Περίληψη:
The purpose of the study was to detect bilateral asymmetry in the lower extremities by investigating the kinetics and kinematics of the stride in normal gait under various loading conditions. It was hypothesised that the vertical components of the ground reaction forces and the vertical impulse would be larger in the non-dominant limb during the first distinctive phase of the stride whilst the dominant limb was expected to present larger anteriorposterior ground reaction forces and propulsive impulse during the second phase. The center of mass was expected to travel mainly on the non-dominant side, as its lateral movement is associated with the lateral stability of the body during gait (Hsiang S.H. and Chang C., 2002). The stride was divided into a braking and a propulsive phase of the anterior-posterior ground reaction force. Six young healthy adults participated in the study. All components of the GRF were collected and analyzed using a Kistler force platform. Also, the kinematics provided the medio-lateral motion of the center of mass throughout the strides as they were collected and processed using the Vicon Nexus. The results showed that although asymmetries existed in every variable, the additional load did not increase the observed differences between the two legs. Also, the asymmetries were not consistent across the subjects in the vertical components of the force and the relative impulses. On the contrary, the propulsive impulse was significantly larger in the dominant limb. The center of mass mainly traveled on the dominant side which was not expected. Overall, power generation is associated with the dominant limb. However, power absorption and stability functions are unlikely to be a feature of the nondominant limb based on this study. This conclusion can also be supported by the direction of the asymmetry observed in the center of mass lateral oscillation. © JPES.
