The exhalation of air produces a sinusoidal wind current to increase the velocity and force of the intended punch. Or it impresses the judges.
I just take it as younger fighters who were way into RJJ and imitated him long enough they co-opted his noises.
exhaling also help keep your core tight, kept caught to the body whilst breathing in and you will know about it
Baldomir even sings "my way" when he throws punches. He would be halfway through the song when he throws his second punch. It actually helps in the timing of throwing combinations. When you practice countless times with drills in throwing combos, some fighters using these timing clues.
It allows for proper breathing and like others have said, it helps tighten the core. Hell it can also be a feinting tool.
Bernard Hopkins "yaps" when he punches, like the alsation puppy he shares an IQ score with. Andre Ward makes a goat noise each time he headbutts an opponent. Andre direll blows a raspberry to tell you his nappy needs changing.
Why do you think power lifters yell? Or Tennis players scream? It's to generate more power. Same thing with boxing and I know it works because I've been doing it for 3 1/2 years :nut You can try it yourself. Hold your breath and start punching and see how slow you go and how quick you get tired
You're supposed to punch with your fist parrell to the ground and not at a 90 degree angle (ubless it's a hook). The main thing is to make sure you are punching with your knuckles. The best example is the hook This content is protected In this picture above, Floyd isn't turning his hook over. When you turn it over, it give you more power and it brings your shoulder up so it can protect you from counters You can throw the hook vertical or horzinal. Here's an example of turning a hook over This content is protected
This is a good point. I'd also like to add that when you turn the hook over, you have better skeletal alignment and thus a stiffer, "harder" punch.
Okay but that didn't answer my question. Like I say, I'm not doubting it for a second, just interested to know the science behind it. If you don't know, that's fine.