The following is a summary of “Effects of a Low-Carbohydrate-High-Protein Pre-Exercise Meal in Type 1 Diabetes—a Randomized Crossover Trial,” published in the January 2024 issue of Endocrinology by Kristensen, et al.
While current guidelines focus on adjusting insulin doses and carbohydrate intake for exercise-related glucose management in individuals with insulin pump–treated type 1 diabetes, the potential impact of other macronutrients, particularly protein, remains less explored. For a study, researchers sought to investigate the metabolic, hormonal, and physiological responses to exercise in adults with insulin pump–treated type 1 diabetes after consuming either a low-carbohydrate-high-protein (LCHP) or a high-carbohydrate-low-protein (HCLP) pre-exercise meal.
Fourteen adults (11 women, 3 men) with insulin pump–treated type 1 diabetes participated in an unblinded, 2-arm, randomized, crossover study. They consumed isocaloric meals containing either LCHP (carbohydrate 21%, protein 52%, fat 27%) or HCLP (carbohydrate 52%, protein 21%, fat 27%) 90 minutes before engaging in 45 minutes of moderate-intensity cycling. Insulin bolus doses were adjusted based on meal carbohydrate content but reduced by 25%, while basal insulin rates were decreased by 35% from meal ingestion to the end of exercise.
During exercise, participants experienced a lower coefficient of variability with LCHP compared to HCLP (LCHP: 14.5 ± 5.3 vs HCLP: 24.9 ± 7.7%, P = .001). LCHP was associated with a smaller drop in plasma glucose over exercise duration compared to HCLP (LCHP: Δ−1.49 ± 1.89 vs HCLP: Δ−3.78 ± 1.95 mmol/L, P = .001). Additionally, mean insulin concentration during exercise was 30% lower with LCHP compared to HCLP (LCHP: 25.5 ± 11.0 vs HCLP: 36.5 ± 15.9 mU/L, P < .001).
Consuming an LCHP pre-exercise meal reduced plasma glucose variability around exercise and mitigated the drop in plasma glucose over the exercise period in adults with insulin pump–treated type 1 diabetes.
Reference: academic.oup.com/jcem/article/109/1/208/7226157
