Anaerobic exercise can raise your blood sugars. Do you know how your blood sugars are if you DON'T exercise for three or four days? If your blood sugars are OK when you are sitting around contemplating life in Buddha-like immobility, so you know that as a "baseline", you can then start calculating how to alter your carb intake and insulin for different types of exercise. If your non-exercising blood sugars are fine, then you can head over to the Sports and Exercise threads on here for detailed advice on how to manage your new gym routine.