고관절각도에 따른 대퇴사두근의 등척성운동 효율성에 관한 연구

The purposes of this study were to investigate of the effective hip joint angle during quadriceps isometric exercise by electromyophic analysis. All participants performed quadriceps isometric exercise with knee flexion 60° by Cybex7000. The EMG activity of three knee extensor, vastus lateralis(VL), rectus femoris(RF), and vastus medialis(VM), in the subject' s isometric exercise(maximal voluntary isometric contraction, MVlC) was monitored using bipolar surlace electrodes. The magnitude of the average peak iEMG for each muscle monitored during the stactic motion is calculated as a percentage of the normalized peak iEMG during the MVIC. And the results were follows 1) Statistical analysis demonstrated significantly different maximal isometric force of quadriceps during changes of hip angle.(P＜.05) 2) Between 100° and 130° at hip angles, isometric force of quadriceps increased. Between 130° and 160° at hip angles, isometric force of quadriceps decreased. 3) Maximal isometric force of quadriceps was significantly increasing rate between 100° and 110° at hip angle.(P＜.05) 4) Maximal isometric force of quadriceps was significantly decreasing rate between 140° and 150° at hip angle.(P＜.05) 5) The isometric force of rectus femoris during changes of hip angle was significantly different (P＜.05) 6) The VL/RF, VL/VM, RF/VM iEMG ratios during changes of hip angle was significantly different(P＜.05)