Diabetes is a metabolic disorder in which the body either does not produce insulin at all, as with type I diabetes, or the body does not produce enough or has become resistant to insulin, as with type II diabetes. Exercise is strongly recommended as a preventative measure for type II diabetes. It helps decrease overall weight and increases insulin sensitivity, both of which are factors when developing type II diabetes. Those with type I diabetes are encouraged to exercise to maintain general fitness but not as a diabetes prevention program since type I diabetes is hereditary and not strongly associated with lifestyle factors.
Definition
According to the American Diabetic Association, type I is usually diagnosed during childhood and only effects 5 to 10 percent of those with diabetes. It is a condition you are born with where your body does not produce enough insulin to effectively take the glucose out of the blood and convert it to usable energy. Type II used to be primarily diagnosed in older adults but is now being diagnosed in children as well. You are diagnosed when your body produces insulin, but either not enough to be effective or your body has developed a resistance to the insulin. Type II diabetes often correlates with obesity and can sometimes be controlled with lifestyle modifications.
Cardiovascular Exercise
In a study published in the Journal of Endocrinology and Metabolism, researchers found that a moderate intensity cardiovascular exercise program increases insulin sensitivity in both obese and lean adolescents. They engaged in 30 minutes of moderate intensity exercise, four days per week for 12 weeks and found that insulin sensitivity increased, decreasing signs of type II diabetes. The American Council on Exercise recommends a minimum caloric expenditure of 1000 calories per week with cardiovascular exercise, with a goal of 2000 calories per week for people with type II diabetes. Ideal exercises include swimming, walking and cycling.
Strength Training
Strength training should be low intensity and high repetition. Strength training helps increase the "good" HDL cholesterol, decrease the "bad" LDL cholesterol, and chronically increases insulin sensitivity. Those with type II diabetes should aim for two days per week of strength training at 10 to 15 repetitions until muscular fatigue. Do total body exercises focusing on each major muscle group, which are the chest, back, abdominals, shoulders, legs, biceps and triceps.
Considerations
Exercise helps convert glucose in the blood to energy, so people with both types of diabetes need to be careful with timing of insulin injections and exercise. After injecting insulin, blood glucose decreases so engaging in exercise immediately after can be dangerous, since there is little blood glucose for the body to convert. Too little glucose can lead to insulin shock, with can result in coma.
Caution
Talk to a doctor before beginning exercise if you have any form of diabetes. Monitor your blood glucose before starting exercise. If your blood glucose is lower than 100 mg/dl, do not start exercise. Ingest a carbohydrate snack, wait 15 minutes and test again. If your blood glucose is higher than 250 mg/dl, do not start exercise. If you start to feel lightheaded, dizzy or lethargic during exercise, consume a fast acting glucose snack like a piece of hard candy or juice and stop exercise.
References
- American Diabetes Association: Diabetes Basics: Type I
- American Diabetes Association: Diabetes Basics: Type II
- American Council on Exercise: Exercise and Type II Diabetes
- Science Daily: Exercise Alone Shown to Improve Insulin Sensitivity in Obese Sedentary Adolescents
- "Advanced Health and Fitness Specialist Manual"; American Council on Exercise; 2009
