Low Limb Muscle Activation and Joint Angle in the Sagittal Plane During Drop Landing from Various Heights

[Purpose] The purpose of study was to verify various strategies for the prevention of injury in normal adults and to identify the risk factors of body injury by the biomechanical analysis of drop landing with selected external loads that are commonly experienced in daily living causing load on the foot, ankle and the entire body as well as an increase in impulse. [Subjects] The subjects of this study were 14 normal adults. [Methods] Measurements were carried out while the participants drop-landed from the heights of 20, 40 and 60 cm. [Results] The muscle activation of the individual muscles until the posture was stabilized significantly increased in the abductor hallucis, medial gastrocnemius, biceps femoris and vastus lateralis as the drop height increased. In addition, the movement of the individual joints to correct the posture while landing showed that the flexion angles of the hip joint and knee joint increased as the drop height increased. [Conclusion] We found that there was a great change in the muscle activation at the drop height of 40 cm and the flexion angle also changed at the drop height of 40 cm, indicating that 40 cm may be the drop height at which the strategy for the postural balance of humans changes while landing.