Abstract
Background: In contemporary society, prolonged sitting has become pervasive in our lives across many settings, including transportation, the workplace, and the home. There is a rapidly accumulating evidence that large volumes of daily sedentary time (typically in the contexts of television viewing, computer use, workplace sitting, and time spent in automobiles) are adversely associated with cardio-metabolic risk biomarkers, type 2 diabetes, some types of cancer, and premature mortality. Importantly, these detrimental associations remain even after accounting for time spent in physical activity. To inform future directions on sedentary behavior research among adults, the present paper reviews the evidence from recently-published studies, applying the behavioral epidemiology framework.
Contents: This review includes evidence on the relationships with sedentary behavior (too much sitting) with health risk indicators; self-report and device-based measurement of sedentary behaviors; the prevalence and trends for key sedentary behaviors; an ecological model and the environmental correlates of sedentary behavior; the effectiveness of interventions to reduce sedentary time; and, an overview of public health recommendations on reducing and breaking up sedentary time.
Conclusions: Future directions for sedentary behavior research are as follows: population-based prospective studies using device-based measures to better understand the impact of sedentary time on health outcomes, prospective studies to clarify the multiple levels of determinants of prolonged sitting time in different life settings, further intervention trials to reduce and break up sedentary behaviors in domestic, workplace, and transportation environments, translational research (such as mass media campaigns) to spread messages about reducing sitting time in daily life, and experimental studies to determine underlying mechanisms and dose-response relationships.