Diabetes in Sport

Diabetes is a disorder of blood glucose regulation, and its 2 main forms matter differently in sport.

• •Type 1 diabetes mellitus (T1DM) is autoimmune: the body makes little or no insulin, so lifelong insulin is essential and glucose must be actively managed around every session.
• •Type 2 diabetes mellitus (T2DM) involves insulin resistance, often with a relative lack of insulin, and exercise is a central part of its treatment.

Athletes with diabetes compete at the highest level, so the aim is to help them do it safely, not to hold them back. The challenge is that exercise moves blood glucose, sometimes sharply, and the direction depends on the activity. The main risks are hypoglycaemia, which exercise can mask, and, less often, high glucose with ketones.