| Wolf:
I'm T1 (a whole different ball game), but in my experience even 20-30 mins exercise a day has a HUGE effect on my insulin requirements. If I exercise every day (or at least 4-5 days a week) I can cut my basal insulin requirements by at least 25% and I also see an inprovement in my I:C ratio - this tells me that I am more insulin sensitive (which may be very relevant to T2's). This effect seems to be independent of the drops in BG induced immediately after exercise and in the succeeding few hours. At periods where I have increased the intensity or duration of the exercise, I haven't seen a big further improvement - I can get nearly all the benefits from as little as a 2.5 mile run or half mile swim.
This is an ongoing effect, I can afford to miss a day or two, but any longer and I have to start to take more insulin. | 
