Breaking up prolonged sitting does not alter postprandial glycemia in young, normal-weight men and women

A randomized, controlled, cross-over study was used to investigate the effects of breaking up prolonged sitting with low intensity physical activity on postprandial blood glucose concentrations in healthy, young, normal-weight adults. 14 men (n=6) and women (n=8) were assigned to 2.5 h of prolonged sitting (CON) and 2.5 h of prolonged sitting with 2-min bouts of walking every 20 min (LIPA). After ingesting a standardized test drink, capillary blood was sampled every 10 min to establish a postprandial blood glucose profile. Based on individual glucose responses, peak blood glucose, time-to-peak glucose, and incremental area under the glucose curve (iAUC) were determined. Paired sample t-tests were used to detect differences between trials. Peak blood glucose (p=0.55) and iAUC (CON: 252 mmol·L(-1)·2.5 h(-1) [163-340]; LIPA: 214 mmol·L(-1)·2.5 h(-1) [146-282]; p=0.45) were not different between trials. Also, time-to-peak glucose was not different between LIPA and CON (p=0.37). Taking advantage of high temporal resolution blood glucose profiles, we showed that breaking up prolonged sitting with low-intensity physical activity does not alter the postprandial blood glucose response in young, healthy, normal-weight adults. Our results indicate that postprandial glycemic control is maintained during prolonged sitting in young, healthy adults.