Purpose: To compare cardiometabolic responses to five consecutive days of daily postprandial exercise accumulated in three 10-min bouts or a single 30-min bout to a no-exercise control.
Methods: Ten insufficiently active adults completed three trials in a randomised order. Each trial comprised five consecutive days of 30 min of exercise either accumulated in three separate 10-min bouts (ACC) after main meals; a single 30-min bout after dinner (CONT); or a no-exercise control (NOEX). Glucose regulation was assessed from an oral glucose tolerance test. Applanation tonometry was used to assess pulse wave velocity approximately 12 h following completion of the final trial.
Results: Area under the 2-h glucose curve was similar for CONT (mean; 95% CI 917 mmol L-1 2 h-1; 815 to 1019) and ACC (931 mmol L-1 2 h-1; 794 to 1068, p = 0.671). Area under the 2-h insulin curve was greater following NOEX (70,328 pmol L-1 2 h-1; 30,962 to 109,693) than ACC (51,313 pmol L-1 2 h-1: 21,822 to 80,806, p = 0.007). Pulse wave velocity was lower for ACC (5.96 m s-1: 5.38 to 6.53) compared to CONT (6.93 m s-1: 5.92 to 7.94, p = 0.031) but not significantly lower for ACC compared to NOEX (6.52 m s-1: 5.70 to 7.34, p = 0.151).
Conclusion: Accumulating 30 min of moderate-intensity walking in three bouts throughout the day is more effective at reducing markers of cardiometabolic health risk in insufficiently active, apparently healthy adults than a single daily bout. Both accumulated and single-bout walking were equally as effective at reducing postprandial glucose concentrations compared to a no-exercise control. Therefore, accumulating exercise in short bouts after each main meal might be more advantageous for overall cardiometabolic health.
Keywords: Accumulated exercise; Glycaemic regulation; Insulin; Physical activity; Postprandial; Vascular compliance.