The Assessment of Muscle Strength and Cardiorespiratory Parameters Using Simple Tests in Older Adults With Recovery From Mild COVID-19.

Objective: To evaluate muscle strength and cardiorespiratory parameters, this study uses simple tests in older adults, including those who have and have not recovered from mild coronavirus disease 2019 (COVID-19).

Methods: Eighty older adults (age≥60 years old) were divided into two groups: those without previous COVID-19 (control group, n=40) and those with recovery from mild COVID-19 (recovered group, n=40). Muscle strength was assessed using a handgrip strength test and the sit-to-stand test (STS10). Cardiorespiratory parameters were evaluated with a 1-minute sitto- stand (1-min STS) test and a 6-minute walk test (6MWT).

Results: Both groups had normal values for body mass index, blood pressure, heart rate, and pulse oxygen saturation. The recovered group showed significant differences in handgrip strength test (24.73±6.99 vs. 22.03±4.36, p=0.041) and duration for the STS10 (25.15±6.11 vs. 33.40±7.56, p<0.001) when compared to the control group. Furthermore, the recovered group had significantly decreased repetitions of a 1-min STS (31.38±4.89 vs. 21.25±3.64, p<0.001) and increased the rate of perceived exertion (RPE) (7.43±1.20 vs. 8.95±1.01, p=0.01) and leg fatigue (1.49±1.13 vs. 3.00±1.04, p=0.03) after performing a 1-min STS when compared with the control group. Moreover, the recovered group had also significantly decreased distances for the 6MWT (421.68±8.28 vs. 384.35±6.17, p<0.001) and increased the post-test RPE (7.63±1.37 vs. 12.05±1.63, p<0.001) and the post-test leg fatigue (1.71±0.88 vs. 5.28±0.91, p<0.001) compared with the control group.

Conclusion: Older adults with recovery from mild COVID-19 reported reduced muscle strength and exercise tolerance when compared with older adults without COVID-19.