Impact of the COVID-19 pandemic on objectively measured physical activity and sedentary behavior among overweight young adults: A year-long longitudinal analysis.

Lawhun Costello, Victoria; Chevance, Guillaume; Wing, David; Mansour-Assi, Shadia J; Sharp, Sydney; Golaszewski, Natalie M; Young, Elizabeth A; Higgins, Michael; Ibarra, Anahi; Larsen, Britta; Godino, Job G

BACKGROUND The Coronavirus Disease 2019 (COVID-19) pandemic impacted multiple aspects of daily living, including behaviors associated with occupation, transportation, and health. It is unclear how these changes to daily living impacted physical activity and sedentary behavior. OBJECTIVE In the present study, we add to the growing body of research on the health impact of the COVID-19 pandemic by examining longitudinal changes in objectively measured daily physical activity and sedentary behavior in overweight or obese young adults participating in an ongoing weight loss trial in San Diego, California (CA). METHODS Data were collected from 315 overweight or obesity (BMI between 25.0-39.9 kg/m2) participants between the ages of 18 to 35 years old between 11/01/2019 and 10/30/2020 using the Fitbit Charge 3. After strict filtering for valid consistent wear (more than 10 hours per day for 250+ days), data from 97 participants were analyzed to detect multiple structural changes in time series of physical activity and sedentary behavior. An algorithm was designed to detect multiple structural changes that allowed for the automatic identification and dating of these changes in linear regression models with confidence intervals. The number of breakpoints in regression models were estimated with Bayesian Information Criterion (BIC) and Residual Sum of Squares (RSS), with the optimal segmentation corresponding to the lowest BIC and RSS. To quantify the changes in each outcome during the periods identified, linear mixed effects were conducted. The 97 participants included in the present analyses did not differ from the 210 participants who were excluded. RESULTS After initiation of the shelter-in-place order in CA on 03/19/2021, there were significant decreases in step counts (-2872 steps per day, 95% CI [-2734; -3010]), light physical activity (-41.9 minutes, 95% CI [39.5, 44.3]), and moderate-to-vigorous physical activity (-12.2 minutes, 95% CI [10.6, 13.8]), as well as significant increases in sedentary behavior (+52·8 minutes, 95% CI [47.0, 58.5]). Decreases were greater than the expected declines observed during winter holidays, and as of 10/30/2020, they had not returned to levels observed prior to shelter-in-place orders. CONCLUSIONS In overweight or obese young adults, physical activity decreased and sedentary behavior increased concurrent with COVID-19 mitigation strategies. Health conditions associated with sedentary lifestyle may be additional unintended costs of the COVID-19 pandemic. CLINICALTRIAL