LOWER EXTREMITY BIOMECHANICAL ANALYSIS OF A STOP-JUMP TASK WITH DIFFERENT STEP LENGTHS IN THE APPROACH RUN

Abstract

This study aimed to assess the kinematics and kinetics during the landing phase of 3 kinds of last step lengths in a stop-jump task to provide further perspectives on lower extremity injuries. Twelve adult males were recruited for the study. A MegaSpeed high-speed camera synchronized with an AMTI force plate was used to record the stop-jump action. Kinetic parameters were calculated using an inverse dynamic method. The results showed that the kinematical characteristics of landing were similar among the different last step lengths during the approach run. The peak vertical ground reaction force and vertical loading rate during landing significantly increased as the step length increased. The peak knee extension moment and proximal tibia anterior shear force did not differ among the 3 stop-jump tasks. These results suggest that during the stop jump task, longer last step lengths during the approach run may increase lower extremity injury.