The 19th century Italian schools of singing had alot of cool things to say about posture, and how it affects singing.
In the Noble Posture, the sternum is raised along with the upper chest ‘like a soldier in a relaxed position’. This frees the lower ribs and subsequently the lungs for maximum outward movement when inhaling.
All the muscles concerned with the action of healthy balanced singing are now ready to engage. If this Noble Posture is maintained as long as possible during the action of singing an unexpected benefit occurs: the muscles of inhaling are not allowed to ‘collapse’ during exhaling but act as natural antagonists to the muscles of breathing out. This antagonistic relationship or ‘vocal struggle’ (called La Lotta Vocale in the Italian School) has the exhalation resisted by the inhalation muscules and a controlled stream of breath at the larynx is possible. The breath is kept alive by ‘leaning’ the breath against the nobly raised front wall of the chest (called appogiato).
