Competition Induced Hyperglycemia in Athletes With Type 1 Diabetes

Design and methods 12 athletes with T1D and 12 healthy athletes are included in a prospective experimental randomized, cross-over study. Athletes are provided with a Dexcom G6 CGM to measure glucose excursions before, during and after exercise and a Holter ECG-E-patch to measure HRV. Psychological stress levels are assessed from Competitive State Anxiety Inventory-2. The athletes are studied on two occasions: Day 1: 5K running competition and Day 2: 5K high intensity training session (running) in the athletes' regular training environment. Endpoints Primary endpoints: Change in plasma glucose from start of exercise to end of exercise during competition compared to training. Secondary endpoints: Hormonal response (cortisol, adrenalin, noradrenaline). Changes in heart rate and HRV before, during and after exercise. CGM-glucose and plasma glucose discrepancies.

Inclusion Criteria: * T1D and healthy athletes who are otherwise healthy * Age between 18 and 65 years * HbA1c less than 70 mmol/mol * The athletes must be engaged in competitive sports that includes running, and agree to participate in a local 5 km running competition within 3 months Exclusion Criteria: * Proliferative retinopathy * Hypoglycemia unawareness * Heart disease and other conditions which may be negatively affected by the VO2 max test and study days