For the study, an online survey was posted and self-reported data was utilized which included age, sex, diabetes type, latest A1C, their insulin regime, use of other medication, glucose self-monitoring practices, dietary patterns, physical activity patterns, target blood glucose range during physical activity, and regimen changes for activity and treatments for exercise-related hypo or hyperglycemia.
For dietary patterns, carbohydrate intake was calculated into the following groups:
Normal (unrestricted): >200g/day Moderate: 100-200 g/day Low carbohydrate: 40-99 g/day Very low-carbohydrate: <40 g/day
The statistical analysis of the data evaluated descriptive variables. Overall, the mean and median A1c values were within recommended ranges of less than 7%. In this study, frequency and intensity of physical activity was not a predictor of A1C. With the variables evaluated, the only one that significantly predicted A1C was use of a cgm and carbohydrate intake with the best predictor for those that followed a very low carb diet.
When blood glucose is well-managed, a greater focus on lowering carbohydrate intake may improve glycemic management along with the utilization of a continuous glucose monitor.
One thing not considered in the survey is performance. A fat-adapted athlete can perform well in endurance events. But, switching to very low carb often takes a few weeks and results in flu-like symptoms making training difficult during that time. Additionally, sprinters and many team sport athletes will not perform as well on a very low carb diet. The athletes in this research, on average, were meeting clinical guidelines and maintaining an A1C below 7%. With little research done on if there is much difference between an A1C of 6.9% and 5.9% and the extra social challenges eating very low carb may cause, it’s reasonable to question if the further lowering of A1C is necessary or beneficial, especially if it will impact performance negatively.
1 Colberg, S.R.; Kannane, J.; Diawara, N. Physical Activity, Dietary Patterns, and Glycemic Management in Active Individuals with Type 1 Diabetes: An Online Survey. Int. J. Environ. Res. Public Health 2021, 18, 9332. https://doi.org/10.3390/ijerph18179332
Kathryn received her Bachelor of Science in Exercise Physiology from Ave Maria University in Florida and a Master's degree in Clinical Exercise Physiology from West Chester University in Pennsylvania. She is Certified by the American College of Sports Medicine as well as the International Sports Science Association.