Physical activity in post-COVID-19 condition: A cross-sectional study

BACKGROUND: Post-COVID-19 condition (PCC) is a systemic disease which can negatively influence physical activity (PA). This study aimed to examine objectively measured PA and identify its factors in adults with PCC. METHODS: Cross-sectional analysis of baseline data from a randomised-controlled trial. PA was measured with accelerometry (ActiGraph wGT3X-BT) over eight consecutive days. The primary outcome, mean 24-hour Euclidean Norm Minus One (ENMO), and the secondary outcome, the intensity gradient, were analysed using multivariable linear regression models adjusted for pre-defined covariates. RESULTS: Among 153 participants, 141 (76.6% female, age range 18-80 years) had valid PA data and were included in the analysis. Median [IQR] time spent in moderate and vigorous PA was 45.9 [32.1-61.2] and 0.16 [0.04-0.6] minutes per day, respectively. The median ENMO was 9.03 [7.2-11.2], indicating low overall PA. In regression models, chronic symptomatic disease other than PCC (β = -1.77, 95% CI = -2.93 to -0.61) and fatigue (β = 0.09, 95% CI = 0.02 to 0.16) were associated with lower mean ENMO, while higher functional capacity was associated with higher mean ENMO (β = 0.14, 95% CI = 0.05 to 0.24). For the intensity gradient, higher education and functional capacity were associated with a more favourable gradient. CONCLUSION: Presence of chronic symptomatic disease in addition to PCC, fatigue, functional capacity, and educational attainment were identified as factors of PA. These factors may be relevant for the development of therapeutic strategies to support physical activity; however, causal relationships cannot be inferred from the present study.