title: Intrarater reliability of neck strength measurement of rugby union players using a handheld dynamometer.
abstract: OBJECTIVE
  The purpose of this study was to investigate the isometric neck strength profiles of rugby union players and to assess the intrarater reliability of isometric neck strength measurement using a handheld dynamometer.
  
  
  METHODS
  Twenty-five male, academy-level, rugby union players (forwards [n = 16], backs [n = 9]) were tested on 2 occasions during a training week 2 days apart. Isometric strength of the neck musculature was tested using a handheld dynamometer, for flexion (F), extension (E), left side flexion (LSF), and right side flexion (RSF). The average of 3 trials for each test position was used for statistical analysis. The following isometric neck strength values were obtained: F, E, F:E, LSF, RSF, LSF:RSF, and total isometric strength.
  
  
  RESULTS
  Intrarater reliability intraclass correlation coefficients ranged from 0.80 to 0.92 (intraclass correlation coefficient values: F, 0.85; E, 0.85; F:E, 0.85; LSF, 0.80; RSF, 0.85; LSF:RSF, 0.91; total isometric strength, 0.92), thus indicating excellent reliability in all instances. Forwards recorded significantly greater E scores compared with backs (637.10 ± 75.15 N vs 537.87 ± 82.25 N). Forwards also recoded significantly greater total isometric neck strength scores (2151.96 ± 231.11 N vs 1814.21 ± 211.26 N).
  
  
  CONCLUSIONS
  The results of this study provide isometric neck strength values for the forward and back units in the rugby union and indicate that a handheld dynamometer may be a reliable tool for assessing isometric neck strength in this population.
authors.affiliation: Strength and Conditioning Coach, Ulster Rugby, Belfast, Northern Ireland.
authors.forename: Kevin
authors.initials: K
authors.lastname: Geary
authors.forename: Brian S
authors.initials: BS
authors.lastname: Green
authors.forename: Eamonn
authors.initials: E
authors.lastname: Delahunt
mesh_terms: D001265:Athletic Injuries / Q000517:prevention & control; D005538:Football / Q000502:physiology*; D006225:Hand; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D009334:Neck Muscles / Q000502:physiology*; D015588:Observer Variation; D015203:Reproducibility of Results; D012494:Sampling Studies; D055815:Young Adult
keywords: Isometric Contraction; Neck; Rehabilitation; Spine