Raul Rodrigo wrote:
I am pretty small myself and after ten years of practice, only two people, my teacher and his teacher, have ever been able to make me tap on a yonkyo. Its just the way my forearms are, and I'm not the only one in my dojo. I know of at least five of us, all under 5'5", are more or less immune to yonkyo. So the yonkyo has to be structurally correct to pressure the shoulder as well as the inside of the forearm; you can't rely on pain compliance. As my shihan once said: "Ah, he feels no pain? Okay, we break the arm."
1) I'm not a doctor, but maybe a physician could tell us whether the nerve pinch in yonkyo would be easier with a thick or thin forearm (or it doesn't make a difference?). I also also agree that the lock is more important than the pain - as I said in this other thread
2) I'm going off the track, but I was wondering how many 'yonkyo' nerve points are there? I've only experienced 3:-
i) on the inner wrist
ii) on the outer wrist
iii) near the ankles