Striking Surface

Any martial artist who has ever struck a board with improper hand technique can
attest to the physical pain associated with such impact. The human had is a complex
system of bones connected by tissue, and much can be said about the importance of
proper hand alignment in breaking. From the standpoint of physical science, however,
what is crucial about hand position upon impact is that all formulae for force,
momentum, and deformation energy are for a given unit of area. By minimizing the
amount of striking surface on the hand involved in collision with the board, a karateka
minimizes the area of the target to which force and energy are transferred and
therefore maximizes the amount of force and energy transferred per unit area.