Same here - I tried to do some cross training in the morning and my BG shot up to 250 or more. Then I tried running, because I though surely, intense cardio wouldn't do that. Again, up to 250 in an hour. My Dr suggested that it was the liver, as previously suggested, and that I should get up earlier, eat breakfast, wait a bit, and then try exercising. Haven't tried it yet, but I hope it works.