Studies already showed that the practice of physical activity (PA) is an important factor in the physical function (PF) of older adults, as well as the sedentary behavior (SB) can be negatively influence. The COVID-19 pandemic and the need for restrictive measures, the older adults had to interrupt their participation in exercise programs (EP) and consequently adopted a more restricted lifestyle.

To evaluate the relationship between SB, PA level and PF of older adults during the COVID-19 pandemic.

This is a cross-sectional study. Older adults (≥60 years), with preserved ambulation and participants in a multicomponent EP (3x50min during the week) were included. Participants were evaluated 18 months after PE interruption due to the COVID-19 pandemic. The ActivPAL3TM micro accelerometer was used to assess the time spent in SB and the PA level. The PF comprised handgrip strength, assessed by the Lafayette® hydraulic dynamometer (model J00105); lower limb strength, assessed by the 30-second sit-to-stand test (30STS); and functional mobility, assessed by the Timed Up and Go (TUG) test. Data normality was assessed using the Shapiro-Wilk test. The relationship between SB, PA level and PF data were analyzed using Pearson's correlation test. The Simple Linear Regression model was used for to verify the effect of time spent in SB and PA level in the PF variables that showed statistically significant correlations. Statistical analysis was performed using the IBM® SPSS Software (version 26.0) and a significance level of p<0.05 was adopted.

Forty-two older adults were included (73.86 ± 6.78 years, 88.10% female), with 477.03 ± 122.77 minutes per day spent in SB and the total of 7593.95 ± 3257.23 steps per day. The handgrip strength was 24.50 ± 6.41 kgf, they presented the total of 11.31 ± 2.67 repetitions in the 30STS and performed the TUG in 10.02 ± 2.27 seconds. Correlations were found between PA level and lower limb strength (r= 0.38, p<0.05), handgrip strength (r= 0.40, p<0.01) and functional mobility (r= -0.42, p<0.01). In the simple linear regression analysis, it was observed that the PA level was able to explain 15.6% of the handgrip strength (R2= 0.156, F= 7.41, p= 0.010), 14.2% of the performance in the 30STS (R2= 0.142, F= 6.60, p= 0.014) and 17.9% of the performance in the TUG test (R2= 0.179, F= 8.72, p= 0.005).

The PA level was related to the PF of older adults after the interruption of PE during the COVID-19 pandemic. In addition, the findings suggest that the PA level may be an important predictor of PF in older adults.

The findings of this study highlight the need to implement public policies that increase the practice of PA in older adults, especially in critical situations, such as the COVID-19 pandemic.