m not a medical professional, just the parent of a kid with diabetes. Absolutely,
exercise makes a difference.
Exercise causes the release of adrenaline in the body, and that causes your muscles to absorb the glucose from your blood stream without the need for insulin. The more exercise you get, the lower your scores, and the lower your insulin needs. Exercise also makes you feel better in general, and the better you feel, the less stress you have, and the lower your scores become as well.