Anatomy of a 1-Punch Knockout - Video

This video confirms the legend about the one-punch knockout. The strongest punch belongs to no martial artist.  But rather, the strongest punch belongs boxing.

This is the anatomy of what happens to the body when you are punched very hard.  It sends the brain sliding inside the skull - the skull accelerates and decelerates rapidly but the brain keeps moving and recoils towards the back of the head, then snaps to the front - trauma from both sides causes a severe concussion.

And size does matter - the bigger the puncher, the more mass in the whiplash.

Check out what Bruce Lee had to say about the Punch.