A244: Effect of Different Exercise Training on Cardiac Autonomic Function in Patients with Type 2 Diabetes

Cardiac autonomic neuropathy (CAN) in patients with type 2 diabetes is usually manifested by a decrease in heart rate variability (HRV). Physical activity can improve HRV in healthy people, but the results in patients with type 2 diabetes are controversial. This study summarizes the effects of different forms of exercise on the cardiac autonomic function in patients with type 2 diabetes, to provide scientific exercise recommendations for improving the cardiac autonomic function in patients. This paper searched relevant articles in PubMed and CNKI by computer. The search terms: "exercise", "type 2 diabetes", "heart rate variability". We selected four aspects of the article, including the effect of long-term aerobic exercise, resistance exercise, aerobic combined resistance exercise, and high-intensity interval training on heart rate variability in type 2 diabetes. We excluded articles with low relevance. Finally, fifteen highly targeted articles were selected for further analysis. (1) A comprehensive assessment of cardiovascular autonomic reflex after resistance exercise in type 2 diabetic patients with CAN has found that resistance exercise has a good effect on HRV in the resting state. (2) Twelve-week aerobic exercise combined with resistance exercise has shown that exercise can effectively reduce obesity index, glycylated hemoglobin, and blood pressure, and improve insulin resistance in patients with type 2 diabetes; however, HRV significantly improved. (3) Moderate-intensity aerobic exercise for 6 months can not only increase aerobic capacity, improve glycemic control and blood lipids in type 2 diabetic patients, but also improve cardiac autonomic function and the frequency domain and time domain of HRV in CAN patients. (4) Eight-week high-intensity interval training has shown better results in cardiac autonomic regulation. The resting heart rate decreased in type 2 diabetic patients, but no significant changes were observed in HRV. Exercise improves sympathetic and parasympathetic nerve activity and the heart rate variability in patients with type 2 diabetes by inhibiting sympathetic hyperactivity and enhancing parasympathetic activity. Exercise can improve the sympathetic-vagus balance and vascular function may reduce the inflammation associated with autonomic function. For the current study, long-term moderate-intensity aerobic exercise and resistance exercise are beneficial for the improvement of cardiac autonomic function in patients with type 2 diabetes, which provides guidance for the designation of exercise prescription in diabetic patients.