Impact forces at the knee joint: A comparative study on running styles

The focus of this study was to quantify changes in impact forces at the knee when changing footstrike. The subjects included 17 heelstrikers (trained = 8, controls = 9). The 12-week training consisted of drills that focused on landing on the midfoot as per the Pose Method of running. The kinematics variables quantified were stride rate, stride length, stance phase, and knee flexion angle at footstrike. The kinetics measured were maximum vertical ground reaction forces at the ground and at the knee joint during initial impact, and maximum loading rate. The data were analyzed with a repeated measures ANOVA with (P < 0.05). Significant decreases was found in stride rate, stance phase and in all kinetic variables. These preliminary results are encouraging because they demonstrate that changing the footstrike can result in a reduction in impact forces at the knee joint.