Effect Of Post-meal Individualized Exercise Timing On Postprandial Glycaemia In Insufficiently Active Overweight/Obese Young Males

Abstract

Postprandial glucose (PPG) elevation is a risk factor for cardiovascular disease and mortality. An acute bout of post-meal exercise effectively lowers PPG. However, the optimal timing for the initiation of post-meal exercise remains to be elucidated. Since there is great inter-individual variability in the PPG response, the optimal timing for the initiation of exercise to lower PPG should be personalized. PURPOSE: To investigate the effect of post-meal individualized exercise timing on PPG in overweight/obese young males. METHODS: Fifteen males (age: 23.2±4.0 years; body mass index: 27.0±2.4 kg·m-2) completed three 4-hour trials in a randomized order: 1) SIT: Sitting for 4 hours; 2) iP: Walking initiated at individual PPG peak time; 3) 20iP: Walking initiated at 20 minutes prior to individual PPG peak time, with each trial separated by 6-14 days. Walking was performed at 50% VO2max for 30 minutes in iP and 20iP trials. PPG peak time was determined by continuous glucose monitoring (CGM) during preliminary testing. White bread was provided to participants upon arrival and venous blood was collected every 15 minutes for the first 2 hours and every 30 minutes during the 2-4 hours after the meal to measure plasma glucose. Generalized estimating equations were used for comparison between trials. RESULTS: Compared to SIT, the 2 hour - total area under the curve (tAUC) for glucose was reduced in iP (-0.7, 95%CI [-1.7, 0.3] mmol·L -1*h, p=0.027), whereas 2 hour - incremental area under the curve (iAUC) (p=0.036 in iP and p=0.035 in 20iP) and 4 hour - iAUC (p=0.04 in iP and p=0.036 in 20iP) for glucose were reduced in both iP and 20iP respectively. Mean, coefficient of variance (CV), and peak value glucose were not affected by both walking trials (all p > 0.05 vs. SIT). CONCLUSION: Post-meal brisk walking for 30 minutes initiated at individualized PPG peak time is more effective in blunting PPG response than that initiated at 20 minutes prior to individualized peak time when compared to sitting in overweight/obese young males.