Acute Effects of Resistance Exercise on Blood Glucose Levels in Postmenopausal Females with Type 1 Diabetes—A Pilot Study

Introduction and Objective: Post-menopausal females with type 1 diabetes (PFT1D) are at elevated risk of cardiovascular disease, osteoporosis, and frailty. In other populations, resistance exercise (RE) reduces these risks, but its safety for PFT1D remains unexplored. We compared the glycemic effects of high-repetition/low resistance exercise (HL), or moderate-repetition/moderate resistance exercise (MM) in PFT1D. Methods: We compared capillary blood glucose concentrations (BG) before, during, and after RE between HL (3 sets of 16 repetitions at 40% 1 repetition maximum [1RM]) and MM (3 sets of 8 repetitions at 80% 1RM) across 7 exercises targeting all major muscle groups. MM and HL were matched for total exercise volume, completed post-prandially at 4:00pm, at least 72 hours apart, in a randomized order, with similar food intake. Results: Seven PFT1D (mean±SD: age 58±6 years, diabetes duration 28±19 years, HbA1C 7.3±0.7%) completed both HL and MM. Average BG (mmol/L) was 7.1±0.9 (HL) and 7.7±1.1 (MM) before exercise, 6.8±2.1 (HL) and 7.0±0.7 (MM) after exercise, and 6.8±2.6 (HL) and 7.7±1.8 (MM) one hour after exercise. There were no differences in BG or in BG changes between HL and MM. No BG readings < 4.0mmol/L (hypoglycemic) were measured during or in the hour following exercise. According to continuous glucose monitor data, participants spent little time in hypoglycemia (BG < 3.9mmol/L) overnight (HL: 0.9%, MM: 2.5%, p=0.18) and in the 24 hours following RE (HL: 0.8%, MM: 1.1%, p=0.31). In qualitative interviews, participants indicated a strong interest in longer-term training studies, with their largest barriers to participation being time and motivation. Conclusion: BG responses to HL and MM were similar and participants maintained safe BG levels during and after both sessions. RE should cause a safe glycemic profile for PFT1D for future long-term training to test the impacts on HbA1C, bone mineral density, muscle mass, and overall long-term health. Disclosure: J.E. Logan: None. Z. Momeni: None. N.G. Boulé: Research Support; Roche Diabetes Care, Dexcom, Inc. J.E. Yardley: Research Support; Diabetes Canada, Canadian Institutes of Health Research. Speaker's Bureau; Dexcom, Inc. Funding: Alberta Diabetes Institute