title: Acute effect of different time periods of passive static stretching on the hamstring flexibility.
abstract: BACKGROUND
  Several factors are associated with the presence of chronic low back pain; one of them is the flexibility of the hamstring muscles that influences the posture of the pelvic spine.
  
  
  OBJECTIVE
  Investigate the influence of two different time periods of passive static stretching on the flexibility of the hamstring.
  
  
  METHODS
  Forty-six physiotherapy students were divided into two groups performing stretching exercises: 30 s and 60 s duration. The collections consisted of: (1) pre-test: evaluation of the flexibility of the hip and knee, using a manual goniometer by means of the following tests: Straight Leg Raise Test (SLR), Passive Hip Flexion Test (PHFT) and Modified Knee Extension Test (MKET), (2) intervention: stretching with different runtimes, (3) post-test: reappraisal of flexibility, conducted immediately after the intervention.
  
  
  RESULTS
  Significant difference was observed intra groups, group that did stretching exercises lasting 30 seconds (G30) (SLR p = 0.000. PHFT p = 0.003 and MKET p = 0.000) and group that did stretching exercises lasting 60 seconds (G60) (SLR p = 0.000. PHFT p = 0.001 and MKET p = 0.002). Comparing the groups, no significant difference was found (SLR p = 0.307; PHFT p = 0.904; MKET p = 0.132).
  
  
  CONCLUSIONS
  Thus it can be inferred that 30 seconds are sufficient for increased flexibility of young women. Therefore the time-treatment sessions can be optimized. Only the acute effect of stretching was observed; further investigation of the long-term effect is required.
authors.forename: Anelize
authors.initials: A
authors.lastname: Cini
authors.forename: Gabriela Souza
authors.initials: GS
authors.lastname: de Vasconcelos
authors.forename: Claudia Silveira
authors.initials: CS
authors.lastname: Lima
mesh_terms: D000328:Adult; D005260:Female; D000070633:Hamstring Muscles / Q000502:physiology*; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D052580:Muscle Stretching Exercises; D011187:Posture / Q000502:physiology; D016059:Range of Motion, Articular / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult
keywords: Lower extremity; muscle stretching exercises; range of motion; rehabilitation