Breaking up of prolonged sitting over three days sustains, but does not enhance, lowering of postprandial plasma glucose and insulin in overweight and obese adults

• DOI: 10.1042/cs20140790
• Publication Date: 2015-03-03T16:54:45Z
• Authors: Robyn N. Larsen; Bronwyn A. Kingwell; Carol Robinson; Louise Hammond; Ester Cerin; Jonathan E. Shaw; Genevieve N. Healy; Marc T. Hamilton; Neville Owen; David W. Dunstan
• Keywords: Sitting

To compare the cumulative (3-day) effect of prolonged sitting on metabolic responses during a mixed meal tolerance test (MTT), with that is regularly interrupted brief bouts light-intensity walking. Overweight/obese adults (n=19) were recruited for randomized, 3-day, outpatient, cross-over trial involving: (1) 7-h days uninterrupted (SIT); and (2) activity breaks [BREAKS; 2-min treadmill walking (3.2 km/h) every 20 min (total: 17 breaks/day)]. On 1 3, participants underwent MTT (75 g carbohydrate, 50 fat) incremental area under curve (iAUC) was calculated from hourly blood samples. Generalized estimating equation (GEE) models adjusted gender, body mass index (BMI), energy intake, treatment order pre-prandial values to determine effects time, condition time × condition. The glucose iAUC 1.3 ± 0.5 1.5 mmol·h·l(-1) (mean differences S.E.M.) higher in SIT compared BREAKS 3 respectively (condition effect: P=0.001), no (P=0.48) or (P=0.8). insulin also both (day 1: ∆151 73, day 3: ∆91 73 pmol·h·l(-1), P=0.01), (P=0.52) (P=0.71). There between-treatment difference triglycerides (triacylglycerols) iAUC. significant between-condition but temporal change MTT, indicating breaking up over sustains, does not enhance, lowering postprandial insulin.