I have this not very pleasant problem with my abs. Whenever I do crunches of any kind I have horrible cramps right after the first set. It knocks me off for a good 15 - 20 minutes. Now my abs are visible all year long and my waist is pretty small. So I do not work my abs that often (mostly leg raises). However, I am trying to prepair for a show and obviously my workouts get realy brutal. I try to hit all muscle groups including abs.
Does anyone have an idea why this happenning? I do not think it depends on a change of diet because it happens every time. My diet always includes large amounts of Sodium. I am just used to it and it never causes any water retention or other problems like High Blood Pressure and such.