• Factors affecting the anthropometric and physical characteristics of elite academy rugby league players: a multi-club study.

      Dobbin, Nicholas; Moss, Samantha L.; Highton, Jamie M.; Twist, Craig; University of Chester (Human Kinetics, 2019-01-24)
      Purpose: To investigate the factors affecting the anthropometric and physical characteristics of elite academy rugby league players. Methods: One hundred and ninety-seven elite academy rugby league players (age = 17.3 ± 1.0 years) from five Super League clubs completed measures of anthropometric and physical characteristics during a competitive season. The interaction between, and influence of contextual factors on characteristics was assessed using linear mixed modelling. Results: Associations were observed between several anthropometric and physical characteristics. All physical characteristics improved during preseason and continued to improve until mid-season where thereafter 10 m sprint (η2 = 0.20 cf. 0.25), CMJ (η2 = 0.28 cf. 0.30) and prone Yo-Yo Intermittent Recovery Test (Yo-Yo IR) (η2 = 0.22 cf. 0.54) performance declined. Second (η2 = 0.17) and third (η2 = 0.16) years were heavier than first years, whilst third years had slower 10 m sprint times (η2 = 0.22). Large positional variability was observed for body mass, 20 m sprint time, medicine ball throw, countermovement jump, and prone Yo-Yo IR1. Compared to bottom-ranked teams, top demonstrated superior 20 m (η2 = -0.22) and prone Yo-Yo IR1 (η2 = 0.26) performance whilst middle-ranked teams reported higher CMJ height (η2 = 0.26) and prone Yo-Yo IR1 distance (η2 = 0.20), but slower 20 m sprint times (η2 = 0.20). Conclusion: These findings offer practitioners designing training programmes for academy rugby league players insight into the relationships between anthropometric and physical characteristics and how they are influenced by playing year, league ranking, position and season phase.
    • Fitness Monitoring in Elite Soccer Players: Group vs. Individual Analyses.

      Rabbani, Alireza; Kargarfard, Mehdi; Twist, Craig (2018-06-14)
      Rabbani, A, Kargarfard, M, and Twist, C. Fitness monitoring in elite soccer players; group vs. individual analyses. J Strength Cond Res XX(X): 000-000, 2018-The aims of this study were to (a) examine changes in group and individual HR measures during a submaximal warm-up test, and (b) investigate the relationship between accumulated internal training loads and HR changes during an in-season phase among elite soccer players (n = 14). Before and after an in-season phase (24 days), exercise HR (HRex) and HR recovery (HRR) expressed either as the number of beats recovered (HRR60s) or as the mean HR (HRpost1) during 1 minute of recovery were analyzed. Heart rate measures were expressed as the % of maximal HR. Session rating of perceived exertion (sRPE) was computed for all training/match sessions. Group and individual HR changes were analyzed using magnitude-based inferences. Pearson correlation coefficients were also used to examine the relationships. Group analyses of HR changes revealed there were possibly to likely trivial changes in all HR measures. When analyzing individual data, no substantial change was observed for HRR60s%. However, substantial changes in HRex% and HRpost1% were observed for 4/14 and 5/14 players, respectively. The relationships between HRex% and HRpost1% were nearly perfect (r = 0.90, confidence limits [0.82-0.95]). The associations between changes in HRex% and HRpost1% were also nearly perfect (r = 0.92, 0.80-0.97). A very large inverse correlation was observed between HRex% and accumulated sRPE (r = -0.75, -0.44 to -0.90). This study highlights the value of conducting individual vs. group aerobic fitness monitoring. This study also showed the importance of how HRR is reported when aerobic fitness monitoring of elite soccer players.
    • 'Friends as enemies': A sociological analysis of the relationship among touring professional golfers

      Fry, John; Bloyce, Daniel; University of Chester (SAGE, 2015-08-06)
      This paper examines the relationship among male touring professional golfers from a figurational sociological standpoint. The paper is based on 20 interviews from players with experience playing at various levels on the EPGA professional tours and a level ‘above’ that. The results indicate a workplace culture where many begin to adopt the attitudes and behaviors that encourage the development of networks of temporary ‘we-group’ alliances. The ‘touring’ aspects of professional golf means many players strive to forge these alliances to help reduce feelings of loneliness, isolation, and homesickness while away for long periods of time. Such stresses are intensified given the globalization of sport generally and the associated increases in labor market migration that has become commonplace. The urge to develop friendship networks constrains players to behave in a manner expected of them rather than in a way that reflects their actual emotions, such as maintaining a positive attitude during difficult times like spells of poor performances and time away from their families. The relationships among players on tour is, however, non-permanent and/or partially changeable. Players are ‘friends’, characterized by togetherness and camaraderie, while, at the same, showing evidence of tensions and conflict as they are ultimately in direct competition with each other for a share of the overall prize money. Key words: professional golf, workplace relations, sport labor migration, figurational sociology, friendship networks
    • From public issues to personal troubles: individualising social inequalities in health within local public health partnerships

      Mead, Rebecca; Thurston, Miranda; Bloyce, Daniel; University of Lancaster; Inland Norway University of Applied Sciences; University of Chester (Taylor and Francis, 2020-05-20)
      This paper explores public health policy implementation through partnership working at the local level by examining how local actors from public health and the wider workforce, make sense of and work on social inequalities in health. An ethnographic case study was used to examine policy implementation in one local strategic partnership in north-west England during a period of significant resource constraint. Semi-structured interviews were the primary method of data generation. Sensitising concepts from figurational sociology were used to develop a theoretical account of how local policy implementation directed at narrowing social inequalities in health tended to give rise to relatively fragmented and short-term services, projects and practices, which focused on lifestyle factors and behaviour change. Theorising partnership work as figurations goes some way to explaining the apparent paradox among participants who expressed a relatively detached appreciation of wider social influences, alongside emotional involvement in their work. This process of individualisation explains how local professionals tended to conceptualise health inequality and the social determinants of health as personal troubles. Individualisation meant that the social reality of working in partnerships on difficult issues was simplified. Thus, any scope for working on the social determinants of health tended to be overlooked. The extent to which this was intentional or a matter of struggling to see opportunities, or a mixture of the two, was difficult to discern. Although the policy landscape has changed, the findings give some insight into understanding how local collaborative processes reproduce local public health work underpinned by lifestyle choices.
    • From Surveillance to Intervention: Overview and Baseline Findings for the Active City of Liverpool Active Schools and SportsLinx (A-CLASS) Project

      McWhannell, Nicola; Foweather, Lawrence; Graves, Lee; Henaghan, Jayne; Ridgers, Nicola D.; Stratton, Gareth; University of Chester; Liverpool John Moores University, Laude Lady Elizabeth Junior School, Deakin University, Swansea University (MDPI, 2018-03-23)
      This paper outlines the implementation of a programme of work that started with the development of a population-level children’s health, fitness and lifestyle study in 1996 (SportsLinx) leading to selected interventions one of which is described in detail: the Active City of Liverpool, Active Schools and SportsLinx (A-CLASS) Project. The A-CLASS Project aimed to quantify the effectiveness of structured and unstructured physical activity (PA) programmes on children’s PA, fitness, body composition, bone health, cardiac and vascular structures, fundamental movement skills, physical self-perception and self-esteem. The study was a four-arm parallel-group school-based cluster randomised controlled trial (clinical trials no. NCT02963805), and compared different exposure groups: a high intensity PA (HIPA) group, a fundamental movement skill (FMS) group, a PA signposting (PASS) group and a control group, in a two-schools-per-condition design. Baseline findings indicate that children’s fundamental movement skill competence levels are low-to-moderate, yet these skills are inversely associated with percentage body fat. Outcomes of this project will make an important contribution to the design and implementation of children’s PA promotion initiatives.
    • Girls, young women and sport in Norway: A case study of sporting convergence amid favourable socio-economic conditions

      Green, Ken; Thurston, Miranda; Vaage, Odd; Mordal-Moen, Kjersti; University of Chester; Hedmark University (Taylor & Francis, 2015-04-14)
      Based primarily on quantitative data from the Norwegian Statistisk Sentralbyrå (Statistics Norway) study of Mosjon, Friluftsliv og Kulturaktiviteter, this paper explores sports participation among females – and girls and young women, in particular – in Norway in the early years of the twenty-first century. In line with the observation that sport can be considered epiphenomenal, the paper argues that the comparatively high levels and marked increases in sports participation among young women are likely to have a great deal to do with their socio-economic status and, in particular, the diminishing gender gap over the past two decades. In short, the paper argues that trends in sports participation between 1997 and 2007 suggest that while young women in Norway may not be self-described feminists, they are heirs to the culture fostered by second-wave feminism: they have taken advantage of growing up in a country where standards of living are particularly high and at a time of greater equality between the sexes in order, among other things, to exploit the sporting opportunities increasingly available to them. In terms of the policy implications, the most salient lesson to be learned from the Norwegian situation – by countries keen to promote sports participation among girls and young women – is that instead of individually oriented approaches, sports policies need first and foremost to adopt society-level perspectives that address socio-economic gender disparities.
    • Glutamine supplementation reduces markers of intestinal permeability during running in the heat in a dose-dependent manner

      Pugh, Jamie; Sage, Stephen; Hutson, Mark; Doran, Dominic; Fleming, Simon; Highton, Jamie M.; Morton, James; Close, Graeme (Springer, 2017-10-20)
      Purpose To examine the dose–response effects of acute glutamine supplementation on markers of gastrointestinal (GI) permeability, damage and, secondary, subjective symptoms of GI discomfort in response to running in the heat. Methods Ten recreationally active males completed a total of four exercise trials; a placebo trial and three glutamine trials at 0.25, 0.5 and 0.9 g kg−1 of fat-free mass (FFM) consumed 2 h before exercise. Each exercise trial consisted of a 60-min treadmill run at 70% of ̇VO2max in an environmental chamber set at 30 °C. GI permeability was measured using ratio of lactulose to rhamnose (L:R) in serum. Plasma glutamine and intestinal fatty acid binding protein (I-FABP) concentrations were determined pre and post exercise. Subjective GI symptoms were assessed 45 min and 24 h post-exercise. Results Relative to placebo, L:R was likely lower following 0.25 g kg−1 (mean difference: − 0.023; ± 0.021) and 0.5 g kg−1 (− 0.019; ± 0.019) and very likely following 0.9 g kg− 1 (− 0.034; ± 0.024). GI symptoms were typically low and there was no effect of supplementation. Discussion Acute oral glutamine consumption attenuates GI permeability relative to placebo even at lower doses of 0.25 g kg−1, although larger doses may be more effective. It remains unclear if this will lead to reductions in GI symptoms. Athletes competing in the heat may, therefore, benefit from acute glutamine supplementation prior to exercise in order to maintain gastrointestinal integrity.
    • “The helping, the fixtures, the kits, the gear, the gum shields, the food, the snacks, the waiting, the rain, the car rides…”: Social Class, Parenting and Children’s Organised Leisure

      Wheeler, Sharon; Green, Ken; Edge Hill University; University of Chester (Taylor & Francis, 2018-05-11)
      Class-related parenting cultures and ideologies have been of considerable interest to academics over the last two decades. Much of the research thus far has focused on exploring Annette Lareau’s conceptualisations of ‘natural growth’ and ‘concerted cultivation’ and the implications for outcomes in relation to education. The focus of the present article is organised activities, which are a central but as yet relatively under-researched feature of middle-class parenting. The findings are based upon 73 semi-structured interviews with parents and children from 48 middle-class families living in and around a small city in northern England. The article reveals that initiating and facilitating children’s organised activities is considered a central aspect of ‘good’ parenting in middle-class social networks. It is shown how this is a consequence of several developments within society over the past three decades or so, including the rising levels of maternal employment, the growing competitiveness of the labour market and the increasing concerns related to children’s health and safety. It is argued that these developments have heightened middle-class parents’ predisposition to not only be involved with and invest in their children’s leisure biographies, but to do so in a more deliberate, rigorous and rational manner.
    • Including pupils with special educational needs in secondary school physical education: A sociological analysis of teachers' views

      Smith, Andy; Green, Ken; University College Chester (Taylor & Francis, 2004-11)
      This paper explores physical education (PE) teachers' views of the inclusion of pupils with special educational needs (SEN) in PE from a figurational sociological perspective. Starting from the premise that teachers' views cannot be adequately explained by studying the concept of inclusion or the teacher in isolation, it is argued that we can only begin to make sense of such views by locating teachers within the figurations of which they are a part and by exploring two particularly salient features of those figurations: namely, teachers' habituses and contexts. In doing so, the paper focuses upon the training teachers receive, the constraints imposed upon them by their colleagues and pupils, and, most importantly, the suitability of the National Curriculum for meeting the needs of pupils with SEN. The paper concludes by highlighting some of the unintended consequences of the inclusion of pupils with SEN in PE.
    • Inclusion, special educational needs, disability and physical education

      Smith, Andy; Thomas, Nigel; University College Chester ; Staffordshire University (SAGE, 2004-10-05)
      This book chapter explores some of the aspects of the complex inter-relationships and issues surrounding the inclusion of pupils with special educational needs (SEN)and disabilities in physical education. It focuses on the revised National Curriculum for Physical Education (2000) and dicusses sports suitable for pupils with SEN, the role of staff, assessing pupils with SEN and disabilities, and the experiences of pupils with SEN and disabilities in physical education.
    • Individual differences and risk taking in rock climbing

      Llewellyn, David J.; Sanchez, Xavier; University of Cambridge : University of Chester (Elsevier, 2008-07)
      This article discusses the notion that risk taking populations are homogenous, and that risk taking in sport necessarily reflects the expression of trait sensation seeking. 116 active rock climbers took part in a quantitative cross-sectional study.
    • Influence of contextual factors, technical performance and movement demands on the subjective task load associated with professional rugby league match-play

      Mullen, Thomas; Twist, Craig; Daniels, Matthew; Dobbin, Nick; Highton, Jamie; University of Chester
      Purpose: The aim of the study was to identify the association between several contextual match factors, technical performance and external movement demands on the subjective task load of elite rugby league players. Methods: Individual subjective task load, quantified using the National Aeronautics and Space Administration Task Load Index (NASA-TLX), was collected from 29 professional rugby league players from one club competing in the European Super League throughout the 2017 season. The sample consisted of 26 matches, culminating in 441 individual data points. Linear mixed-modelling was adopted to analyze the data for relationships and revealed that various combinations of contextual factors, technical performance and movement demands were associated with subjective task load. Results: Greater number of tackles (effect size correlation ± 90% CI; η2= 0.18 ±0.11), errors (η2= 0.15 ±0.08) decelerations (η2= 0.12 ±0.08), increased sprint distance (η2= 0.13 ±0.08), losing matches (η2= 0.36 ±0.08) and increased perception of effort (η2= 0.27 ±0.08) led to most likely – very likely increases in subjective total task load. The independent variables included in the final model for subjective mental demand (match outcome, time played and number of accelerations) were unclear, excluding a likely small correlation with the number of technical errors (η2= 0.10 ±0.08). Conclusions: These data provide a greater understanding of the subjective task load and their association with several contextual factors, technical performance and external movement demands during rugby league competition. Practitioners could use this detailed quantification of internal loads to inform the prescription of recovery sessions and current training practices.
    • The influence of different work and rest distributions on performance and fatigue during simulated team handball match play

      Moss, Samantha L.; Twist, Craig; University of Chester (Lippincott, Williams & Wilkins, 2015-05-05)
      This study investigated the effect of different interchange strategies on performance and pacing strategy during a simulated team-sports protocol. Eight youth male team handball players completed two conditions (LONG; work: 3 x 13:00 min, rest: 8:00 min, SHORT; work: 5 x 7:48 min, rest: 3:45 min). Participants were tested for 20 m sprint, counter-movement jump, throwing performance and heart rate during conditions. Postcondition measures included repeated shuttle-sprint and jump ability, session rating of perceived exertion, blood lactate and glucose. Faster sprint (3.87 ± 0.27 s cf. 3.97 ± 0.24 s, ES = 0.39, P= 0.03) and throwing performance (70.02 ± 7.40 km*h-1 cf. 69.04 ± 5.57 km*h-1, P> 0.05, ES = -0.15) occurred in SHORT compared to LONG by a 'likely small' difference. Higher summated heart rate (157 ± 21 cf. 150 ± 15 AU) occurred in SHORT compared to LONG by a 'likely small' difference (ES = 0.37, P> 0.05). SHORT resulted in lower session rating of perceived exertion (224 ± 45 AU cf. 282 ± 35 AU, ES = 1.45, P= 0.001) and higher blood glucose (6.06 ± 0.69 mmol*l-1 cf. 4.98 ± 1.10 mmol*l-1, ES = -1.17, P= 0.03) by a 'most likely moderate' difference compared to LONG. Repeated shuttle-sprint was better preserved after SHORT, with 'moderately lower' 10 m and 25 m times (P< 0.05). Interchange strategies using SHORT rather than LONG work and rest periods result in lower physiological load, leading to improved fatigue resistance and better preservation of high-intensity movements during matches.
    • The influence of music genre on explosive power, repetitions to failure and mood responses during resistance exercise

      Moss, Samantha L.; Enright, Kevin; Cushman, Simon; University of Chester; Liverpool John Moores University (Elsevier, 2018-05-04)
      Objectives: To investigate the influence of different music genres on the psychological, psychophysical and psychophysiological responses during power-based and strength-based resistance exercises. Design: Repeated-measures counterbalanced design. Method: Sixteen resistance-trained participants completed an explosive power test in the squat and bench exercises at 30% 1RM across no music, electronic dance music, metal and self-selected conditions. Peak and mean values were recorded for power and velocity. A progressive loading protocol assessed the impact of condition on repetitions to failure at 60, 70 and 80% 1RM in the squat and bench exercises. For all tests, recording of heart rate and rating of perceived exertion were completed after every set, blood lactate after protocol completion, and mood states before and after. Results: Using magnitude-based inferences, music either had no effect or a small detrimental effect on power and velocity, depending on the exercise. Repetitions to failure increased by a small to moderate amount for all music conditions compared to no music at low but not high intensities. Self-selected music provided additional small benefits in repetitions than other music conditions. Rating of perceived exertion was similar between self-selected, metal and no music conditions, whereas electronic dance music revealed higher responses. Vigour increased after all music conditions but remained unchanged in no music. Conclusions: Explosive power exercises either remain unchanged or are disadvantaged when completed to music. Various music genres could improve repetition to failure training at low to moderate intensities, although individuals might expect greatest improvements using self-selected music, without concomitant increases in perceived effort.
    • Influence of Playing Standard on Upper- and Lower-Body Strength, Power, and Velocity Characteristics of Elite Rugby League Players

      Fernandes, John; Daniels, Matthew; Myler, Liam; Twist, Craig (MDPI, 2019-04-17)
      Background: To compare load–velocity and load–power relationships among first grade (n = 26, age 22.9 ± 4.3 years), academy (n = 23, age 17.1 ± 1.0 years), and scholarship (n = 16, age 15.4 ± 0.5 years) Super League rugby league players. Methods: Participants completed assessments of maximal upper- and lower-body strength (1RM) and peak velocity and power at 20, 40, 60, and 80 kg during bench press and squat exercises, in a randomised order. Results: Bench press and squat 1RM were highest for first grade players compared with other standards (effect size (ES) = −0.43 to −3.18). Peak velocities during bench and squat were greater in the higher playing standards (ES = −0.39 to −3.72 range), except for the squat at 20 and 40 kg. Peak power was higher in the better playing standards for all loads and exercises. For all three groups, velocity was correlated to optimal bench press power (r = 0.514 to 0.766), but only 1RM was related to optimal power (r = 0.635) in the scholarship players. Only squat 1RM in the academy was related to optimal squat power (r = 0.505). Conclusions: Peak velocity and power are key physical qualities to be developed that enable progression from junior elite rugby league to first grade level. Resistance training should emphasise both maximal strength and velocity components, in order to optimise upper- and lower-body power in professional rugby league players.
    • The influence of preseason training phase and training load on body composition and its relationship with physical qualities in professional junior rugby league players

      Dobbin, Nick; Gardner, Adrian; Daniels, Matthew; Twist, Craig; University of Chester (Taylor & Francis, 2018-05-08)
      This study investigated changes in body composition in relation to training load determined using RPE and duration (sRPE), and its relationship with physical qualities over a preseason period. Sixteen professional academy players (age = 17.2 ± 0.7 years; stature = 179.9 ± 4.9 cm; body mass = 88.5 ± 10.1 kg) participated in the study. Body composition was assessed before and after each training phase and physical qualities assessed at the start and end of preseason. Across the whole preseason period, skinfold thickness, body fat percentage and fat mass were most likely lower (ES = -0.73 to -1.00), and fat free mass and lean mass were likely to most likely higher (ES = 0.31 to 0.40). Results indicated that the magnitude of change appeared phase-dependent (ES = -0.05 to -0.85) and demonstrated large individual variability. Changes in physical qualities ranged from unclear to most likely (ES = -0.50 to 0.64). Small to moderate correlations were observed between changes in body composition, and TL with changes in physical qualities. This study suggests training phase and TL can influence a player’s body composition; that large inter-participant variability exists; and that body composition and TL are related to the change in physical qualities.
    • The influence of sprint spike bending stiffness on sprinting performance and metatarsophalangeal joint function

      Smith, Grace; Lake, Mark; Sterzing, Thorsten; Milani, Thomas; University of Chester; Liverpool John Moores University; Chemnitz University of Technology. (Taylor and Francis, 2016-06-07)
      There is evidence that increasing the longitudinal bending stiffness of sprinting footwear can lead to improved sprinting performance although this has not yet been established. This study examined the effect of four known shoe stiffness conditions on both sprinting performance and metatarsophalangeal joint (MTPJ) motion. Twelve trained sprinters performed 40 m maximal sprints along an indoor running track, two sprints in each stiffness condition, and high speed video (600 Hz) recorded two dimensional MTPJ motion during ground contact. To explore individual responses to the footwear manipulations, three dimensional (1000 Hz) kinematic and kinetic data was collected during maximal sprinting for two sprinters. At the group-level, increasing shoe bending stiffness elicited no significant differences in sprinting performance or MTPJ motion, with any changes between conditions being subject-specific. In-depth individual analyses revealed that increased shoe stiffness could restrict motion about the MTPJ and there appeared to be a preferred stiffness for best performance. This notion of individual optimal sprint shoe stiffness and what factors might contribute to the optimum requires further investigation.
    • The influence of warm-up duration on simulated rugby league interchange match performance

      Williams, Robert; Gillham, Scott; Highton, Jamie; Twist, Craig; University of Chester
      Objective: The study was conducted to understand the effects of a short (10-minute) and a long (30-minute) duration warm-up on subsequent readiness to exercise and movement during simulated rugby league match play. Methods: Using a randomised cross-over design, 13 male rugby players (age: 23.6 ± 4.1 y) completed a 10- or 30-minute warm-up immediately before 2 x 23 min rugby league movement simulation protocol. Comparisons of the responses to the warm-up and during the simulation were made between each trial. Results: Total distance, high- and low speed running and tympanic temperature (ES = 0.56 to 20.8) were all higher in the 30 min warm-up, with differences in relative distance and heart rate unclear (ES = -0.36 to 0.06). Differences in participants’ readiness to exercise after the warm-ups were unclear (ES = 0.25). Differences between trials for movement characteristics (ES = -0.13 to -0.32), RPE (ES = -0.13 to 0.04) and B[La] after the simulation were mostly unclear, with only trivial changes in high-speed running (ES = 0.08) and a lower heart rate (ES = -0.26) between the two playing bouts after the 30 min warm-up trial. Conclusion: Practitioners can use warm-ups between 10 or 30 minutes for rugby league interchange players without any implications for subsequent match running performance.
    • 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.
    • The interaction between the physical and mental loads associated with actual and simulated rugby league performance

      Highton, Jamie; Twist, Craig; Mullen, Thomas (University of Chester, 2019-09)
      The aim of the current thesis was to develop knowledge of the ‘loads’ associated with rugby league match-play, with a particular focus on the effects of altered mental loads before and during exercise indicative of a rugby league match. Chapter 3 examined the test-retest reliability of movement, physiological and perceptual measures during and after a novel rugby match simulation, where movement commands were more random than those typical of match simulations. The most reliable measure of external load during bouts of the simulation was relative distance (typical error [TE] and coefficient of variation [CV%] = 1.5-1.6 m.min-1 and 1.4-1.5%, respectively), with all other movement characteristics possessing a CV% <5%. The most reliable measure of internal load, neuromuscular function and perceptual measures were for %HRmax during bout 1 (TE and CV% = 1.4-1.7% and 1-4-2.1%, respectively), MVC before (TE and CV% = 10.8-14.8 N·m and 3.8-4.6%, respectively), and average RPE (TE and CV% = 0.5-0.8 AU and 3.6-5.5%, respectively). The conclusion of this chapter was that randomisation of the movements during simulated activity to better reflect intermittent team sports has no detrimental effect on its reliability. Studies can therefore confidently examine alterations in several perceptual, neuromuscular, physiological and movement load measures related to rugby activity using stochastic movements. Chapter 4 examined the responses to a simulated rugby league protocol that was designed to include more random commands, and therefore require greater vigilance, than traditional team sport simulation protocols. The randomised simulation (RDM) was matched for the number and types of activity performed every 5.45 min in a control trial (CON), but included no repeated cycles of activity. The RDM trial was more mentally demanding than CON (Effect size (ES) = 0.56; ±0.57). Self-paced mean sprint performance increased in RDM (22.5 ± 1.4 vs. 21.6 ± 1.6 km∙h-1; ES = 0.50; ±0.45), which was accompanied by a higher RPE (14.3 ± 1.0 vs. 13.0 ± 1.4; ES = 0.87; ±0.54) and a greater number of errors in the Stroop Test (10.3 ± 2.5 vs. 9.3 ± 1.4 errors; ES = 0.65; ±0.67). MVC peak torque (CON = -48.4 ± 31.6 N.m, RDM = -39.6 ± 36.6 N.m) and voluntary activation (CON = -8.3 ± 4.8%, RDM = -6.0 ± 4.1%) was similarly reduced in both trials. Providing more random commands, requiring greater vigilance, can therefore alter performance and associated physiological, perceptual and cognitive responses to team sport simulations. Chapter 5 describes the subjective task load of elite rugby league match play using the NASA-TLX and examines their association with several contextual match factors, technical ii performance and external movement demands. Linear mixed modelling revealed that various combinations of contextual factors, technical performance and movement demands were associated with subjective task load (NASA-TLX). Greater number of tackles (η2 = 0.18), errors (η2 = 0.15) decelerations (η2 = 0.12), increased sprint distance (η2 = 0.13), losing matches (η2 = 0.36) and increased perception of effort (η2 = 0.27) lead to most likely – very likely increases in subjective total workload. These data provide a greater understanding of the internal load and their association with several contextual factors, technical performance and external movement demands during rugby league competition. The purpose of the final empirical chapter (Chapter 6) was to describe the effects of mental fatigue on simulated rugby league performance and to determine the effects of caffeine supplementation on simulated rugby league performance in the presence of mental fatigue. Completing a mentally demanding task increases participants’ subjective rating of mental fatigue (pre = 29 ± 25 AU; post = 55 ± 20 AU) immediately before completing a simulation protocol. Impairments in sprint speed (ES = -0.18; ±0.19), sprint to contact speed (ES = -0.20; ±0.27), high-intensity running (ES = -0.30; ±0.24), high metabolic power > 20 W·kg-1 (ES =-0.50; ±0.51) and time to complete a passing accuracy task (ES = 0.54; ±0.63) were observed after mental fatigue. Caffeine supplementation (5 mg.kg-1) attenuated several adverse effects of mental fatigue before exercise replicating the demands of rugby league match play, with increased sprint speed (ES = 0.40; ±0.18), high-intensity running (ES = 0.50; ±0.53), high metabolic power > 20 W·kg-1 (ES = 0.33; ±0.38) and decreased time to complete a passing accuracy test (ES =-0.70; ±0.45). Mental fatigue affected internal loads, external loads and skill performance during simulated rugby league match play that appear to be centrally regulated by a decreased motivation and increased perception of effort. However, a single dose of caffeine taken 60 min before performance can attenuate several of these negative effects. In summary, the current thesis highlights several interactions between the physical and mental loads associated with actual and simulated rugby league performance.