Abstract
PURPOSE: To examine the effect of work- and duration-matched exercise on subsequent glucose disposal in overweight males.
METHODS: Fifteen sedentary, overweight males (mean ± SD; Age: 28.2 ± 6.9 y; BMI: 29.0 ± 3.1 kg/m2) completed two trials in randomised order. During each trial, participants completed an oral glucose tolerance test (75g; OGTT) at the same time on three successive mornings. On day 2, participants completed a duration and workload matched bout of either high-intensity interval exercise (HIIE; alternating at 100% and 50% of V[Combining Dot Above]O2peak) or continuous moderate-intensity exercise (CME; 60% V[Combining Dot Above]O2peak) prior to the OGTT. Glucose area under the curve (AUC) and peak glucose differences were calculated during the oral glucose tolerance tests. Additionally, venous blood samples were collected before exercise, immediately post-exercise and one-hour post exercise for measurement of insulin, C-peptide and adiponectin.
RESULTS: There was a main effect of time on glucose AUC, indicating a reduced AUC after exercise on day 2 when compared to day 1 (3.6%; p<0.05) and day 3 (8.0%; p<0.01). Similarly, peak glucose was lowest on day 2 when compared to day 1 (10.5%; p<0.05) and day 3 (19.6%; p<0.05). Insulin concentration was higher immediately following HIIE when compared to CME (441.3 ± 69.1 vs 348.8 ± 6.0 pg/ml; p<0.05); while both insulin and C-peptide were significantly reduced at 1 hr post-exercise (insulin: 268.3 ± 39.1 pg/ml; C-peptide: 934.0 ± 83.3 pg/ml) when compared to Pre- (insulin: 359.4 ± 58.0 pg/ml; C-peptide: 1078.5 ± 108.6 pg/ml; p<0.05) and immediately post-exercise (insulin: 395.1 ± 55.1 pg/ml; C-peptide: 1224.4 ± 110.9 pg/ml; p<0.05) in adiponectin were found either within or between the two exercise conditions, suggesting the acute exercise did not induce any anti-inflammatory benefit.
CONCLUSIONS: Exercise was effective in acutely reducing glucose AUC and peak glucose, although these effects disappeared within 24 hours. There were no differences in acute glucose tolerance between the adopted exercise conditions.