Being Active

Daily exercise is important for people with diabetes. Food, insulin, and activity affect blood glucose. They all must be balanced to keep blood glucose in target range.

depiction of the circular relation of food, activity, and insulin

Healthy Exercise Goals

  • Try to do 60 minutes of exercise every day. This can be swimming, biking, walking, or just playing outside.

  • Try to spend less than 2 hours in front of a screen every day. This includes the computer, TV, or quiet video games.

Exercise and Diabetes

  • Exercise makes your body more sensitive to insulin.

  • Exercise may cause low blood glucose:

    • During exercise

    • After exercise

    • Many hours after exercise

  • Sometimes blood glucose may be higher in the first hour after exercise.

  • Different types of exercise may cause different changes in blood glucose.

How Exercise Affects Blood Glucose

  • Check blood glucose at the following times:

    • Before starting exercise

    • Every 30 to 60 minutes during exercise

    • After exercise

    • During the night (between 2 a.m. and 3 a.m.) if exercise is late in the day

  • Keep an exercise/activity log (see Exercise and Diabetes Blood Glucose Log on page 75)


It is best to prevent low blood glucose if you know when it will happen.

Low Blood Glucose with Exercise:

Take action to prevent low blood glucose if any of the following happen:

  • Blood glucose is lower than 100 mg/dl before starting exercise.

  • You have a history of low blood glucose with exercise.

  • When starting a new type of exercise.

  • When increasing your normal amount of exercise.

  • When starting a new sports season.

How to Prevent Low Blood Glucose During Exercise

  • Check blood glucose before, during, and after exercise.

  • If blood glucose is less than 100, eat or drink a 15 gram carbohydrate and protein snack.

  • Depending on the activity and blood glucose number, you may need to eat or drink a carbohydrate and protein snack every 30 to 60 minutes.

  • Do not give insulin for exercise snacks.

  • Know YOUR common signs of low blood glucose (see page 46).

  • Do not give an insulin injection in the area you will be using during exercise

    • Example: Do not use your leg for a dinner injection if you plan to run after dinner.

Keep Yourself Safe During Exercise

  • Be prepared by keeping your testing supplies and glucagon emergency kit nearby.

  • Keep a low blood glucose treatment with you, like juice or glucose tablets.

  • Wear a diabetes medical ID like a bracelet or necklace.

  • Exercise with a buddy. Tell others about your signs of low blood glucose.

  • Do not exercise if you have ketones (small, moderate, or large).

  • Drink a lot of fluids during exercise

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