Resistance Training: a Strong Case for People With Type 1 Diabetes?

Performing exercise is important for all humans, including for people living with diabetes. The World Health Organization recommends adults perform at least 150 minutes weekly of moderate to vigorous aerobic exercise because of its association with lower cardiovascular risk, longer life expectancy, and improved mental well-being (1). Additional benefits for people with diabetes include increased insulin sensitivity and weight loss, resulting in reduced insulin requirements and better glucose control, although the latter has primarily been observed in people with type 2 diabetes (2). For people with type 1 diabetes, positive effects of exercise on glycemic control are much less pronounced, showing only small reductions in glycated hemoglobin A1c (HbA1c) (3) and often restricted to young people with high HbA1c levels at baseline (4). In type 1 diabetes, glucose metabolism relies fully on exogenous insulin and insulin resistance is usually a lesser issue. More important, increased risk and fear of hypoglycemia associated with (predominantly) aerobic exercise may lead to defensive eating behavior exceeding the true need for carbohydrates, potentially counteracting any glycemic control–improving effects. A recent study showed that exercise days were associated with greater time in range and lower time above range, as measured by continuous glucose monitoring (CGM), but also increased time below range among individuals with type 1 diabetes (5). Many people with type 1 diabetes refrain from starting training or increase training workload because of fear of (nocturnal) hypoglycemia and postexercise hyperglycemia.