Reducing office workers' sitting time at work using sit-stand protocols: results from a pilot randomized controlled trial

Objective: To examine the effects of different sit-stand protocols on work-time sitting and physical activity (PA) of office workers. Methods: Participants (n = 26, 77% women, mean age 42) were randomly allocated to usual sitting (control) or one of three sit-stand protocols (intervention) facilitated by height-adjustable workstations for a 4-week period between June and August 2015. Sitting, standing, and stepping time were assessed by inclinometry (activPAL); leisure-time physical activity (LTPA) by self-report. One-way analysis of covariance (ANCOVA) and post-hoc (Bonferroni) tests explored between-group differences. Results: Compared with baseline, intervention groups reduced work sitting time by 113 minutes/8-hour workday (95% confidence interval [CI] [-147,-79]) and increased work standing time by 96 minutes/8-hour workday (95% CI [67,125]) without significantly impacting LTPA/sleep time. Conclusions: Sit-stand protocols facilitated by height-adjustable workstations appear to reduce office workers' sitting time without significant adverse effects on LTPA.