title: Acute effects of hamstring-stretching exercises on the kinematics of the lumbar spine and hip during stoop lifting.
abstract: BACKGROUND
  Hamstring-stretching exercises are frequently used to change lumbar spine and hip movements in the clinic. However, little research into the effects of hamstring flexibility on lumbar spine and hip movements during lifting tasks has been reported.
  
  
  OBJECTIVE
  We investigated effects of hamstring-stretching exercises on the kinematics of the lumbar spine and hip during stoop lifting.
  
  
  METHODS
  We recruited 16 males with a reduced range of motion (ROM) in active knee extension (AKE). The angle of the lumbar spine and hip was measured during stoop lifting using a 3D motion-capture system. The ROM of AKE and the angle of the lumbar spine and hip during stoop lifting between pre- and post-stretching were analyzed using a paired t-test.
  
  
  RESULTS
  We found that hamstring-stretching exercises increased the ROM of AKE significantly. After hamstring-stretching exercises, there was a significant increase in hip flexion and decreases in both lumbar flexion and the lumbar/hip flexion ratio during the preparation phase of stoop lifting. In the lifting phase, only the movement range of the hip was increased significantly.
  
  
  CONCLUSIONS
  Hamstring-stretching exercises may be useful for decreasing lumbar flexion and increasing hip flexion in people who perform repetitive stoop lifting in the workplace or during daily activities.
authors.affiliation: Department of Rehabilitation Science, Graduate School, INJE University, Gimhae City, Korea.
authors.forename: Min-Hyeok
authors.initials: MH
authors.lastname: Kang
authors.forename: Doh-Heon
authors.initials: DH
authors.lastname: Jung
authors.forename: Duk-Hyun
authors.initials: DH
authors.lastname: An
authors.forename: Won-Gyu
authors.initials: WG
authors.lastname: Yoo
authors.forename: Jae-Seop
authors.initials: JS
authors.lastname: Oh
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D006621:Hip Joint / Q000502:physiology*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007719:Knee Joint / Q000502:physiology; D008159:Lumbar Vertebrae / Q000502:physiology*; D008297:Male; D009068:Movement / Q000502:physiology; D052580:Muscle Stretching Exercises; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular; D055815:Young Adult