Carbohydrate-based Strategies to Prevent Exercise-induced Hypoglycemia

Comparison of Two Carbohydrate Intake Strategies to Improve Glucose Control During Exercise in Adolescents and Adults With Type 1 Diabetes

To prevent hypoglycemia during prolonged exercise (>30 minutes), additional carbohydrate intake is frequently required. Carbohydrate intake required will vary with insulin regimens, timing and type of exercise as well as starting blood glucose level. In addition to the amount of carbohydrate ingested, the timing of carbohydrate intake could also have an impact on glucose control during exercise. Therefore, the objective of this study will be to compare the efficacy of two snacking strategies to maintain glucose levels in the target range during an exercise period in adolescents and adults with type 1 diabetes: 1) a snack containing ~0.5g of carbohydrates per kilogram of body weight - rounded to the nearest 5g - given 5 minutes before exercise; 2) a snack containing ~0.5g of carbohydrates per kilogram of body weight - rounded to the nearest 5g - distributed this way: ~40% given 5 minutes before exercise, ~30% after 20 minutes of exercise and the last ~30% after 40 minutes of exercise.

Inclusion Criteria:

1. Males and females ≥ 14 years of old.
2. Clinical diagnosis of type 1 diabetes for at least one year.
3. Last (less than 3 months) HbA1c ≤ 10%.
4. Patients using multiple daily injections with basal-bolus insulin regimen.

Exclusion Criteria:

1. Clinically significant microvascular complications: nephropathy (estimated glomerular filtration rate below 40 ml/min), neuropathy (especially diagnosed gastroparesis) or severe proliferative retinopathy as judged by the investigator.
2. Recent (< 3 months) acute macrovascular event e.g. acute coronary syndrome or cardiac surgery.
3. Abnormal blood panel and/or anemia.
4. Ongoing pregnancy.
5. Severe hypoglycemic episode within two weeks of screening.
6. Other serious medical illness likely to interfere with study participation or with the ability to complete the exercise periods by the judgment of the investigator (e.g. orthopedic limitation).
7. Treatment with CSII (Continuous Subcutaneous Insulin Infusion) "insulin pump therapy".