It is becoming evident that in many individuals, diabetes of all types can be precipitated or exacerbated by inactivity. Exercise is a cornerstone in diabetes management and conveys many health benefits. Different forms of exercise can have varying effects on the blood sugar response, especially in individuals using insulin. Appropriate exercise for effective management of blood sugar levels and published clinical exercise recommendations for individuals with type 1 and type 2 diabetes include additional blood glucose monitoring, modified insulin doses, and supplemental carbohydrate intake. Physicians who treat exercising patients with diabetes should tailor programs to meet individual requirements.