• Influence of Knowledge of Task Endpoint on Pacing and Performance During Simulated Rugby League Match Play

      Mullen, Thomas; Twist, Craig; Highton, Jamie M.; University of Chester (Human Kinetics, 2017-10-31)
      Purpose: To examine the influence of knowledge of exercise duration on pacing and performance during simulated rugby league match play. Methods: Thirteen male university rugby players completed 3 simulated rugby league matches (RLMSP-i) on separate days in a random order. In a control trial, participants were informed that they would be performing 2 × 23-min bouts (separated by 20 min) of the RLMSP-i (CON). In a second trial, participants were informed that they would be performing 1 × 23-min bout of the protocol but were then asked to perform another 23-min bout (DEC). In a third trial, participants were not informed of the exercise duration and performed 2 × 23-min bouts (UN). Results: Distance covered and high-intensity running were higher in CON (4813 ± 167 m, 26 ± 4.1 m/min) than DEC (4764 ± 112 m, 25.2 ± 2.8 m/min) and UN (4744 ± 131 m, 24.4 m/min). Compared with CON, high-intensity running and peak speed were typically higher for DEC in bout 1 and lower in bout 2 of the RLMSP-i, while UN was generally lower throughout. Similarly, DEC resulted in an increased heart rate, blood lactate, and rating of perceived exertion than CON in bout 1, whereas these variables were lower throughout the protocol in UN. Conclusions: Pacing and performance during simulated rugby league match play depend on an accurate understanding of the exercise endpoint. Applied practitioners should consider informing players of their likely exercise duration to maximize running.
    • The reliability of tests for sport-specific skill amongst elite youth rugby league players

      Waldron, Mark; Worsfold, Paul R.; Twist, Craig; Lamb, Kevin L.; University of Chester (Taylor & Francis, 2012-08-10)
      In rugby league, tests of sport-specific skill often involve subjective assessments of performance by observers of varying qualification. However, the reliability of such subjective assessments has yet to be investigated via appropriate statistical techniques. Therefore, the aims of the current study were to investigate: (1) the intra-observer reliability of a non-qualified observer (‘novice’) and (2) the inter-observer reliability of the three observers (two qualified ‘experts’ and one novice observer) in the assessment of catching, passing and tackling (stages 1 and 2) ability in elite adolescent rugby league players (age: 14.790.5 years). Players performed each skill element within a simulated practice drill and were assessed in ‘real time’ by the observers according to pre-defined criteria. An overall bias (PB0.05) was revealed between the observers in stage 1 of catching and stage 1 of passing, the differences being higher for the novice compared to both expert coaches for each stage of catching and the first stage of passing, and between expert 2 and the novice for stage 2 of tackling. No comparisons met the pre-determined analytical goal of ‘perfect agreement’, for any of the skill components. Comparisons between the expert observers did not reach perfect agreement, with the lowest values occurring for both tackling skill stages (60 65%). None of the tests employed were sufficiently reliable to potentially discern between players of differing ability, which may mean up to 56% of players’ skill being misinterpreted. The credibility of such assessments should be questioned and alternative tests considered.
    • Transient fatigue is not influenced by ball-in-play time during elite rugby league matches

      Waldron, Mark; Highton, Jamie M.; Thomson, Edward; Twist, Craig; St Mary's University; University of New England; University of Chester (Lippincott, Williams & Wilkins, 2017-03-13)
      The capacity to sustain high-speed running is important for rugby league players. Transient fatigue, described as a reduction in high-speed running in the 5-min after a peak 5-min period, is a phenomenon observed during rugby league matches. This concept has recently been questioned based on the proposed confounding influence of ball-in-play time during these periods. Therefore, this study examined the changes in high-speed running (> 14 km∙h-1) of elite rugby league players, as well as ball-in-play time, during the peak, subsequent and mean 5-min periods of five competitive matches using 5 Hz GPS devices. The suitability of ball-in-play time as a covariate was also evaluated. The high-speed running and ball-in-play time was different between peak (26.7 ± 5.5 m∙min-1 and 177 ± 37 s) and subsequent (12.1 ± 6.2 m∙min-1 and 147 ± 37 s) 5-min periods (P < 0.05; most likely ↓). However, there was no relationship (r = 0.01 to -0.13; P > 0.05) between ball-in-play time and high-speed running and ball-in-play time was not independent of the match period. This study has reaffirmed the presence of transient fatigue during elite rugby league matches but questioned the influence of ball-in-play time as a confounding factor. These observations have implications for the design of appropriate training practices and informing tactical strategies employed by coaches. Most importantly, any practitioner wishing to measure transient fatigue could follow a similar statistical approach taken herein and, based on the current findings would not need to account for ball-in-play time as a confounding variable.
    • Validity of a portable jump mat for assessing countermovement jump performance in elite rugby league players

      Dobbin, Nicholas; Hunwicks, Richard; Highton, Jamie M.; Twist, Craig; University of Chester; Rugby Football League, Leeds (Thieme Publishing, 2016-12-08)
      Validity of a portable jump mat for assessing countermovement jump performance in elite rugby league players