From a personal point of view I'm recently diagnosed with T2, trying to get on top of it with diet and exercise. I'm guessing any exercise is good from a point of view of losing weight, increasing metabolism etc. So if I'm learning anything from this it's that if I'm doing 30 mins walk/run/cross train etc then often we fall into a "plod" and keep going at the same pace, bursts of high effort help to shock your body - same principle as Fartlek when running. I'm seeing this as something to add to exercise rather than replace...