards a negative association with vig. physical activity (r = -.192, p = .077). CONCLUSION: Among those testing positive for COVID-19, increased vigorous exercise was associated with decreased infection severity.