A Biomechanical Analysis of the Karate Chop.

Although the sport of karate has been somewhat neglected by scientists, the following two isolated biomechanical studies exist in literature: (1) tracings of a karate chop in two planes were presented, but no data was given concerning the rates of movement of the limb segments, and (2) pre- and postimpact phenomena of five subjects were studied, and hand velocities and forces at impact were reported. This study attempts to provide additional data for the biomechanical analysis of the karate chop. An initial subjective analysis of five subjects using film taken at 200 frames per second identified three fundamentally different patterns of movement. Films were also taken to analyze the kinetic aspects of the study; they show the various components contributing to the accelerometer output. The various unknowns can also be calculated from film giving an interesting comparison of direct and indirect methods of estimating acceleration. The study uses the technique of accelometry to illustrate the differences in using preferred and nonpreferred hands to break boards. The accelometer recorded considerable differences during this experiment, and this technique may prove to be a useful teaching device which can provide immediate feedback. The study incorporates electromyographic results with kinematic and kinetic data to provide further insight into the movement to be obtained. Although the study is primarily concerned with preimpact phenomena, it also makes very approximate estimates of the forces existing at impact. (BD)