Children with diabetes are often sidelined during team sports and planned exercise.
Physical activity is universally recognized as an important component of a healthy lifestyle. Regular exercise improves cardiovascular outcomes, improves insulin sensitivity, and improves glycemic control in patients with diabetes. The American Academy of Pediatrics (AAP) recommends that all children, including those with diabetes, engage in 60 minutes of physical activity each day starting as young as 5 years old. Unfortunately, studies have shown that children and adolescents with diabetes are less physically active than those without diabetes.
There are several factors that may contribute to this difference in activity levels including: concerns of altered glycemic control during exercise, the need for closer monitoring, fear of being ostracized, and the fear of experiencing a hypoglycemic event. It is important that children and adolescents, especially those with diabetes mellitus, are encouraged to play sports, get regular exercise and not feel ashamed of their chronic condition. With a proper understanding of the blood glucose fluctuations that occur during exercise and a comprehensive diabetes care plan, children and adolescents can engage in sports and physical activity safely.
Understanding glucose metabolism and hormonal changes that occur during exercise is essential for the management of glycemic control in children and adolescents. The major sources of fuel for the body during exercise are carbohydrates and fat. Glucose is obtained from carbohydrates in the diet and is stored as glycogen in the liver and skeletal muscle during the resting state. As soon as exercise begins, muscle glycogenolysis serves as a primary source of glucose. Approximately 20-30 minutes into exercising, fatty acid breakdown takes over and contributes to the energy required to continue exercising. If participating in prolonged physical activity, energy is derived from free fatty acids. Exercise requires adenosine triphosphate (ATP) which is produced from various energy systems, including the glycolytic pathway, phosphagen system and aerobic mitochondrial respiration. During the first few seconds of exercise or during high intensity contractions, ATP is produced through reactions involving creatinine kinase and adenylate kinase, which eventually leads to the production of adenosine monophosphate that then promotes glycolysis. The increase in intracellular calcium and ATP promotes glucose uptake by the muscles and glycogen breakdown. Under normal conditions, insulin is produced in response to hyperglycemia and promotes the uptake of glucose by muscle and liver. Glucagon is released in response to exercise to provide energy and prevent hypoglycemia. These complex feedback interactions between glucagon, insulin and other regulatory hormones are responsible for maintaining the balance of glucose utilization and production. Children with type 1 diabetes lack the typical regulatory insulin responses to low and high blood sugars, thereby increasing the chances of the child experiencing a hypo or hyperglycemic attack. This may be due to lower glycogen stores, impaired glucagon secretion or decreased glucagon sensitivity.
Therefore, a proper care plan can optimize glycemic control before, during and after exercise.
The AAP recommends that all children, regardless of a diabetes diagnosis, undergo a pre-participation evaluation to determine if they are healthy enough to participate in physical activity. During preparation for a sporting event or exercise it is recommended that children and adolescents have a well-balanced meal with carbohydrates and protein 3-4 hours prior to exercise. Children with type 1 diabetes should have 1-2g/kg of carbohydrates 1 hour prior to physical activity. A pre-activity blood glucose check is extremely important and goal blood glucose levels should be between 90 – 250 mg/dL. If the child has blood glucose levels < 90mg/dL then a carbohydrate snack is recommended with subsequent blood glucose checks. If the child recently suffered a hypoglycemic attack (< 50mg/dL) within 24 hours of physical activity then the AAP advises against allowing the child to participate. Blood glucose should be checked during exercise with a goal range between 120 – 180 mg/dL. Maintaining adequate hydration is essential as well as replacing carbohydrates immediately following physical activity. Because of delayed hypoglycemia, blood glucose should be monitored hourly and overnight.
Children and adolescents with diabetes should be encouraged to play sports and exercise as it is proven that children who regularly exercise perform better in school, have better health outcomes and are less likely to develop chronic conditions in adulthood. The fear of hypoglycemia is a major component to the decreased number of children with diabetes participating in physical activities. However, with regular blood glucose checks, carrying emergency carbohydrates and informing coaches and instructors of their child’s condition, children with diabetes can safely participate in physical activity.
- Blood glucose should be checked before, during, and after exercise. Goal pre-activity blood glucose is 90 – 250 mg/dL for children.
- Fear of hypoglycemia is very common and often prevents children with diabetes from exercising.
- Exercise is contraindicated if the child experienced a hypoglycemic event within 24 hours or if their blood glucose is < 90 mg/dL.
Nadella S, Indyk JA, Kamboj MK. Management of diabetes mellitus in children and adolescents: engaging in physical activity. Transl Pediatr 2017;6(3):215-224. doi: 10.21037/tp.2017.05.01
Jessica Lambert; University of South Florida College of Pharmacy; Doctor of Pharmacy Candidate 2018