If you learn martial arts, one of the first things you get taught is how to make a fist properly. Classic mistakes include sticking the thumb inside the other fingers or curling it around the side. The right way is to wrap the thumb over the index and middle fingers. In this shape, the fingertips are cushioned against the pads of the palm, and the first two fingers are cushioned against the thumb pad and the thumb itself.

By getting martial artists to hit a punchbag, and measuring the forces acting on their fists, David Carrier and Michael Morgan from the University of Utah confirmed that this shape allows the various parts of the hand to buttress each other,