The Effect of a Physical Activity Intervention on Sedentary Behavior in Female Teachers: A Randomized, Controlled Trial

Background: Sedentary behavior, time spent sitting, is particularly worrisome because several studies indicated the health threatening outcomes of long time sitting, while few interventions aimed at reducing the sitting time. Objectives: The current study aimed at reducing the sitting time and promoting physical activity (PA) among females with sedentary behaviors through providing social support. Methods: The study was a randomized, controlled trial conducted from September to December 2014 in Jolfa, East-Azerbaijan, Iran. The study was designed to assess the effect of social support on the reduction of sitting time. A total of 230 female teachers (115 per arm) from 16 primary and secondary schools were invited to participate in the current study. The outcomes were the changing the sitting time pattern and increased PA. A self-reported questionnaire consist of 3 parts was used at baseline and 8 weeks after the intervention. Results: The mean age (standard deviation (SD) of the participants were 42 (5.4) years. Participants in both intervention and control groups reported a significant increase in their PA at work that was in favor of the intervention group (at baseline: 112 versus 153 metabolic equivalent of task (MET)-minute/week; after intervention: 399 versus 154 MET-minute/week) (P < 0.05). Considerable differences between the intervention and control groups were observed in terms of siting time (at baseline: 25.8 versus 25 hour/week; after intervention: 19.3 versus 24.3 hour/week). The reduction was significantly higher in the intervention group (6 hour/week) than the control group (0.8 hour/week). Conclusions: The findings indicated that providing a social support in schools for female teachers may improve several domains of PA and aggravate mental and physical workplace-related problems.