Abstract
CONTEXT: Physical activity, exercise, or both are a staple of lifestyle management approaches both for type 1 diabetes mellitus (T1DM) and type 2 diabetes (T2DM). While the current literature supports both physical activity and exercise for improving glycemic control, reducing cardiovascular risk, maintaining proper weight, and enhancing overall well-being, the optimal prescription regimen remains debated. EVIDENCE ACQUISITION: We searched PubMed and Google Scholar databases for relevant studies on exercise, insulin sensitivity, and glycemic control in people with T1DM and T2DM. EVIDENCE SYNTHESIS: In patients with T1DM, exercise generally improves cardiovascular fitness, muscle strength, and glucose levels. However, limited work has evaluated the effect of aerobic plus resistance exercise compared to either exercise type alone on glycemic outcomes. Moreover, less research has evaluated breaks in sedentary behavior with physical activity. When considering the factors that may cause hypoglycemic effects during exercise in T1DM, we found that insulin therapy, meal timing, and neuroendocrine regulation of glucose homeostasis are all important. In T2DM, physical activity is a recommended therapy independent of weight loss. Contemporary consideration of timing of exercise relative to meals and time of day, potential medication interactions, and breaks in sedentary behavior have gained recognition as potentially novel approaches that enhance glucose management. CONCLUSION: Physical activity or exercise is, overall, an effective treatment for glycemia in people with diabetes independent of weight loss. However, additional research surrounding exercise is needed to maximize the health benefit, particularly in "free-living" settings.