title: Predictors of Repeated High-Intensity-Effort Ability in Rugby League Players.
abstract: OBJECTIVE
  To investigate the relationship between repeated high-intensity-effort (RHIE) ability and selected physical qualities in rugby league players.
  
  
  METHODS
  Sixteen rugby league players underwent measurements of upper-body strength (4-repetitionmaximum [4RM] bench press, weighted chin-up, weighted dips), upper-body muscle endurance (body-mass maximum-repetition chin-up, body-mass maximum-repetition dips), lower-body strength (4RM squat), estimated maximal aerobic power (multistage fitness test), and RHIE ability. The RHIE-ability test consisted of 1 × 10-m sprint, 3 × full-contact 1-on-1 tackling efforts, and a 30-m jog recovery. Players performed 4 repetitions of the test, with each repetition completed in 40 second. During the RHIE test, player speed was evaluated with a 10-m sprint effort while the movement of players was recorded using a wearable micro-technology device. 2D Player Load was used to quantify the collision component of the test.
  
  
  RESULTS
  Speed decrement was lower for the first- (-2.4% ± 1.0%) than the second-grade (-4.7% ± 2.1%) players. Players with greater initial speed had a higher average speed over the 4 sprints (r = .75), while players with greater maximum-repetition dips maintained a higher 2D Player Load (r = .76).
  
  
  CONCLUSIONS
  These findings demonstrate a relationship between well-developed acceleration and upper-body muscle-endurance qualities and RHIE ability in rugby league players. Training programs designed to develop acceleration and upper-body muscle endurance are likely to improve RHIE ability.
authors.affiliation: School of Exercise Science, Australian Catholic University, Brisbane, Australia.
authors.forename: Tim J
authors.initials: TJ
authors.lastname: Gabbett
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Wheeler
mesh_terms: D000054:Acceleration; D000328:Adult; D056352:Athletes / Q000523:psychology; D054874:Athletic Performance / Q000523:psychology; D001696:Biomechanical Phenomena; D003163:Competitive Behavior; D005080:Exercise Test; D005538:Football / Q000523:psychology; D040362:Geographic Information Systems; D006801:Humans; D008297:Male; D009043:Motor Activity; D018763:Muscle Fatigue; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000502:physiology*; D010807:Physical Endurance; D020127:Recovery of Function; D012420:Running; D013647:Task Performance and Analysis; D013997:Time Factors; D055815:Young Adult