title: Muscle flexibility as a risk factor for developing muscle injuries in male professional soccer players. A prospective study.
abstract: BACKGROUND
  Muscular tightness is frequently postulated as an intrinsic risk factor for the development of a muscle injury. However, very little prospective data exist to prove this.
  
  
  OBJECTIVE
  Increased muscle tightness identifies a soccer player at risk for a subsequent musculoskeletal lesion.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  We examined 146 male professional soccer players before the 1999-2000 Belgian soccer competition. None of the players had a history of muscle injury in the lower extremities in the previous 2 years. The flexibility of the hamstring, quadriceps, adductor, and calf muscles of these players was measured goniometrically before the start of the season. All of the examined players were monitored throughout the season to register subsequent injuries.
  
  
  RESULTS
  Players with a hamstring (N = 31) or quadriceps (N = 13) muscle injury were found to have significantly lower flexibility in these muscles before their injury compared with the uninjured group. No significant differences in muscle flexibility were found between players who sustained an adductor muscle injury (N = 13) or a calf muscle injury (N = 10) and the uninjured group.
  
  
  CONCLUSIONS
  These results indicate that soccer players with an increased tightness of the hamstring or quadriceps muscles have a statistically higher risk for a subsequent musculoskeletal lesion.
  
  
  CONCLUSIONS
  Preseason hamstring and quadriceps muscle flexibility testing can identify male soccer players at risk of developing hamstring and quadriceps muscle injuries.
authors.affiliation: Department of Rehabilitation Sciences and Physical Therapy, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium.
authors.forename: Erik
authors.initials: E
authors.lastname: Witvrouw
authors.forename: Lieven
authors.initials: L
authors.lastname: Danneels
authors.forename: Peter
authors.initials: P
authors.lastname: Asselman
authors.forename: Thomas
authors.initials: T
authors.lastname: D'Have
authors.forename: Dirk
authors.initials: D
authors.lastname: Cambier
mesh_terms: D001265:Athletic Injuries / Q000503:physiopathology*; D016009:Chi-Square Distribution; D006801:Humans; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D009129:Muscle Tonus / Q000502:physiology*; D018482:Muscle, Skeletal / Q000293:injuries*; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012916:Soccer; D013848:Thigh / Q000503:physiopathology