Exercise for type 1 diabetes mellitus management: General considerations and new directions

Type 1 diabetes mellitus (T1DM) is characterized by the loss of insulin secreting cells due to a directed autoimmune process, which is linked to oxidative stress and inflammation. Exercise training is known to induce several benefits by reducing inflammation and improving antioxidant defenses. In this context, exercise training may be considered as an efficient and relatively inexpensive non-pharmacological tool for diabetes treatment, added to the usual insulin administration. Unfortunately, most people with T1DM do not reach the recommended levels of physical activity due to concerns with hypoglycemic episodes. Recent data have demonstrated that exercise sessions composed by strength exercises or high-intensity interval exercise reduce the risk of hypoglycemia during and after the physical effort, when compared with continuous aerobic exercise in insulin-dependent patients. However, no studies have tested the chronic effects of this combination of protocols on health-related markers yet. Herein, we suggest a combination of hypertrophic strength exercises (3 sets at 8-RM) with a high-intensity interval protocol (10×60-s bouts at ∼90% HR_max interspersed with 60s recovery) in the same exercise session, three times per week, for T1DM patients free of micro and macrovascular complications. Our hypothesis is that this training protocol may minimize the exercise-associated rapid drop of glucose levels in T1DM, due to glucoregulatory hormones and transient reduction of insulin-mediated glucose uptake. This training is also likely to cover long-term glycaemic, bioenergetic, neuromuscular and cardiorespiratory adaptations, implicating in improved health and decreased risk of micro and macro complications.