title: Influence of field position and phase of play on the physical demands of match-play in professional rugby league forwards.
abstract: OBJECTIVE
  No study has investigated the influence of field position and phase of play on the physical demands of match-play in professional rugby league forwards. We investigated the physical demands placed on forwards in elite rugby league matches, with special reference to how these demands differed between attack and defence, and in different field positions.
  
  
  METHODS
  Cohort study.
  
  
  METHODS
  Twenty-two rugby league players (26 ± 3 years) from the same professional club participated in this study. Global positioning system (GPS) analysis was completed during 23 matches. Video footage was synchronised with the GPS files and coded for the time spent in attack and defence, and in one of three different field positions (0-30 m, 31-70 m, 71-100 m).
  
  
  RESULTS
  The physical demands of defence were consistently greater than attack. Moderate to large differences (ES=0.62-1.41) were found between defence and attack for distance covered (109 ± 16 m/min vs. 82 ± 12 m/min), low speed distance (104 ± 15 m/min vs. 78 ± 11 m/min), frequency of collisions (1.9 ± 0.7/min vs. 0.8 ± 0.3/min), and repeated high-intensity effort bouts (1 every 4.9 ± 5.1 min vs. 1 every 9.4 ± 6.1 min). The running demands and frequency of repeated high-intensity effort bouts were greater when defending in the opposition's 30 m zone (i.e. 71-100 m), with repeated high-intensity effort bouts also occurring more frequently when defending the team's own try-line and when attacking the opposition's try-line.
  
  
  CONCLUSIONS
  Specific training drills designed to replicate the attacking and defensive demands of different field positional zones are likely to be effective in preparing players for the most demanding activities that occur in professional rugby league match-play.
authors.affiliation: School of Exercise Science, Australian Catholic University, Brisbane, Australia. Electronic address: tim_gabbett@yahoo.com.au.
authors.forename: Tim J
authors.initials: TJ
authors.lastname: Gabbett
authors.affiliation: School of Exercise Science, Australian Catholic University, Melbourne, Australia.
authors.forename: Chris
authors.initials: C
authors.lastname: Polley
authors.affiliation: School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia.
authors.forename: Dan B
authors.initials: DB
authors.lastname: Dwyer
authors.affiliation: St. Kilda Football Club, Melbourne, Australia.
authors.forename: Simon
authors.initials: S
authors.lastname: Kearney
authors.affiliation: Melbourne Storm Rugby League Club, Melbourne, Australia.
authors.forename: Alex
authors.initials: A
authors.lastname: Corvo
mesh_terms: D000328:Adult; D003163:Competitive Behavior; D005538:Football / Q000502:physiology*; D040362:Geographic Information Systems; D006801:Humans; D010807:Physical Endurance / Q000502:physiology; D012420:Running / Q000502:physiology*; D014741:Video Recording
keywords: Activity profiles; Repeated-effort; Team sports; Time-motion analysis; Training