That sucks! I'm having the exact same problem.

A little while after my shake here come the cramps. They really do hurt. I've been drinking AES from Costco. Not the best I know, but its cheap. I had been drinking it for a while no problems then I stopped, now I'm back on and I've been having stomach pains. Weird!

It doesn't seem to matter if it is pre-workout or post, morning or evening, with food or without, milk or water. it's all the same result. So bottom line I think I'm going to lay off it, and find something else. I was actually seeing pretty good gains with out it by simply eating a lot of high protein food.

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