> On Mon, 10 Apr 2000, Lloyd Hanson wrote:
>
> The diaphragm descends only to a flat position at the bottom of the rib
> > cage during the inhale. It is not able to actively descend below
> > this level.
A question or two;
This statement implies that the diaphragm descending to a flat position
would require no displacement of abdominal cavity contents. If this were true
then there would have to be either a vacume in the abdominal cavity directly
below the diaphragm or a method by which abdominal contents shift above or into
the thoracic cavity; neither of which seems to be physiologically likely.
> For this reason, there is no advantage to releasing the
> > lower abdominal muscle wall (commonly called "belly" breathing) to
> > make more room for the diaphragm or to attempt to take a larger
> > breath. Breath capacity studies have shown that this release of
> > lower abdominal muscles actually reduces the breath capacity because
> > it tends to encourage the rib cage to sag slightly.
I would love to read those studies. In Ingo Titze's book on voice physiology
"Principles of Voice Production" he has an extensive section on breath
mechanics. On page 67 he states: "In the inspiratory phase, abdominal muscles
and internal intercostal muscles must relax quickly to allow rapid expansion of
the lungs. Negative recoil will help, but the primary effort comes from the
external intercostal muscles and the diaphragm. An outward displacement of the
tissue in the region of the stomach is an indication that the diaphragm is
lowering."
My understanding of the Italian principles of Appoggio and the Lotta Vocale
require a resistance to the inward contraction of the abdominal muscles by
keeping the muscles of inspiration active in a balanced resistance. Any
sagging of the rib cage should be resisted of course.
--
Dr. Barry Bounous
Brigham Young University
School of Music
bounousb@i...
|
