How "low" is low?

A few ideas based on my personal experience:
drinking before running - sometimes I drink too much before I go out for a run and end up with a bad cramp, but that's not very "low";

diaphragm (sp?) - inappropriate breathing sometimes can cause some diaphragm cramps in me... again, that's just below the rib cage;

ovaries - when I had my ovarian cysts, including a major dermoid one on the left side, it started hurting badly when I was walking with certain high-heel boots and, above all, doing high-impact aerobics (didn't run in those days). I don't mean to scare you, but some sort of cyst (ovarian or elsewhere) could be a cause... That is pretty "low", i.e. a 2-3 inches above my leg crease, not very far from my hip bone...

I hope others come up with more optimistic/easy ideas...