Exhale

Gradually expel the air contracting the abdominal muscles, pushing them down and forward. In other words, work on the air column from B to A, as if you were a piston (fig. 2/2A)

The contrast between the diaphragm, that rises, and the abdominal muscles, that push down and forward. This is a single and continuous phase: appoggio and sostegno are one the result of the other.