title: Acute changes in passive stiffness and range of motion post-stretching.
abstract: OBJECTIVE
  To investigate the change in passive hamstring stiffness and knee joint range of motion (ROM) following a single bout of passive hamstring stretching with or without active movement post-stretch.
  
  
  METHODS
  A Kincom dynamometer was used to measure knee joint ROM and passive stiffness in nine participants. Each participant completed three conditions: (1) a baseline test of knee extension ROM and passive stiffness, 4×20 second static stretches of the hamstring muscles and repeat testing immediately post-stretch and at 5min intervals for 20min; (2) the same procedure with the addition of 90s of isotonic knee flexion and extension between tests over the 20min post-stretching period; (3) the control condition involving repeat tests only over 20min.
  
  
  RESULTS
  Knee joint ROM increased by 4-5° post-stretch in both intervention conditions, relative to the control condition, but there was no clear evidence of the ROM increase lasting longer than 5min. Both intervention conditions showed a small decrease in passive stiffness post-stretch and it is likely this effect lasted for at least 20min.
  
  
  CONCLUSIONS
  An isolated bout of stretching produced a small, short-lived change in ROM and stiffness. This has implications for the design of warm-up protocols.
authors.affiliation: Institute of Sport and Recreation Research New Zealand, Faculty of Health and Environmental Sciences, Auckland University of Technology, New Zealand; Physical Rehabilitation Research Centre, Faculty of Health and Environmental Sciences, Auckland University of Technology, New Zealand.
authors.forename: Chris
authors.initials: C
authors.lastname: Whatman
authors.forename: Alice
authors.initials: A
authors.lastname: Knappstein
authors.forename: Patria
authors.initials: P
authors.lastname: Hume