title: Critical factors for the prevention of low back pain in elite junior divers.
abstract: OBJECTIVE
  During competitive diving, divers jump up from 1 to 3 m springboards or 5 to 10 m platforms and dive into the water. The impact forces are very large in the water entry phase, and, as such, microtraumatic injuries are common due to the tremendous physical stress placed on the diver. Low-back pain (LBP) is the most frequently reported symptom in divers. This study aimed to extract possible risk factors related to LBP from physical and technical characteristics in Japanese elite junior divers.
  
  
  METHODS
  Eighty-three elite junior divers (42 men and 41 women) in Japan were included in this study. LBP was assessed by a questionnaire, interview and physical examination during a national training camp. Morphological data, physical fitness and diving skills were also evaluated. The factors related to LBP were extracted by using logistic-regression analysis and the forward-selection method (likelihood ratio).
  
  
  RESULTS
  A total of 37.3% (31 reports) of back pain occurred in the lumbar region. Shoulder flexibility (OR 0.919; 95% CI 0.851 to 0.992) and age (OR 0.441; 95% CI 0.239 to 0.814) were recognised as factors related to LBP in male-elite junior divers, whereas only age (OR 0.536; 95% CI 0.335 to 0.856) was a factor in female-elite junior divers.
  
  
  CONCLUSIONS
  Our results suggest that shoulder flexibility is important for preventing LBP in elite-male junior divers, since they require full shoulder flexion during the water entry phase. Limited shoulder flexibility could cause lumbar hyperextension when adjusting for the angle of water entry.
authors.affiliation: Department of Physical Therapy, Health Science University, , Fujikawaguchiko-Town, Japan.
authors.forename: Takaya
authors.initials: T
authors.lastname: Narita
authors.forename: Koji
authors.initials: K
authors.lastname: Kaneoka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Takemura
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Sakata
authors.forename: Takamichi
authors.initials: T
authors.lastname: Nomura
authors.forename: Shumpei
authors.initials: S
authors.lastname: Miyakawa
mesh_terms: D000293:Adolescent; D004242:Diving / Q000009:adverse effects* / Q000502:physiology; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology / Q000517:prevention & control*; D008297:Male; D009068:Movement / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology; D011187:Posture / Q000502:physiology; D012307:Risk Factors; D012785:Shoulder Joint / Q000502:physiology; D013312:Stress, Physiological / Q000502:physiology
keywords: Adolescents; Back injuries; Shoulder injuries; Swimming