When I first started exercising my sugars didnt drop but then as my exercise tolerance increased and my workouts became harder I noticed that not only would I drop during workouts but also about 1.5-2 hours afterwards. My endo told me I can either 1/2 my bolus rate for breakfast (I exercise after breakfast), or eat an extra 15g of carbs for a moderate workout or 30g or carbs for a hard work out without coverage. I find that if I eat the extra carbs before a work out without coverage, I tend to do ok. It is common for peoples blood sugars to drop hours after working out because you use your glucose stores in your liver. Another trick I have learned is half way through my workout, I suck on a hard candy, it seems to keep my sugar from dropping. Just keep an eye on your sugars pre, during, and post until you can figure out what your body is going to do. Good luck!