Effects of a single bout of aerobic exercise on short-term low-carbohydrate/high-fat intake-induced postprandial glucose metabolism during an oral glucose tolerance test

Objective A single bout of exercise can improve acute postprandial glucose metabolism aggravated by short-term low-carbohydrate/high-fat diet (HFD). The purpose of this study was to investigate the effect of a single bout of aerobic exercise on short-term HFD-induced postprandial glucose and incretin metabolism during an oral glucose tolerance test (OGTT). Materials/Methods Eleven healthy young men (age [mean ± SE] 27 ± 1 years; body mass index, 22 ± 1 kg/m²) performed three, 3-day interventions in randomized order: (1) a normal diet (ND: ∼ 22% fat), (2) an HFD (∼ 69% fat) and (3) an HFD with a single bout of aerobic exercise (HFDEx). The exercise (50% peak oxygen consumption; ∼ 200 kcal) was performed on the third day in HFDEx. An OGTT was performed after each 3-day dietary intervention. Results The incremental area under the curve (iAUC) of plasma glucose levels during the OGTT was significantly higher in the HFD and HFDEx trials than in the ND trial (P = 0.001). In addition, the iAUC of glucagon-like peptide-1 (GLP-1) level was significantly higher in the HFD trial than in the ND and HFDEx trials (P = 0.04). The first-phase insulin secretion indexes were significantly lower in the HFD (P = 0.01 and 0.002) and HFDEx trials (P = 0.05 and 0.008) than in the ND trial. Conclusion A single bout of aerobic exercise did not improve the short-term HFD-induced aggravation of postprandial glucose and insulin metabolism during the OGTT. However, it did normalize the increased postprandial GLP-1 level induced by HFD.