title: Hamstring-and-Lower-Back Flexibility in Male Amateur Soccer Players.
abstract: OBJECTIVE
  This study investigated the hamstring-and-lower-back flexibility (HLBF) of male adult amateur soccer players, using the sit-and-reach test (SRT), with a view to obtaining population-based reference values and to determining whether SRT scores are associated with player characteristics.
  
  
  METHODS
  Cross-sectional cohort study.
  
  
  METHODS
  Teams from high-level Dutch amateur soccer competitions were recruited for participation.
  
  
  METHODS
  Dutch male high-level amateur field soccer players (n = 449) of age 18 to 40 years. Players with a hamstring injury at the moment of SRT-measurement or any other injury that prevented them from following the SRT protocol were excluded.
  
  
  METHODS
  Sit-and-reach test scores were measured and then population-based reference values were calculated as follows: >2SD below mean (defining "very low" HLBF), 1SD-2SD below mean ("low" HLBF), 1SD below mean to 1SD above mean ("normal" HLBF), 1SD-2SD above mean ("high" HLBF), and >2SD above mean ("very high" HLBF). Whether SRT scores were correlated with player characteristics was determined using a Pearson correlation coefficient or Spearman rho.
  
  
  RESULTS
  Sit-and-reach test scores ranged from 0 to 43.5 cm (mean 22.0 cm, SD 9.2). The cutoff points for population-based reference values were <3.5 cm for "very low", 3.5 to 13.0 cm for "low", 13.0 to 31.0 cm for "normal", 31.0 to 40.5 cm for "high", and >40.5 cm for "very high". Sit-and-reach test scores were significantly associated with players' height (ρ = -0.132, P = 0.005), body mass index (r = 0.114, P = 0.016), and history of anterior cruciate ligament surgery (P < 0.001).
  
  
  CONCLUSIONS
  This study is the first to describe the HLBF of amateur soccer players. The SRT reference values with cutoff points may facilitate evidence-based decision making regarding HLBF, and the SRT might be a useful tool to assess injury risk, performance, or for diagnostic purposes.
authors.affiliation: Department of Rehabilitation, Nursing Science & Sports, Rudolf Magnus Institute of Neurosciences, University Medical Center Utrecht, the Netherlands.
authors.forename: Nick
authors.initials: N
authors.lastname: van der Horst
authors.forename: Annique
authors.initials: A
authors.lastname: Priesterbach
authors.forename: Frank
authors.initials: F
authors.lastname: Backx
authors.forename: Dirk-Wouter
authors.initials: DW
authors.lastname: Smits
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D000070633:Hamstring Muscles / Q000502:physiology*; D006801:Humans; D008159:Lumbar Vertebrae / Q000502:physiology*; D008297:Male; D016059:Range of Motion, Articular; D012916:Soccer / Q000502:physiology*; D055815:Young Adult