I came across your page and it feeds right into what I am doing.
I teach the 5 Tibetan Rites (as detailed in "Fountain of Youth" by Kelder). A question arose as to the proper breathing.
The book says breathe in through the nose, breathe out through the mouth. This feels right to me. But I then read in some esoteric yoga books from India that you always breathe in and out through the nose.
There are so many people that do not study the breath, pass themselves as experts and teach harmful practices.
Exhaling through the mouth is very bad information.
We uptake most of our oxygen during the exhale. The size of the nostrils creates back-pressure that holds air in a little longer so that the O2 has more time to be extracted from the air in the lungs.
The more you can function by breathing in and out through the nose the better except when singing or extreme states of fight, fight, freeze, faking it or fun. including sex). Then you will need to take in a lot of air and need both nose and mouth.
If you inherited your very large father’s lungs and your very small mother’s nostrils you will have to breathe in AND out through the mouth more often. This is an extreme and rare example but it illustrates better the issue of volume combined with air intake hole size. Click here