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Principle of Aiki and its Application in Aikido and Aikijujutsu



Welcome to the Site of Alun Harris!

Aiki is the method of unbalancing an opponent in the martial arts of Aikido and Aikijujutsu. The nature of Aiki has been shrouded in mystery. Consequently, learning Aiki based techniques has been problematic, as a failure to unbalance the opponent will undermine the whole technique. My interest in Aiki started over twenty years ago with the aim of understanding what is Aiki and, is it the same in Aikido and Aikijujutsu? Furthermore, how does Aiki differ from the unbalancing methods used in Judo, Jujutsu and wrestling? The results of this research resulted in articles being published in Aikido Journal and the Aikido Times of the British Aikido Board. Since the publication of these articles, a deeper understanding has been achieved. This has led to a meaningful and practical definition of Aiki which is given below:-

"Aiki is a method of unbalancing Uke that reverses the rotation of a muscular torque which Uke depends on to maintain his balance"

On the next page I have given a brief guide on how to apply Aiki taking into account the natural processes that the body uses to maintain its balance.


The bio-mechanics that underpin this definition of Aiki and its application in the techniques of Aikido and Aikijujutsu are detailed in a Kindle book published by Amazon. The title of the book is " The Principle of Aiki and its Application in Aikido and Aikijujutsu".  This book also includes demonstrations which allow you to experience the unbalancing effect of Aiki. Although this link takes you to the UK Amazon site, this publication is available on all Amazon sites throughout the world and can be viewed on all computers, tablets and smart phones with the free Kindle App. This book is also available on Amazon in a paperback format.

YouTube Videos

In the remaining pages of this site I have analysed how Aiki has been applied in the techniques demonstrated on YouTube by well known Sensei. Techniques are also grouped together where the method of attack is the same. For simplicity, the Aikido description for the attack is used for both Aikido and Aikijujutsu techniques. 

When viewing the YouTube footage slow the video down, ideally to a point where you can view it frame by frame. This will allow you to clearly see the application of Aiki.