High-intensity interval exercise and hypoglycaemia minimisation in adults with type 1 diabetes: A randomised cross-over trial

Aims: We aimed to examine the feasibility and safety of undertaking high-intensity interval exercise (HIIE) with evening basal insulin dose reduction on exercise-related hypoglycaemia following an afternoon bout of HIIE, compared with moderate-intensity continuous exercise and a non-exercise control day in adults with type 1 diabetes in a free-living environment. Methods: Twelve adults with type 1 diabetes participated in a randomised, crossover trial (9 female/3 male, mean age 40.4 +/- 9.9 years, duration 16.5 +/- 9.8 years, HbA1c 8.0 +/- 0.8%). Each participant undertook five conditions: a non-exercise day, and four exercise conditions on separate afternoons: a moderate-intensity continuous exercise bout; and three HIIE bouts with 10%, 20% and 30% evening basal insulin reduction. Post-exercise glucose response was measured for 24 h by continuous glucose monitoring and compared across conditions. Results: HIIE with 10%, 20% and 30% evening basal insulin dose reduction was not associated with an increase in hypoglycaemia compared with moderate-intensity continuous exercise, or the non-exercise day. There was no difference in hyperglycaemia, time-in-range or glucose variability across all exercise regimens and the non exercise day (p > .05). Conclusions: Exercise-related hypoglycaemia was not increased following afternoon HIIE when diabetes management strategies incorporating evening basal insulin dose reduction were utilised. (C) 2020 Elsevier Inc. All rights reserved.