Alison McConnell, now a professor in sport/health science at Bournemouth University and author of Breathe Strong, Perform Better, broke it down for us a few years back:
1. A player inhales before each shot and the tension from that inflation of the lungs stabilizes the body’s core
2. That pneumatic pressure inside the trunk optimizes the shot
3. Players then release that air in a way that doesn’t destabilize the body by restricting air flow with their larynx and vocal chords, like squeezing the neck of a balloon.