ASYMMETRY OF LOWER-EXTREMITY RESPONSES TO EXTERNAL IMPACT LOADING

The purpose of this study was to determine if the lower limb cushionin g responses to impact loading were asymmetrical. A human pendulum was used to quantify impact loading and the shock wave that traveled throu gh the locomotor system. Twenty-four healthy adults impacted a wall mo unted platform 40 times with each foot while their leg was flexed 20 d eg at the knee. Time and frequency analyses were performed, asymmetry was expressed according to a lower limb strength dominance index. No s tatistical differences were found between dominant and non-dominant li mbs, however, histogram representations of the results revealed that 6 5 percent of the subjects responded asymmetrically. The asymmetry coul d not be linked to leg strength dominance. The magnitude and high inci dence of asymmetrical responses under controlled inital lower limb kin ematics suggested that the contribution of the lower limbs' structural properties and levels of muscular activation to bilateral asymmetry c ould be paramount during locomotion.