Chi and ki are obviously the same thing. However, whenever I see Japanese MAists do internal strikes, it seems like they use ki as a focus rather than using the ki for the actual strike. In Chinese MA when you do internal strikes you use the chi for the strike, or to power the strike. Is this observation correct? How do Japanese MA use ki? How do Aikido, Aikijutsu, ninjitsu, jiujitsu, and other Japanese MA differ in their uses of ki? I know enough about how Chinese styles use chi, but I've only watched Japanese MAists use ki, so I don't know much about how Japanese styles use ki.
G'day, I will try to answer this as best I know how. This topic is actually in my frequently pondered thoughts pile The Japanese use of the term Ki seems to be quite a different idea to the idea of Qi prominent in Chinese internal styles. The Chinese utilise the traditional Chinese medical view of the body and its channels and collaterals through which the Zheng Qi flows. The Japanese, however, seem less concerned with channel theory or the physiology of Qi or Ki and more concerned with the way technique is performed and the associated mindset. This is not to say the chinese systems are any less concerned with these aspects but they also seem to be more aware of the intricate details of traditional physiology. It is my opinion that the Japanese systems use the word Ki to explain subtle biomechanics. The majority of Japanese systems rely on the unidirectional application of force using the hips as the base for this application. It is for this reason that the Hara is among the only traditional medical concept prevalent in the teachings of the majority of Japanese styles. The Chinese internal systems often have specific exercises for each element of the Wu Xing or for the individual associated organ/channel systems. This is an idea not reflected in the Japanese arts to the same degree. I can think of a particular instance where a Japanese Aikido instructor named Yamada Sensei was demonstrating irimi nage and would say, in broken english, "No use power!" at which point he would bend his back and apply the technique to no avail with his arms, then he would say "use Ki!", at which point he would straighten his spine and apply the technique using his hips and send his poor litle uke upside down into the tatami. This demonstration struck me as typical of the thinking of Japanese art practitioners in relation to Ki. Another example is the overused demonstration of the unbendable arm. In this exercise the person is to attempt to use strength to make a fist and stop their arm being bent, which invariably ends up with all muscles of the arm, including the flexors (which are required to make a fist) and the arm bends with relative ease and the person ends up tired. The person is then instructed to visualise energy flowing from thier Hara and up and out thier fingertips with an open palm, face up. Now it is very difficult for the arm to be bent and the person trying to bend the arm exerts much more energy than the bend-ee. This is an example of efficient biomechanics, as the hips are engaged in the second attempt and only the extensor muscles and triceps are used to straighten the arm, thus relying on less energy and not opposing your own movement by engaging other muscles which bend the arm. This is not a discredit to this exercise, quite the contrary, it is an excellent exercise to demonstrate the nature of Ki in Japanese arts. It is also and excellent exercise, which I use often to explain efficient biomechanics to students. I hope this has helped to clarify something for you. Don't get me wrong the use of the word Ki is not inappropriate or bogus, but it is often misunderstood as something magical, when it is in my experience talking about bioefficient movement. This notion is true also for the Chinese internal arts and traditional medical system, but the Chinese systems are applying it more broadly and with a wider scope than the typical Japanese systems. This is undestandable when you consider the fact that the ideas of Daoism and Confucianism from which the Chinese mode of health sprung forth pervade all aspects of Chinese history and thinking, it is only logical that this would extend to the Chinese martial systems. Dao
