The Effect Of Exercise On Endothelial Function And Glycemic Control In Type 2 Diabetes

Abstract

PURPOSE: Vascular endothelial dysfunction induced by hyperglycemia and elevated insulin resistance is a potent risk factor for cardiovascular disease (CVD) and likely contributes to multiple chronic disease complications associated with aging like dementia. The aim of this study was to systematically review and quantify the effects of exercise on endothelial function (EF) in type 2 diabetes (T2D). METHODS: Five electronic databases were searched (until June 2017) for studies that met the following criteria: (i) randomized controlled trials; (ii) T2D aged ≥18 years; (iii) measured EF by brachial artery flow-mediated dilation (FMD); (iv) structured and supervised exercise intervention for ≥8 weeks. RESULTS: Thirteen cohorts of eight studies (306 patients, average age 59 years) met the inclusion criteria. Exercise training significantly increased FMD (mean ES = 0.41, 95% CI = 0.21 to 0.62, P < 0.001). Low to moderate intensity subgroups and aerobic exercise (AE) subgroups significantly increased FMD more than moderate to high intensity subgroups and combined AE and resistance exercise (RE) subgroups respectively (P < 0.01, P < 0.05). Exercise training significantly decreased glycated hemoglobin (HbA1c) (mean ES = -0.40, 95% CI = -0.61 to -0.19, P < 0.001). Low to moderate intensity subgroups significantly decreased HbA1c more than moderate to high intensity subgroups (P < 0.05). CONCLUSIONS: Our results suggest that in patients with T2D, lower intensity exercise has physiological meaningful effects on EF, in support of the emerging concept that the lower efforts of exercise are not necessarily less cardioprotective than higher intensity training.