title: The SpeedCourt: Reliability, Usefulness, and Validity of a New Method to Determine Change-of-Direction Speed.
abstract: OBJECTIVE
  To determine the reliability, usefulness, and validity of 3 different change-of-direction tests on a SpeedCourt (SC(CODT)) in team-sport players.
  
  
  METHODS
  For reliability and usefulness, 30 players (16 female and 14 male; age 19 ± 3 y, height 169 ± 30 cm, body mass 70 ± 11 kg) performed 3 SC(CODT)s differing in duration (7-45 s) on 3 occasions 1 wk apart. The total sprint times (TT) and time to change direction (TCD) were analyzed for each SC(CODT). For validity, 14 players performed the Illinois Agility Test (IAT) and 505 test on a separate occasion.
  
  
  RESULTS
  TT for all SC(CODT)s is reliable (ICC > .79, CV < 5%), useful (TE < SWC0.5), and valid (IAT r > .71, P < .05; 505 test r > .54, P < .05). SC(CODT) variable TCD may be useful (TE = SWC0.5) but shows limited reliability with ICC >.65 and a CV >5%.
  
  
  CONCLUSIONS
  All SC(CODT)s are reliable, useful, and valid to detect moderate performance changes regarding TT, with limited reliability for TCD. The quality of assessment improves when players are well familiarized with the SC(CODT).
authors.affiliation: Inst for Sport Sciences, Julius-Maximilians University Würzburg, Würzburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Düking
authors.forename: Dennis-Peter
authors.initials: DP
authors.lastname: Born
authors.forename: Billy
authors.initials: B
authors.lastname: Sperlich
mesh_terms: D000293:Adolescent; D054874:Athletic Performance / Q000502:physiology*; D005080:Exercise Test / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D015203:Reproducibility of Results; D055815:Young Adult