Sedentary Work and Physiological Markers of Health.

The purpose of this study is to examine associations between objectively measured workplace sedentary behavior and physiological markers of health. We hypothesize that increased sedentary time and more frequent bouts of uninterrupted sitting are associated with increased hemoglobin A1c, increased blood pressure, and impaired endothelial function. Call center employees (N = 241) were enrolled from four worksites in the United States. Participants completed a survey and a physical health assessment. Sedentary behavior and sitting/standing time at work were quantified using an accelerometer. Hemoglobin A1c was measured using a finger-prick and portable analyzer. Blood pressure was measured with an automated cuff, and vascular endothelial function was assessed in a subsample of participants (n = 56) using EndoPAT. We analyzed data with two series of ordinary least squares regressions, first to examine relationships between bouts of uninterrupted sitting and physiological outcomes, and second to examine relationships between physical activity and sitting/standing time at work and physiological outcomes. The sample was primarily female, and on average was obese, prehypertensive, and prediabetic. There were no significant relationships between bouts of uninterrupted sitting or physical activity/sitting/standing time at work and physiological outcomes. In a sample that is predominantly sedentary, at risk for cardiovascular disease, and prediabetic, there are no significant associations between workplace sedentary behavior and physiological markers. The lack of associations could be related to either physiological adaptations or ceiling effects in this sample.

The active workplace study: Protocol for a randomized controlled trial with sedentary workers.

OBJECTIVES: Sedentary behavior is pervasive in the workplace and is harmful to health. Research on the effectiveness of comprehensive workplace interventions to reduce sedentary behavior and improve worker health and safety is crucial as sedentary jobs become more common. METHODS: We developed a Total Worker Health intervention targeting sedentary behavior in call centers, and are evaluating intervention effectiveness in a randomized controlled trial. Four worksites will be randomly assigned to an intervention or control condition. The intervention condition includes the provision of active workstations along with programs and procedures at environmental, organizational, and individual levels. Control worksites will receive active workstations with no additional support, following common organizational practices. RESULTS: Outcomes include objectively measured physical activity, biological markers of health, and self-report survey data at baseline, after the 6-month intervention or control period, and at a 12-month follow-up. CONCLUSIONS: The aims of the study are to determine whether a Total Worker Health intervention has stronger impacts on workplace sedentary behavior, uninterrupted bouts of sitting, and worker health and safety compared to a usual practice control condition. The study will inform future workplace sedentary behavior intervention and dissemination research, along with organizational best practices for reducing sedentary behavior in the workplace.