I've had the same problem with exercise in general. For a while I was working out a lot (although not much ab- always aggrevates my tummy). I had to stop because of an unrelated surgery and when I tried to work out again my stomach went nuts even just doing cardio. Might be related or just a fluke, I'm not sure but I feel your pain.
-------------------- Courtney (IBS-D)
"Do your part to live in peace with everyone, as much as possible." Romans 12:18