Posted by AAR on September 13, 2003 at 22:00:04:
Here is a short treatise on the diaphragm to help clarify some less than correct information often published on music boards and music websites.
The statement "The diaphragm is an involuntary muscle" is true - sometimes, but not always. It functions as an involuntary muscle when we sleep, run out of breath, or breathe without conscious attention to inhaling and exhaling.
But it also functions as a voluntary muscle under certain conditions: Almost everyone exercises conscious control of the diaphragm when speaking, and musicians do it all the time when playing wind instruments, and singing. Please consider the following discussion.
The diaphragm is the principle muscle of inhalation (the principle muscles of exhalation are the abdominal muscles). Inhalation is accomplished by contracting the diaphragm, thus lowering air pressure in the chest cavity, and allowing normal outside air pressure to push air into the lungs. The diaphragm does not expel air. It assists in exhalation only slightly as it relaxes to its normal position and shape. Muscles do not "push". They only "pull" by contracting.
Every time we take a breath to sing or play, (or hold our breath) we are exercising voluntary control over the diaphragm: When we start to play or sing a phrase, we consciously contract the diaphragm, lowering air pressure in the chest cavity, thereby allowing air to flow into the lungs. (The act of inhalation is conscious as such, however, we do not feel the diaphragm contracting, only the results of that contraction) The air is then pushed into the lungs due to normal air pressure outside the body being greater than the air pressure inside the chest cavity.
In singing, the abdominal muscles (and other related muscles) contract, expelling air through the contracted vocal folds (cords), forcing them to vibrate.
In playing a wind instrument, the abdominal muscles contract, expelling air through the opened vocal fold, and cause lips to buzz against a brass mouthpiece, or a reed to vibrate, or a column of air to be excited as the air stream hits the edge of a flute mouthpiece opening, etc.
Many music teachers often use imagery that is at odds with the laws of physics, or with anatomical structure. This is both acceptable and effective practice, since students respond well to imagery in engaging the proper muscles to perform. For example, asking singers to raise the uvulum and velum palatinum (soft palate) may be meaningless to them, whereas having them start a yawn will accomplish the objective easily.
Many music teachers, having inadequate knowledge of human anatomy and the breathing process, too often unwittingly disseminate incorrect information and concepts about techniques of breathing and breath control in singing and playing. Mesage boards like this can help enlighten readers interested in this topic.
Regards,
Dr. Anastasio A Rossi
Director of Music (ret) Mount Pleasant School System
Former Director, Pace University Glee Club
Director Golden Apple Chorus
Associate Director, Music VP,Westchester Chordsmen