The IAI-DŌ uses the real Japanese sword unlike KEN-DŌ.
A main thing is a thing pursuing the movement along the flow called ENBU(演武), but does what's called test of.
The sense when I was able to cut it in a real Japanese sword slashingly does not feel weight at all and is very light. There is no sense that anything was.
The IAI-DŌ that I do is called HOUKIRYU, and it is said to the model of the chief character of comics ″SAMURAI X" that I learned assassin by the late Tokugawa period when it was, GENSAI KAWAKAMI.