O Soto Otoshi

This post is primarily aimed at all who are currently teaching the jujutsu taught by Shihan Jan de Jong OAM 9th Dan. Given that I may never teach my own classes again, it is time to pass on certain insights that improves on JDJ's teachings. It is time to see further then the giant that was JDJ by standing on his shoulders.

The JDJ jujutsu grading system uniquely includes theory questions in order to examine a student's understanding of techniques. This and other similar gradings is aimed at preparing a person to become an instructor. One of the questions that JDJ would commonly ask was, 'What is the difference between o soto gari, o soto guruma, and o soto otosh?'

Firstly, a more complete question would have been, 'What are the similarities and differences' between those three techniques? The second chapter in my The Science Behind All Fighting Techniques concerns the 'core of all learning.' The core of all learning is the identification of similarities and differences. JDJ is using the core of all learning, in part, to examine the student's understanding of the techniques that they have learned.

Secondly, not one person in the Jan de Jong Self Defence School who attempted this grading and who were asked this question would have gotten the answer to this question technically right. Why? Because o soto otoshi was not taught correctly in the JDJSDS.

Wikipedia provides an adequate description of this technique for our purposes.

O soto otoshi is similar to o soto gari in that one leg of uke's is targeted, however, they are different in that with the latter the 'throwing' leg projects upward and with the former it projects downward. In wrestling it is called a lariat-leg sweep whereas in common parlance it may be termed a trip.

Another similarity and difference between o soto otoshi and o soto gari is that they are both techniques where forces are applied to cause uke to fall to the ground/mat, however, the former is a takedown whereas the latter is a throw. My biomechanically based distinction between throws and takedowns included in The Science Behind All Fighting Techniques is that with a throw, forces are applied to cause both of the opponent's feet to leave the supporting surface while with the latter they are not.

O soto otoshi is a takedown, however, it is included in Judo's nage waza, throwing techniques, category because judo does not include a takedown category in their classification of techniques; an issue explored in The Science Behind All Fighting Techniques.

The best book by far on judo 'throwing' techniques is Toshiro Daigo's Kodokan Judo Throwing Techniques. In that book, Daigo explains the basic technique and then provides various variations of that technique. One of the variations of o soto otoshi is to target both of uke's legs. This technique is similar to o soto guruma in targeting both of uke's legs but different in that tori's leg projects upward with o soto guruma but downward with the variation of o soto otoshi.

Interestingly, Daigo compares this variation of o soto otoshi to tai otoshi, body drop (although it is far more devastating taking the opponent backward rather than forward). In the judo classification, tai otoshi is classified as a te waza, hand technique, and o soto otoshi a ashi waza, leg technique, thereby illustrating the flaw in the judo classification of techniques.