Diabetes and Exercise


Exercise can make it difficult to manage blood sugars. Different types of exercise have different effects; the time and intensity of the exercise can also affect your blood sugars. There are many factors making it difficult to predict which way your blood sugar will go. And though the effects of exercise are different for each person, generally there are a few guidelines that apply.

  • Moderately paced exercise: will likely lower blood sugars

  • Short periods of intense exercise: will likely increase blood sugars

Intense exercise may result in a rise in blood sugars due to the release of adrenaline during this time. When adrenaline is released it also releases glucose which is stored in the liver, thus resulting in a rise in blood sugars. In the same way that adrenaline is released during a short period of intense exercise, adrenaline may also be released when an athlete partakes in a competition. Though the additional stress from a competition may release adrenaline and raise blood sugars, the same effect may not be seen while playing that same sport during a practice, due to reduced stress levels. While there are immediate effects that exercise has on blood sugars, there can also be a delayed effect called delayed-onset hypoglycemia. Delayed-onset hypoglycemia is when a Type 1 Diabetic's blood sugars fall 7 to 11 hours after the exercise has ended; most commonly this happens overnight. To prevent delayed-onset hypoglycemia, for those on an insulin pump, reduction of overnight basal rates may help, and for pump users as well as those on multiple daily injections, a snack before bed can help to stabilize blood sugars.