This is a good question, because the “normal” blood sugar response to exercise varies from person to person and isn't easy to predict.
People with type 1 diabetes usually experience an increase in blood sugar after extended walking or other exercise due to higher levels of adrenaline and other hormones that trigger the liver to release sugar, and their bodies can't produce insulin in response.
By contrast, those with type 2 diabetes or prediabetes typically see their blood sugar go down slightly after physical activity. This is because exercise makes muscles more sensitive to insulin, so sugar moves out of the bloodstream and into the muscles more easily. However, sometimes people with type 2 diabetes see an increase in blood sugar following exercise because the surge in adrenaline counteracts the insulin-sensitizing effect of insulin and actually makes muscles more insulin resistant. This usually only lasts for an hour or so after physical activity.
Importantly, those on insulin or insulin-stimulating medications like glipizide or glyburide may see an initial increase in blood sugar, followed by a decrease up to 24 hours later.
Answered By dLife Expert: Franziska Spritzler, RD, CDE
Certified diabetes educator and registered dietitian living in Southern California.
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