Koshi waza
Koshi-waza is a technique, when properly executed not only creates an air of dynamic movement but also symbolizes the principles of Yin and Yang. It's a technique that requires accurate timing and spatial awareness to work efficiently. It is not the easiest technique to use immediately from an "attack" except perhaps, as a combination movement. The most common "attack" where Koshi-waza can be directly applied is Shomen -uchi where the movements of Uke and Nage are natural enough to blend for the successful execution of the technique.
So what makes Koshi-waza work? Well, there are certain fundamental principles that we have to be aware off, principles that give the technique that extra bit of polish and allows both parties the chance to experience the move. Although timing and distance are of crucial importance, they have been covered adequately in other articles on this site. The point to remember is, even though Koshi-waza is recognized as a "hip-technique", in reality it is more of a "back-carrying" movement. This point will make it easier to understand the technique. In Judo, the hips play can play an important part in performing the many variation of hip throws. Certainly, the judoka will find it easier to lift someone, however the conditions that prevail in judo do differ in Aikido, but the in essence, the principles are the same.
In Judo the contestants are required to hold and this makes it easier to draw one's "opponent" off balance and therefore control the position required to cause a lift and effect a throw. This physical contact may not be present in an Aikido "attack", yet this same link has to be present. Both arts require a committed response, however in Aikido, Nage needs to create a void without the physical contact. By instantly moving in with Atemi, Uke will respond and if the timing is right Uke will not only be drawn off balance but also be n a position to allow Nage to perform Koshi-waza.
Once Uke's balance is broken, Nage can apply the Laws of Physics and Gravity through certain mechanical movements. Nage needs to get his center point just below of Uke's (this center point is known as the "Tanden" - it is also the center of our Ki energy). Nage does this by bending his knees until he feels Uke's body across his back. Without stopping he straightens his legs and allows Uke's movement to carry him into the void that he has created .
The position of the legs will depend on the nature of the attack and the physical build of the Uke, (in Judo the feet tend to be placed between Uke's to get the maximum power in the lift and still maintain balance.). Learn to lift with the legs rather than with the back. Attempting to lift with the legs rather than with the back, which is not designed to to cope with this sort of lift and can lead to serious damage. Using the correct procedure to lift retains stability while weight, even of twice the body weight of Nage can be held for long periods. There is no reason why even the small person or someone of lighter build , should not be able to lift anybody in order to perform Koshi-waza, or any other variation of hip-throw.
The whole movement must be smooth from the start of the "attack" to Uke's completion of his fall, which must not appear hard or aggressive. Uke is projected in such a way which allows him to rise up and continue his action. unlike Judo, where Uke is thrown in such a manner so as to restrict his movements so that he can be held down on his back. The Koshi-waza's in both arts are correct, it's just the objectives are different, hence the methods are going to be different.
As already mentioned, Koshi-waza's are not that easy to perform in Aikido, except perhaps with the Shomen-uchi type "attacks". However, Koshi-waza's are absolutely perfect when used as an accompanying techniques or follow up to other Aikido movements. In performing Kakari Keiko and Taninzu waza it helps to create the unbroken flow of movement and Ki energy that is required in Aikido. Koshi-waza can be described as a "link up" technique because it can change the plane of the circular movements that is so familiar in Aikido.
The most common mistake made when practicing Koshi-waza is that it is usually practiced as a "static technique" causing one to rely on strength or Uke taking a natural "dive". No one actually learns anything and restricting oneself to this form of training deprives both uke and Nage from experiencing something quite unique. The student is advised to experiment with movement and incorporating the Koshi-waza technique into their training. Practice slowly so that every aspect of Aikido movement can be experienced. Be aware of breathing and off course timing and distance.
With the correct approach there is no reason why beginners cannot work with the experienced in learning this technique, without them feeling inadequate or suffering unnecessary anxiety. Koshi-waza's that are performed without regard to our partners can be quite painful and can devastate a person's self-confidence. For someone who has never gone over from a Koshi-waza it can be quite an unnerving experience so it is important to remember our partners limitations and initial fears. Koshi-was should be performed without the rigid awkwardness but with the creativeness expression of individual perceptiveness that the technique deserves.
"In trust is truth"
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