Effects of a Combined Posture of the Lower Extremity on Activity of the Vastus Medialis Oblique Muscle and Vastus Lateralis Muscle During Static Squat Exercise

정적인 스쿼트 운동시 복합적인 하지의 자세가 가쪽넓은근과 안쪽빗넓은근의 근활성도에 미치는 영향

  • Yoo, Won-Gyu (Dept. of Rehabilitation Therapy, The Graduate School, Yonsei University) ;
  • Yi, Chung-Hwi (Dept. of Physical Therapy, College of Health Science, Yonsei University, Institute of Health Science, Yonsei University) ;
  • Lee, Hyun-Ju (Dept. of Physical Therapy, Andong Science College)
  • 유원규 (연세대학교 대학원 재활학과) ;
  • 이충휘 (연세대학교 보건과학대학 물리치료학과 및 보건과학연구소) ;
  • 이현주 (안동과학대학 물리치료과)
  • Published : 2004.09.17


Most exercise for Patellofemoral pain syndrome (PFPS) has focused on selectively strengthening the vastus medialis oblique muscle (VMO). Although open chain knee extension exercises are effective for increasing overall quadriceps strength, they are not always indicated for PFPS rehabilitation. This study was designed to identify the effect of combined posture of lower extremity on Electromyographic (EMG) activity of the vastus lateralis muscle (VL) and VMO during static squat exercises. The subjects were twenty young adult males who had not experienced any knee injury and their Q-angle was within a normal range. They were asked to perform static squat exercises in five various postures using their lower extremities. The EMG activity of the VL and VMO were recorded in five exercises by surface electrodes and normalized by %MVC values derived from seated, isometric knee extensions. The normalized EMG activity levels (%MVC) of the VL and VMO for the five postures of the lower extremities were compared using one way ANOVA with repeated measures. Results of repeated measures of ANOVA's revealed that exercise 3 and exercise 5 produced significantly greater EMG activity of VMO/VL ratios than exercise 1 (p<.05). When the static squat exercise was combined with hip adduction and toes pointed outwardly, the EMG activity of VMO/VL rates was increased. The EMG activity of VMO/VL ratio was highest during static squat exercises performed on a decline squat. These results haveimportant implications for progressive and selective VMO muscle strengthening exercises in PFPS patients.