Poster Session II, July 14th 2010 — Abstracts A study on improving performance in vertical jump motion considering bi-articular muscle function

AbstractThe analysis and clarification of human physical properties in sport and welfare engineering is vital, and the results of these types of studies will contribute to the improvement of physical abilities, the prevention of sports injuries, and the rehabilitation of physical defects.The purpose of this study is to estimate muscle power of lower limbs during vertical jump motion using human musculoskeletal model considering bi-articular muscle function and to evaluate the effect of the muscle power to the jump performance.The musculoskeletal model used in this study includes both antagonistic muscle and bi-articular muscle. Antagonistic muscle is a muscle generates bending and stretching motions with one joint. Bi-articular muscle is a muscle, which attaches at two joints, generates motion with two joints. The property of bi-articular muscle makes a great variety of human motions.In this study, vertical jump motions performed by 5 subjects, who are athletes of our university, are analyzed.Jump performance will be improved to modify output force direction and amplitude generated by muscles of lower limbs. The subjects, whose output force directions were not good for the jump posture, can improve their jump performance by modifying their jump postures. The subjects, whose output force directions were good for the jump posture, can improve their jump performance by training their mono-articular muscles locating on knee joint.Thus, the additional technical advice can be made based on the muscle function beside of the investigation of joint angle, joint force and torque