The hypoglycemia associated autonomic failure triggered by exercise in the patients with "brittle" diabetes and the strategy for prevention.

Exercise is a fundamental component of diabetes management. However, choosing inappropriate type or timing of exercise is associated with mild or severe hypoglycemia either during exercise or several hours after exercise. Several studies have shown that impaired counterregulatory responses triggers hypoglycemia. Therefore, in this investigation, we explored the appropriate intensity and time of exercise in patients with diabetes. The mechanisms of counterregulatory responses and hypoglycemia associated autonomic failure (HAAF), as well as the strategies for preventing episodes of hypoglycemia after exercise were also investigated. In this study, we obtained the following results: 1) High intensity interval exercise is more suitable for diabetic patients. 2) Morning exercise reduces nocturnal hypoglycemia risks compared with midday, afternoon and evening exercise. 3) Hypoglycemia can be prevented by dietary approach, reduction or suspension of insulin dose, use of mini dose glucagon, caffeine, mitigation methods, prediction algorithm, autonomic feedback controlled close-loop insulin delivery, real time continuous glucose monitoring. Based on these results we concluded that exercise may cause severe hypoglycemia or induce blunted response in patients with diabetes. For Diabetes Mellitus (DM) patients, the intensity and time of exercise influence the occurrence of hypoglycemia. This review summarizes the clinical characteristics of different types of exercises and time of exercise that can be potentially used to educate and guide patients regarding the role of exercise in standard of care.