I recently started working on my stomach muscles three weeks ago and have noticed after each session my stomach muscles cramp up. Although it's pretty uncomfortable it's not severe cramping. I'm not sure if it has to do with my water intake or frequency of exercising but I would like to eliminate cramping after doing abdominal and oblique crunches. If you've experienced the same thing what's the best way to eliminate cramping? I do stomach muscle exercises one a week and after doing some reading on bodybuilding.com I'd like to increase the frequency of these sessions. I have a feeling my muscles are weak and probably need to become stronger in order to keep from cramping up.