title: Influence of physical contact on pacing strategies during game-based activities.
abstract: OBJECTIVE
  Repeated sprinting incorporating tackles leads to greater reductions in sprint performance than repeated sprinting alone. However, the influence of physical contact on the running demands of game-based activities is unknown. The aim of this study was to determine whether the addition of physical contact altered pacing strategies during game-based activities.
  
  
  METHODS
  Twenty-three elite youth rugby league players were divided into 2 groups. Group 1 played the contact game on day 1 while group 2 played the noncontact game; 72 h later they played the alternate game. Each game consisted of offside touch on a 30 × 70-m field, played over two 8-min halves. Rules were identical between games except the contact game included a 10-s wrestle bout every 50 s. Microtechnology devices were used to analyze player movements.
  
  
  RESULTS
  There were greater average reductions during the contact game for distance (25%, 38 m/min, vs 10%, 20 m/min; effect size [ES] = 1.78 ± 1.02) and low-speed distance (21%, 24 m/min, vs 0%, 2 m/s; ES = 1.38 ± 1.02) compared with the noncontact game. There were similar reductions in high-speed running (41%, 18 m/min, vs 45%, 15 m/min; ES = 0.15 ± 0.95).
  
  
  CONCLUSIONS
  The addition of contact to game-based activities causes players to reduce low-speed activity in an attempt to maintain high-intensity activities. Despite this, players were unable to maintain high-speed running while performing contact efforts. Improving a player's ability to perform contact efforts while maintaining running performance should be a focus in rugby league training.
authors.affiliation: School of Exercise Science, Australian Catholic University, Brisbane, QLD, Australia.
authors.forename: Rich D
authors.initials: RD
authors.lastname: Johnston
authors.forename: Tim J
authors.initials: TJ
authors.lastname: Gabbett
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Seibold
authors.forename: David G
authors.initials: DG
authors.lastname: Jenkins
mesh_terms: D000293:Adolescent; D003163:Competitive Behavior; D018592:Cross-Over Studies; D004867:Equipment Design; D005538:Football; D040362:Geographic Information Systems / Q000295:instrumentation; D006801:Humans; D055616:Microtechnology / Q000295:instrumentation; D009043:Motor Activity; D010807:Physical Endurance; D012420:Running; D013647:Task Performance and Analysis; D013997:Time Factors; D055815:Young Adult