Exercise and Diabetes

by Deborah L. Mullen, CSCS
NOTE: This article is due for a revision. Please check American Diabetes Recomendations before starting a program. 

Exercise has the potential to control the diabetes by nonmedical means, reduce the severity of the disease, and significantly reduce the risk of long-term complications. This this article will discuss: what is diabetes, how exercise can help, who can exercise, footcare, hypoglycemia, precautions, and recommendations on aerobic and strength training exercise.

What is diabetes

Diabetes mellitus is a condition where the body has trouble taking glucose from the blood and delivering it to the rest of the body so that it can be used as energy. This is because of a lack of, or an inability to use insulin, the hormone required to "escort" glucose from the blood to cells of the body. There are two common types of diabetes:

Insulin-dependent diabetes mellitus, also known as Type 1. People who have this cannot produce insulin and must take insulin by injection. Because the medical concerns and complications, exercise for the Type 1 diabetic should be medically supervised.

Noninsulin-dependent diabetes mellitus, or Type 2. These people are "insulin resistant", meaning that they produce insulin, but it is not effective in escorting the glucose into the cells. Eighty to ninety percent of the diabetic opulation is Type 2. A physician will prescribe oral hypoglycemic agents if blood glucose levels cannot be controlled. As a last resort, a Type 2 diabetic will be put on insulin, which is likely if they continue with poor lifestyle choices such as sedentary living, poor eating habits and weight gain. 

How exercise can help
Aerobic exercise increases insulin sensitivity and, along with proper nutrition, helps restore normal glucose metabolism by decreasing body fat. Strength training (a.k.a. resistance or weight training) also decreases body fat by raising the metabolism. It's main benefit, however, is increasing glucose uptake by the muscles and enhancing the ability to store glucose. Exercise can mean the difference between "medical management" and "lifestyle management" of Type 2 diabetes.

Who can exercise
The American Diabetes Association recommends that anyone with diabetes have a thorough medical exam to see if there are risks for coronary artery disease and that blood glucose control is adequate before starting an exercise program. The doctor will usually advise exercise if the patient has:

sm_blue_oval.gif (76 bytes) blood glucose less than 250 mg/dl.
sm_blue_oval.gif (76 bytes) no symptoms of retinopathy, (damage to the blood vessels of the eye), neuropathy (damage to the nerves and circulation to extremities), or nephropathy (kidney damage)
sm_blue_oval.gif (76 bytes) no cardiovascular problems such as angina, embolism, or aneurysm
sm_blue_oval.gif (76 bytes) no other condition that makes exercise inadvisable.

Footcare guidelines
For a person with diabetes, there is no such thing a "just a little blister". An open sore can turn into a serious infection—proper footwear is a must. Shoes should be comfortable, well-fitting and appropriate for the chosen exercise. Before putting on the shoes, check for pebbles or other small objects inside. Smooth, not nubby socks should be worn during exercise and changed after a workout. Sweaty socks increase the chance of getting athlete's foot. Feet are to be checked daily for scratches, cuts, blisters, ingrown toenails, corns, and calluses. Immediately contact a doctor for ingrown toenails, athlete's foot, and cuts or sores that are not healing.

Hypoglycemia prevention
Hypoglycemia is a major risk among Type 2 diabetics on oral medication because of insulin-like effect of exercise. The increased glucose uptake by the muscles produces low blood glucose levels which can continue for 12 - 24 hours. The warning signs for mild and moderate hypoglycemic reactions are: trembling or shakiness, rapid heart rate, palpitations, increased sweating, excessive hunger, headache, drowsiness, mental confusion, and abrupt mood changes. In the event of a hypoglycemic attack:

sm_blue_oval.gif (76 bytes) Take action even if you are not sure you have hypoglycemia--waiting can make your symptoms much worse.
sm_blue_oval.gif (76 bytes) Take a blood-glucose test to confirm the problem.
sm_blue_oval.gif (76 bytes) Eat or drink foods with sugar such as 1/2 cup of fruit juice, six lifesavers, 1 small box of raisins, or 3 glucose tablets. (this is only a sample of effective treatments). Food with fat should be avoided because it blocks the absorption of sugar into the bloodstream.
sm_blue_oval.gif (76 bytes) Take at least a 10 - 15 minute rest and retest blood-glucose level before resuming exercise. Don't exercise if it's below 100 mg/dl or you still don't feel right.
sm_blue_oval.gif (76 bytes) If you do continue to exercise, be on the lookout for any signs that the hypoglycemic reaction is not over. Take your blood-glucose level at least every 20 - 30 minutes during your workout. After your workout eat a complex carbohydrate snack (starchy food).

Insulin sensitivity can remain high for 24 - 48 hours after a person stops exercising. Late-onset hypoglycemia is is believed to be more common than hypoglycemia that occurs during or right after exercise. It is more common among new exercisers or people who exercise strenuously. You can help prevent late-onset hypoglycemia by asking your doctor about adjusting your insulin or oral medication before exercise and increasing your food intake before and after exercise. You should also monitor your blood glucose for 12 hours after long workouts (longer than 45 minutes) or when changing the intensity or duration of your exercise--even if your workout is less than 45 minutes.

Exercise guidelines for the Type 2 diabetic
Let your body get used to exercising. Start out easy and gradually increase intensity and duration. Warm up and cool down for 5 - 10 minutes each by exercising at a low intensity before and after your moderate intensity workout. Sufficient warm up and cool down will help to prevent heart problems as well as make you less susceptible to injury. Don't exercise outdoors on very hot or humid days. You can get heat exhaustion or heat stroke. In warm weather, dress in lightweight, light-colored, loose-fitting cotton clothing or special fabrics that promote heat loss. Wear a hat and apply sunscreen. To prevent dehydration, drink a cup of cold water before and after you exercise. If you exercise longer than 30 minutes or are sweating a lot, drink water during your workout. Know the warning signs of heart problems: chest, arm or jaw pain, nausea, dizziness or fainting (also signs of heat exhaustion or hypoglycemia), unusual shortness of breath during exercise, irregular pulse.

Exercise, along with good nutrition, helps decrease body fat, which helps normalize glucose metabolism. Also, exercise helps ower coronary risk factors like high blood pressure and high cholesterol.

Aerobic exercise
Since many Type 2 diabetics are sedentary and overweight, low-impact exercise such as walking or stationary cycling is recommended, along with enough exercise to promote weight management. Their goal should be to exercise five times per week, up to 40 - 60 minutes per session at a moderate intensity. This level of exercise can be reached gradually, starting as low as 10 - 20 minutes a few times a week for a person who has never exercised. Remember to increase only one factor at a time (days per week, length of session, or intensity).

Strength training
For those who have no other complications, strength training is safe and can provide many benefits. It can increase lean mass which will help in weight management, as well as increase glucose uptake by the muscles and help the body to store glucose. Strength training programs are designed around a persons needs, desires, level of conditioning and time factors.

A basic recommendation from the American College of Sports Medicine is to train a minimum of two times per week, doing 8 - 12 repetitions per set of 8 - 10 exercises targeting major muscle groups. Safety precautions must be followed for the exercising diabetic. A personal trainer can help to set up a program for the Type 2 diabetic and help them to exercise correctly. With your doctor's permission, exercise bands are a safe, simple and effective way to exercise at home.

Medication is not enough to make a diabetic feel good and live a full life. Exercise and good nutrition provide real physical payoffs--they are essential to controlling diabetes. Exercise can help prolong your life and improve the quality of your added months and years. Sticking to an exercise program can be a challenge for anyone, even with strong medical reasons to exercise.

Measuring your blood-glucose level before and after exercise can be a motivator. Diabetics who play the "numbers game" commonly see a twenty percent decrease in their blood-glucose level after exercising. It is crucial that the exercise be fun and there is some variety. Family support and exercising with someone are helpful. Order the book Diabetes: your complete exercise guide, available from Human Kinetics at 1-800-747-4457.

Find exercise band kits (a simple way to strength train) and other exercise products at Simple Fitness Solutions

Page copy protected against web site content infringement by Copyscape
Unauthorized use of this copyrighted work will be reported to Google, whose policy is to remove access to the web page containing the infringing material in accordance with the Digital Millennium Copyright Act.
reprint permission request

Simple Fitness Solutions
Copyright ©1996 - 2008 Simple Fitness Solutions.  All Rights Reserved.