Breaking Up Prolonged Sitting With Standing or Walking Attenuates the Postprandial Metabolic Response in Postmenopausal Women: A Randomized Acute Study

Abstract

OBJECTIVETo determine whether breaking up prolonged sitting with short bouts of standing or walking improves postprandial markers of cardiometabolic health in women at high risk of type 2 diabetes. RESEARCH DESIGN AND METHODSTwenty-two overweight/obese, dysglycemic, postmenopausal women (mean 6 SD age 66.6 6 4.7 years) each participated in two of the following treatments: prolonged, unbroken sitting (7.5 h) or prolonged sitting broken up with either standing or walking at a self-perceived light intensity (for 5 min every 30 min). Both allocation and treatment order were randomized. The incremental area under the curves (iAUCs) for glucose, insulin, nonesterified fatty acids (NEFA), and triglycerides were calculated for each treatment condition (mean 6 SEM). The following day, all participants underwent the 7.5-h sitting protocol. RESULTSCompared with a prolonged bout of sitting (iAUC 5.3 6 0.8 mmol/L · h), both standing (3.5 6 0.8 mmol/L · h) and walking (3.8 6 0.7 mmol/L · h) significantly reduced the glucose iAUC (both P < 0.05). When compared with prolonged sitting (548.2 6 71.8 mU/L · h), insulin was also reduced for both activity conditions (standing, 437.2 6 73.5 mU/L · h; walking, 347.9 6 78.7 mU/L · h; both P < 0.05). Both standing (21.0 6 0.2 mmol/L · h) and walking (20.8 6 0.2 mmol/L · h) attenuated the suppression of NEFA compared with prolonged sitting (21.5 6 0.2 mmol/L · h) (both P < 0.05). There was no significant effect on triglyceride iAUC. The effects on glucose (standing and walking) and insulin (walking only) persisted into the following day. CONCLUSIONSBreaking up prolonged sitting with 5-min bouts of standing or walking at a selfperceived light intensity reduced postprandial glucose, insulin, and NEFA responses in women at high risk of type 2 diabetes. This simple, behavioral approach could inform future public health interventions aimed at improving the metabolic profile of postmenopausal, dysglycemic women.

Breaking sitting with light activities vs structured exercise: a randomised crossover study demonstrating benefits for glycaemic control and insulin sensitivity in type 2 diabetes

“…The outcome of the present study fits the emerging picture that breaking up sedentary behaviour by light-intensity activities may help to improve glucose homeostasis in groups, ranging from young lean normoglycaemic individuals [16] to overweight/obese normoglycaemic [13] and dysglycaemic [14] participants. Very recently, Dempsey et al showed that breaking up sitting time with brief bouts of light-intensity walking or resistance exercise attenuates postprandial glucose and insulin responses in type 2 diabetes [12].…”

“…3c), from 211 (44) min/day in the Sitting regimen to 118 (32) (Fig. 3d) Insulin resistance (HOMA2-IR) and plasma lipids Fasting insulin levels in the Exercise regimen were similar to those in the Sitting regimen (102 [14] vs 108 [13] pmol/l, respectively; p = 0.117). In contrast, compared with Sitting, Sit Less significantly (p = 0.001) reduced fasting insulin levels to 95 [14] pmol/l).…”

“…3d) Insulin resistance (HOMA2-IR) and plasma lipids Fasting insulin levels in the Exercise regimen were similar to those in the Sitting regimen (102 [14] vs 108 [13] pmol/l, respectively; p = 0.117). In contrast, compared with Sitting, Sit Less significantly (p = 0.001) reduced fasting insulin levels to 95 [14] pmol/l). Since no significant differences were observed in mean glucose values after Sit Less as compared with Exercise ( (Table 2).…”

“…The effect size of Exercise, however, was typically intermediate compared with the effects of Sit Less and was only greater for the increases observed in fasting plasma NEFA levels vs Sitting. These results are in line with a recent study by Henson Diet during the activity regimens was assessed via diary data (from all 4 days of each regimen); activities were assessed during the last 3 days of each activity regimen using the activPAL accelerometer p values were generated using linear mixed model analyses for a overall difference and b pairwise comparisons between activity regimens EE, Energy expenditure; EXE, Exercise; SIT, Sitting; SL, Sit Less et al showing that breaking up sitting time with walking or standing increased NEFA levels in overweight/obese postmenopausal women [14]. Although the mechanism underlying the increase in NEFA concentration after Sit Less and Exercise is incompletely understood, it probably reflects a spill-over of fatty acids from increased adipose tissue lipolysis used to fuel contractile activity.…”

“…Recent evidence from observational studies shows an association between sedentary time and an increased risk of type 2 diabetes, independent of the time spent exercising [8,10]. Experimental studies under laboratory conditions suggest that regular interruption of sitting using small bouts of walking may be effective in lowering glucose and insulin levels in healthy and overweight/obese adults and in individuals with type 2 diabetes [11][12][13][14][15]. We recently showed that replacing sitting time with standing and light-intensity walking in free-living conditions was more efficient at improving insulin action than replacement with one bout of moderate-to vigorous-intensity exercise (cycling) in healthy sedentary participants [16].…”