Meta-analysis of the relationship between breaks in sedentary behavior and cardiometabolic health.

OBJECTIVE The concept of "breaks" in sedentary behavior has emerged as a potential modifier of detrimental effects on adiposity caused by sedentary behavior. The existing research investigating the relationship between breaks in sedentary behavior with adiposity and cardiometabolic health in adults was systematically reviewed and quantitatively synthesized by this study. METHODS Observational and experimental studies that examined the relationships between the frequency of interruptions of sedentary behavior and markers of adiposity and cardiometabolic health in adults were identified by a systematic search of the literature. A meta-analysis was conducted by using the inverse variance method for experimental trials and a Bayesian posterior probability of existence of an association between breaks with adiposity and cardiometabolic markers for observational studies. RESULTS It was revealed by the pooled results from nine experimental studies that breaks in sedentary periods of at least light intensity may have a positive effect on glycemia but not on lipidemia for adults. It is unclear whether this effect is independent of total sitting time. However, the 10 identified observational studies showed an association with breaks, which was independent of total sedentary time, but only for obesity metrics. CONCLUSIONS The theory that interrupting bouts of sedentary behavior with light-intensity activity might help control adiposity and postprandial glycemia was supported by the evidence. Further investigations with better methods of measuring sedentary behavior patterns and improved study designs are necessary to confirm this preliminary evidence.