Sedentary time in the workplace : a natural experiment of the transition to an activity-permissive workplace physical environment

Objective: To describe the change in objectively measured sitting, standing and stepping time for officebased workers as they transitioned from a conventional to an activity-permissive workplace physical environment. Methods: This pre-post study observed 17 office-based working adults [mean age 33 (SD 7) years] from an academic research centre as they transitioned from a conventional to a purpose-built, innovative activity-permissive workplace physical environment with flexible layouts, workspaces, and working conditions. Participants wore an activity monitor (activPAL3, PAL Technologies Limited, Glasgow, UK) for seven consecutive days at both the conventional and innovative workplaces to determine time spent sitting, standing, stepping, the number of sit to stand transitions and the length and number of sitting bouts ≥ 30 minutes. They also completed a self-reported log of workplace time and monitor wear time. Participants’ height, weight, descriptive characteristics, body composition (measured by DXA) and moderate-to-vigorous physical activity (measured by ActiGraph GT3X+; LLC, Fort Walton Beach, FL) were recorded. I standardized results to an 8-hour workday and compared outcomes between the conventional and innovative workplaces using Hodges-Lehmann median point estimate (90% CI). Results: The transition to the innovative workplace resulted in a non-significant decrease in workplace sitting time (-24 minutes/ 8-hour workday; 90% CI = -55 to 9 minutes/ 8-hour workday) and a corresponding increase in workplace standing (12 minutes/ 8- hour workday; 90% CI = -42 to 61 minutes/ 8-hour workday). There were no differences in the number of sit to stand transitions or sitting bouts ≥ 30 minutes in the workplace. Participants spent more time sitting in bouts ≥ 30 minutes at the innovative workplace (increase of 16 minutes/ 8-hour workday; 90% CI = -7 to 44 minutes/ 8-hour workday). None of these changes were statistically significant. Conclusions: This group of office workers did not significantly change their total workplace sitting time or how it was accumulated with the transition to the innovative workplace physical environment. The results of this preliminary investigation suggest that interventions include a multifaceted approach to complement physical environment changes in order to reduce prolonged sitting time.Medicine, Faculty ofMedicine, Department ofExperimental Medicine, Division ofGraduat