Exercise at a high altitude may increase the risk for hypoglycemia in individuals with T1D, according to a study published in the Journal of Clinical Endocrinology & Metabolism. Cory William Dugan, PhD-candidate, and colleagues investigated the effect of acute hypoxia (simulated high altitude) versus normoxia on blood glucose levels and carbohydrate oxidation rates during moderate-intensity exercise in individuals with T1D. During early exercise (<30 minutes), there was no fall in blood glucose levels under either condition. However, after 1 hour of exercise and during recovery, blood glucose levels were significantly lower under the hypoxic condition versus both pre-exercise levels and the normoxic condition. There was a significant rise in carbohydrate oxidation rates after exercise in both conditions that returned to baseline levels after exercise. Carbohydrate oxidation rates were higher under the hypoxic condition before, during, and after exercise. “These findings suggest that exercise performed shortly after exposure to high altitude may increase the risk of exercise-mediated hypoglycemia,” Dugan said in a statement.