[quote=124908:@Alwyn Bester]Apparently the moaning (grunting) relaxes the player and helps with the rhythm of how they’re hitting the ball and how they are pacing things.
Not sure why this is only done in tennis? Maybe it also happens in squash?[/quote]
Shot-put, Karate … Just listen to these guys. I was teaching Karate for more than 10 years at the University of Basel and I could tell just from listening to their ‘Kiai’ whether someone was able to transfer his whole energy into a punch. It makes a big difference whether you release your energy while breathing out instead of blocking your breath. After some time the sound comes like all by itself.