Exercise‐induced hypoglycaemia in type 1 diabetes

New Findings What is the topic of this review? Hypoglycaemia is a commonly cited barrier to exercise in type 1 diabetes mellitus (T1D). Knowledge of approaches to prevent or manage exercise‐induced hypoglycaemia can support patients to exercise and help clinicians to give advice. This review presents evidence‐based strategies to prevent exercise‐induced hypoglycaemia in T1D. What advances does it highlight? This review highlights approaches that can be used before, during and after exercise to mitigate the risk of hypoglycaemia. The approaches include the timing of exercise, the type of exercise, adjustments to insulin and carbohydrate, use of novel technology and education. Exercise is a key component for the management of type 1 diabetes mellitus (T1D) and is associated with reduced risk of cardiovascular disease, decreased daily insulin requirements and improved quality of life. Owing to these benefits, people with T1D are recommended to undertake regular physical activity, 150 min per week for adults and 60 min per day for children and adolescents. Despite the recommendations, many people do not meet these targets. One of the commonly cited barriers to exercise is fear of hypoglycaemia along with limited knowledge of effective preventative strategies. Hypoglycaemia can be difficult to predict, and symptoms are often masked during exercise or stress of competition. For athletes with T1D, hypoglycaemia can also limit sporting success. Hypoglycaemia before an event increases the risks of hypoglycaemia during competition and can reduce performance. To avoid hypoglycaemia, people with T1D may avoid exercise altogether or consume excessive amounts of carbohydrates, which mitigates many of the health benefits of exercise. Increased understanding of approaches to prevent or manage hypoglycaemia is therefore important to help increase levels of physical activity in people with T1D and to support athletes with T1D to compete at the highest level. This review outlines the prevalence of exercise‐related hypoglycaemia, its underlying physiology and the strategies that can be used to prevent and manage exercise‐induced hypoglycaemia in T1D. Our hope is that this knowledge will be used by people with T1D and their clinicians to find individual approaches to manage exercise‐related hypoglycaemia.