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With Diabetes, Eat Before You Exercise

With diabetes, it’s best not to skip any meals. But that’s especially important before exercise. A good rule of thumb is to eat one to three hours before exercising.

Check Your Blood Sugar Levels

If you’re taking insulin or certain diabetes medications, exercising can cause hypoglycemia, or low blood sugar levels, even up to a day later. Talk to your doctor to see if these general guidelines will work for you:

Before Exercise. Check your blood sugar and urine for ketones before you start to make sure your diabetes is stable.

If your blood sugar level is below 100 mg/dL, eat a small carbohydrate snack, such as a piece of fruit or a few graham crackers, before exercising.

If your blood sugar is 250 mg/dL or higher and you have ketones in your urine, don’t exercise. Call your doctor, no matter what type of diabetes you have. If it’s over 300 without ketones, use caution when exercising. Ketones indicate poor control of your diabetes and problems with cells that you need to help get you through your exercise.

During Exercise. Check your blood sugar every half hour if you’re exercising for more than an hour or at a higher than usual intensity, or trying a new exercise. You should stop if you feel shaky, anxious, faint, weak, or confused; are sweating more than usual; or have palpitations or a headache. Stop exercise if your blood sugar drops to 70 mg/dL or lower. A carbohydrate based food should be readily available if needed.

Recheck your blood sugar level in 15 minutes. Continue to do this until the blood sugar level comes up.

After Exercise. Check your blood glucose levels  after exercise, and again a few hours later. Check more often after a strenuous workout. If your blood sugar is low, eat a small carb snack.  Look for patterns and changes in blood glucose levels based on activity and level of exertion.  This will help you identify what changes are needed in insulin and food.

Watch Your Feet

To protect against foot injuries, especially if you have diabetic nerve damage or circulation problems, wear cotton socks and athletic shoes that fit well and have plenty of room in the toe. While running on a treadmill may seem ideal, first talk with your doctor about which exercises are discouraged and what he/she might recommend.

Inspect your feet for blisters, cuts, bumps, redness, or other sores before and after you exercise.

Wear Diabetes Identification

Carry your ID and your medical ID bracelet or necklace when you exercise. Your medical ID should include your name, address, phone number, doctor’s name and number, and type and dose of insulin or other medications you take.

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