• Changes in anthropometry and performance, and their inter-relationships, across three seasons in elite youth rugby league players

      Waldron, Mark; Worsfold, Paul R.; Twist, Craig; Lamb, Kevin L.; University of New England, Australia ; University of Chester ; University of Chester ; University of Chester (Lippincott, Williams & Wilkins, 2014-11-30)
      This study investigated changes in anthropometry and performance, and their inter-relationships, across three consecutive seasons (under-15 to under-17 age group) in elite youth rugby league players. Each player took part in annual anthropometrical and performance assessments, comprising measurements of stature; body mass; limb lengths and circumference; skinfolds, predicted muscle cross-sectional area (CSA); 20 m speed, counter-movement jump height, vertical power and aerobic power. Lean body mass % changed (P < 0.05) between the under-15 (70.9 ± 5.9 %), under-16 (72.0 ± 5.8 %) and the under-17 age groups (74.1 ± 5.7 %). Likewise, predicted quadriceps muscle cross-sectional area (CSA) also changed (P < 0.05) between each age group (under-15 = 120.9 ± 37.8 cm2; under-16 = 133.2 ± 36.0 cm2; under-17 = 154.8 ± 28.3 cm2). Concomitant changes between the under-15 and under-16 group were found for 20 m speed (3.5 ± 0.1 cf. 3.4 ± 0.2 s; P = 0.008) and predicted jumping power (3611.3 ± 327.3 W cf. 4081.5 ± 453.9 W; P = 0.003). Both lean body mass and quadriceps muscle CSA consistently, related to both 20 m sprint time and jumping power, with r-values ranging between -0.39 to –0.63 (20 m sprint time) and 0.55 to 0.75 (jumping power). Our findings demonstrate the importance of gains in lean body mass across later-adolescence that support the ability to generate horizontal speed and predicted vertical power. This information should inform the expectations and subsequent training programs of elite rugby league practitioners.
    • Coach behaviour analysis within elite youth soccer

      Worsfold, Paul R.; University of Chester (Routledge, 2013-07-23)
      Soccer clubs recruit talented youth players into their development programmes with the aim of nurturing their ability, and ultimately to develop them into professional soccer players (Carling et al. 2012). Past talent identification and development research has identified that youth players, who are then selected to play at higher standards of competition, possess greater endurance capacity (Gil et al. 2007; Reilly et al. 2000), faster sprinting performance (Le Gall et al. 2010), have faster dribbling performance (Huijgen et al. 2009) and are generally more physically advanced in comparison to players of lower ability (Gravina et al. 2008). In contrast to traditional measures, few studies have considered player development in relation to coach-player interaction. There is general agreement that coaching is a process that primarily focuses on aiding athletes in achieving their peak performance (Woodman, 1993). Therefore, the way in which a coach facilitates learning through their words and actions, which is the core principal of the coach’s instructional behavior, can strongly impact upon an athletes’ performance and progression, as well as their emotional well-being (Miller, 1992). Promoting a mastery climate, with equal opportunities and support for athletes fosters group cohesion and reduces performance anxiety through the reduction of social pressures (Smith et al. 2007). Despite the need for equality to promote team cohesion throughout the team, differentiation between feedback provided to effective and non-effective team sport players has previously been identified. In many team sports, it has been suggested that coaches observe and interact more with effective players (based upon match time), provide more feedback (instructional, positive, and negative), and give more positive evaluations within training sessions when compared to non-effective players (Markland & Martinek, 1988; Wang et al. 2001; Rosado & Mesquita, 2009). To date no research has conducted a longitudinal assessment focusing on talent development and player progression through coach behaviour analysis within elite youth soccer. Therefore, the aim of the study was to objectively analyse coaching behaviour within three playing squads at an elite level soccer club during two competitive seasons.
    • Coaches’ philosophies on the transfer of strength training to elite sports performance

      Burnie, Louise; Barratt, Paul; Davids, Keith; Stone, Joseph; Worsfold, Paul R.; Wheat, Jon; Sheffield Hallam University; English Institute of Sport; University of Chester (Sage, 2017-12-07)
      The objective of the study was to explore coaches’ philosophies regarding strength training (repetitive muscle actions against high loads) and the transfer of strength training to sports performance. Thirteen world class coaches and athletes from track cycling, BMX, sprint kayaking, rowing and athletics sprinting were interviewed using an open-ended, semi-structured approach. Participants were asked about their coaching philosophies, design of athlete training programmes, strength training and its transfer to sports performance. A thematic analysis was conducted. Data trustworthiness was enhanced by methods of member checking and analyst triangulation. Coaches believed that task-specific strength is essential for sports performance. They reported that non-specific strength training (“traditional” gym-based strength exercises that are not specific to a sport movement) is important for increasing athletes’ muscle size and strength. This is typically used in conjunction with resisted sport movement training (for example, increased resistance running, pedalling or rowing), believed to achieve an effective transfer of enhanced muscle strength to sports performance. Coaches described the transfer process as complex, with factors associated with fatigue and coordination having particular significance. The importance that coaches place on coordination is supported by a theoretical model that demonstrates increases in muscle strength from strength training may need to be accompanied with a change in inter-muscular coordination to improve sport performance. The idea that each athlete needs to adapt intermuscular coordination in response to a change in his/her unique set of “organism constraints” (e.g. muscle strength) is well described by the theory of ecological dynamics and Newell’s model of constraints.
    • The influences of rugby spin pass technique on movement time, ball velocity and passing accuracy

      Worsfold, Paul R.; Page, Matthew; University of Chester (University of Wales Institute, Cardiff, 2014-04)
      The success of a rugby spin pass is determined by the speed of the passing movement and the resultant velocity, distance and accuracy of the ball flight. The present study investigated 900 dominant and 900 non-dominant hand spin passes at three randomised target distances (4, 8 and 12 m), whilst players ran between 60 and 80% of their maximum speed. Two distinct types of spin pass technique were compared. One involved the player lowering their body height (‘body drop’) then raising it again prior to ball release, and the other, players maintained a more upright body position and incorporated greater arm movement. The current study assessed performance measures (velocity, spin, timing, accuracy) of the two previously identified passing techniques made from the players’ dominant and non-dominant hands. The percentage of passes which included a ‘body drop’ phase rose linearly with pass distance. The ‘body drop’ technique resulted in higher ball velocities and improved accuracy from both the dominant and non-dominant passing hands. In comparison, the more upright passing technique resulted in a faster passing movement, but was compromised by lower ball velocity and accuracy. The findings provide an understanding of how different spin pass techniques affect the mechanics of ball flight and performance.
    • Measurement procedures affect the interpretation of metatarsophalangeal joint function during accelerated sprinting

      Smith, Grace; Lake, Mark; Lees, Adrian; Worsfold, Paul R.; University of Chester ; Liverpool John Moores University ; Liverpool John Moores University ; University of Chester (Routledge, 2012-08-07)
      The metatarsophalangeal joint (MPJ) is a significant absorber of energy in sprinting. This study examined the influence of MPJ axis choice and filter cut-off frequency on kinetic variables describing MPJ function during accelerated sprinting. Eight trained sprinters performed maximal sprints along a runway. Three dimensional high-speed (1000 Hz) kinematic and kinetic data were collected at the 20 m point. Three axis definitions for the five MPJs were compared. MPJ moments, powers and energies were calculated using different filter cut-off frequencies. The more anatomically appropriate dual axis resulted in less energy absorbed at the MPJ compared to the oblique axis which also absorbed less energy compared to the perpendicular axis. Furthermore, a low cut-off frequency (8 Hz) substantially underestimated MPJ kinematics, kinetics and the energy absorbed at the joint and lowered the estimate of energy production during push-off. It is concluded that a better understanding of MPJ function during sprinting would be obtained by using an oblique or anatomically appropriate representation of the joint together with appropriate kinematic data sampling and filtering so that high frequency movement characteristics are retained.
    • The observational analysis of elite coaches within youth soccer: The importance of performance analysis

      Nicolls, Scott B.; Worsfold, Paul R.; University of Chester; Middlesex University; Manchester Institute of Health and Performance (SAGE, 2016-11-15)
      The study investigated the observational capabilities of experienced elite coaches whilst focusing upon soccer specific actions and playing positions within elite youth soccer. Six soccer coaches assessed the performances of 10 youth soccer players (across 8 matches) on their short/long passing, tackling, shooting, heading and dribbling. Analysis was undertaken on an overall, quality and positional grouping basis. Mean observational accuracy was 38.8%, with successful shooting (78.6%) and passing (29.9%) illustrating the range. The limited effective observation of dribbling (37.2%), often considered a separating factor within talent identification, highlights the need for objective measures to aid such processes. Positional grouping analysis elicited 20% more effective observation for unsuccessful compared with successful actions. The poor level of observational accuracy identified herein has significant implications on talent identification assessments devoid of post-performance analyses. The findings reinforce the importance of performance analysis in the provision of highly accurate and comprehensive augmented feedback within the coaching process.
    • The relationship between physical abilities, ball-carrying and tackling among elite youth rugby league players

      Waldron, Mark; Worsfold, Paul R.; Twist, Craig; Lamb, Kevin L.; University of Chester (Taylor & Francis, 2013-09-27)
      This study investigated the relationship between the physical abilities of adolescent rugby league players and tackling and ball-carrying skills performed during matches, across three seasons (under-15 to under-17). The players were measured each season for acceleration (10–30 m), peak and mean speed (10–30 m), sprinting force (10–30 m), aerobic power, counter-movement jump (CMJ) height and jumping power. The matches were filmed and analysed for ball-carrying and tackling frequency per minute (successful and unsuccessful outcomes). There were strong relationships between successful carries∙min–1 and 10 m force in the under-15 (R = 0.61, P < 0.001), under-16 (R = 0.69, P < 0.001) and under-17 groups (R = 0.64, P < 0.001). There were also strong and moderate relationships between predicted vertical power and successful carries∙min–1 in the under-15 (R = 0.63, P = 0.011) and under-17 group (R = 0.40, P = 0.030), respectively. There were no relationships between carries or tackles and any other performance indicators. These findings suggest that acceleration, in accordance with gains in body mass, support ball-carrying but not tackling performance. Performance measurements, such as CMJ or aerobic power, do not support ball-carrying ability among youth rugby league players.
    • The reliability of Functional Movement Screening (FMS) and in-season changes in physical function and performance among elite rugby league players

      Waldron, Mark; Gray, Adrian; Worsfold, Paul R.; Twist, Craig; University of New England, Australia ; University of New England, Australia ; University of Chester ; University of Chester (Lippincott, Williams & Wilkins, 2014-03-26)
      Functional Movement Screening (FMS) comprises seven tests that assess fundamental movement characteristics of athletes. However, the reliability of the FMS protocol and its sensitivity to changes in physical performance has not been appropriately investigated. Accordingly, this study aimed to assess the real-time reliability of the FMS protocol and to establish changes in both FMS and tests of physical performance throughout a season. The reliability of the FMS components (12 in total) were assessed via a non-parametric statistical approach, based on two trials, separated by one week. Score on the FMS, strength (3 RM full squat, 1 RM bench press), running speed (10 & 40 m) and jump height of 12 elite male under-19 rugby league players was monitored at pre-, mid- and late-season periods. There was no bias found between trials for the FMS, with the majority of components reaching 100% ‘perfect agreement’. There were no effects of season stage on any of the FMS components; however, an improvement in every performance test was apparent between the pre- and both mid- and late-season periods. Our findings demonstrate that the FMS can be reliably administered to elite rugby league players but question its sensitivity to systematic changes in athletic performance.
    • 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.
    • Swarming behaviour in elite race bunch cycling: a case study

      Waldron, Mark; Worsfold, Paul R.; White, Christopher; Murray, Stafford; University of Chester (Cardiff Metropolitan University, 2011-04)
      The current study undertook a dynamical systems analysis of race bunch cycling, considering the 'sports contest' as a dynamical, self organising system (McGarry et al., 2002). Data from one international track racing event was used to analyse a potential non-linear aggregation theory of 'swarming' in the 'points race', with two objectives; 1) To identify a race profile of a basic swarm mentality within the points race; 2) To identify system stability and the possible perturbation of stability in relation to successful and unsuccessful breakaways. Stability was based upon a 'normal' profile of race behaviours, measured by three separate dependent measures, namely; Absolute Difference, Rate of Change and Phase Duration. Results showed; 1) The points race exhibits the quintessential 'attract and repel' elements that characterise the swarm mentality 2) One-way ANOVA revealed that breakaways of both successful (3.3±1.2 half laps) and unsuccessful (3.1±1.5 half laps) conditions tend to differ from the race 'norm' (2.1±1.3 half laps) in terms of phase duration (F(2, 228)=18.4, P<0.05), suggesting that breakaways perturb the system through longer attract and repel phases. Results are discussed in relation to the current and future effectiveness of describing race bunch cycling as a dynamical system.
    • The importance of perturbations in elite squash: An analysis of their ability to successfully predict rally outcome

      Roddy, Ryan; Lamb, Kevin L.; Worsfold, Paul R.; University of Chester (University of Wales Institute, Cardiff, 2014-12)
      This study investigated the presence of perturbations within elite squash through the analysis of critical incidents responsible for successful rally outcome.
    • A three-season comparison of match performances among selected and unselected elite youth rugby league players

      Waldron, Mark; Worsfold, Paul R.; Twist, Craig; Lamb, Kevin L.; University of New England, Australia; University of Chester (Taylor & Francis, 2014-02-28)
      This study compared technical actions, movements, heart rates and perceptual responses of selected and unselected youth rugby league players during matches (under-15 to under-17). The players’ movements and heart rates were assessed using 5 Hz Global Positioning Systems (GPS), while their technical actions were analysed using video analysis. The maturity of each player was predicted before each season for statistical control. There were no differences (P > 0.05) between selected and unselected players in the under-15 or the under-17 age groups for any variables. However, in the under-16 group, the selected players (57.1 ± 11.9 min) played for longer than the unselected players (44.1 ± 12.3 min; P = 0.017; ES = 1.08 ± CI = 0.87), and covered more distance (5,181.0 ± 1063.5 m cf. 3942.6 ± 1,108.6m, respectively; P = 0.012; ES = 1.14 ± CI = 0.88) and high intensity distance (1,808.8 ± 369.3 m cf. 1,380.5 ± 367.7 m, respectively; P = 0.011; ES = 1.16 ± CI = 0.88). Although successful carries per minute was higher in the selected under-15 group, there were no other differences (P > 0.05) in match performance relative to playing minutes between groups. Controlling for maturity, the less mature, unselected players from the under-16 group performed more high-intensity running (P < 0.05). Our findings question the use of match- related measurements in differentiating between selected and unselected players, showing that later maturing players were unselected, even when performing greater high-intensity running during matches.
    • Track cycling: An analysis of the pacing strategies employed during the devil elimination race

      Gill, Kevin; Worsfold, Paul R.; White, Christopher; University of Chester (Cardiff Metropolitan University, 2014-04-01)
      This study aimed to provide a description of the pacing requirements of the track cycling Elimination race, and to identify effective pacing strategies to maximise overall Omnium medal opportunity. Six male, and six female elite competitive races were investigated using half-lap split times. Selected dependant variables were; mean speed and variation in speed. Spearman’s Rho correlations were used to test patterns between dependant variables and the final finishing position of riders. One-way ANOVAs were also applied to test for differences in dependant variables, between successful (top 6 finishers) and unsuccessful groups (7th-12th). Pacing patterns of the men's and women's races were complex, but followed an overall positive and variable pacing pattern, with men's race quarter speeds of 52.8km/h (±1.9), 52.1km/h (±2.1), 51.1km/h (±2.2), and 49.5km/h (±5.5). In general, differences in pacing strategy were not found to significantly influence the success of riders unless employed late in the race. Results are discussed for the application and the development of effective elimination race strategies and tactics.