being able to get up from a throw without having to pick your teeth up would be my idea of a good ukemi......
I used to practice ukemi while holding a bokken or jo. It made me be very aware of my body position, the positions and movements of those around me, and made me come up in a relaxed, ready-to-fight position and, more importantly, ready-to-fight frame of mind. Of course, beginning to train like that with ukemi did have some unfortunate side-effects (remembering the words of the sensei 'did you mean to try and disembowell yourself, or was it an accident?' as I lay crumpled on the floor with the bokken sticking out from under me - ah, those were the days!
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