Prolonged sedentary time under the state of emergency during the first wave of coronavirus disease 2019: Assessing the impact of work environment in Japan

Objectives: The coronavirus disease 2019 (COVID-19) outbreak and the resulting state of emergency have restricted work environments, which may contribute to increased duration of sedentary behaviors. This study investigated the self-reported sedentary time of Japanese workers during and after the first state of emergency (April 7 to May 25, 2020) and examined differences in sedentary time after starting work from home and according to job type. Methods: We used cross-sectional data from the Japan COVID-19 and Society Internet Survey, a web-based questionnaire survey conducted from August to September 2020 (n = 11,623; age range 15-79 years; 63.6% male). Prolonged sedentary time was calculated by subtracting the sedentary time after the state of emergency (defined as the normal sedentary time) from that during the emergency, with adjustments using inverse probability weighting for being a respondent in an internet survey. Results: An increase in sedentary time of at least 2 hours was reported by 12.8% of respondents who started working from home during the state of emergency, including 9.7% of salespersons and 7.7% of desk workers. After adjusting for potential confounders, the multivariate-adjusted odds ratios (ORs) for a prolonged sedentary time ≥2 hours was significantly higher in respondents who started to work from home (OR: 2.14, 95% confidence interval: 1.78-2.57), and certain job types (desk workers; OR: 1.56, 95% CI: 1.27-1.91, salespersons; OR: 2.03, 95% CI: 1.64-2.51). Conclusions: Working from home and non-physical work environments might be important predictors of prolonged sedentary time.