Comparing the effects of two different break strategies on occupational sedentary behavior in a real world setting: A randomized trial

UNLABELLED Developing interventions to reduce sedentary behavior in the workplace is an important public health priority. Furthermore, research is needed to determine whether different approaches to breaking up prolonged sitting during the workday are equally feasible and effective. Thus, the purpose of this study was to determine whether varying the frequency and duration of activity breaks during the workday would differentially impact sedentary behavior and health outcomes. Inactive females (N = 49) working full-time sedentary jobs were recruited for this parallel-group randomized trial. Participants were randomly assigned to take short, frequent breaks from sitting (1-2 min every half hour; SB) or longer, planned breaks from sitting (two 15-minute breaks per workday; LB) during each workday across an 8-week intervention. Sedentary time and health outcomes were assessed at baseline and post-intervention. The study ran from March 2014-June 2015. Results showed sedentary time during the workday decreased significantly in the SB group (- 35.6 min; d = - 0.75; p = 0.03), but did not change in the LB group (+ 4.5 min; d = 0.12). Participants in the SB group also demonstrated small-to-moderate declines in total cholesterol (d = - 0.33; p = 0.10), triglycerides (d = - 0.38; p = 0.06) and fasting blood glucose (d = - 0.29; p = 0.01) from pre to post-intervention. Health outcomes did not change in the LB group. This study demonstrated that taking short, frequent breaks from sitting during the workday is a feasible and effective approach for reducing sedentary time at work. These results have implications for the development of public health messages addressing sedentary behavior, and inform future interventions to reduce sedentary time in the workplace. TRIAL REGISTRATION This study is registered at www.clinicaltrials.gov: NCT02609438.