Type 2 Diabetes and Exercise

Exercise is very important in managing type 2 diabetes. Combining diet, exercise, and medicine (when prescribed) will help control your weight and blood sugar level.

Exercise helps control type 2 diabetes by:

• Improving your body's use of insulin.
• Burning excess body fat, helping to decrease and control weight (decreased body fat results in improved insulin sensitivity).
• Improving muscle strength.
• Increasing bone density and strength.
• Lowering blood pressure.
• Helping to protect against heart and blood vessel disease by lowering 'bad' LDL cholesterol and increasing 'good' HDL cholesterol.
• Improving blood circulation and reducing your risk of heart disease.
• Increasing energy level and enhancing work capacity.
• Reducing stress, promoting relaxation, and releasing tension and anxiety.

Assess Yourself: Is Your Type 2 Diabetes Under Control?

How Does Exercise Affect Blood Sugar Levels?

Normally, insulin is released from the pancreas when the amount of sugar (glucose) in the blood increases, such as after eating. Insulin stimulates the liver and muscles to take in excess glucose. This results in a lowering of the blood sugar level.

When exercising, the body needs extra energy or fuel (in the form of glucose) for the exercising muscles. For short bursts of exercise, such as a quick sprint to catch the bus, the muscles and the liver can release stores of glucose for fuel. With continued moderate exercising, however, your muscles take up glucose at almost 20 times the normal rate. This lowers blood sugar levels.

But intense exercise can have the opposite effect and actually increase your blood glucose levels. This is especially true for many people with diabetes. The body recognizes intense exercise as a stress and releases stress hormones that tell your body to increase available blood sugar to fuel your muscles. If this happens to you, you may need a little bit of insulin after intense workouts.

For a variety of reasons, after exercise, people with diabetes may have an increase or a decrease in their blood sugar levels.

Is Blood Sugar Ever Too High to Exercise?

Yes. In some cases, you should hold off on exercising if your blood sugar is very high.

What Types of Exercise Is Best for Diabetes?

While most any exercise is healthy for people with diabetes, let's look at some specific types of exercise and their benefits:

 Strength Training and Type 2 Diabetes

The latest findings show that exercise such as strength training has a profound impact on helping people manage their diabetes. In a recent study of Hispanic men and women, 16 weeks of strength training produced dramatic improvements in sugar control that are comparable to taking diabetes medication. Additionally, the study volunteers were stronger, gained muscle, lost body fat, had less depression, and felt much more self-confident.

For more detail, see WebMD's article Strength Training and Diabetes.

Aerobic Fitness and Type 2 Diabetes

Any activity that raises your heart rate and keeps it up for an extended period of time will improve your aerobic fitness. Aerobic exercise helps decrease the risk of type 2 diabetes and helps those with diabetes to better manage their blood sugar levels. Besides the health benefits, exercise is fun and boosts your mood. It's hard to feel stressed when you're walking fast on a treadmill or swimming laps in a pool.

Type 2 Diabetes and Exercise Tips

• To reduce the risk of hypoglycemia if you have diabetes, follow a regular routine of exercising, eating your meals, and taking your medicines at the same time each day.
• Prolonged or strenuous exercise can cause your body to produce adrenaline and other hormones that can counteract the effects of insulin and cause your blood sugar to rise. If you are participating in strenuous exercise (exercising at your maximum capacity) or prolonged exercise (lasting for several hours or more), your insulin and/or oral diabetic medicine may need to be changed. Talk to your health care provider about how to adjust your medicine.
• Be careful exercising when your medicine is reaching its peak effect.
• Depending on the time of exercise, reducing your dose of either long-acting insulin or short-acting insulin will be necessary. Your doctor can recommend how to make this adjustment.
• Exercise with someone who knows you have diabetes and knows what to do if you have a low blood-sugar reaction.
• Wear a medical identification tag (for example, MedicAlert) or carry an identification card that states you have diabetes.

More Diabetes-Specific Exercise Tips

The American Diabetes Association offers these basic exercise guidelines for those with diabetes:

• Discuss with your doctor what types of exercise might be appropriate for you. Complications of diabetes such as severe eye disease and nerve damage may make some forms of exercise dangerous for you. Your doctor may also schedule a test to see how your heart responds to exercise.
• Do not exercise if your blood sugar is greater than 250 mg/dL (milligrams per deciliter) and your ketones positive. This is an indication that you already may have a lack of insulin and exercise will only cause a greater rise in your blood sugar. Hydrate yourself and adjust your insulin as necessary, contact your health care provider.
• Use caution when exercising if your blood sugar is greater than 300 mg/dL without evidence of ketones, exercise may help decrease your sugars, but it's possible they will increase instead. Hydrate well prior to and after exercise and keep track of your sugars and ketones.
• Learn the effects of various types of exercise on your blood sugar.
• Have carbohydrate-based foods available for exercise and for the period following exercise. Add carbohydrates to your meals if you plan on doing exercise, adjust your insulin dose appropriately in anticipation of exercise.

General Exercise Guidelines and Precautions

• If you have diabetes, check with your health care provider before you begin a an exercise program. Tell your doctor what kind of exercise you want to do so adjustments can be made to your medicine schedule or meal plan, if necessary.
• Start slowly and gradually increase your endurance.
• Choose an activity that you enjoy. You'll be more likely to stick with a program if you enjoy the activity. Make exercise a lifetime commitment.
• Consider a water exercise program. Some other exercise options include walking, riding a stationary bicycle, swimming, or muscle stretching.
• Exercise at least three to four times per week for 20 to 40 minutes each session. Ideally, you should exercise every day. A good exercise program should include a 5- to 10-minute warm-up and at least 15 to 30 minutes of continuous aerobic exercise (such as walking or biking) or muscle stretching exercises, followed by a 5-minute cool down.
• Wear good shoes and practice proper foot care.
• Drink water before, during, and after exercise to prevent dehydration.
• Do not ignore pain -- discontinue any exercise that causes unexpected pain. If you continue to perform the activity while you are in pain, you may cause unnecessary stress or damage to your joints.

Should I Stop Exercising When I Reach My Ideal Weight?

Exercise is a lifetime commitment. Regardless of your weight, you should exercise at least three to four times per week for 20 to 40 minutes each session. Ideally, you should exercise every day to help manage your type 2 diabetes long-term.

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