• 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.
    • The effects of in-season, low-volume sprint interval training with and without sport-specific actions on the physical characteristics of elite academy rugby league players

      Dobbin, Nick; Highton, Jamie M.; Moss, Samantha; Twist, Craig (Human Kinetics, 2020-05-01)
      Purpose: To determine the utility of a running and rugby-specific, in-season sprint interval interventions in professional rugby league players. Methods: Thirty-one professional academy rugby players were assigned to a rugby-specific (SITr/s, n = 16) or running (SITr, n = 15) sprint interval training group. Measures of speed, power, change of direction (CoD) ability, prone Yo-Yo IR1 performance and heart rate recovery (HRR) were taken before and after the 2-week intervention as were sub-maximal responses to the prone Yo-Yo IR1. Internal, external and perceptual responses were collected during SITr/s/SITr, with wellbeing and neuromuscular function assessed before each session. Results: Despite contrasting (possible to most likely) internal, external and perceptual responses to the SIT interventions, possible to most likely within-group improvements in physical characteristics, HRR and sub-maximal responses to the prone Yo-Yo IR1 were observed after both interventions. Between-group analysis favoured the SITr/s intervention (trivial to moderate) for changes in 10 m sprint time, CMJ, change of direction and medicine ball throw as well as sub-maximal (280-440 m) high metabolic power, PlayerLoad™ and acceleratory distance during the prone Yo-Yo IR1. Overall changes in wellbeing or neuromuscular function were unclear. Conclusion: Two-weeks of SITr/s and SITr was effective for improving physical characteristics, HRR and sub-maximal responses to the prone Yo-Yo IR1, with no clear change in wellbeing and neuromuscular function. Between-group analysis favoured the SITr/s group, suggesting that the inclusion of sport- specific actions should be considered for in-season conditioning of rugby league players.
    • Effects of a four-week touch rugby and self-paced interval running intervention on health markers in active young men.

      Dobbin, Nick; Bloyce, Daniel; Hughes, Stephen; Twist, Craig (Springer, 2020-03-29)
      Background: Modified team sport activity has been proposed as effective exercise modality for promoting markers of health that are comparable or greater than continuous forms of activity. However, research using modified team sports is currently limited to sedentary populations using 2-3 sessions across a minimum of 8 weeks. Aim: To investigate the effects of a four-week touch rugby and self-paced interval running intervention on a range of health markers in active men. Methods: Sixteen participants (age 26.4 ± 6.4 years) were matched for age, demographic and physical activity before completing a single touch rugby (n = 8) or running (n = 8) session per week for four weeks. Measures of systolic and diastolic blood pressure, resting heart rate (RHR), body composition and biochemical status were recorded pre- and post-intervention. Results: ANCOVA analysis revealed between-group differences for impedance (P = 0.027), fat mass (P = 0.008), percentage body fat (P = 0.008) and fat free mass (P = 0.002), with greater changes after touch rugby. Systolic blood pressure decreased for both groups with greater reductions observed after touch rugby (P = 0.002). No between-group difference was observed for RHR, interleukin-6 or C-reactive protein (P > 0.05). Contrasting internal, external and perceptual loads were observed. Conclusion: The results of this study suggest that a single session of touch rugby over a 4-week period elicited greater improvements in body composition and SBP that self-paced running, with both equally beneficial for improving RHR, diastolic blood pressure and improved inflammatory status in active young men.
    • Delivering a sports participation legacy from the London 2012 Olympic and Paralympic Games: evidence from sport development workers in Birmingham and their experiences of a double-bind

      Lovett, Emily; Bloyce, Daniel; Smith, Andy; Edge Hill University; University of Chester (Taylor and Francis, 2020-03-11)
      Legacy promises from London 2012 meant that those working in sport in local, non-host areas in Britain were expected to facilitate more sporting opportunities for local citizens. Legacy preparations occurred in the context of many other constraints that stemmed from Government budget cuts and provision of leisure-time sport and other leisure activities. This paper presents new evidence on a significantly under-researched area of leisure studies, namely: the experiences of those delivering leisure-sport opportunities in a non-host city and how they responded to national legacy promises. Using Elias’s concept of the double-bind, we explain the ‘crisis situation’ in which some local sports workers were enmeshed and how their acceptance of ‘fantasy-laden beliefs’ of expected demonstration effects from mega-events exacerbated their ‘crisis’ (Elias, 2007). We also draw upon participants’ post-Games reflections to consider how future host nations may wish to leverage greater leisure-sporting legacies from a mega-event.
    • Analysis of physical demands during youth soccer match-play: Considerations of sampling method and epoch length

      Doncaster, Greg; Page, Richard; White, Paul; Svenson, Robert; Twist, Craig; Edge HIll University; Stoke City FC; University of Chester (Taylor and Francis, 2019-11-27)
      The purpose of this study was to examine the physical match profiles of professional soccer players using 3 and 5 min fixed and rolling averages as well as fixed 1 min averages, with considerations to training prescription. Twenty-nine, professional U23 soccer outfield players competed across 17 competitive matches during the 2017/18 season, equating to a total of 130 separate physical match profiles. Match activities were recorded using global positioning system (GPS) devices with integrated micro-electrical mechanical systems (MEMS), recording total distance (TD), high-speed running (HSR) and metabolic power (MP). For each individual match profile and variable, 1, 3 and 5 min peak, post-peak, and average values were calculated using fixed-time epochs (FIXED) and rolling averages (ROLL). Linear mixed models were employed to examine the differences in the dependent variables as a function of the method of measurement. Results revealed significantly higher peak values, for relative TD, relative HSR and relative MP when employing the ROLL sampling method, in comparison to the FIXED method, for both 3 min and 5 min epoch lengths. Analysis of epoch length revealed significantly higher peak values, across all positions, for relative TD, relative HSR and MP for 1 min epochs, in comparison to 3 min and 5 min epochs. The data offers a novel insight into the appropriate identification of physical demands during youth soccer match-play. Researchers and practitioners should consider the sampling method and epoch length when assessing the physical demands of competitive match-play, as well as when designing and prescribing sport-specific conditioning drills.
    • To Infinity and Beyond: The Use of GPS Devices within the Football Codes

      Malone, James; Barrett, Stephen; Barnes, Chris; Twist, Craig; Drust, Barry; Liverpool Hope University; Hull City FC; CB Sports Performance; University of Chester; Liverpool John Moores University (Taylor and Francis, 2019-10-17)
      The quantification of external load through global positioning systems (GPS) is now commonplace across the different football codes. Despite this acceptance amongst sports science practitioners, confusion still remains around which are the most appropriate metrics to use when monitoring their athletes. In addition, the translation of the message between the data gathered and the athletes and coaches can often be lost. The aim of this commentary is to provide discussion and recommendations when using GPS for athlete monitoring.
    • Stochastic ordering of simulated rugby match activity produces reliable movements and associated measures of subjective task load, cognitive and neuromuscular function

      Mullen, Thomas; Twist, Craig; Highton, Jamie; University of Chester (Taylor and Francis, 2019-07-31)
      The study assesses the test–retest reliability of movement and physiological measures during a simulated rugby match that employed activities performed in a stochastic order. Twenty male rugby players (21.4 ± 2.1 y) completed two trials of a 2 × 23 min rugby movement simulation protocol during which the order of events was performed in a stochastic order, with 7–10 days between trials. Movement characteristics, heart rate (HR), RPE, maximum voluntary contraction (MVC), voluntary activation (VA%) of the quadriceps, Stroop test and subjective task load rating (NASA-TLX) were measured. The most reliable measures of external load was relative distance (typical error [TE] and 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 (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 Stroop test, NASA-TLX and blood lactate produced the least reliable measures (CV% >5%). Future studies can confidently examine changes in several perceptual, neuromuscular, physiological and movement measures related to rugby activity using stochastic movements.
    • Norwegian youngsters’ perceptions of physical education: Exploring the implications for mental health

      Røset, Linda; Green, Ken; Thurston, Miranda; University of Chester (Taylor & Francis, 2019-06-24)
      Improving young people’s mental health has become a priority for policy-makers in Norway as elsewhere. Although the evidence is limited, physical activity has been identified as having a role in mental health promotion with school physical education (PE) typically being presented as a suitable setting. Few studies, however, have explored young people’s perceptions and experiences of PE and the possible consequences for their mental health – the departure point for this paper. We approach this issue sociologically by focusing on the processes through which PE is enacted. Qualitative data were generated by 31 focus groups involving 148 youngsters from the 10th grade (15–16-year-olds) in eight secondary schools in Norway. The overarching theme to emerge was that PE was valued by the students for what it was not as much as what it was. The appeal of PE often lay in being different and a break from ‘normal’ school lessons and, at the same time, an opportunity for informal social interaction and strengthening social bonds. Enjoyment of PE – even among those with limited sporting competence – was understood as giving rise to cathartic benefits and an antidote to their increasingly academic, routinized and performance-oriented school lives. However, processes relating to the organization, delivery and assessment of lessons meant that these benefits were sometimes compromised for some young people. We conclude that as far as the mental health of young people is concerned, the best justificatory defence for PE becomes physical recreation as a solution to (academic) schooling rather than PE as education.
    • A Narrative Review on Female Physique Athletes: The Physiological and Psychological Implications of Weight Management Practices

      Alwan, Nura; Moss, Samantha L.; Elliott-Sale, Kisrty; Davies, Ian; Kevin, Enright; Liverpool John Moores University; University of Chester; Nottingham Trent University (Human Kinetics, 2019-06-13)
      Physique competitions are events in which aesthetic appearance and posing ability are valued above physical performance. Female physique athletes are required to possess high lean body mass and extremely low fat mass in competition. As such, extended periods of reduced energy intake and intensive training regimens are utilised with acute weight loss practices at the end of the pre-competition phase. This represents an increased risk for chronic low energy availability and associated symptoms of Relative Energy Deficiency in Sport, compromising both psychological and physiological health. Available literature suggests that a large proportion of female physique athletes report menstrual irregularities (e.g., amenorrhea and oligomenorrhea), which are unlikely to normalise immediately post-competition. Furthermore, the tendency to reduce intakes of numerous essential micronutrients is prominent among those using restrictive eating patterns. Following competition reduced resting metabolic rate, and hyperphagia, are also a concern for these female athletes, which can result in frequent weight cycling, distorted body image and disordered eating/eating disorders. Overall, female physique athletes are an understudied population and the need for more robust studies to detect low energy availability and associated health effects is warranted. This narrative review aims to define the natural female physique athlete, explore some of the physiological and psychological implications of weight management practices experienced by female physique athletes and propose future research directions.
    • The World Anti-Doping Agency at 20: progress and challenges

      Houlihan, Barrie; Vidar Hanstad, Dag; Loland, Sigmund; Waddington, Ivan (Informa UK Limited, 2019-06-06)
    • Exercise-induced muscle damage and recovery in young and middle-aged males with different resistance training experience

      Fernandes, John; Lamb, Kevin L.; Twist, Craig (MDPI, 2019-05-29)
      This study compared the time course of recovery after a squatting exercise in trained young (YG; n = 9; age 22.3 ± 1.7 years) and trained (MT; n = 9; 39.9 ± 6.2 years) and untrained (MU; n = 9; age 44.4 ± 6.3 years) middle-aged males. Before and at 24 and 72 h after 10 × 10 squats at 60% one-repetition maximum (1RM), participants provided measurements of perceived muscle soreness (VAS), creatine kinase (CK), maximal voluntary contraction (MVC), voluntary activation (VA), and resting doublet force of the knee extensors and squatting peak power at 20% and 80% 1RM. When compared to the YG males, the MT experienced likely and very likely moderate decrements in MVC, resting doublet force, and peak power at 20% and 80% 1RM accompanied by unclear differences in VAS, CK, and VA after the squatting exercise. MU males, compared to MT, experienced greater alterations in peak power at 20% and 80% 1RM and VAS. Alterations in CK, MVC, VA, and resting doublet force were unclear at all time-points between the middle-aged groups. Middle-aged males experienced greater symptoms of muscle damage and an impaired recovery profile than young resistance trained males. Moreover, regardless of resistance training experience, middle-aged males are subject to similar symptoms after muscle-damaging lower-body exercise.
    • Pre-season training responses and their associations with training load in elite rugby league players

      Daniels, Matthew; Highton, Jamie M.; Twist, Craig; St Helens RFC; University of Chester (Taylor and Francis, 2019-05-07)
      Strength, power and endurance characteristics and their association with training load during a 7-week preseason training phase was assessed in elite rugby league players. Twenty-two players (age 23.3 ± 4.4 years) performed bench throw, one repetition maximum (1RM) bench press, squat jumps, three repetition maximum (3RM) squats, prone pull ups and prone Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1) before and after the 7-week preseason period. Training was classified into Gym, Field and Wrestle, with training load of each monitored using session rating of perceived exertion (sRPE) multiplied by training duration (sRPE-TL). There were most likely improvements in 3RM back squat, prone pull-ups and Yo-Yo IR1 and likely improvements in bench press, bench throw and squat jump after the 7-week training programme (ES = 0.3 to 1.2). Accumulated sRPE-TL for Gym, Field and Wrestle sessions was 9176 ± 1187, 10906 ± 2162, and 1072 ± 315 AU, respectively. Relationships between mean weekly sRPE-TL and changes in physical qualities was trivial to large (r = -0.67 to 0.34). This study suggests sRPE-TL is unsuitable to detect dose-response relationships between training load and the changes in physical qualities of elite rugby league players during the pre-season period.
    • 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 reproducibility and external validity of a modified rugby league movement simulation protocol for interchange players

      Norris, Jonathan; Highton, Jamie M.; Twist, Craig; University of Chester (2019-04-01)
      Purpose: The study assessed the reliability and external validity of a rugby league movement simulation protocol for interchange players that was adapted to include physical contact between participants Methods: Eighteen rugby players performed two trials of a modified rugby league movement simulation protocol for interchange players (RLMSP-i), seven days apart. The simulation was conduced outdoors on artificial turf with movement speeds controlled using an audio signal. Micro-technology was used to measure locomotive and accelerometer (i.e. PlayerLoadTM) metrics for both bouts (~23 min each) alongside heart rate and RPE. Results: Reported for each bout, total distance (102 ± 3 and 101 ± 3 m.min-1), low-speed distance (77 ± 3 and 79 ± 4 m.min-1), high-speed distance (25 ± 3 and 22 ± 4 m.min-1), PlayerLoadTM (10 ± 1 and 10 ± 1 AU.min-1), PlayerLoadTM slow (3.2 ± 0.6 and 3.2 ± 0.6 AU.min-1), PlayerLoadTM 2D (6.0 ± 0.9 and 5.7 ± 0.8 AU.min-1) and heart rate (86 ± 5 and 84 ± 6 %HR max) were similar to match play. The coefficient of variation (%CV) for locomotive metrics ranged from 1.3 to 14.4%, accelerometer CV% 4.4 to 10.0%, and internal load 4.8 to 13.7%. All variables presented a CV% less than the calculated moderate change during one or both bouts of the simulation except high-speed distance (m.min-1), %HRpeak and RPE (AU). Conclusion: The modified RLMSP-i offers a reliable simulation to investigate influences of training and nutrition interventions on the movement and collision activities of rugby league interchange players.
    • Exercise, or exercise and diet for the management of polycystic ovary syndrome: a systematic review and meta-analysis

      Kite, Chris; Lahart, Ian; Afzal, Islam; Broom, David; Randeva, Harpal; Kyrou, Ioannis; Brown, James (2019-02-12)
      Background: Typically, management of PCOS focuses on lifestyle changes (exercise and diet), aiming to alleviate symptoms, and lower the associated risk of type 2 diabetes and cardiovascular disease. Our objective was to analyse evidence on the effectiveness of exercise in the management of PCOS, when compared to (i) usual care, (ii) diet alone, and (iii) exercise combined with diet, and also exercise combined with diet, compared to (i) control or usual care and (ii) diet alone. Methods: Relevant databases were searched (June 2017) with no time limit for trial inclusion. Eligible trials employed a randomised or quasi-randomised design to measure the chronic effects of exercise, or exercise and diet in women with PCOS. Results: Searches returned 2390 articles; of those, 27 papers from 18 trials were included. Results are presented as mean difference (MD) and 95% confidence intervals (95% CI). Compared with control, exercise had a statistical effect on change from baseline fasting insulin (MD − 2.44 μIU/mL, 95% CIs − 4.24 to − 0.64; very low-quality evidence), HOMA-IR (− 0.57, − 0.99 to − 0.14; very low-quality evidence), total cholesterol (− 5.88 mg/dL, − 9.92 to − 1.83; low-quality evidence), LDL cholesterol (− 7.39 mg/dL, − 9.83 to − 4.95; low-quality evidence), and triglycerides (− 4.78 mg/dL, − 7.52 to − 2.05; low-quality evidence). Exercise also improved VO2 max (3.84 ml/kg/min, 2.87 to 4.81), waist circumference (− 2.62 cm, − 4.13 to − 1.11), and body fat percentage (− 1.39%, − 2.61 to − 0.18) when compared with usual care. No effect was found for change value systolic/ diastolic blood pressure, fasting glucose, HDL cholesterol (all low-quality evidence), or waist-to-hip ratio. Many favourable change score findings were supported by post-intervention value analyses: fasting insulin (− 2.11 μIU/mL, − 3.49 to − 0.73), total cholesterol (− 6.66 mg/dL, − 11.14 to − 2.17), LDL cholesterol (− 6.91 mg/dL, − 12.02 to − 1.80), and VO2 max (5.01 ml/kg/min, 3.48 to 6.54). Statistically lower BMI (− 1.02 kg/m2, − 1.81 to − 0.23) and resting heart rate (− 3.26 beats/min − 4.93 to − 1.59) were also revealed in post-intervention analysis. Subgroup analyses revealed the greatest improvements in overweight/obese participants, and more outcomes improved when interventions were supervised, aerobic in nature, or of a shorter duration. Based on limited data, we found no differences for any outcome between the effects of exercise and diet combined, and diet alone. It was not possible to compare exercise vs diet or exercise and diet combined vs diet. Conclusion: Statistically beneficial effects of exercise were found for a range of metabolic, anthropometric, and cardiorespiratory fitness-related outcomes. However, caution should be adopted when interpreting these findings since many outcomes present modest effects and wide CIs, and statistical effects in many analyses are sensitive to the addition/removal of individual trials. Future work should focus on rigorously designed, well-reported trials that make comparisons involving both exercise and diet. Systematic review registration: This systematic review was prospectively registered on the Prospero International Prospective Register of Systematic Reviews (CRD42017062576)
    • Slowing the Reconstitution of W′ in Recovery With Repeated Bouts of Maximal Exercise

      Chorley, Alan; Bott, Richard; Marwood, Simon; Lamb, Kevin L.; University of Chester; Liverpool Hope University (Human Kinetics, 2019-02-01)
      Purpose: This study examined the partial reconstitution of the work capacity above critical power (W′) following successive bouts of maximal exercise using a new repeated ramp test, against which the fit of an existing W′ balance (W'bal) prediction model was tested. Methods: Twenty active adults, consisting of trained cyclists (n = 9; age 43 [15] y, V˙ O2max 61.9 [8.5] mL·kg−1·min−1) and untrained cyclists (n = 11; age 36 [15] y, V˙ O2max 52.4 [5.8] mL·kg−1·min−1) performed 2 tests 2 to 4 d apart, consisting of 3 incremental ramps (20 W·min−1) to exhaustion interspersed with 2-min recoveries. Results: Intratrial differences between recoveries demonstrated significant reductions in the amount of W′ reconstituted for the group and both subsets (P < .05). The observed minimal detectable changes of 475 J (first recovery) and 368 J (second recovery) can be used to monitor changes in the rate of W′ reconstitution in individual trained cyclists. Intertrial relative reliability of W′ reconstitution was evaluated by intraclass correlation coefficients for the group (≥.859) and the trained (≥.940) and untrained (≥.768) subsets. Absolute reliability was evaluated with typical error (TE) and coefficient of variation (CV) for the group (TE ≤ 559 J, CV ≤ 9.2%), trained (TE ≤ 301 J, CV ≤ 4.7%), and untrained (TE ≤ 720 J, CV ≤ 12.4%). Conclusions: The reconstitution of W′ is subject to a fatiguing effect hitherto unaccounted for in W'bal prediction models. Furthermore, the W'bal model did not provide a good fit for the repeated ramp test, which itself proved to be a reliable test protocol.
    • The discriminant validity of standardised testing battery and its ability to differentiate anthropometric and physical characteristics between youth, academy and senior professional rugby league players

      Dobbin, Nicholas; Moss, Samantha L.; Highton, Jamie M.; Twist, Craig; University of Chester (Human Kinetics, 2019-01-31)
      Purpose: To assess a standardised testing battery’s ability to differentiate anthropometric and physical qualities between youth, academy and senior rugby league players, and determine the discriminant validity of the battery. Methods: A total of 729 rugby league players from multiple clubs within England categorised as youth (n = 235), academy (n = 362) and senior (n = 132) players completed a standardised testing battery that included the assessment of anthropometric and physical characteristics during preseason. Data was analysed using magnitude-based inferences and discriminant analysis. Results: Academy players were most likely taller and heavier than youth players (effect size (ES) = 0.64 to 1.21), with possibly to most likely superior CMJ, medicine ball throw and prone Yo-Yo IR1 performance (ES = 0.23 to 1.00). Senior players were likely to most likely taller and heavier (ES = 0.32 to 1.84), with possibly to most likely superior 10 and 20 m sprint times, CMJ, CoD, medicine ball throw and prone Yo-Yo IR1 compared to youth and academy (ES = -0.60 to 2.06). The magnitude of difference appeared to be influenced by playing position. For the most part, the battery possessed discriminant validity with an accuracy of 72.2%. Conclusion: The standardised testing battery differentiates anthropometric and physical qualities of youth, academy and senior players as a group and, in most instances, within positional groups. Furthermore, the battery is able to discriminate between playing standards with good accuracy and might be included in future assessments and rugby league talent identification.
    • Associations between selected training stress measures and fitness changes in male soccer players

      Rabbani, Alireza; Kargarfard, Mehdi; Castagna, Carlo; Clemente, Filipe M.; Twist, Craig; University of Chester (Human Kinetics, 2019-01-24)
      Purpose: The purpose of this study was to investigate the relationship of accumulated Global Positioning System (GPS)-accelerometer-based and heart rate (HR)-based training metrics to changes in high-intensity intermittent running capacity during an in-season phase in professional soccer players. Method: Eleven male professional players (mean ± SD, age: 27.2 ± 4.5 years) performed the 30-15 Intermittent Fitness Test (30-15IFT) before and after a five-week in-season training phase, and the final velocity (VIFT) was considered as players’ high-intensity intermittent running capacity. During all sessions, Edwards’ training impulse (Edwards’ TRIMP), Banister’s TRIMP, Z5 TRIMP, training duration, total distance covered, New Body Load (NBL), high-intensity running performance (distance covered above 14.4 km•h-1), and very high-intensity running performance (distance covered above 19.8 km•h-1) were recorded. Results: The players’ VIFT showed a most likely moderate improvement (+4.3%, 90% confidence limits [3.1; 5.5%], effect size ES, 0.70 [0.51; 0.89]). Accumulated NBL, Banister’s TRIMP and Edwards’ TRIMP showed large associations (r = 0.51 to 0.54) with changes in VIFT. Very large relationship was also observed between accumulated Z5 TRIMP (r= 0.72) with changes in VIFT. Large-to-nearly perfect within-individual relationships were observed between NBL and some of the other training metrics (i.e., Edwards’ TRIMP, Banister’s TRIMP, training duration, and total distance) in 10 out of 11 players. Conclusions: HR-based training metrics can be used to monitor high-intensity intermittent running capacity changes in professional soccer players. The dose-response relationship is also largely detected using accelerometer-based metrics (i.e., NBL) to track changes in high-intensity intermittent running capacity of professional soccer players.
    • 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.
    • Passive heat maintenance after an initial warm-up improves high intensity activity during an interchange rugby league match simulation protocol.

      Fairbank, Matthew; Highton, Jamie M.; Twist, Craig; University of Chester (Lippincott, Williams & Wilkins, 2019-01-01)
      This study examined using passive heat maintenance to maintain core temperature after a warm-up and its effect on first half running performance in rugby players. Thirteen male rugby players completed this randomized crossover study. Tympanic temperature was taken before a warm-up and then after a further 15 minutes passive recovery either with (PHM) or without (CON) a passive heat maintenance garment. Participants then completed 23 min of the rugby league match simulation protocol (RLMSP-i). Differences in tympanic temperature were unclear between CON and PHM before (35.7 ± 1.3 cf. 36.0 ± 1.1oC; ES = 0.20) and during exercise (34.5 ± 0.1 cf. 35.2 ± 0.1oC; ES = 0.26-0.35). High-intensity running (ES = 0.27) and peak sprint speed were higher (ES = 0.46-0.56) during the PHM compared to the CON trial. Time spent above 20 W.kg-1 also increased in the first quartile of PHM compared to CON trial (ES = 0.18). All other between trial comparisons of performance were unclear. HRmean (ES = 0.38) was higher in PHM compared to CON, while differences in RPEmean (ES = -0.19) were unclear. There are small to large increases in high intensity work performed during a playing bout when rugby players wear a PHM garment after a warm-up. Rugby players should consider PHM during extended periods of time between a warm-up and starting a match.