title: The acute benefits and risks of passive stretching to the point of pain.
abstract: OBJECTIVE
  This study evaluated the acute effects of two different stretch intensities on muscle damage and extensibility.
  
  
  METHODS
  Twenty-two physically active women (age 20 ± 1.0 years) were divided into two matched groups and undertook eight sets of 30-s passive hamstring stretching. One group stretched to the point of discomfort (POD) and the other to the point of pain (POP). Hamstring passive torque, sit and reach (S&R), straight leg raise (SLR), and markers of muscle damage were measured before, immediately after stretching and 24 h later.
  
  
  RESULTS
  S&R acutely increased and was still increased at 24 h with median (interquartile range) of 2.0 cm (0.5-3.75 cm) and 2.0 cm (0.25-3.0 cm) for POP and POD (p < 0.05), respectively, with no difference between groups; similar changes were seen with SLR. Passive stiffness fully recovered by 24 h and there was no torque deficit. A small, but significant increase in muscle tenderness occurred at 24 h in both groups and there was a very small increase in thigh circumference in both groups which persisted at 24 h in POP. Plasma CK activity was not raised at 24 h.
  
  
  CONCLUSIONS
  Stretching to the point of pain had no acute advantages over stretching to the discomfort point. Both forms of stretching resulted in very mild muscle tenderness but with no evidence of muscle damage. The increased ROM was not associated with changes in passive stiffness of the muscle but most likely resulted from increased tolerance of the discomfort.
authors.affiliation: Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania. pornpimolm@buu.ac.th.
authors.forename: Pornpimol
authors.initials: P
authors.lastname: Muanjai
authors.affiliation: School of Healthcare Science, Manchester Metropolitan University, Manchester, England, UK.
authors.forename: David A
authors.initials: DA
authors.lastname: Jones
authors.affiliation: Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania.
authors.forename: Mantas
authors.initials: M
authors.lastname: Mickevicius
authors.affiliation: Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania.
authors.forename: Danguole
authors.initials: D
authors.lastname: Satkunskiene
authors.affiliation: Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania.
authors.forename: Audrius
authors.initials: A
authors.lastname: Snieckus
authors.affiliation: Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania.
authors.forename: Albertas
authors.initials: A
authors.lastname: Skurvydas
authors.affiliation: Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania.
authors.forename: Sigitas
authors.initials: S
authors.lastname: Kamandulis
mesh_terms: D003402:Creatine Kinase / Q000097:blood; D005260:Female; D000070633:Hamstring Muscles / Q000502:physiology* / Q000503:physiopathology; D006801:Humans; D009119:Muscle Contraction; D052580:Muscle Stretching Exercises / Q000009:adverse effects*; D063806:Myalgia / Q000209:etiology / Q000503:physiopathology*; D019415:Torque; D055815:Young Adult
chemical_list: D003402:Creatine Kinase
keywords: Constant torque stretching; Flexibility; Muscle damage; Passive stiffness; Stretching intensity