Walking improves cardiac function: A randomized trial on the effects of walking on left ventricular function in type 2 diabetes patients

Abstract

Background: Metabolic abnormalities in diabetic hearts are known issues, and the role of exercise in improving cardiac function has been the subject of various reports. Although it is widely believed that walking can improve cardiometabolic parameters, the specific effects of walking on cardiac function in diabetic patients remains a topic of interest. We examined the specific effects of walking on the cardiac function of diabetic patients in a randomized study. Methods:Using a random allocation sequence, 32 patients with type 2 diabetes (metformin-, insulin-, and diet-controlled) were randomized to a 12-week intervention of either walking 10 km three times/week (n=16) or standard care (control group, n= 16). We prospectively examined metabolic, anthropometric, cardiac function and cardiorespiratory fitness parameters. The groups were compared using linear regression adjusted for age. Results: Compared with that in the control group (n=16), the cardiac function (global strain) of the walking group (n=16) improved significantly after the intervention (-19.0 (+/- 3.0) vs. -20.9 (+/-2.6) (Diff -1.92 (CI-2.61-1.24) p<0.001). The global strain of the control group (n= 15) was 18.7 (+/- 3.2) vs. -18.9 (+/- 3.6) (Diff -0.19 (CI 1.00-0.63) p = 0.650). Global strain changed significantly only in the walking group: the pre/post estimated mean difference in global strain between the walking group and the control group was estimated to be -1.73 (CI-2.78, -0.69; p<0.001). Abdominal circumference (−3 cm (CI: −44.41, -1.59), p < 0.001)), heart rate at rest (−6.50 (CI: −9.69, −3.31, p < 0.001)) and body fat percentage (−2.74 (CI: −4.71, −0.76, p < 0.007)) changed significantly only in the walking group. Spiroergometric data revealed an improvement in oxygen uptake in the walking group vs the control group: abs. VO2max=0.19 (0.05, 033) (p<008) and rel. VO2max=2.43 (1.03, 3.83) (p<0.001). Conclusions:This is the first randomized intervention study of supervised walking in patients with type 2 diabetes, and results demonstrated that even moderate-intensity physical activity, such as walking, improved cardiac function, led to positive changes in body composition, reduced waist circumference, and increased oxygen uptake. Walking can be a cost-effective treatment with significant preventive and restorative benefits for cardiac function and body fat parameters in patients with type 2 diabetes.