Comparing The Effects Of Different Modes Of Exercise On Glucose Handling In Young Recreationally Active Men

Abstract

PURPOSE: The prevalence of type 2 diabetes (T2D) is increasing dramatically and is characterized by insulin resistance (IR). Exercise training is an effective modality to improve IR and acutely can increase post-exercise glucose handling for up to 72 hours. However, there is conflicting evidence as to which mode of exercise elicits the greatest positive effect on glucose handling. The purpose of this study was to compare the effectiveness of different modes of exercise on post-exercise glucose handling in young recreationally active men. METHODS: Twelve (age: 22±3 years) recreationally active men completed 4 separate oral glucose tolerance tests (OGTT) either at rest, or 1.5 hours after moderate-intensity continuous exercise (MICE; 30 min @ 65% VO2peak), low-load high-repetition resistance exercise circuit (LLHR; 20-25 reps/set for 3 sets at 30% 1RM) and high-intensity interval training bout (HIIE; 10x1min at 90% HRmax). Heart rate and blood lactate were taken throughout the exercise bouts. Blood was analyzed for total plasma glucose concentration (mmol/L), c-peptide concentration (ng/mL) and blood insulin concentration (μIU/mL). RESULTS: Average blood glucose concentration during the OGTT was lower following LLHR (6.386 ± 0.261mmol/L, p = 0.03) as compared with MICE (6.839 ± 0.256 mmol/L, p = 0.03) with no differences between baseline (6.625 ± 0.333 mmol/L) and HIIE (6.737 ± 0.267 mmol/L). Glucose area under the curve (AUC) was lower following LLHR (781.76 ± 36.08) as compared to MICE (842.81 ± 35.8; p = 0.033) with no difference compared to baseline glucose AUC (804.61 ± 46.7, p = 0.475). Blood c-peptide concentrations were not significantly different between baseline, MICE, HIIE or LLHR average concentrations. Similar to c-peptide there were no significant differences between blood insulin concentrations post exercise. CONCLUSION: In young, healthy men none of the exercise modes improved glucose handling as compared with baseline. However, LLHR resistance exercise did result in greater glucose clearance than MICE, suggesting that it may be a better modality to improve glucose control. Future work should examine the acute and chronic effects of LLHR resistance exercise on glucose handling in individuals with IR to determine the potential effectiveness of this exercise modality to improve insulin sensitivity.