title: Comparison of gluteus maximus and hamstring electromyographic activity and lumbopelvic motion during three different prone hip extension exercises in healthy volunteers.
abstract: OBJECTIVE
  To compare the surface electromyography (EMG) amplitude of the hip joint, including the gluteus maximus (GM), biceps femoris (BF), and semitendinosus (ST) muscles generated by three different exercises: prone hip extension (PHE), prone table hip extension (PTHE), and prone table hip extension with 90° knee flexion (PTHEK), with compensatory pelvic motions.
  
  
  METHODS
  Repeated-measure within-subject intervention.
  
  
  METHODS
  Sixteen-healthy males (mean age = 23.4 ± 2.2 years).
  
  
  METHODS
  EMG was used to collect EMG signals from the GM, erector spinae (ES), BF, and ST muscles. Furthermore an electromagnetic tracking motion analysis was also performed to measure the compensations.
  
  
  RESULTS
  EMG amplitude differed significantly among the three conditions (PHE vs. PTHE vs. PTHEK) (p < 0.05). The mean GM muscle activity increased significantly during the PTHEK (70.93% and 13.75% increases in %MVIC compared with the PHE and PTHE, respectively) (p < 0.01). However, there was no significant difference in the kinematic data for rotation or anterior tilting angle of the pelvis among the three conditions (p > 0.05).
  
  
  CONCLUSIONS
  These results suggest that the PTHEK can be recommended as an effective method to strengthen the GM muscle without increased BF or ES muscle activities and without compensatory pelvic motions.
authors: Department of Physical Therapy, Graduate School, Yonsei University, Wonju, South Korea. Electronic address: jeon6984@naver.com.
authors: In-Cheol
authors: IC
authors: Jeon
authors: Department of Physical Therapy, Graduate School, Yonsei University, Wonju, South Korea. Electronic address: hwangu33@nate.com.
authors: Ui-Jae
authors: UJ
authors: Hwang
authors: Department of Physical Therapy, Graduate School, Yonsei University, Wonju, South Korea. Electronic address: jsh881225@naver.com.
authors: Sung-Hoon
authors: SH
authors: Jung
authors: Department of Physical Therapy, College of Health Science, Laboratory of Kinetic Ergocise Based on Movement Analysis, Yonsei University, Wonju, South Korea. Electronic address: kwonoy@yonsei.ac.kr.
authors: Oh-Yun
authors: OY
authors: Kwon
mesh_terms: D001696:Biomechanical Phenomena; D002081:Buttocks / Q000502:physiology; D004576:Electromyography; D015444:Exercise / Q000502:physiology*; D064368:Healthy Volunteers; D006621:Hip Joint / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D010388:Pelvis / Q000502:physiology*; D016684:Prone Position; D016059:Range of Motion, Articular / Q000502:physiology; D055815:Young Adult
keywords: Gluteus maximus; Lumbopelvic stability; Prone hip extension