Safely finishing a half marathon by an adult with type 1 diabetes using a commercially available hybrid closed‐loop system

Glycemic targets are often difficult to achieve in people with type 1 diabetes, especially during exercise. Consequently, many people with type 1 diabetes avoid sports as a result of fear of hypoglycemia. Strenuous physical activity, such as a half marathon, imposes difficulties on people with type 1 diabetes. The first commercial hybrid closed‐loop (HCL) system with the potential to facilitate better diabetes management during exercise has recently been marketed. So far, no data on HCL performance during strenuous exercise have been published. A woman with well‐controlled type 1 diabetes participated in and safely finished a half marathon while undergoing HCL therapy. HCL could safely establish glycemic control without causing either hypo‐ or relevant hyperglycemia, and without the need for rescue carbohydrates while running. In the days after the half marathon, there was no change in glycemic control compared with the period before.