Low-intensity exercise reduces the prevalence of hyperglycemia in type 2 diabetes.

INTRODUCTION:: Glycemic instability is a severely underestimated problem in type 2 diabetes treatment. Therapeutic targets should aim to reduce postprandial blood glucose excursions. Exercise prescription can effectively improve glucose homeostasis and reduce the risk of cardiovascular complications. AIM:: To assess the impact of a single, isoenergetic bout of low- and high-intensity exercise on the prevalence of hyperglycemia throughout the subsequent 24 h post-exercise period in longstanding type 2 diabetes patients. METHODS:: Nine sedentary, male type 2 diabetes patients (age: 57+/-2 y, BMI: 29.0+/-1.0 kg/m2, Wmax: 2.2+/-0.2 W/kg body weight) were selected to participate in a randomized cross-over study. Subjects performed an isoenergetic bout of endurance type exercise for 60 min at 35%Wmax (LI) or 30 min at 70%Wmax (HI) or no exercise at all (NE). Thereafter, glycemic control was assessed over the subsequent 24 h post-exercise period by continuous glucose monitoring under strict dietary standardization but otherwise free-living conditions. RESULTS:: Average 24 h glucose concentrations were reduced following the low-intensity exercise bout (7.8+/-0.9 mmol/L) when compared with the control experiment (9.4+/-0.8 mmol/L; P<0.05). The high intensity exercise bout did not significantly lower mean glucose concentrations (8.7+/-0.7 mmol/L; P=0.14). Hyperglycemia was prevalent for as much as 35+/-9% throughout the day (NE). A single bout of exercise reduced the prevalence of hyperglycemia by 50+/-4 (P<0.05) and 19+/-9% (P=0.13) in the LI and HI exercise experiment, respectively. CONCLUSION:: A single bout of low-intensity, as opposed to high-intensity, exercise substantially reduces the prevalence of hyperglycemia throughout the subsequent 24 h post-exercise period in longstanding type 2 diabetes patients.