Oyayubi Ippon Ken

Oyayubi-ken (亲指拳) , or Oyayubi Ippon Ken (亲指一本拳), is performed with the fist in a similar way to seiken but with the thumb protruding in a triangle, that is, the tip of the thumb rests against the closed index finger, right in its center. 

A blow delivered with this technique is very powerful, which makes it dangerous and unsuitable for sports competitions. 

As such, its practice in training should be very cautious and never used in kumite , as it can accidentally cause fainting and even death, given that the points targeted on the opponent are, in most cases, the base of the ears and the temple.

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