Exercise: Making the experience work for you.

You finally made the decision — you are going to start an exercise program. Exercise can help you control your blood sugar; gain strength and flexibility; lower your LDL cholesterol (the bad cholesterol); and raise your HDL cholesterol (the good cholesterol). Here are some simple hints to make sure that you get the most from the experience.

1. First, check with your health care team. If this is your first experience with an exercise program, you will need to get a thorough medical examination. Besides a full physical, you may be scheduled for an exercise stress test to evaluate your capacity for exercise, and a dilated eye examination. These tests can identify possible complications that can affect your health. They help assure a safe experience with exercise.

2. Talk with your diabetes educator. Since glucose control is affected by activity, you may need to consider altering your diabetes medications and/or your carbohydrate intake. These changes could be needed before, during and after exercise.
  • Usually, exercise will alter your blood sugar level. The amount your blood sugar changes, however, does vary. How much it varies depend on what you do, how long you do it and how hard you work while you do it. It also depends on your blood glucose level when you start and the length of time since your last diabetes medications.

  • In general, exercise will lower your blood sugar level. In the non —diabetic individual, the body automatically lowers the circulating levels of insulin. This allows the liver to increase its output of glucose. In most cases, the glucose that is released is equal to the glucose that is utilized by the exercising muscle. As a result, the circulating level of insulin does not change. In diabetes, however, exercise may cause an increase in circulating insulin .The increased blood flow to the muscles allows more insulin to enter into the general circulation. This increase in insulin level prevents the liver from releasing enough the glucose that is required by the exercising muscle. As a result, blood sugar levels fall.

  • Sometimes, exercise may raise your blood sugar levels. This can occur due to several different reasons: the last injection of insulin was many hours before the exercise; the urine ketones are positive; or the blood sugar levels are increased before exercise (over 240 —300mg/dl). Remember, insulin is necessary to prevent the liver from releasing excessive quantities of glucose. When insulin levels are waning, or the dose of insulin is ineffective, there will be an excessive release of glucose from the liver.

3. If you exercise at differing times of the day, expect to have differing results. Therefore, you will need different guidelines to adjust both your diabetes medications and your food.

4. If you plan to join a health club, tell them that you have diabetes. According to the American for Disabilities Act, they must make reasonable accommodations for you. This includes allowing you to monitor your blood sugar levels and take appropriate interventions (taking insulin or eating a snack). It may be helpful to have your health care team provide specific guidelines for the health club to follow so they know what you need to do if your blood sugar levels fall below your target level. Don’t forget to let the instructor or your trainer know how to recognize your symptoms of hypoglycemia.

5. Be prepared. Take your meter; your insulin and syringes; a safety container to dispose used strips, lancets and syringes; and a source of carbohydrate — both fast acting and slow acting.

6. Test your blood sugar before beginning the exercise.

  • If your blood sugar is below your target or if it is below 100mg, you should postpone the exercise session. Take some food and wait until the blood sugar level has increased sufficiently to prevent a low blood sugar during exercise.

  • If your blood sugar level is over 240mg/dl, you should also consider delaying exercise. Wait until your insulin levels are sufficient enough to remedy the situation. Or, ask your diabetes team if they recommend taking a supplement of insulin to allow you to exercise sooner.

7. Begin the exercise program slowly and gradually increase the length and intensity of the exercise.

  • How hard you exercise should be calculated from the results of your exercise stress test.

  • It can also be determined by calculating your target heart rate. Subtract your age from 220 and multiply the answer by 70. This number represents the maximum heart rate that you should reach during your workout. If you are just beginning an exercise program, multiply the answer by 40 and only allow your heart rate to reach this number for 5 to 10 minutes. Then gradually increase the duration and the intensity.

  • Be sure to include stretching and warming up for at least 15 minutes before beginning your exercise routine.

  • Check your pulse before you begin to exercise, after 10 minutes of warm up and then 5 minutes into the conditioning part of your exercise program. Adjust the intensity of the exercise, to maintain you heart rate in the target range.

8. Have a ready source of carbohydrates available throughout the workout. Glucose tablets and gels as well as juice, fruit and candy are options. In general, you should plan to eat 10 to 15 grams of carbohydrate for every 30 to 60 minutes of activity. Expect that you might also need to eat some carbohydrate after the activity.

9. Monitor your blood sugar at regular intervals during the activity. It is difficult to predict exactly how much your blood sugar will change. The goal is to maintain a stable blood sugar during and after the workout.

  • If your blood sugar falls more than 40 to 60mg/dl, your system is likely to consider this as excessive lowering and respond as if it is a hypoglycemic event. It would then attempt to increase the glucose level causing it to rebound (increase) several hours after the event.

  • You should continue to regularly monitor your blood sugar level since your response to exercise will change over time. As you become more conditioned, it is likely that your blood sugar level will drop less during the workout and more likely to decrease for some hours after the workout — sometimes for as long as 24 to 48 hours.

10. Drink plenty of fluids while you are exercising. Many trainers recommend that you consume about 12 to 16 oz of fluid for every 60 minutes of strenuous activity. By the time you feel thirsty, you are already dehydrated. If a sports drink is your choice, choose one that has less than 10% glucose. Drinks with higher concentrations of glucose delay the time it takes the fluid to enter your cells. You might want to consider adding water to both juice and sports drink. This allows you to both replace fluids and replace carbohydrates.

11. Monitor your blood sugar levels for several hours after the activity. Since exercise depletes your glycogen stores, your body will often have a deficit that must be restored. It takes time for your muscles and liver to recover. This restoration, as well as enhanced insulin sensitivity, can keep you blood sugar levels low for as long as 24 to 48hours.

12. Plan to exercise 3 to 5 times a week. Research suggests that there is little conditioning achieved from exercise that is done only 1 to 2 times a week. Exercising more than 5 times a week appears to be associated with a higher risk of injury.

13. Listen to your body. Learn to recognize the symptoms of low blood sugar while you are exercising. Sweating and an increased heart rate are signs of both a healthy workout as well as a low blood sugar.

  • Also, pay attention to your body’s warning signs. If you feel pain while working out, STOP. It is no longer believed that pain results in gain. In fact, most trainers now feel that pain means no gain.

14. Bring a friend along. Studies have shown that exercising with a friend helps to enhance the likelihood that you will continue to exercise.

15. Most important, have a great time

Carolyn Robertson, RN, MSN, CS, CDE



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