ABDOMINAL SUPPORT OF AIR This is one of the areas of brass playing that causes a great deal of confusion. Much discussion about the importance of the diaphragm has sent many a player down the road to confusion, inability, and bleeding lips. The upper part of the torso contains a large FAMILY of muscles that all have been designed to function in a teamwork fashion specially when we do something requiring FORCED EXHALATION, i.e., blowing out candles, spitting something out of our mouth, OR BLOWING ON A WIND INSTRUMENT. There are 3 layers of abdominal muscles from the groin to the sternum (breastplate); there are 2 layers of muscles (inner and outer) in between the ribs; there are back muscles from the lumbar region upward to the shoulders; there is the diaphragm just below the lung sacs; and there are muscles coming-down diagonally from behind the ear which connect to the top of the rib cage . When a person does a "forced exhalation", the entire family is activated as a "one-family" movement. They ALL simultaneously increase their tension levels in order to raise the internal compression level (PSI) in the lung chambers. This moves the air FASTER which is one of the first necessary things that must occur when a player moves "upward" in the register. The area that the player needs to become aware of is NOT in the diaphragm but in the center of the abdominal muscles, approximately near the navel. The body has a natural way of centering itself if you only just try to blow suddenly as if spitting a piece of rice or blowing out a candle. By learning to control the variance of tension, either isometric for holding a compression level or by tightening and relaxing the degrees of tension based upon what you are playing, one discovers that it is really the abdominal support that controls the air. This ab support certainly influences the diaphragm but it is NOT the diaphragm alone that moves the air. It is the FAMILY of muscles, all guided by the abdominal centering.