• Quantification of physical contact and its influence on simulated performance and recovery in rugby players.

      Twist, Craig; Norris, Jonathan (University of Chester, 2018-08-07)
      The aim of this thesis was to investigate the influence of physical collisions on internal (physiological and perceptual) and external (locomotive and accelerometer) load during simulated rugby league performance and fatigue responses in the days after. Chapter 4 examined the influence of physical contact type on internal and external load using a traditional soft tackle bag and custom-built tackle sled. Using a traditional tackle bag to simulate physical collisions resulted in likely faster sprint to contact speed (16.1 ± 1.5 c.f. 14.8 ± 1.1 km.h -1 ) but possibly lower overall high-speed running distance (27.7 ± 2.4 c.f. 28.4 ± 2.6 m.min-1 ). Also, the heavier tackle sled likely increased time at 91-100% HRpeak (12:58 ± 13:21 c.f. 6:44 ± 8:06 min:s) and resulted in greater lower limb fatigue reflected by the likely larger decrease in countermovement jump (CMJ) performance (5.9 ± 4.9 c.f. 2.6 ± 5.4%). Also of note was the variation in number of tackles detected using the automatic tackle detection feature compared to the actual number in the match simulation. During the Bag and Sled simulations ~53 and ~59 tackles were detected compared to 48 performed. The purpose of Chapter 5 was to investigate the influence of sprint to contact speed and contact type on automatic tackle detection using microtechnology. Repetitions were divided into three speed categories; walking, jogging and striding (1, 2.5 and 4 m.s -1 ) and four conditions: i) no contact standing upright (NCST), ii) no contact dropping to the ground in a prone position (NCGR), iii) contact with the tackle bag and remaining upright (CST), iv) contact with the tackle bag and going to ground (CGR). Similar tackle detection accuracy was observed between NCGR and CST conditions with one tackle observed in 41 and 43% of trials, respectively. While CGR resulted in the greatest frequency of correct tackle detection (62%), during 16% of trials two tackles were detected. During NCST, there were no tackles detected and 100% accuracy. The PlayerLoadTM results demonstrated that the metric can detect differences in movement speed, the inclusion of physical contact and changes in orientation during short periods of activity (8-10 s). In Chapter 6 the rugby league movement simulation protocol for interchange players (RLMSP-i) was modified to include a tackle shield collision to investigate the reliability of PlayerLoadTM metrics to quantify collision load. The coefficient of variation (%CV) for locomotive metrics ranged from 1.3 to 14.4%, with greatest variability observed for high-speed running distance (8.0 and 14.4% for Bouts 1 and 2, respectively). Accelerometer metrics CV% were 4.4 to 10.0%, while internal load markers were 4.8 to 13.7%. All variables presented a CV% less than the calculated moderate change during one or both bouts of the match simulation except from high-speed distance (m.min-1 ), %HRpeak and RPE (AU). The aim of Chapter 7 was to investigate the influence of contact type on external load metrics including PlayerLoadTM derivatives whilst controlling for total running distance. Participants were randomly assigned to one group to complete the match simulation with either a tackle shield (n = 10), tackle bag (n = 7) or no-contact (n = 10). Total PlayerLoadTM, PlayerLoadTM 2D (AU), PlayerLoadTM slow (AU) and PlayerLoadTM slow-ratio (%) were analysed from the accelerometer in addition to high- and low-speed running and sprint speed. Total PlayerLoadTM was likely lower for the Bag group compared to the Run group (498 c.f. 460 AU), with no clear differences between the other groups. 3 PlayerLoadTM slow for the Shield group (167 ± 26 AU) was very likely greater than both the Bag (133 ± 11 AU) and Run groups (128 ± 20 AU) but no clear difference was observed between the Bag and Run groups. No differences were observed in PlayerLoadTM 2D between any groups. High-speed running distance was likely lower in the Shield group (1056 ± 225 m) compared to the Bag group (1326 ± 245 m) and very likely lower compared to the Run group (1318 ± 175 m). Total PlayerLoadTM is not sensitive to contact type during simulated rugby league activity but does reflect greater high-speed running distance during a rugby league match simulation. However, PlayerLoadTM slow can detect the types of contact and might be preferred for quantifying match and training loads associated with physical contact. The purpose of the final empirical chapter (Chapter 8) was to determine the influence of contact type on in neuromuscular, perceptual and biochemical parameters associated with exercise-induced muscle damage. The participants were again assigned to one of three groups to complete the match simulation with a tackle shield (n = 6), tackle bag (n = 7) or no contact (n = 7). In addition to internal and external load measured during the match simulation, venous blood, muscle function and soreness measures were collected immediately (+0), +24 and +72 hours after the match simulation. Upper body neuromuscular performance and knee flexion torque likely decreased in the Shield group +0 and +72 hours after the simulation compared to the other groups while CMJ power likely decreased more in the Run group. All three groups demonstrated a very likely increase in IL-6 and IL-10 concentration immediately after the match simulation, but differences between the groups were unclear and values returned to baseline +24 hours after the simulation. In conclusion, current automatic tackle detection metric should be used with caution, particularly in training sessions where physical contact is replicated. Instead PlayerLoadTM and associated derivatives from the embedded accelerometer can provide a useful measure of contact-specific load during training and competitive matches. Physical contact type affected external load by modifying a participant’s running strategy during simulated match performance, thereby influencing site-specific fatigue during and after a simulated rugby league match. However, regardless of contact type, large increases in cytokine and leukocyte concentration are apparent with a return to basal values 24 hours after. Therefore it is not recommended to use such biomarkers in applied settings to quantify the magnitude of muscle damage specifically associated with physical contact.
    • Quantification of the physical and physiological load of a boxing-specific simulation protocol

      Thomson, Edward; Lamb, Kevin L.; University of Chester (Taylor & Francis, 2017-03-24)
      The aim of the study was to determine the physical and physiological responses to simulated amateur boxing of 3 × 3-min rounds. Using an externally valid technical and ambulatory demand, 28 amateur boxers (mean ± SD; age 22.4 ± 3.5 years, body mass 67.7 ± 10.1 kg, stature 171 ± 9 cm) completed the protocol following familiarisation. The physiological load was determined continuously via collection of mean (HRmean) and peak (HRpeak) heart rate, breath-by-breath oxygen uptake ( ̇V O2), aerobic energy expenditure (EEaer), excess carbon dioxide production (CO2excess), ratings of perceived exertion (RPE) and post-performance blood lactate. Physical performance was quantified as the acceleration delivered to the target by punches. HRmean and HRpeak were found to exceed 165 and 178 b min−1, absolute ̇V O2 > 124.6 ml kg−1, EEaer > 30.7 kcal min−1 and acceleration via 78 punches >2697 g during each round. Mean blood lactate (4.6 mmol l−1) and CO2excess (438.7 ml min−1) were higher than typical resting values reflecting a notable anaerobic contribution. RPEs reinforced the intensity of exercise was strenuous (>6–8). For all measures, there were typical increases (p < 0.05; moderate ES) across rounds. Accordingly, boxers might consider high-intensity (>90% ̇V O2max) interval training in anticipation such exercise yields improvements in aerobic conditioning. Moreover, the current simulation protocol – the boxing conditioning and fitness test – could be used as a form of training per se and as a means to monitor intervention-based changes in aspects of boxing-related physiology and performance. 1.
    • Randomisation 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 M.; University of Chester (Taylor and Francis, 2019)
      The study assesses the test-retest reliability of movement and physiological measures during a simulated rugby match that employed activities performed in a random order. Twenty male rugby players (21.4 ± 2.1 y) completed two trials of a 2 x 23 min rugby movement simulation protocol during which the order of events was randomised, 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.
    • A re-appraisal of the reliability of the 20 m multi-stage shuttle run test

      Lamb, Kevin L.; Rogers, Louise; University of Chester (Springer-Verlag, 2007-03-07)
    • "Read with caution": A reply to Pickett et al

      Smith, Dave; Wright, Caroline J.; Bruce-Low, Stewart; Hale, Bruce; University College Chester ; University College Chester ; University College Chester ; Penn State University (British Association of Sport and Medicine, 2005-10-21)
      This article critiques a study by Pickett Lewis & Cash titled "Men, muscles, and body image: comparisons of competitive bodybuilders, weigh trainers, and athletically active controls" published in the British Journal of Sports Medicine in 2005.
    • Reduction in high intensity activity during senior elite rugby league matches

      Sykes, Dave; Twist, Craig; Lamb, Kevin L.; Nicholas, Ceri; University of Chester (2009-06)
    • The Relationship Between Match-Play Characteristics of Elite Rugby League and Indirect Markers of Muscle Damage

      Oxendale, Chelsea; Twist, Craig; Daniels, Matthew; Highton, Jamie M.; University of Chester; St Helens Rugby League Club (Human Kinetics, 2016)
      Purpose: Whilst exercise-induced muscle damage (EIMD) after a rugby league match has been well documented, the specific match actions that contribute to EIMD are unclear. Accordingly, the purpose of this study was to examine the relationship between the physical demands of elite rugby league matches and subsequent EIMD. Methods: Twenty-eight performances were captured using 10 Hz global positioning systems. Upper and lower body neuromuscular fatigue, creatine kinase (CK) and perceived muscle soreness were assessed 24 h before and at 12, 36 and 60 h after a competitive match. Results: High-intensity running was moderately higher in backs (6.6 ± 2.6 m•min-1) compared to forwards (5.1 ± 1.6 m•min-1), whereas total collisions were moderately lower (31.1 ± 13.1 cf. 54.1 ± 37.0). Duration (r = 0.9, CI: 0.77 to 0.96), total distance covered (r = 0.86, CI: 0.7 to 0.95) and distance covered over 18 km•h-1 (r = 0.76, CI: 0.51 to 0.91) were associated with increased CK concentration post-match. Total collisions and repeated high-intensity efforts (RHIE) were associated with large decrements in upper body neuromuscular performance (r = -0.48, CI: -0.74 to 0.02 and r = -0.49, CI: -0.77 to 0.05, respectively), muscle soreness (r = -0.68, CI: -0.87 to -0.1 and r = -0.66, CI: -0.89 to 0.21, respectively), and CK concentration (r = 0.67, CI: 0.42 to 0.85 and r = 0.73, CI: 0.51 to 0.87, respectively). Conclusion: Match duration, high-intensity running and collisions were associated with variations in EIMD markers, suggesting recovery is dependent on individual match demands.
    • 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 and Validity of A Submaximal Warm-Up Test for Monitoring Training Status in Professional Soccer Players.

      Rabbani, Alireza; Kargarfard, Mehdi; Twist, Craig; University of Isfahan; University of Chester (Lippincott, Williams & Wilkins, 2017-11-27)
      Two studies were conducted to assess the reliability and validity of a submaximal warm-up test (SWT) in professional soccer players. For the reliability study, 12 male players performed SWT over three trials, with one week between trials. For the validity study, 14 players of the same team performed SWT and 30-15 Intermittent Fitness Test (30-15IFT) 7 days apart. Week-to-week reliability in selected heart rate (HR) responses [exercise HR (HRex), HR recovery (HRR) expressed as the number of beats recovered within 1 min (HRR60s) and expressed as the mean HR during 1 min (HRpost1)], were determined using intraclass correlation coefficient (ICC) and typical error of measurement expressed as coefficient of variation (CV). The relationships between HR measures derived from SWT and the maximal speed reached at the 30-15IFT (VIFT) were used to assess validity. The range for ICC and CV values were 0.83 to 0.95 and 1.4 to 7.0% in all HR measures, respectively, with the HRex as the most reliable HR measure of SWT. Inverse large (r = -0.50, 90% confidence limits, CL (-0.78; -0.06)) and very large (r = -0.76, CL, -0.90; -0.45) relationships were observed between HRex and HRpost1 with VIFT in relative (expressed as the % of maximal HR) measures, respectively. SWT is a reliable and valid submaximal test to monitor high-intensity intermittent running fitness in professional soccer players. In addition, the test’s short duration (5-min) and simplicity mean that it can be used regularly to assess training status in high-level soccer players.
    • The reliability and validity of short-distance sprint performance assessed on a nonmotorized treadmill

      Highton, Jamie M.; Lamb, Kevin L.; Twist, Craig; Nicholas, Ceri; University of Chester (National Strength and Conditioning Association, 2012-02)
      This study examined the interday and intraday reliabilities and validities of various sprint performance variables on a nonmotorized treadmill (NMT) over distances of 10, 20, and 30 metres.
    • 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.
    • Reliability of ratings of perceived exertion during progressive treadmill exercise.

      Lamb, Kevin L.; Eston, Roger; Corns, David; University College Chester (Elsevier, 1999-10)
      OBJECTIVE: To assess the test-retest reliability (repeatability) of Borg's 6-20 rating of perceived exertion (RPE) scale using a more appropriate statistical technique than has been employed in previous investigations. The RPE scale is used widely in exercise science and sports medicine to monitor and/or prescribe levels of exercise intensity. The "95% limits of agreement" technique has recently been advocated as a better means of assessing within-subject (trial to trial) agreement than traditional indicators such as Pearson and intraclass correlation coefficients. METHODS: Sixteen male athletes (mean (SD) age 23.6 (5.1) years) completed two identical multistage (incremental) treadmill running protocols over a period of two to five days. RPEs were requested and recorded during the final 15 seconds of each three minute stage. All subjects successfully completed at least four stages in each trial, allowing the reliability of RPE responses to be examined at each stage. RESULTS: The 95% limits of agreement (bias +/- 1.96 x SDdiff) were found to widen as exercise intensity increased: 0.88 (2.02) RPE units (stage 1), 0.25 (2.53) RPE units (stage 2), -0.13 (2.86) RPE units (stage 3), and -0.13 (2.94) RPE units (stage 4). Pearson correlations (0.81, 0.72, 0.65, and 0.60) and intraclass correlations (0.82, 0.80, 0.77, and 0.75) decreased as exercise intensity increased. CONCLUSIONS: These findings question the test-retest reliability of the RPE scale when used to monitor subjective estimates of exercise intensity in progressive (or graded) exercise tests.
    • 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.
    • A reliable testing battery for assessing physical qualities of elite academy rugby league players

      Dobbin, Nicholas; Hunwicks, Richard; Highton, Jamie M.; Twist, Craig (2017-11-14)
      This study assessed the inter-day reliability of a testing battery for the assessment of physical qualities of rugby league players. Fifty players (age 17.1 ± 1.1 years; stature 181.3 ± 6.3 cm; body mass 89.0 ± 11.6 kg) from three Super League academies participated in this study. Tests of countermovement jump performance, 10 and 20 m sprint performance, change of direction, medicine ball throw and a modified Yo-Yo Intermittent Recovery Test Level 1 (prone Yo-Yo IR1) were completed on three separate occasions. Between-day intraclass correlation coefficient, typical error (TE), coefficient of variation (CV) and the smallest worthwhile change (SWC) were calculated to determine the reliability and sensitivity of each measure. Individual tests (except medicine ball throw) were not systematically different between trials (P>0.05), with an inter-day variability that was <10%. In all instances, the TE was larger than the calculated SWC change although variability was less than that typically observed after a training intervention or specific training period (i.e. preseason). Using a magnitude-based inference approach, we present the required change for all performance tests to be 75% confident the change is beneficial. This simple and time efficient testing battery is sufficiently reliable to detect previously observed changes in a range of physical qualities of 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.
    • The reproducibility of perceptually regulated exercise responses during short-term cycle ergometry

      Hartshorn, James E. O.; Lamb, Kevin L.; University of Chester (Georg Thieme Verlag, 2004-05-18)
      The purpose of this study was to assess the reproducibility over four trials of perceptually regulated exercise intensity during short-term cycle ergometry. Recent research has suggested that an improvement in the reproducibility (better agreement) of the exercise output would be observed with a repeated practice of using regulatory tools such as Borg’s 6-20 rating of perceived exertion (RPE) scale. Eighteen healthy active volunteers (nine males mean age (± SD) 24.7 ± 3.4 yr, and nine females 27.6 ± 5.4 yr) completed four identical intermittent effort production trials on a cycle ergometer, over a period of two-three weeks, with all trials being between three and five days apart. After warm-up, the volunteers were asked to produce four x three-minute bouts of exercise at RPE levels: 13, 15, 9, and 17 (in this order). Power output (W), percentage maximum heart rate reserve (%MHRR), and oxygen consumption (VO2; ml•kg-1•min-1) were recorded in the final minute of each bout. Analysis revealed that the 95% limits of agreement (LoA) between repeated trials did not decrease for the objective markers of exercise intensity, remaining wide throughout. In the worst case comparisons the LoA represented changes (expressed as a proportion of the mean of two trials) of up to 58.3% in power output (T2 vs. T3 at RPE 9), 65.5% in %MHRR (T1 vs. T2 at RPE 13) and 36.5% in VO2 (T3 vs. T4 at RPE 17). These findings question the use of ratings of perceived exertion to regulate exercise effort. That the reproducibility of effort is also not seen to improve with practice raises doubts over the validity of using the RPE scale for providing training intensities for this type of exercise.
    • Reproducibility of the internal load and performance-based responses to simulated amateur boxing

      Thomson, Edward; Lamb, Kevin L.; University of Chester (Lippincott, Williams & Wilkins, 2017-12-01)
      The aim of this study was to examine the reproducibility of the internal load and performance-based responses to repeated bouts of a three-round amateur boxing simulation protocol (BOXFIT). Twenty-eight amateur boxers completed two familiarisation trials before performing two complete trials of the BOXFIT, separated by 4-7 days. To characterise the internal load, mean (HRmean) and peak (HRpeak) heart rate, breath-by-breath oxygen uptake (V ̇O2), aerobic energy expenditure (EEaer), excess carbon dioxide production (CO2excess) and ratings of perceived exertion (RPE) were recorded throughout each round and blood lactate determined post-BOXFIT. Additionally, an indication of the performance-based demands of the BOXFIT was provided by a measure of acceleration of the punches thrown in each round. Analysis revealed there were no significant differences (P > 0.05) between repeated trials in any round for all dependent measures. The typical error (coefficient variation %) for all but one marker of internal load (CO2excess) was 1.2 – 16.5% and reflected a consistency that was sufficient for the detection of moderate changes in variables owing to an intervention. The reproducibility of the punch accelerations was high (CV% range = 2.1 – 2.7%). In general, these findings suggest that the internal load and performance-based efforts recorded during the BOXFIT are reproducible and thereby offers practitioners a method by which meaningful changes impacting on performance could be identified.
    • Research is a messy process: A case study of a figurational sociology approach to conventional issues in social science research methods

      Bloyce, Daniel; University College Chester (2004)
      This article aims to provide an overview of a figurational approach to research methods by utilising a case study of specific research undertaken into the global diffusion of baseball. The article outlines the figurational approach to research in general; in other words, what 'doing' figurational research entails and provides outlines of how this approach necessarily impacts on one's research strategy, design and methods, respectively.
    • A retrospective analysis of talent selection and progression within England’s Rugby Football Union Elite Player Performance Pathway

      Worsfold, Paul R.; Green, Ken; Velentza, Elisavet (University of Chester, 2017-02)
      The England Rugby Football Union (RFU) Elite Player Performance Pathway (EPPP) is a player development system, structured into five playing squads (Under 18 [U18], Under 20 [U20], National academy [NA, age: 18-23 years], Saxons [Saxon, age: 18+ years] and Senior National Squad [SNS, age: 18+ years]), which attempts to develop players to play within the SNS. Despite its importance however, there is yet to be any scientific appraisal of its efficacy in successfully producing SNS players. Appraising the performances of 396 players enrolled on to the EPPP between 2008 and 2014, the purpose of this programme of research was therefore to investigate the nature of player transition and determine the key features associated with match performance between respective squads of the EPPP. To achieve this, the progression rates to subsequent squads, and the anthropometrical and position-specific technical performance data was quantified in conjunction with individual player progression within the EPPP system. Of the 396 players assessed within the thesis, 121 reached the SNS. Involvement in the EPPP was defined by high rates of de-selection during progression to subsequent squads and this was most apparent within the U18, U20 and NA squads. Analyses revealed the proportion of selected players for higher squads was 48.70%, 37%, 57.10% and 61% for U18-U20, U20-NA, NA-Saxon and Saxon-SNS squads, respectively. Within the SNS (n = 121), only 5.80% experienced a linear development (U18-U20-NA-Saxons-SNS) whereas all other players displayed variability with respect to squad pathway trajectories (NA-SNS 0.82%, Saxon-SNS: 50.4%, U20-Saxon-SNS 4.95%, NA-Saxon-SNS 12.39%, U18-U20-NA SNS:2.57%, U18-U20-Saxon-SNS 3.30%, U20-NA-Saxon-SNS 2.47%, side entries [selection from outside the EPPP system] 17.35%) within the EPPP. Thus, progression within the talent development (TDE) system was typified by variable patterns of sequential selection and de-selection processes throughout U18 to senior squads. The prerequisite level of technical performance indicators (TPI), related to generic and position-specific performance characteristics, and anthropometrical features (body mass and stature) specific to six predefined positional groups (front row [FR], second row [SR], Back row [BR], scrumhalf [SH], inside backs [IB], outside backs [OB]), were examined. The SNS revealed similar TPIs to the Saxon squad in all positional groups, only SNS FR were heavier (p ≤ 0.01; r = 0.18) and taller (p ≤ 0.001; r = 0.25) than Saxons FR. Likewise, the results demonstrate that anthropometrical characteristics consistently differentiated respective squads though, on occasion, there were aspects of TPIs that discriminated youth (U18) adult (U20, NA) and senior (Saxons, SNS) age international squads for the six positional groups within the EPPP. Used in isolation therefore, TPIs might offer benchmarks across the respective squads, however the extent of the observed differences between younger (U18 and U20) and older (NA, Saxons & SNS) squads suggests they could be used in conjunction with coach intuition to improve the objectivity of player selection to future squads. Where the performances of progressed and non-progressed players were considered results revealed that taller and heavier players, competing within a higher number of matches, for an increased period of time, were the most important variables influencing progression or deselection from the programme. Where the match TPIs were considered, there were stochastic differences between groups though it appeared as though selected players typically outperformed the non-selected group albeit by small margins and there were fewer differences between progressed and non-progressed in older age squads. Finally, in players selected to progress and those deselected, there was notable within-group variation in the technical demands. Such variation was typified by overlapping IQRs when groups were compared meaning selected players could perform more, or less, effectively than deselected players in any given match. Clearly, such an issue suggests that the technical performance during competition cannot be used to determine talent in such instances. Collectively, the results provide insight to the key requirements of the EPPP, which could be used to develop future coaching, scouting methods, player TDE systems by providing normative levels of attainment for aspiring players, both enrolled or not, within the elite player developmental system.
    • Risk perception as a function of risk exposure amongst rock climbers

      Martha, Cecile; Sanchez, Xavier; Gomà-i-Freixanet, Montserrat; Université de la Méditerranée ; University of Chester ; Autonomous University of Barcelona (Elsevier, 2009-01)
      This article discusses a study of 235 climbers which examined the extent to which climbers' climbing safety perceived competence and perceived own absolute and comparative risk of getting seriously injured whilst climbing is related to risk exposure.