If you take insulin or a sulfonylurea to manage your blood glucose levels, you are at increased risk of having hypoglycemia (low blood glucose) when you engage in extra exercise. And in fact, some people with diabetes limit their exercise because of this concern.
You can enjoy physical activities and maintain stable blood glucose levels if you plan wisely.
Managing diabetes requires a balance of carbohydrate intake, medications, and activity. Generally, activity lowers blood glucose levels because the working muscles use glucose for energy. It then follows that if activity lowers blood glucose levels, you will have to raise your carbohydrate intake or decrease your medication.
Adjusting your carb intake
The following general guidelines are for adjusting your carbohydrate intake. Consult your doctor about how to adjust your medications.
- When you begin a new exercise routine, check your blood glucose levels more often than usual so you can learn your body’s response to the length and intensity of exercise. Keep in mind that hypoglycemia can happen up to 24 hours after intense exercise.
- For every 30 minutes to 60 minutes of extra activity you plan to do beyond your normal daily activity, eat or drink an extra 15 grams of carbohydrate before you start the activity. You need to add the extra carbohydrate before exercising so that you prevent hypoglycemia; otherwise, you’ll get low and then have to treat the low blood glucose level. An example of what to add before your workout would be a granola bar, or crackers, or a small piece of fruit.
- If you are exercising to lose weight, ask your doctor about reducing the insulin or medication that is going to be active during the activity—instead of having to add food and additional calories.
- If you use an insulin pump, talk to your doctor about using a temporary basal rate before, during, and after the exercise.
- For longer periods of exercise (more than 1 hour) or an active day hiking or playing at the beach, eat protein along with your carbohydrate-containing foods. Examples would be bread and cheese or peanut butter crackers.
- Whenever you are exercising, always have a quick-acting carbohydrate with you. Easy items to put in your pocket or backpack are glucose tablets, glucose gel, or dried fruit snacks.
Being physically active is an integral part of managing diabetes, but you must always be alert to symptoms of hypoglycemia. By planning ahead, you can increase your carbohydrate intake so that you can exercise safely and enjoy being fit!