  In this paper we are interested, both: at the description of Biomechanics of
the Ashi Waza techniques, with precision of few of them, members of the
Japanese, so called, Ko Waza group; and at the biomechanical analysis of the
small changes in the applicative form of them. These small changes, from the
basic movement defined by Kodokan and show in thousand books, probably born
from practical competitive situations. They are today become the usual
applicative form, not only present among the various National Federations, but
also in Japan itself among Universities dojos and the Kodokan. Among the Ko
Waza techniques, we will select for our analysis only the following: Ko Uchi
Gari , Ko Soto Gari, Ko Uchi Barai, Ko Soto Barai, Ko Soto Gake , Ko Uchi Gake
That are considered by Japanese followers different throwing techniques, as the
different names show us. But from the Biomechanical point of view all these
Kodokan throws are based on the same physical principle and practically on the
same movements.
