One of the foundations of learning to sing correctly is knowing how to breathe correctly as well as learning how to correctly control the way you breathe so that when you are singing your breathing is being used to optimum effect.
As soon as we are born our breathing is naturally correct. A baby can breathe, yell and scream at optimum capacity because they are using their lungs without any conscious thought. However, as we grow older some people become lazy in how they breathe and breathe using only the upper part of their lungs – taking a shallow breath instead of a normal breath.
Understanding how to correctly breathe and use breath control, you need to first understand the process involved to help you achieve this. Our lungs are surrounded by a system of muscles known as the diaphragm. The diaphragm is attached to the lower ribs – on the sides, bottom and to the back acting as an inhalation device. When we take a breath in the whole muscle lowers displacing the intestines and stomach and when you breathe out the diaphragm helps to manage the abdominal muscles surrounding the lungs control how quickly the breath is exhaled.
If you hold a finger close to your lips and breathe out slowly, your breath should be warm and moist and you should notice the action of the diaphragm as you exhale. For singing normally this is the correct amount of breath that should be used. A singer does not need to 'force' or 'push' air through the vocal chords to produce a good strong sound, doing so creates too much pressure against the chords, preventing them from operating correctly which can cause damage to the voice.
Your stomach area should move naturally inward toward the end of the breath but it should not be sucked in as doing this will prevent the diaphragm working effectively. Instead the abdominal area should remain expanded to the level it was when you inhaled and allowed to gradually decrease naturally at the end of the breath.
At this point ‘control’ comes into play. As a singer you expand your lungs by inhaling therefore controlling the amount of air that is expelled when singing a note by allowing the muscle support system to remain expanded - this doesn't mean the stomach is pushed out, rather that it is blown up like a balloon when the air goes in and the singer slows down the natural rate at which it goes down. In most people the breathing is shallow and only the top half of the lungs are used - breathing correctly uses the whole of the lungs so that more air is available, the singer then uses the natural action of the muscles (diaphragm and abdominals) surrounding the lungs to control the amount of air that is exhaled when singing a note.
Good breath support during singing and speech requires good posture, abdominal breathing and breathing during natural pauses. Breathing and correct support does not require great physical strength - although having toned abdominal muscles and doing some vocal exercises does help.
However, it is important to remember one thing.......the diaphragm doesn't exhale for you - just helps to control the amount of air exhaled.