To Örebro University

Background: Physical exercise (PE) represents a challenge in achieving stable glycemic control in individuals with type 1 diabetes (T1D), especially during prolonged PE. Achieving euglycemia requires careful adjustments of carbohydrate (CHO) intake and insulin doses before, during, and after PE, by proactive use of continuous glucose monitoring (CGM).

Aim: This thesis evaluated strategies for achieving glucose control in T1D before, during, and after prolonged PE, focusing on CHO intake, insulin adjustments assisted by CGM, and education intended to improve self-management.

Methods: Four studies were conducted: (1) High CHO intake with insulin adjustments during prolonged PE; (2) CHO loading, tailored pre-race insulin dose, and high CHO intake during PE; (3) CHO replenishment after evening exercise on nocturnal glucose regulation in healthy individuals; and (4) impact of a diabetes sports camp for adults integrating education and exercise and long-term self-management.

Results: Before PE: CHO loading with basal insulin adjustment maintained stable glycemia. Tailored pre-race insulin supported euglycemia. During PE: High CHO intake (75–100 g/h) with individualized insulin strategies enabled stable glucose levels. After PE: The timing of CHO intake did not affect nocturnal glucose levels when daily energy and CHO needs were met. Self-management: The diabetes sports camp was associated with improvements in perceived diabetes self-management skills.

Conclusion: Glycemic stability in T1D before, during, and after prolonged PE is achievable through individualized CHO and insulin strategies, supported by CGM and structured education.