Using sit-to-stand workstations in offices: is there a compensation effect?

PURPOSE: Sit-to-stand workstations are becoming common in modern offices and are increasingly being implemented in sedentary behavior interventions. The purpose of this study was to examine whether the introduction of such a workstation among office workers leads to reductions in sitting during working hours, and whether office workers compensate for any reduction in sitting at work by increasing sedentary time and decreasing physical activity (PA) outside work. METHODS: Office workers (n=40; 55% female) were given a WorkFit-S, sit-to-stand workstation for 3 months. Participants completed assessments at baseline (prior to workstation installation), 1-week and 6-weeks after the introduction of the workstation, and again at 3-months (post-intervention). Posture and PA were assessed using the activPAL inclinometer and ActiGraph GT3X+ accelerometer, which participants wore for 7-days during each measurement phase. RESULTS: Compared to baseline, the proportion of time spent sitting significantly decreased (75±13% versus 52±16 - 56±13%), and time spent standing and in light activity significantly increased (standing: 19±12% versus 32±12 - 37±15%, light PA: 14±4% versus 16±5%) during working hours at all follow-up assessments. However, compared to baseline, the proportion of time spent sitting significantly increased (60±11% versus 66±12 - 68±12%) and light activity significantly decreased (21±5% versus 19±5%) during non-working hours across the follow-up measurements. No differences were seen in moderate-to-vigorous activity during non-working hours throughout the study. CONCLUSION: The findings suggest that introducing a sit-to-stand workstation can significantly reduce sedentary time and increase light activity levels during working hours. However, these changes were compensated for by reducing activity and increasing sitting outside of working hours. An intervention of a sit-to-stand workstation should be accompanied by an intervention outside of working hours to limit behavior compensation.