Influence of Resistance Positions of Shin on Muscle Action of Quadriceps Femoris during Knee Extension

Abstract

[Purpose] The purpose of this study was to determine whether resistance positions of the shin during knee extension influence muscle action of the quadriceps femoris.[Subjects] The subjects were seven healthy males.[Methods] The actions of the vastus medialis (VM), vastus lateralis (VL), and rectus femoris (RF) were measured by electromyography. We imposed resistance on the leg using dual shin pads or a single pad during isometric contraction with knee flexion at 90 degrees.[Results] The muscle activities of RF and VM increased significantly at 60% of maximum voluntary isometric contraction with dual shin pads.[Conclusion] These results suggest that the muscle action of the quadriceps femoris may be increased by use of dual shin pads in isometric contraction exercises.