Diabetes is increasing among teenagers, and can lead to serious health consequences in the short and long term if blood sugar is poorly controlled. Teenagers with either Type 1 or Type 2 diabetes can improve control with exercise. Both aerobic and resistance training lower blood sugar by sensitizing muscle cells to insulin. Combining both types of exercise provides the best results.
Exercise and Normal Blood Sugar
Your body uses blood sugar for fuel only after the sugar enters your cells. The sugar is carried through the cell's outer surface by special attachments called receptors. The receptors only work when triggered by insulin produced in your pancreas. Exercise creates more of these receptors on the cell surface, lowering blood sugar and providing working muscles with fuel.
Storing Blood Sugar
Muscles cells can store sugar, in the form of glycogen, when you are at rest. Your body uses this stored energy predominantly in the first five to ten minutes of exercise, then the muscles depend on sugar supplied by the blood. The liver also stores glycogen, in fact, your liver is a fuel tank for the body. When you exercise, signals are sent to your liver to release it's stores of sugar into the blood for use by the muscles. When the stores in the liver are gone, the liver makes sugar to release into the blood through gluconeogenesis. If you could not store energy, or create glucose through gluconeogenesis, you could not exercise more than 10 to 15 minutes without eating.
Exercise and Type 1 Diabetes
Most teenagers with high blood sugar levels have Type 1 diabetes. In this type of diabetes, your pancreas is unable to make enough insulin. With exercise, your insulin dose may decrease. Many young people are worried about an unsafe drop in their blood sugar with exercise. This can be avoided by close monitoring and advice from your doctor. If you have a blood sugar above 250, it may rise when you exercise due to low insulin levels. Without enough insulin, too much sugar is released from the liver and trapped in the blood.
Exercise and type 2 diabetes
In Type 2 diabetes, the pancreas makes insulin, but the cells don't respond. This type of diabetes is on the rise among teenagers due to less active lifestyles and high calorie foods. If you are a Type 2 diabetic struggling with your weight, both exercise and weight loss will lower blood sugar. A combination of the two, however, is the most effective for preventing serious health problems as you age.
Blood Sugar after Exercise
After exercising strenuously, your stores of glycogen are depleted. Rebuilding them may take many hours, during which time muscle and liver cells continue to take up glucose at an increased rate. If you are a diabetic with enough insulin on board, you will notice your blood sugar readings stay low during this time. Once you have repleted glycogen, the body can resume storing excess energy in fat cells.
References
- Eur J Epidemiol."Does physical activity modify the risk of obesity for type 2 diabetes: a review of epidemiological data; Qin, et al. Sept, 2009
- Diabetes/Metabolism Reviews"Therapy and Better Quality of Life: The Dichotomous Role of Exercise in Diabetes Mellitus; Kemmer et al. 1986
- Textbook of Medical Physiology Guyton, 1986
- Int J Pediatr. "Physical activity in adolescent females with type 1 diabetes; Schweiger, et al. May 2010
- ",Effects of Exercise in Diabetes Mellitus in Adults" McCulloch et al. Sept 28, 2009
- Diabetologia "Physical Exercise and Fuel Homeostasis in diabetes Mellitus" Wahren et al. 1978
