Appreciate the reply
Actually we don't really focus on the breathing where I train, but I know some elementary components of it, and it overlaps with my own training.
The expansion you mentioned Ushiro using is more what I was referring to. Inhaling can "close" the body, while exhaling can expand/opens "something" in the body.
I can do the test you mentioned as well, but I most definitely could probably not do it with the Jo, lol.
Using the breath "correctly" can only enhance the ability to do the test, and shouldn't prevent a person from completing it.
Thanks you. I should make it clear that I have never been a student of Ushiro. I merely observed him up close during demonstration he gave in Tokyo some years back. I recall him talking about breath power, and I just started experimenting with it on my own and found the expansion thing. There is also a rising a falling aspect to breathing that maybe of use...