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Exercise Safety Tips

Know how to do exercise safely when you have diabetes.

  • Check your blood sugar before and after you do exercise.
  • Do not have alcohol, caffeine, cigarettes or marijuana before you do exercise.
  • Avoid doing exercise within 2 hours after a heavy meal.
  • Do not do exercise if you are ill with a chest infection or flu. Allow yourself time to rest before re-starting your exercise routine.

How Do I Prevent Low Blood Sugar While I Do Exercise?

Doing exercise lowers your blood sugar and helps manage diabetes. While you do exercise, your muscles use the sugar in your blood. Your muscles use the sugar in your blood for many hours after you do exercise.

Check your blood sugar before and after do exercise. Do this at least for the first 5 sessions, and anytime you make a change to your exercise program. Your blood sugar tells you how your body reacts to doing exercise. 

Some diabetes medicines can cause low blood sugar (hypoglycemia). If you are on insulin or a medicine from the Secretagogue class of medicines below, take extra care.

Find out more about exercise and low blood sugar ยป

Can I Eat Before I Do Exercise?

Avoid doing exercise within 2 hours after a heavy meal. Your body needs time to digest all the food before it is ready to do exercise. What you can do is some form of light physical activity such as going for a slow walk with your dog, family or friends. Follow your usual eating and medicine schedule. Fit your exercise into your day when you are not too full from a meal.

Can I Have Caffeine, Drink Alcohol or Smoke Before I Do Exercise?

Do not have alcohol, caffeine, cigarettes or marijuana before doing exercise. 

  • Alcohol, caffeine, cigarettes and marijuana can increase your heart rate.  If your heart rate is above your target heart rate range, then doing exercise is not safe. 
  • Alcohol, caffeine, cigarettes and marijuana also make your exercise feel tougher.

Can I Do Exercise When I'm Ill?

Do not do exercise if you are ill with a chest infection or flu. If you have an infection and taking antibiotics you need to rest. Your body needs time to rest and to fight the illness. Talk to your family doctor or exercise team about when you can return to exercise.

Allow yourself the time to rest. When you are feeling better, re-start your exercise slowly over time. Restart your exercise by doing half the time and less intensity. Think about how long you stopped doing exercise. It will take the same amount of time to build back up. 

For example, if you are prescribed to walk 2 miles in 40 minutes (a 20 minute per mile pace) and you stop doing exercise for 2 weeks then:

  • Restart with 1 mile and build up slowly to 2 miles over the first week. Walk slower than your prescribed walking pace. Walk at a 22 minute per mile pace or slower. 
  • If you feel up to it, work on speeding your walking pace back to your prescribed pace during week 2.

If you have questions, talk to your exercise team for help.

You may notice a change of blood sugar while you are ill. Changing blood sugar happens when your body is fighting an illness, especially if you become dehydrated (loss of body fluids).

  • Check your blood sugar more often when you are ill. 
  • Respond and treat a low blood sugar when necessary. 
  • Do not stop taking your insulin. 
  • Ask your doctor if you need to adjust your medicines. 
Last Reviewed: 10/16/2016