What is support?
Support is the control of air pressure in such a way as to maintain accurate pitch, consistent volume and tone quality, and to sustain these to meet the requirements of any given phrase of music. Appoggio is an Italian term used to mean the same thing, except that this term embraces issues of resonance at the same time. (10)
How is it achieved?
Air pressure is influenced by how much air is in the lungs, and the extent to which it is being ‘squeezed’, either by the forces of elasticity or by active contraction of certain muscles.
The internal intercostal muscles (muscles connecting the insides of the ribs) are able to ‘squeeze’ the air in the lungs, as are the abdominal muscles. However, the central rectus abdominis muscle (the one you use for sit-ups) is too large and powerful for fine control, and the smaller, layered oblique abdominal muscles at the side are used in preference. Contraction of these muscles will cause the stomach wall to remain forward for quite some time during the exhalation/singing process.
A common error in beginners striving for ‘more support’ is to pull in on the stomach wall (i.e. using the large central muscle). This produces an abrupt burst of air pressure which is then difficult to maintain.
How do I teach support?
It is probably true to say that I avoid ‘teaching’ support, because I believe that it is a fairly natural phenomenon for most students. If the beginning singer has good posture and is breathing correctly, there will usually be enough support for the modest technical difficulties encountered in the early stages of training.
In order to increase the singer’s awareness of the mechanism in preparation for the greater demands which will later follow, there are a number of available exercises. These include sustained hissing exercises which develop to a delightful degree the ability to alarm one’s cat (described in some detail in James C. McKinney’s “The Diagnosis and Correction of Vocal Faults”). (3) The onset exercises referred to in the phonation section are also an excellent way of discovering the correct mechanism.
Please read my note regarding the different approaches to posture and breathing taken by the various national schools of vocal pedagogy, in the Posture section.
A technical note
There has historically been disagreement as to whether support is achieved by the abdominal muscles alone, or by a combination of the diaphragm and the abdominal muscles working against one another (sometimes called ‘co-contraction’). Leanderson, Sundberg & von Euler (1987) (4) suggest that the diaphragm may co-contract, particularly in the early stage of exhalation, but that this varies from one professional singer to another, so no definitive prescription can be given.
As a practical matter, without the benefit of biofeedback a singer has no way of knowing for certain whether the diaphragm is co-contracting or not, since it is one of those parts of the body without the necessary nerve receptors. I address this issue by establishing clearly understood objectives in terms of the resulting sound, and letting each individual discover their own personal means of achieving them.