Like HowStuffWorks on Facebook!

How to Control Diabetes With Exercise

Avoiding Glucose Problems During Exercise

To preempt problems with you glucose levels during exercise, there are a number of things you can do -- such as:

  • Plan your activity to follow a meal so that it can help lower the increased blood glucose level that follows eating.
  • Check your blood glucose 30 minutes before and then just prior to activity. This way you can see which direction your glucose level is heading and anticipate a low in time to take preventive action.
  • If you are at risk for hypoglycemia, plan for a possible hypoglycemic episode. Carry glucose tablets with you; if symptoms of low blood glucose develop, stop the activity immediately and use the fast-acting glucose.
  • If you manage your diabetes with insulin, know the peak time of your insulin and plan your activities accordingly. Avoiding the times when your insulin is peaking and at its strongest will help you prevent hypoglycemia.
  • When injecting insulin, avoid the muscle areas that you will be using during the activity. For example, if you will be playing tennis, avoid using your racket arm and even, perhaps, your legs for your injection at the meal prior to your game. Most people find the abdomen or the buttocks work best before exercise.
  • When planning to be extremely active, test your glucose level prior to getting started. If your blood glucose is near normal but you have the potential to develop hypoglycemia, you will need to eat prior to the activity. (If you take insulin, you will either need to eat prior to the activity or lower your insulin dose.)
  • If your blood glucose before the activity is more than 250 mg/dl, check your urine for ketones. If they are present, activity will actually cause your blood glucose level to increase. An elevated glucose level and positive ketones indicate that your diabetes is uncontrolled and you need to contact your diabetes care team for advice immediately.
  • Monitor your glucose during exercise to see what effect activity has on you. Check it every half hour during exercise and again when you are finished.
  • Be sure to drink plenty of fluids. Sweating means you are losing fluids that need to be replaced. Water is usually a great choice.
  • If, during any activity, you ever experience shortness of breath, chest pain, or leg cramps that go away with rest, contact your doctor immediately. These are all possible signs of blocked arteries and require an evaluation by your doctor.
  • If you repeatedly experience episodes of hypoglycemia during and/or after increased levels of activity, you should contact your doctor and discuss the possibility of a change in your medications.

Being active needs to be fun. Otherwise, you're much less likely to stick with an active lifestyle. Choose your activities accordingly, then go out and play at least a little every day.