Yes it does, thanks for posting. So when screaming the sudden burst of aggression triggers a shot of adrenaline and a higher heart rate, increasing blood flow to the limbs and organs. The lungs contract aggressively forcing oxygenated blood to the extremities (in this case the fists). As the scream suddenly releases from the body the entire core muscle group contracts at once (in this case for body shots).
:good no problem. I'm glad you made me look it up again myself, because it was a while since I saw the video