Exercise and You

Activity (exercise) is one of the big ways to help attain good sugar control. Exercise can lower your blood glucose, so it does take a bit of finesse to balance it out to avoid "running out of gas" during your activity. It is ideal to do regular activity five times per week for at least 30 to 60 minutes.

Activity helps you:

  • Burn blood sugar efficiently
  • Feel healthier
  • Maintain proper body weight
  • Keep your heart rate (pulse) and blood pressure in target
  • Keep your blood fat levels normal
  • Improve insulin sensitivity
  • Maintain normal blood circulation

Planning for exercise

  • Check blood sugars before, during, and after exercise.
  • You may need an extra snack before activity.
  • Have extra snacks available during exercise (see "Good foods for exercise," below).
  • Reduce the insulin dosage (with the help of your diabetes team) if you get low with activity.
  • Change the insulin injection site. It is best not to inject your insulin into a body part that is going to be used heavily during activity such as legs if you are running or arms if you are pitching a baseball game.
  • Make sure coaches and teammates are aware of your diabetes.
  • Wear medical identification.

You should NOT exercise if you have ketones present in your blood or urine, or your blood glucose is above 300. This could make your sugars go even higher and worsen the ketones. Call you health care provider for help.

Good foods for exercise

This table is for a moderate degree of exercise (for example, walking, bicycling leisurely, shooting a basketball, or mowing the lawn). If you are doing heavier exercise (for example, jogging, bicycle racing, playing in a basketball game, or digging in the garden) for the same amount of time, then you may need to add more food. Amounts vary for different people and the best way learn is to do blood sugars before and after the exercise and keep a record of the blood sugar values.

Remember to also drink water, Gatorade, or other fluids (one 8-ounce glass for A, two 8-ounce glasses for B, and three 8-once glasses for C) before or during the exercise to prevent dehydration.

Expected length of exercise Blood sugars - mg/dll Blood sugars - mmol/L Examples of foods
A. Short (15 to 30 minutes)** <80 <4.4 8 oz Gatorade or milk* or 4 to 6 oz juice*
  80 to 150 4.4 to 8.3 A fresh fruit (or any 15 grams carbohydrate*)
  >150 >8.3 None
B. Longer (30 to 120 minutes)** <80 <4.4 8 oz Gatorade or milk* or 4 oz juice plus 1/2 sandwich
  80 to 150 4.4 to 8.3 8 oz Gatorade or milk plus fresh fruit
  >150 >8.3 1/2 sandwich*
C. Longest (2 to 4 hours)** <80 <4.4 8 oz Gatorade or milk* or 4 oz juice, whole sandwich
  80 to 150 4.4 to 8.3 Fruit, whole sandwich
  >150 >8.3 Whole sandwich

*Each of these represent 14 grams of carbohydrate, which will last for about 30 minute of moderate exercise. A sandwich with meat or other protein lasts longer.

**May also need to reduce insulin dosage

This information is adapted from Understanding Diabetes by Dr. H. Peter Chase.