Physical activity is important for everyone, but diabetes and exercise don’t always go hand in hand. If you have diabetes, your blood sugar level can drop to dangerous levels after you exercise. However, by learning to manage your condition, you can safely exercise and keep your blood sugar regulated.
When you exercise, your body uses sugar and fat to generate energy. Sugar comes from your blood as well as your liver and muscles, where it is stored as glycogen. For example
- During the first 15 minutes of exercise. The sugar your body consumes comes from your blood or muscle glycogen.
- After 15 minutes. Fuel comes from the glycogen stored in your liver.
- After 30 minutes. Your body gets its energy from fat.
Because of this, your body depletes sugar levels and glycogen stores every time you exercise.
Everyone’s body replaces glycogen stores within a few hours, possibly up to 24 hours after vigorous activity. However, if you have diabetes and exercise, you are at a higher risk for developing hypoglycemia, or low blood sugar, while your body restores its blood sugar and glycogen stores.
Here are tips to follow when exercising with diabetes:
Consult Your Doctor
According to the Mayo Clinic, you should get 150 minutes of moderate exercise each week. However, that recommendation might not be right for you, so make sure to talk with your doctor before you start any exercise routine.
Learn more about managing diabetes.
Keep an Eye on Your Blood Sugar
When exercising, it’s important to keep tabs on your blood sugar to make sure it isn’t too high or too low. Start by checking your blood sugar 30 minutes before exercising. If it is lower than 100 mg/dL (5.6 mmol/L), it may be too low. Eat a snack with carbohydrates, such as crackers or fruit, before you start to exercise.If your blood sugar falls between 250 mg/dL (13.9 mmol/L) and 300 mg/dL (16.7 mmol/L), check your urine for ketones. If it has excess ketones, your body doesn’t have enough insulin to control your blood sugar and you could be at risk for ketoacidosis. Postpone exercise until your ketones decrease.
If your blood sugar is above 300 mg/dL (16.7 mmol/L), your glucose level is too high for exercise. Wait until it decreases to avoid dehydration and ketoacidosis.If your blood sugar is between 100 and 250 mg/dL (5.6 to 13.9 mmol/L), the Mayo clinic says you can safely exercise. You should also check your blood sugar every 30 minutes during exercise. If it falls below 70 mg/dL (3.9 mmol/L) or you feel weak, shaky or confused, stop exercising. Eat some glucose tablets or hard candy or drink a soda or juice. Check your blood sugar 15 minutes later. If it’s still low, have another serving and repeat until your blood sugar exceeds 70 mg/dL (3.9 mmol/L).Check your blood sugar immediately after exercising as well. If it is too low, eat a snack with carbohydrates or drink some fruit juice.
Time Your Workouts and Meals
When you exercise can affect how your body reacts. Limit exercise to one or two sessions a day, and avoid exercising at the peak of your insulin action. Also, be sure to finish two hours or more before bedtime. If your glucose is lower than 100 mg/dL when you’re ready for bed, double your bedtime snack. You should also avoid drinking alcohol and skipping meals and snacks before and after exercising. Diabetes and exercise can be combined safely if you learn to manage your condition. Use these tips to keep your blood sugar at a safe level during physical activity.
Advice or recommendations are for informational or educational purposes only, not a substitute for a visit or consultation with your doctor.
Consult your doctor before beginning any diet or exercise program.
Get more information about specific health terms, topics and conditions to better manage your health on bcbst.com. BlueCross BlueShield of Tennessee members can access wellness-related discounts on fitness products, gym memberships, healthy eating and more through Blue365®. BCBST members can also find tools and resources to help improve health and well-being by logging into BlueAccess and going to the Managing Your Health tab.