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Walker JM, Slattery KM, Coutts AJ. The physical, technical and tactical demands of on-field training drills in professional Rugby league: a systematic scoping review. SCI MED FOOTBALL 2024:1-20. [PMID: 38940239 DOI: 10.1080/24733938.2024.2369526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 06/10/2024] [Indexed: 06/29/2024]
Abstract
OBJECTIVES The main objectives of this scoping review were to conduct a systematic search on the physical, technical and tactical demands of rugby league training, consolidate and summarise key findings and identify any existing gaps in knowledge. METHODS A systematic online search of Scopus, PubMed, MEDLINE and SPORTDiscus was conducted from earliest record to 6 August 2023 and supplemented by manually searching reference lists. The Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) Checklist was followed. Studies were eligible for inclusion if they investigated the physical, technical and/or tactical demands of rugby league training within all levels of competition and included either male or female participants. RESULTS The initial search yielded 637 papers, 25 of which were included in the review. Of these studies, the majority (n = 19) exclusively examined the physical demands of training, one paper exclusively examined the technical demands of training, five studies included both physical and technical demands, and no studies examined the tactical demands of training. Small-sided games was the most prevalent drill included within investigations examining the physical and technical demands of various rugby league training drills. CONCLUSIONS The present review was the first to scope peer-reviewed literature on the multifaceted demands (i.e. physical, technical and tactical) demands of rugby league training. It is apparent that this area is under researched, specifically in literature examining the technical and tactical elements of rugby league training.
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Affiliation(s)
- Joanne M Walker
- Faculty of Health, School of Exercise, Sport and Rehabilitation, University of Technology Sydney, Sydney, NSW, Australia
- Faculty of Health, Human Performance Research Centre, University of Technology Sydney, Sydney, NSW, Australia
| | - Katie M Slattery
- Faculty of Health, School of Exercise, Sport and Rehabilitation, University of Technology Sydney, Sydney, NSW, Australia
- Faculty of Health, Human Performance Research Centre, University of Technology Sydney, Sydney, NSW, Australia
| | - Aaron J Coutts
- Faculty of Health, School of Exercise, Sport and Rehabilitation, University of Technology Sydney, Sydney, NSW, Australia
- Faculty of Health, Human Performance Research Centre, University of Technology Sydney, Sydney, NSW, Australia
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Helme M, Emmonds S, Low C, Till K. A Novel Case Study Approach to the Investigation of Leg Strength Asymmetry and Rugby League Player's Multidirectional Speed. J Strength Cond Res 2024; 38:941-947. [PMID: 38260986 DOI: 10.1519/jsc.0000000000004712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
ABSTRACT Helme, M, Emmonds, S, Low, C, and Till, K. A novel case study approach to the investigation of leg strength asymmetry and Rugby League player's multidirectional speed. J Strength Cond Res 38(5): 941-947, 2024-Leg strength and multidirectional speed qualities have repeatedly been linked with increased performance during Rugby League (RL) match play and associated with career attainment. However, very little of this evidence for strength has been gained through unilateral measurements with no study available that has examined the impact of strength asymmetry, in this population, on speed qualities in RL players. Therefore, this study examined the association between unilateral strength, and as a novel development, the subject with the most extreme asymmetry was identified for further analysis. Fifty RL players undertook the rear foot elevated split squat 5 repetition maximum, 20-m linear sprint, and modified 505 change of direction test. The mean leg strength for the group was 88.92 ± 12.59 kg; when divided by body mass, the mean relative strength (REL) was 1.03 ± 0.17 kg·kg -1 , and the mean asymmetry was 3.21 ± 5.70%. The subject with the greatest asymmetry (subject A) had an imbalance of 33% and a mean leg strength of 75 kg (REL = 0.78 kg·kg -1 ) and a body mass 1 SD above the group mean. Analysis of the group's data and that of subject A did not indicate that leg strength asymmetry was either frequent or harmful, with respect to speed performance. However, relative leg strength was associated with both improved linear and multidirectional speed. Practitioners are recommended to prioritize the development of relative leg strength and disregard the aspiration for between leg performance symmetry.
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Affiliation(s)
- Mark Helme
- Centre for Sports Coaching, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom; and
- Carnegie Applied Rugby Research Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
| | - Stacey Emmonds
- Centre for Sports Coaching, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom; and
- Carnegie Applied Rugby Research Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
| | - Chris Low
- Centre for Sports Coaching, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom; and
| | - Kevin Till
- Centre for Sports Coaching, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom; and
- Carnegie Applied Rugby Research Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
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Parmley J, Jones B, Whitehead S, Rennie G, Hendricks S, Johnston R, Collins N, Bennett T, Weaving D. The speed and acceleration of the ball carrier and tackler into contact during front-on tackles in rugby league. J Sports Sci 2023; 41:1450-1458. [PMID: 37925647 DOI: 10.1080/02640414.2023.2273657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 10/14/2023] [Indexed: 11/07/2023]
Abstract
The aim was to use a combination of video analysis and microtechnology (10 Hz global positioning system [GPS]) to quantify and compare the speed and acceleration of ball-carriers and tacklers during the pre-contact phase (contact - 0.5s) of the tackle event during rugby league match-play. Data were collected from 44 professional male rugby league players from two Super League clubs across two competitive matches. Tackle events were coded and subject to three stages of inclusion criteria to identify front-on tackles. 10 Hz GPS data was synchronised with video to extract the speed and acceleration of the ball-carrier and tackler into each front-on tackle (n = 214). Linear mixed effects models (effect size [ES], confidence intervals, p-values) compared differences. Overall, ball-carriers (4.73 ± 1.12 m∙s-1) had greater speed into front-on tackles than tacklers (2.82 ± 1.07 m∙s-1; ES = 1.69). Ball-carriers accelerated (0.67 ± 1.01 m∙s-2) into contact whilst tacklers decelerated (-1.26 ± 1.36 m∙s-2; ES = 1.74). Positional comparisons showed speed was greater during back vs. back (ES = 0.66) and back vs. forward (ES = 0.40) than forward vs. forward tackle events. Findings can be used to inform strategies to improve performance and player welfare.
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Affiliation(s)
- James Parmley
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Ben Jones
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
- England Performance Unit, Rugby Football League, Leeds, UK
- Premiership Rugby, London, United Kingdom
- School of Science and Technology, University of New England, Armidale, NSW, Australia
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, the University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa
| | - Sarah Whitehead
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Gordon Rennie
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
- Catapult Sports, Leeds, UK
| | - Sharief Hendricks
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, the University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa
| | - Rich Johnston
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
- School of Behavioural and Health Sciences, Australian Catholic University, Brisbane, Queensland, Australia
- Sports Performance, Recovery, Injury and New Technologies (SPRINT) Research Centre, Australian Catholic University, Brisbane, QLD, Australia
| | - Neil Collins
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
- England Performance Unit, Rugby Football League, Leeds, UK
| | - Thomas Bennett
- Department of Sport, Health and Exercise Science, University of Hull, Hull, UK
- Hull F.C, Hull, UK
| | - Dan Weaving
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
- Applied Sports Science and Exercise Testing Laboratory, The University of Newcastle, Ourimbah, Australia
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Woodhouse LN, Bennett M, Tallent J, Patterson SD, Waldron M. The relationship between physical characteristics and match collision performance among elite international female rugby union players. Eur J Sport Sci 2023; 23:1849-1858. [PMID: 36336974 DOI: 10.1080/17461391.2022.2144765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This study investigated whether anthropometric and physical abilities explained variance in match collision performance among international female rugby union players. Physical performance and anthropometric data for fifty-one international female rugby union players, and collision actions categorised as "effort" or "performance" variables, from 20 international matches, were analysed using partial least squares regression. Among forwards, variance in carries/min was explained (R2 = .22) by a combination of; body mass, skinfolds, acceleration momentum and negative associations with mean aerobic speed and single-leg isometric squat relative force (SLISO/kgBM). Variance in collision dominance among forwards was explained (R2 = .21) by lower skinfolds and higher acceleration momentum, while tackles/min (R2 = .19) were explained by greater jumping power and single-leg isometric squat (SLISO). Among backs, variance in tackles/min (R2 = .54) was explained by greater bench press, SLISO and SLISO/kgBM. Variance in collision dominance among backs was explained (R2 = .23) by negative and positive associations with body mass and SLISO/kgBM, respectively. These findings suggest the development of physical characteristics, such as body mass and composition, strength and power contribute towards successful collision actions among international female rugby union players. The contribution of different physical characteristics towards collision events is dependent on position, and whether the collision event is categorised by "performance" or "effort". It is suggested that physical training programmes should reflect this level of specificity.HighlightsAmong elite female rugby union forwards, acceleration momentum, body mass and skinfolds are positively associated with winning collisions and carrying the ball into contact more frequently, whilst tackle frequency is positively associated with relative leg strength and power output.Among elite female backs, the ability to win collisions is positively associated with relative leg power output, and negatively associated with body mass. Tackle frequency is associated with maximum upper- and lower-body strength in this group.Physical characteristics account for some of the variability in collision performance, but interpretation of these findings should consider that factors such as technique during collision events may account for a larger proportion of total variance.Sports science practitioners can improve collision performance, to varying degrees, by enhancing specific gross physical characteristics, according to a player's position and the tactical role they are expected to fulfil.
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Affiliation(s)
- Luke Nicholas Woodhouse
- Faculty of Sport, Health and Applied Sciences, St Mary's University, London, UK
- Rugby Football Union, Rugby House, Twickenham Stadium, London, UK
| | - Mark Bennett
- Applied Sports Technology Exercise and Medicine (A-STEM) Centre, Swansea University, Swansea, UK
| | - Jamie Tallent
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK
- Department of Physiotherapy, Faculty of Medicine, Nursing and Health Sciences, School of Primary and Allied Health Care, Monash University, Melbourne, Australia
| | | | - Mark Waldron
- Applied Sport, Technology, Exercise and Medicine, College of Engineering, Swansea University, Swansea, UK
- School of Health and Behavioural Sciences, University of the Sunshine Coast, Queensland, Australia
- Welsh Institute of Performance Science, Swansea University, Swansea, UK
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Strength and Conditioning Practices of Brazilian Olympic Sprint and Jump Coaches. J Hum Kinet 2023; 86:175-194. [PMID: 37181261 PMCID: PMC10170547 DOI: 10.5114/jhk/159646] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Olympic coaches are likely to have adequate knowledge and implement effective training programs. This study aimed to describe and critically examine the strength and conditioning practices adopted by Brazilian Olympic sprint and jump coaches. Nineteen Olympic coaches (age: 50.2 ± 10.8 years; professional experience: 25.9 ± 13.1 years) completed a survey consisting of eight sections: 1) background information; 2) strength-power development; 3) speed training; 4) plyometrics; 5) flexibility training; 6) physical testing; 7) technology use; and 8) programming. It was noticed that coaches prioritized the development of explosiveness, power, and sprinting speed in their training programs, given the specific requirements of sprint and jump events. Nevertheless, unexpectedly, we observed: (1) large variations in the number of repetitions performed per set during resistance training in the off-season period, (2) a higher volume of resistance training prescribed during the competitive period (compared to other sports), and (3) infrequent use of traditional periodization models. These findings are probably related to the complex characteristics of modern competitive sports (e.g., congested competitive schedule) and the individual needs of sprinters and jumpers. Identification of training practices commonly used by leading track and field coaches may help practitioners and sport scientists create more effective research projects and training programs.
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McMahon JJ, Ripley NJ, Comfort P. Force Plate-Derived Countermovement Jump Normative Data and Benchmarks for Professional Rugby League Players. SENSORS (BASEL, SWITZERLAND) 2022; 22:8669. [PMID: 36433265 PMCID: PMC9696698 DOI: 10.3390/s22228669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 10/31/2022] [Accepted: 11/07/2022] [Indexed: 06/16/2023]
Abstract
The countermovement jump (CMJ) is an important test in rugby league (RL), and the force plate is the recommended assessment device, as it permits the calculation of several variables that explain jump strategy, alongside jump height. The purpose of this study was to produce normative CMJ data and objective benchmarks for professional RL forwards and backs. Normative data for jump height, modified reactive strength index, and jump momentum are provided for 121 professional RL players (66 forwards and 55 backs) who completed CMJ testing on a portable force plate during preseason training. Standardized T-scores (scaled from 0 to 100) were calculated from the respective positional group mean and standard deviation to create CMJ performance bands that were combined with a qualitative description (ranging from extremely poor to excellent) and a traffic light system to facilitate data interpretation and objective benchmark setting by RL practitioners. The jump height and modified reactive strength index benchmarks were larger for the lighter backs, whereas the jump momentum benchmarks were larger for the heavier forwards. The presented novel approach to compiling and presenting normative data and objective benchmarks may also be applied to other data (i.e., from other tests or devices) and populations.
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Affiliation(s)
- John J. McMahon
- Centre for Human Movement and Rehabilitation, University of Salford, Salford M6 6PU, UK
| | - Nicholas J. Ripley
- Centre for Human Movement and Rehabilitation, University of Salford, Salford M6 6PU, UK
| | - Paul Comfort
- Centre for Human Movement and Rehabilitation, University of Salford, Salford M6 6PU, UK
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA 6027, Australia
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7
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McMahon JJ, Lake JP, Dos'Santos T, Jones PA, Thomasson ML, Comfort P. Countermovement Jump Standards in Rugby League: What is a “Good” Performance? J Strength Cond Res 2022; 36:1691-1698. [DOI: 10.1519/jsc.0000000000003697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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8
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Identifying and reporting position-specific countermovement jump outcome and phase characteristics within rugby league. PLoS One 2022; 17:e0265999. [PMID: 35333887 PMCID: PMC8956158 DOI: 10.1371/journal.pone.0265999] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/14/2022] [Indexed: 11/19/2022] Open
Abstract
The countermovement jump (CMJ) has been suggested to be an important test of neuromuscular performance for rugby league (RL) players. Identifying force platform-derived CMJ variables that may be more applicable to RL positions (e.g., forwards and backs) has yet to be fully explored in the scientific literature. The aim of this study was to identify RL position-specific CMJ force-time variables. Specifically, we aimed to compare select force-time variables from the countermovement (i.e., the combination of unweighting and braking) and propulsion phases of the CMJ between the global forwards and backs positional groups. We also aimed to compare typical (i.e., jump height) and alternative (i.e., take-off momentum) outcome CMJ variables between positional groups. Finally, we sought to visually present each individual player’s CMJ performance alongside the average data to facilitate the interpretation and reporting of the CMJ performances of RL athletes. Twenty-seven forwards and twenty-seven backs who competed in the senior men’s English RL Championship, performed three CMJs on a force platform at the beginning of the pre-season training period. There were no significant differences in any countermovement or propulsion phase variable between positions with just small effect sizes noted (P ≥0.09, d ≤0.46). Jump height (and so take-off velocity) was significantly greater for backs with moderate effects displayed (P = 0.03, d = 0.60). Take-off momentum (take-off velocity × body mass) was largely and significantly greater for forwards (P<0.01, d = 1.01). There was considerable overlap of individual player’s body mass and CMJ outcome variables across positions, despite significant differences in the mean values attained by each positional group. The results suggest that it may be beneficial for RL practitioners to identify player-specific, or at least position-specific, variables. As a minimum, it may be worthwhile selecting CMJ force-time variables based on what is considered important to individual player’s or small clusters of similar players’ projected successes during RL competition.
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Effects of the Off-Season on Muscular Power in Professional Rugby League. Int J Sports Physiol Perform 2022; 17:733-738. [PMID: 35203053 DOI: 10.1123/ijspp.2021-0238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 09/15/2021] [Accepted: 10/18/2021] [Indexed: 11/18/2022]
Abstract
PURPOSE Periods away from training and competition are necessary for physical and mental restoration in sport. There is limited research investigating changes to physical qualities in rugby league following prolonged breaks. This study aimed to evaluate the effects of the off-season on muscular power in rugby league. In addition, this study aimed to determine whether the type and volume of training players chose to complete had any relationship to feelings of restoration and/or readiness to return to training. METHODS Twenty professional rugby league players participated in this study. Lower-body muscular power was evaluated using a countermovement jump prior to the off-season and at the recommencement of training. Players completed a questionnaire to identify training and activities completed during the break and to assess feelings of restoration and readiness to commence training. Linear regression was used to estimate the effects of the number of days off on muscular power. One-way repeated-measures analysis of variance was conducted to examine differences in lower-body power throughout the study. Spearman rank order correlation was calculated to determine the relationship between off-season activities and feelings of restoration and readiness. RESULTS Peak velocity and peak force significantly increased following the off-season break. There were significant relationships between mental restoration and upper-body resistance training, as well as physical restoration and full-body resistance training. CONCLUSIONS The off-season has a positive effect on a player's ability to generate muscular power. Coaches may want to encourage players to complete resistance training sessions with the aim simply to maintain training load and potentially help players to feel rested.
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10
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McMahon JJ, Jones PA, Comfort P. Comparison of Countermovement Jump-Derived Reactive Strength Index Modified and Underpinning Force-Time Variables Between Super League and Championship Rugby League Players. J Strength Cond Res 2022; 36:226-231. [PMID: 31714454 DOI: 10.1519/jsc.0000000000003380] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/20/2023]
Abstract
ABSTRACT McMahon, JJ, Jones, PA, and Comfort, P. Comparison of countermovement jump-derived reactive strength index modified and underpinning force-time variables between super league and championship rugby league players. J Strength Cond Res 36(1): 226-231, 2022-The countermovement jump (CMJ) is regularly tested in rugby league (RL), with recent work reporting reactive strength index modified (RSImod) to distinguish between levels of play. Differences in CMJ-derived RSImod and underpinning force-time variables between English Super League (SL) and RL Championship (RLC) players are, however, unknown. As SL and RLC teams compete against each other, this study addressed this knowledge gap. Sixty RL players from the English SL (n = 30) and RLC (n = 30) performed 3 CMJs on a force platform at the start of the preseason training. The RSImod was calculated by dividing jump height (JH) by time to take-off (TTT), and several other variables were also extracted from the force-time record. The SL players achieved a significantly higher (large effect) RSImod by performing the CMJ with a significantly shorter (large effect) TTT but a similar (small effect) JH. The SL players achieved the shorter TTT through a significantly reduced (large effects) relative displacement during both the countermovement (combined unweighting and braking displacement) and propulsion phases but a significantly higher (moderate effects) propulsion peak force and power. The relationships between TTT and relative countermovement (r = 0.719, p < 0.001) and propulsion (r = 0.771, p < 0.001) displacement for combined group data were very large. Practitioners working in RL should, therefore, consider reporting RSImod and TTT, alongside JH, after CMJ force-time testing. We also suggest that RL players who produce lower RSImod scores would benefit from being trained to produce larger CMJ propulsion forces over a shallower range of hip, knee, and ankle extension.
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Affiliation(s)
- John J McMahon
- Directorate of Psychology and Sport, University of Salford, Salford, Greater Manchester, United Kingdom
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11
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Redman KJ, Kelly VG, Beckman EM. Seasonal Changes in Strength and Power in Elite Rugby League: A Systematic Review and Meta-Analysis. J Sports Sci Med 2021; 20:721-731. [PMID: 35321143 PMCID: PMC8488825 DOI: 10.52082/jssm.2021.721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 08/03/2021] [Indexed: 06/14/2023]
Abstract
The ability of a rugby league player to express high levels of strength and power is crucial for success in competition. Although researchers have shown relationships between physical attributes and performance, there is a lack of information related to changes in strength and power across various phases of the season. The purpose of this review was to identify the magnitude of change in muscular strength and power during different phases of an elite rugby league season. Percentage change and effect size were calculated to evaluate the magnitude of changes in strength and power. Meta-analyses were conducted to provide pooled estimates and 95% confidence intervals. Twelve studies were included; six reported changes following pre-season training, two during the competition phase and four examined changes over multiple seasons. Pooled estimates indicated large increases in upper and lower body strength 0.81 [0.43-1.19] and 1.35 [0.79-1.91], respectively, following pre-season training. Studies incorporating predominantly heavier loads (p 80% 1 RM) in training reported greater increases in maximal strength than studies completing lighter loads. Four studies used a wave-like programming strategy to obtain large improvements in strength and power 0.91 [0.36-1.45] and 0.90 [0.22-1.57], over multiple seasons. The results of this review highlight the limited current evidence and provides a preliminary reference point for strength and conditioning coaches aiming to develop and maintain strength and power across various stages, and over multiple seasons. Importantly, the results also indicate that higher loads result in greater increases in strength than lower loads.
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Affiliation(s)
- Kellyanne J Redman
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia
- Performance Science Department, Brisbane Broncos Rugby League Club, Brisbane, Australia
| | - Vincent G Kelly
- School of Exercise and Nutrition Sciences Queensland University of Technology Brisbane, Australia
| | - Emma M Beckman
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia
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12
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Predicting Rugby League Tackle Outcomes Using Strength and Power Principal Components. Int J Sports Physiol Perform 2021; 17:278-285. [PMID: 34853184 DOI: 10.1123/ijspp.2021-0075] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 05/10/2021] [Accepted: 06/20/2021] [Indexed: 11/18/2022]
Abstract
PURPOSE Tackling is a fundamental skill in collision sports such as rugby league. Given the complexity of tackling and multitude of strength and power variables available for analysis, this study aimed to predict tackle outcomes in professional rugby league based on strength and power principal components (PCs). METHODS Twenty-eight rugby league players participated in this study. Maximal strength was assessed via 1 repetition maximum on the back squat, bench press, and bench pull. Lower-body vertical and horizontal power were evaluated using a countermovement jump and standing broad jump. A postmatch analysis of 5 National Rugby League matches was conducted to examine tackling outcomes. PC analysis was performed on the strength and power assessments. The first PCs were retained in each analysis, and a series of Spearman rank-order correlations were conducted between the tackle outcomes and the retained PCs. The PCs significantly related to tackle outcomes were included in the multiple regression analyses to estimate their effect on tackle outcomes. RESULTS Strength PC was a significant predictor of play-the-ball speed in attack, accounting for 54% of the variance. Countermovement jump PC was a significant predictor of postcontact meters, explaining 19% of the variance. CONCLUSIONS These findings demonstrate that a range of tackle outcomes may be predicted from strength and power components. The coaching staff may choose to develop programs and testing designed to focus on these components, which may further develop players' tackle outcomes during competition.
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Scott TJ, Sanctuary CE, Tredrea MS, Gray AJ. Conceptualising Rugby League Performance Within an Ecological Dynamics Framework: Providing Direction for Player Preparation and Development. SPORTS MEDICINE - OPEN 2021; 7:87. [PMID: 34817742 PMCID: PMC8613325 DOI: 10.1186/s40798-021-00375-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 10/30/2021] [Indexed: 11/28/2022]
Abstract
Across team sports, it is critically important to appropriately define, evaluate and then aptly describe individual and team performance. This is of particular significance when we consider that performance models govern the direction of player preparation (short term) and development (long term) frameworks. Within the context of rugby league, this has traditionally been undertaken through hierarchical and linear processes. Such approaches have resulted in research and performance analysis techniques which aim to support these operational outcomes. Yet, these methods may deliver limited application on how or why match-play unfolds and therefore might be sub-optimal in providing insights to truly support coaches. In this paper, we propose the conceptualisation of rugby league performance through the lens of ecological dynamics, which may offer a different view to this traditional approach. We propose that this approach eliminates the silos of disciplinary information (e.g. technical, physical and medical) that may currently exist, allowing for a holistic approach to performance, preparation and development. Specifically, we consider that through the implementation of this ecological approach, all performance coaches (technical, physical and medical) may (co-)design learning environments that more collaboratively develop players for rugby league match-play. As a result, we put forward a new rugby league performance model from which preparation and development programs can be anchored toward. We conclude the paper by offering practical examples where these concepts are contextualised within the landscape familiar to practitioners working within rugby league.
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Affiliation(s)
- Tannath J Scott
- Performance Department, New South Wales Rugby League, Sydney, Australia.
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK.
- School of Science and Technology, University of New England, Armidale, NSW, Australia.
| | - Colin E Sanctuary
- Performance Department, New South Wales Rugby League, Sydney, Australia
- School of Education, University of Newcastle, Newcastle, Australia
| | - Matthew S Tredrea
- Performance Department, New South Wales Rugby League, Sydney, Australia
- Discipline of Sport and Exercise Science, School of Allied Health, Human Services and Sport, La Trobe University, Melbourne, Australia
| | - Adrian J Gray
- School of Health and Behavioural Sciences, University of Sunshine Coast, Sunshine Coast, Australia
- College of Engineering, Swansea University, Swansea, UK
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14
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Redman KJ, Wade L, Whitley R, Connick MJ, Kelly VG, Beckman EM. The Relationship Between Match Tackle Outcomes and Muscular Strength and Power in Professional Rugby League. J Strength Cond Res 2021; 36:2853-2861. [PMID: 33470597 DOI: 10.1519/jsc.0000000000003940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Redman, KJ, Wade, L, Whitley, R, Connick, MJ, Kelly, VG, and Beckman, EM. The relationship between match tackle outcomes and muscular strength and power in professional rugby league. J Strength Cond Res XX(X): 000-000, 2020-Tackling is a fundamental skill in collision sports, such as rugby league. Match success is largely dependent on a player's ability to complete tackles and tolerate physical collisions. High levels of strength and power are key physical qualities necessary for effective tackling because players are required to generate large forces while pushing and pulling their opponents. The aim of this study was to examine the relationship between tackle outcomes and strength and power qualities in professional rugby league. Fourteen rugby league players participated in this study. Maximal strength was assessed through 1 repetition maximum on the back squat, bench press, and bench pull. Lower-body vertical and horizontal powers were evaluated using a countermovement jump and standing broad jump (SBJ), respectively. Upper-body power was assessed on a plyometric push-up (PPU). Postmatch analysis of 5 National Rugby League matches was conducted to examine tackling outcomes. A series of Spearman's rank-order correlations were used to assess the relationship among match tackle outcomes and strength and power variables. Significant associations were observed between play-the-ball speed and SBJ peak power (rs = -0.74, p = 0.003), postcontact metres and PPU peak power (rs = 0.77, p = 0.002), losing the play-the-ball contest in defence with SBJ distance (rs = 0.70, p = 0.006), and ineffective tackles with PPU concentric impulse (rs = 0.70, p = 0.007). These results suggest the development and maintenance of full-body power to enhance the likelihood of positive tackle outcomes during professional rugby league match-play.
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Affiliation(s)
- Kellyanne J Redman
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia; Performance Science Department, Brisbane Broncos Rugby League Club, Brisbane, Australia; Center for the Analysis of Motion, Entertainment Research and Applications, Department for Health, The University of Bath, Bath, United Kingdom; and School of Exercise and Nutrition Sciences Queensland University of Technology Brisbane, Brisbane, Australia
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15
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McMahon JJ, Lake JP, Ripley NJ, Comfort P. Vertical Jump Testing in Rugby League: A Rationale for Calculating Take-Off Momentum. J Appl Biomech 2020; 36:370-374. [PMID: 32796137 DOI: 10.1123/jab.2020-0100] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/14/2020] [Accepted: 06/05/2020] [Indexed: 10/27/2023]
Abstract
The purpose of this study was to determine the usefulness of calculating jump take-off momentum in rugby league (RL) by exploring its relationship with sprint momentum, due to the latter being an important attribute of this sport. Twenty-five male RL players performed 3 maximal-effort countermovement jumps on a force platform and 3 maximal effort 20-m sprints (with split times recorded). Jump take-off momentum and sprint momentum (between 0 and 5, 5 and 10, and 10 and 20 m) were calculated (mass multiplied by velocity) and their relationship determined. There was a very large positive relationship between both jump take-off and 0- to 5-m sprint momentum (r = .781, P < .001) and jump take-off and 5- to 10-m sprint momentum (r = .878, P < .001). There was a nearly perfect positive relationship between jump take-off and 10- to 20-m sprint momentum (r = .920, P < .001). Jump take-off and sprint momentum demonstrated good-excellent reliability and very large-nearly perfect associations (61%-85% common variance) in an RL cohort, enabling prediction equations to be created. Thus, it may be practically useful to calculate jump take-off momentum as part of routine countermovement jump testing of RL players and other collision-sport athletes to enable the indirect monitoring of sprint momentum.
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Affiliation(s)
| | | | | | - Paul Comfort
- University of Salford
- Leeds Beckett University
- Edith Cowan University
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16
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Cummins C, Charlton G, Naughton M, Jones B, Minahan C, Murphy A. The Validity of Automated Tackle Detection in Women's Rugby League. J Strength Cond Res 2020; 36:1951-1955. [PMID: 32956263 DOI: 10.1519/jsc.0000000000003745] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cummins, C, Charlton, G, Naughton, M, Jones, B, Minahan, C, and Murphy, A. The validity of automated tackle detection in women's rugby league. J Strength Cond Res XX(X): 000-000, 2020-This study assessed the validity of microtechnology devices to automatically detect and differentiate tackles in elite women's rugby league match-play. Elite female players (n = 17) wore a microtechnology device (OptimEye S5 device; Catapult Group International) during a representative match, which involved a total of 512 tackles of which 365 were defensive and 147 were attacking. Tackles automatically detected by Catapult's tackle detection algorithm and video-coded tackles were time synchronized. True positive, false negative and false positive events were utilized to calculate sensitivity (i.e., when a tackle occurred, did the algorithm correctly detect this event) and precision (i.e., when the algorithm reported a tackle, was this a true event based on video-coding). Of the 512 video-derived attacking and defensive tackle events, the algorithm was able to detect 389 tackles. The algorithm also produced 81 false positives and 123 false negatives. As such when a tackle occurred, the algorithm correctly identified 76.0% of these events. When the algorithm reported that a tackle occurred, this was an actual event in 82.8% of circumstances. Across all players, the algorithm was more sensitive to the detection of an attacking event (sensitivity: 78.2%) as opposed to a defensive event (sensitivity: 75.1%). The sensitivity and precision of the algorithm was higher for forwards (sensitivity: 81.8%; precision: 92.1%) when compared with backs (sensitivity: 64.5%; precision: 66.1%). Given that understanding the tackle demands of rugby league is imperative from both an injury-prevention and physical-conditioning perspective there is an opportunity to develop a specific algorithm for the detection of tackles within women's rugby league.
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Affiliation(s)
- Cloe Cummins
- School of Science and Technology, University of New England, Armidale, NSW, Australia.,Carnegie Applied Rugby Research (CARR) Center, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom.,National Rugby League, Australia
| | - Glen Charlton
- School of Science and Technology, University of New England, Armidale, NSW, Australia
| | - Mitchell Naughton
- School of Science and Technology, University of New England, Armidale, NSW, Australia
| | - Ben Jones
- School of Science and Technology, University of New England, Armidale, NSW, Australia.,Carnegie Applied Rugby Research (CARR) Center, Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom.,Leeds Rhinos Rugby League Club, Leeds, United Kingdom.,Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, the University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa.,England Performance Unit, the Rugby Football League, Leeds, United Kingdom
| | - Clare Minahan
- Griffith Sports Science, Griffith University, Gold Coast, Australia
| | - Aron Murphy
- School of Science and Technology, University of New England, Armidale, NSW, Australia
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17
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Simpson A, Waldron M, Cushion E, Tallent J. Optimised force-velocity training during pre-season enhances physical performance in professional rugby league players. J Sports Sci 2020; 39:91-100. [PMID: 32799729 DOI: 10.1080/02640414.2020.1805850] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The effectiveness of 8-week force-velocity optimised training was assessed in highly trained professional rugby league athletes. Players (age 24 ± 3 years; body mass 94.9 ± 21.6 kg; height 181.3 ± 6.0 cm) were strength-matched and assigned to a force-velocity optimised group (OP; n = 15) or a general strength-power group (GP; n = 14). Tests included 10-m, 20-m sprints, 3 repetition-maximum squat and squat jumps over five load conditions to ascertain vertical force-velocity relationship. ANCOVA revealed there was a group effect for force-velocity deficit (P < 0.001), with the OP two-fold greater than the GP group (OP pre: 51.13 ± 31.42%, post: 62.26 ± 31.45%, GP pre: 33.00 ± 19.60%, post: 31.14 ± 31.45%, P < 0.001). There were further group effects for 3RM squat (OP pre: 151.17 ± 22.95 kg, post: 162.17 ± 24.16 kg, GP pre: 156.43 ± 25.07 kg, post: 163.39 ± 25.39 kg, P < 0.001), peak power (OP pre: 3195 ± 949 W, post: 3552 ± 1033 W, GP pre: 3468 ± 911 W, post: 3591 ± 936 W, P < 0.001), and SJ (OP pre: 39.79 ± 7.80 cm, post: 42.69 ± 7.83 cm, GP pre: 40.44 ± 6.23 cm, post: 41.14 ± 5.66 cm, P < 0.001). Prescribing F-V deficit training is superior for improving physical performance within highly trained RL players.
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Affiliation(s)
- Adam Simpson
- School of Sport, Health and Applied Science, St Marys University , Twickenham, UK.,Bradford Bulls RLFC , Bradford, UK
| | - Mark Waldron
- Research Centre in Applied Sports, Technology, Exercise and Medicine, College of Engineering, Swansea University , Swansea, Wales.,School of Science and Technology, University of New England , Armidale, Australia
| | - Emily Cushion
- School of Sport, Health and Applied Science, St Marys University , Twickenham, UK
| | - Jamie Tallent
- School of Sport, Health and Applied Science, St Marys University , Twickenham, UK
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18
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Brazier J, Antrobus M, Stebbings GK, Day SH, Callus P, Erskine RM, Bennett MA, Kilduff LP, Williams AG. Anthropometric and Physiological Characteristics of Elite Male Rugby Athletes. J Strength Cond Res 2020; 34:1790-1801. [DOI: 10.1519/jsc.0000000000002827] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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19
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Richardson E, Lewis JS, Gibson J, Morgan C, Halaki M, Ginn K, Yeowell G. Role of the kinetic chain in shoulder rehabilitation: does incorporating the trunk and lower limb into shoulder exercise regimes influence shoulder muscle recruitment patterns? Systematic review of electromyography studies. BMJ Open Sport Exerc Med 2020; 6:e000683. [PMID: 32405430 PMCID: PMC7202723 DOI: 10.1136/bmjsem-2019-000683] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/08/2020] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE To investigate the influence of trunk and lower limb motion on electromyography (EMG) muscle activity and recruitment patterns around the shoulder. DESIGN Systematic review. DATA SOURCES MEDLINE, CINAHL, PEDro, AMED, PubMed, Cochrane Central Register of Controlled trials, Cochrane Database of Systematic reviews, SportsDiscuss and PROSPERO. ELIGIBILITY CRITERIA Studies investigating both multiregional kinetic chain (KC) shoulder exercises and localised non-kinetic chain (nKC) shoulder exercises in healthy subjects under the same experimental conditions were included in this review. RESULTS KC exercises produced greater EMG activation levels in 5 of 11 studies for the lower trapezius. Of the remaining studies, five found no difference between the exercise types and one favoured nKC exercises. KC exercises produced greater EMG activation levels in 5 of 11 studies for the serratus anterior. Of the remaining studies, three reported the opposite and three found no significant difference between the exercise types. nKC exercises produced greater EMG activation in infraspinatus in three of four studies. KC exercises produced the lowest trapezius muscle ratios in all studies. Studies investigating the upper trapezius, middle trapezius, supraspinatus, subscapularis, biceps brachii, latifissimus dorsi, pectoralis major, deltoid, and trapezius and serratus anterior ratios showed inconsistency. CONCLUSION This review found evidence that integrating the KC during shoulder rehabilitation may increase axioscapular muscle recruitment, produce lower trapezius muscle ratios and reduce the demands on the rotator cuff. Stepping appears preferable to squatting. PROSPERO REGISTRATION NUMBER CRD42015032557, 2015.
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Affiliation(s)
- Eleanor Richardson
- Department of Physiotherapy, BMI The Alexandra Hospital, Cheadle, UK
- Faculty of Health Psychology and Social Care, Manchester Metropolitan University, Didsbury, Manchester, UK
| | - Jeremy S Lewis
- School of Health and Social Work, University of Hertfordshire, Hatfield, Hertfordshire, UK
- Therapy Department London, Central London Community Healthcare NHS Trust, London, UK
- Department of Physical Therapy and Rehabilitation Sciences, Qatar University, Doha, Qatar
| | - Jo Gibson
- Department of Physiotherapy, Royal Liverpool and Broadgreen Hospitals NHS Trust, Liverpool, UK
- The School of Health Sciences, University of Liverpool, Liverpool, UK
| | - Chris Morgan
- High Performance Unit, Medical Department, Arsenal Football Club, London, UK
| | - Mark Halaki
- Faculty of Health Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Karen Ginn
- Faculty of Health Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Gillian Yeowell
- Faculty of Health Psychology and Social Care, Manchester Metropolitan University, Didsbury, Manchester, UK
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20
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Ungureanu AN, Condello G, Pistore S, Conte D, Lupo C. Technical and Tactical Aspects in Italian Youth Rugby Union in Relation to Different Academies, Regional Tournaments, and Outcomes. J Strength Cond Res 2019; 33:1557-1569. [PMID: 28820858 DOI: 10.1519/jsc.0000000000002188] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Ungureanu, AN, Condello, G, Pistore, S, Conte, D, and Lupo, C. Technical and tactical aspects in Italian youth rugby union in relation to different academies, regional tournaments, and outcomes. J Strength Cond Res 33(6): 1557-1569, 2019-This study aimed to analyze the technical and tactical aspects of the Italian under-18 Academy Rugby Union in relation to different academies, regional tournaments, and game outcomes. A notational analysis (44 indicators) was performed on 16 games (2014-15 season) to evaluate strong differences (p ≤ 0.05; moderate-large effect sizes [ESs]) according to variables. Among academies, strong differences were showed for defensive breakdown, in which the defending support is much (range = 77-87%), equal (range = 11-32%), and less (range = 2-12%) numerous than the attacking support, total tackles (range = 64-122), and passes (range = 72-151), pass to possession ratio (range = 6-10), possession lost due to an error (range = 28-59%), and ball in play in own (range = 8-25%) and opponent (range = 7-31%) 22-m area indicators. For tournaments, effects emerged for offensive breakdown when the ball is used quickly using maximum 2 attacking supports (range = 20-30%) and is not used quickly (range = 28-41%), total penalty kicks (range = 11-16), and sequences period 0-10 (range = 26-35%) and 10-40 seconds (range = 47-55%). Conversely, winning and losing academies reported differences with small ESs. These results highlight that the technical and tactical aspects of the Italian under-18 Academy Rugby Union are quite homogeneous, suggesting that FIR coaching staffs are more oriented to players' skills than successful games. However, tactical and strength and conditioning coaches can benefit from the findings of this study, focusing training on cognitive, strength, and repeated sprint abilities with and without change of direction for improving the occurrence of "set pieces won/regained" and "ball in play in opponent 22 m area," which appear as the key of the game in this rugby competition level.
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Affiliation(s)
- Alexandru N Ungureanu
- Department of Medical Sciences, NeuroMuscularFunction Research Group, School of Exercise and Sport Sciences (SUISM), University of Torino, Turin, Italy.,Italian Rugby Federation (FIR), Rome, Italy
| | - Giancarlo Condello
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, Rome, Italy
| | | | - Daniele Conte
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, Rome, Italy.,Institute of Sport Science and Innovations, Lithuanian Sports University, Kaunas, Lithuania
| | - Corrado Lupo
- Department of Medical Sciences, NeuroMuscularFunction Research Group, School of Exercise and Sport Sciences (SUISM), University of Torino, Turin, Italy
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21
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den Hollander S, Lambert M, Jones B, Hendricks S. Tackle and ruck technique proficiency within academy and senior club rugby union. J Sports Sci 2019; 37:2578-2587. [DOI: 10.1080/02640414.2019.1648121] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Steve den Hollander
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, the University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa
- Health through Physical Activity, Lifestyle and Sport Research Centre (HPALS), Faculty of Health Sciences, the University of Cape Town, Cape Town, South Africa
- Western Province Rugby Academy, Cape Town, South Africa
| | - Michael Lambert
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, the University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa
- Western Province Rugby Academy, Cape Town, South Africa
| | - Ben Jones
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, the University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa
- Carnegie Applied Rugby Research (CARR) Centre, Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK
- Yorkshire Carnegie Rugby Union Football Club, Leeds, UK
- Leeds Rhinos Rugby League Club, Leeds, UK
- England Performance Unit, The Rugby Football League, Leeds, UK
| | - Sharief Hendricks
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, the University of Cape Town and the Sports Science Institute of South Africa, Cape Town, South Africa
- Western Province Rugby Academy, Cape Town, South Africa
- Carnegie Applied Rugby Research (CARR) Centre, Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK
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22
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The Use of Microtechnology to Monitor Collision Performance in Professional Rugby Union. Int J Sports Physiol Perform 2018; 13:1075-1082. [DOI: 10.1123/ijspp.2017-0124] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Purpose: To determine if microtechnology-derived collision loads discriminate between collision performance and compare the physical and analytical components of collision performance between positional groups. Methods: Thirty-seven professional male rugby union players participated in this study. Collision events from 11 competitive matches were coded using specific tackle and carry classifications based on the ball-carrier’s collision outcome. Collisions were automatically detected using 10 Hz microtechnology units. Collision events were identified, coded (as tackle or carry), and timestamped at the collision contact point using game analysis software. Attacking and defensive performances of 1609 collision events were analyzed. Results: Collision loads were significantly greater during dominant compared with neutral and passive collisions (P < .001; effect size [ES] = 0.53 and 0.80, respectively), tackles (P < .0001; ES = 0.60 and 0.56, respectively), and carries (P < .001; ES = 0.48 and 0.79, respectively). Overall, forwards reported a greater number and frequency of collisions but lower loads per collision and velocities at collision point than did backs. Microtechnology devices can also accurately, sensitively, and specifically identify collision events (93.3%, 93.8%, and 92.8%, respectively). Conclusion: Microtechnology is a valid means of discriminating between tackle and carry performance. Thus, microtechnology-derived collision load data can be utilized to track and monitor collision events in training and games.
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23
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Loturco I, Pereira LA, Kobal R, McGuigan MR. Power output in traditional and ballistic bench press in elite athletes: Influence of training background. J Sports Sci 2018; 37:277-284. [PMID: 29983101 DOI: 10.1080/02640414.2018.1496517] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
This study aimed to compare the power production in traditional bench-press (TBP) and ballistic bench-throw (BBT) exercises. Furthermore, we assessed the differences in velocity, force, and power outputs between TBP and BBT. Finally, we tested the differences between the loads used to optimize power (optimum power load; OPL) in both exercises, using three distinct power-variables: mean power (MP), mean propulsive power (MPP), and peak power (PP). Sixty athletes from different sports were divided into two groups, according to their training characteristics: hypertrophy-based trained athletes (HTA), thirty-one athletes performing hypertrophy training programmes for (at least) 12-weeks; and power-based trained athletes (PTA), twenty-nine athletes performing power-oriented training sessions for (at least) 12-weeks. Magnitude-based inferences were used to test for differences between groups. Independent of the variable analyzed (MP, MPP, or PP), the PTA produced greater power values in BBT, whereas the HTA generated higher outputs during TBP. The OPL in the HTA was likely heavier in TBP than in BBT, whereas no differences related to this variable were found in the PTA. Despite the apparent superiority of ballistics to produce power, it seems that in elite athletes, the strength-power training routine might affect the ability to apply high forces at very-high velocities.
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Affiliation(s)
- Irineu Loturco
- a NAR - Nucleus of High Performance in Sport , São Paulo , Brazil
| | - Lucas A Pereira
- a NAR - Nucleus of High Performance in Sport , São Paulo , Brazil
| | - Ronaldo Kobal
- a NAR - Nucleus of High Performance in Sport , São Paulo , Brazil
| | - Michael R McGuigan
- b Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology , Auckland , New Zealand.,c School of Medical and Health Sciences, Edith Cowan University , Perth , Australia
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24
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Relationship Between 2 Standardized Tackling Proficiency Tests and Rugby League Match-Play Tackle Performance. Int J Sports Physiol Perform 2018; 13:770-776. [PMID: 29140179 DOI: 10.1123/ijspp.2017-0593] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study investigated the relationship between 2 different assessments of tackling ability, physical qualities, and match-play performance in semiprofessional rugby league players. A total of 18 semiprofessional rugby league players (mean [SD]: age = 23.1 [2.0] y and body mass = 98.8 [11.8] kg) underwent tests of upper- and lower-body strength and power. Tackling ability was assessed using video analysis of under- and over-the-ball tackle drills. A total of 2360 tackles were analyzed from match play. Over-the-ball tackle ability was positively related to the proportion of dominant tackles (Spearman rank-order correlation coefficients [rs] = .52; 95% confidence interval [CI] .07-.79, P = .03) and average play-the-ball speeds (rs = .50; 95% CI .04-.78, P = .03) and negatively related to tackles that conceded offloads (rs = -.55; 95% CI -.78 to .04, P = .04). Under-the-ball tackle ability was significantly related to the proportion of dominant tackles (rs = .57; 95% CI .14-.82, P = .01) and missed tackles (rs = -.48; 95% CI -.77 to .02, P = .05). Good over-the-ball tacklers performed proportionally more dominant tackles, allowed significantly fewer offloads, and had longer average play-the-ball speeds. Good under-the-ball tacklers missed proportionately fewer tackles. This study suggests that both the under-the-ball and over-the-ball standardized tackle assessments are associated with varying indicators of match-play tackle performance and justifies the practical utility of these tests to assess and develop both types of tackles.
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25
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Burger N, Lambert MI, Hall H, Hendricks S. Assessing tackle performance using a novel collision sport simulator in comparison to a "live" one-on-one tackling drill. J Sports Sci 2018; 37:74-81. [PMID: 29889607 DOI: 10.1080/02640414.2018.1482590] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
It is necessary to study the rugby tackle as it is associated with successful performance outcomes and is responsible for the majority of contact injuries. A novel collision sport simulator was developed to study tackle performance. The main aim of this validation study was to assess tackle technique performance between two different conditions: simulator versus a standardised one-on-one tackle drill previously used to assess technique. Tackling proficiency was assessed using a list of technical criteria. Mean scores, standard deviations and Cohen's d effect sizes were calculated. Mean overall score for dynamic i.e. running simulator tackles was 7.78 (95%CI 7.58-7.99) (out of 9) or 87% (standard deviation or SD±8.94), and mean overall score for dynamic "live" tackles was 7.85 (95%CI 7.57-8.13) (out of 9) or 87% (SD±9.60) (effect size = 0.08; trivial; p > 0.05). Mean overall score for static i.e. standing simulator tackles was 7.45 (95%CI 7.20-7.69) (out of 9) or 83% (SD±10.71), and mean overall score for static "live" tackles was 8.05 (95%CI 7.83-8.27) (out of 9) or 89% (SD±7.53) (effect size = 0.72; moderate; p < 0.001). The simulator replicates dynamic tackle technique comparable to real-life tackle drills. It may be used for research analysing various aspects of the tackle in rugby and other contact sports.
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Affiliation(s)
- Nicholas Burger
- a Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences , University of Cape Town , Cape Town , South Africa
| | - Michael Ian Lambert
- a Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences , University of Cape Town , Cape Town , South Africa.,b Department of Public & Occupational Health and the EMGO Institute for Health and Care Research , VU University Medical Center , Amsterdam , The Netherlands
| | - Harry Hall
- a Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences , University of Cape Town , Cape Town , South Africa
| | - Sharief Hendricks
- a Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences , University of Cape Town , Cape Town , South Africa.,c Institute for Sport, Physical Activity and Leisure, Centre for Sport Performance, School of Sport, Fairfax Hall, Headingley Campus , Leeds Beckett University , Leeds , United Kingdom
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26
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Portillo J, Del Coso J, Abián-Vicén J. Effects of Caffeine Ingestion on Skill Performance During an International Female Rugby Sevens Competition. J Strength Cond Res 2018; 31:3351-3357. [PMID: 28002181 DOI: 10.1519/jsc.0000000000001763] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Portillo, J, Del Coso, J, and Abián-Vicén, J. Effects of caffeine ingestion on skill performance during an international female rugby sevens competition. J Strength Cond Res 31(12): 3351-3357, 2017-The aim of this study was to establish the effects of a caffeine-containing energy drink on skills and technical performance during a match in female elite rugby sevens players. On 2 nonconsecutive days of a friendly tournament, 16 women from the Spanish national rugby sevens team (mean age = 23 ± 2 years) ingested 3 mg of caffeine per kilogram of body mass in the form of an energy drink or the same drink without caffeine (placebo drink). After 60 minutes for caffeine absorption, participants played 3 rugby sevens matches against another national team. Body impacts during the matches were assessed by triaxial accelerometers. The matches were videotaped, and each individual technical action was notated afterward by 2 experienced observers. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased the rate of body impacts in zone 1 (16.1 ± 4.9 vs. 20.8 ± 9.9 impacts/min, p < 0.05), zone 2 (12.2 ± 10.6 vs. 16.2 ± 15.2 impacts/min, p < 0.05), zone 3 (3.8 ± 1.5 vs. 4.7 ± 2.6 impacts/min, p < 0.05), and zone 5 (0.8 ± 0.4 vs. 1.1 ± 0.6 impacts/min, p < 0.05). The pre-exercise ingestion of the caffeinated energy drink did not affect the frequency or the quality of any rugby-specific technical actions during the games. In conclusion, the ingestion of 3 mg·kg of caffeine in the form of an energy drink increased the number of body impacts during a rugby sevens international competition which suggests a higher engagement of the players during the game. However, the caffeine ingestion did not influence the quality of the technical actions performed during the competition.
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Affiliation(s)
- Javier Portillo
- Faculty of Sport Sciences, Performance and Sport Rehabilitation Laboratory, University of Castilla-La Mancha, Toledo, Spain
| | - Juan Del Coso
- Exercise Physiology Laboratory, Camilo José Cela University, Madrid, Spain
| | - Javier Abián-Vicén
- Faculty of Sport Sciences, Performance and Sport Rehabilitation Laboratory, University of Castilla-La Mancha, Toledo, Spain
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27
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Abstract
This study investigated the relationship between 2 tests of tackling ability, muscle strength, and power in semiprofessional rugby league players. Thirty-one players, 19 first-grade and 12 second-grade, underwent tests of muscle strength (1-repetition-maximum bench press, chin-up, and squat) and power (plyometric push-up and countermovement jump). Tackling ability was assessed via video analysis of under-and over-the-ball tackle drills. The first-grade players had significantly greater scores in both the under-the-ball (P = .03, effect size [ES] = 0.84, 95% CI 0.07–1.50) and over-the-ball tackling-ability tests (P < .001, ES =1.86, 95% CI 0.83–2.52) than the second-grade players. A large, significant relationship was found between under- and over-the-ball tackling ability (r = .55, 95% CI .24–.76, P = .001). Lower-body strength (r = .37, 95% CI .02–.64, P = .04) was moderately associated with under-the-ball tackling ability, whereas over-the-ball tackling ability was moderately associated with plyometric push-up performance (r = .39, 95% CI .04–.65, P = .03). This study found that over-the-ball tackling ability was significantly associated with under-the-ball tackling in semiprofessional rugby league players. Furthermore, it was found that, compared with the second-grade players, the first-grade players had superior tackle ability in both tackle drills. In this study it was observed that plyometric push-up peak power was significantly related to over-the-ball tackling ability and absolute lower-body strength was associated with under-the-ball tackling ability. These findings provide skill coaches and strength and conditioning staff a greater understanding of elements that contribute to effective tackling ability.
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Oorschot S, Chiwaridzo M, Cm Smits-Engelsman B. Psychometric evaluation of commonly used game-specific skills tests in rugby: A systematic review. BMJ Open Sport Exerc Med 2017; 3:e000281. [PMID: 29259812 PMCID: PMC5728269 DOI: 10.1136/bmjsem-2017-000281] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2017] [Indexed: 11/04/2022] Open
Abstract
Objectives To (1) give an overview of commonly used game-specific skills tests in rugby and (2) evaluate available psychometric information of these tests. Methods The databases PubMed, MEDLINE CINAHL and Africa Wide information were systematically searched for articles published between January 1995 and March 2017. First, commonly used game-specific skills tests were identified. Second, the available psychometrics of these tests were evaluated and the methodological quality of the studies assessed using the Consensus-based Standards for the selection of health Measurement Instruments checklist. Studies included in the first step had to report detailed information on the construct and testing procedure of at least one game-specific skill, and studies included in the second step had additionally to report at least one psychometric property evaluating reliability, validity or responsiveness. Results 287 articles were identified in the first step, of which 30 articles met the inclusion criteria and 64 articles were identified in the second step of which 10 articles were included. Reactive agility, tackling and simulated rugby games were the most commonly used tests. All 10 studies reporting psychometrics reported reliability outcomes, revealing mainly strong evidence. However, all studies scored poor or fair on methodological quality. Four studies reported validity outcomes in which mainly moderate evidence was indicated, but all articles had fair methodological quality. Conclusion Game-specific skills tests indicated mainly high reliability and validity evidence, but the studies lacked methodological quality. Reactive agility seems to be a promising domain, but the specific tests need further development. Future high methodological quality studies are required in order to develop valid and reliable test batteries for rugby talent identification. Trial registration number PROSPERO CRD42015029747.
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Affiliation(s)
- Sander Oorschot
- Faculty of Health, Medicine and Life Sciences, Department of Human Movement Sciences, Maastricht University, Maastricht, the Netherlands
| | - Matthew Chiwaridzo
- College of Health Sciences, Rehabilitation Department, University of Zimbabwe, Harare, Zimbabwe.,Faculty of Health Sciences, School of Health and Rehabilitation Sciences, Division of Physiotherapy, University of Cape Town, Cape Town, South Africa
| | - Bouwien Cm Smits-Engelsman
- Faculty of Health Sciences, School of Health and Rehabilitation Sciences, Division of Physiotherapy, University of Cape Town, Cape Town, South Africa
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Loturco I. Authors' response to letter to the editor: "Bar velocities capable of optimising the muscle power in strength-power exercises" by Loturco, Pereira, Abad, Tabares, Moraes, Kobal, Kitamura & Nakamura (2017). J Sports Sci 2017; 36:1602-1606. [PMID: 29157139 DOI: 10.1080/02640414.2017.1405712] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Our study in the Journal of Sports Sciences was originally designed to test whether the bar-velocity is a precise indicator of the power training intensity (i.e., optimum loads) in different exercises commonly included in athletes' training programs. Furthermore, we presented secondary findings, related to the actual results obtained in our assessments. As a cross-sectional study with clear objectives, we focused on discussing issues and applications pertaining to neuromuscular training interventions, such as: (1) describing the advantages of using bar-velocities to control the power training intensity, (2) defining a range of loads capable of maximizing the power production in certain ballistic and traditional exercises, and (3) revealing the differences between these exercises and the respective implications for training. Fundamentally, we did not produce a mechanistic investigation and were very accurate and consistent in reporting our data, collected under rigorous and well-established experimental conditions. Here we provide our point-by-point comments to the concerns raised in the "Letter to the Editor", along with some theoretical explanations about the secondary findings reported by the authors of the Letter. To better understand the nature and purposes of our experiment, we also present a series of practical examples and review previous investigations involving the "bar-power" approach.
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Affiliation(s)
- Irineu Loturco
- a NAR - Nucleus of High Performance in Sport , São Paulo , Brazil
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30
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Speranza MJ, Gabbett TJ, Greene DA, Johnston RD, Townshend AD. Tackle characteristics and outcomes in match-play rugby league: the relationship with tackle ability and physical qualities. SCI MED FOOTBALL 2017. [DOI: 10.1080/24733938.2017.1361041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - Tim J. Gabbett
- Gabbett Performance Solutions, Brisbane, Australia
- Institute for Resilient Regions, University of Southern Queensland, Ipswich, Australia
| | - David A. Greene
- School of Exercise Science, Australian Catholic University, Strathfield, Australia
| | - Rich D. Johnston
- School of Exercise Science, Australian Catholic University, Brisbane, Australia
| | - Andrew D. Townshend
- School of Exercise Science, Australian Catholic University, Brisbane, Australia
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31
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Baker DG. Comparison of Strength Levels Between Players From Within the Same Club Who Were Selected vs. Not Selected to Play in the Grand Final of the National Rugby League Competition. J Strength Cond Res 2017; 31:1461-1467. [PMID: 28538293 DOI: 10.1519/jsc.0000000000001604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A number of studies have established that higher levels of strength and power, tested at the end of the preseason, distinguish between playing level in professional rugby league. How this may impact the ability of players to get selected for final payoff games some 30 weeks later has not been fully investigated. The purpose of this study was to compare measures of upper- and lower-body strength between players from the same professional club, designated as those 17 players who attained selection and played in the team that won the Grand Final of the National Rugby League competition (GF) and those who did not attain selection (NSGF). Players were tested and compared for 1 repetition maximum bench press and full squat strength levels at the end of the preparation period, 30 weeks before the GF, using traditional significance analysis of variance and effect size (ES) statistics. Furthermore, the players were analyzed according to the 2 broad positional playing groups of forwards (FWD) and backs (BL). The results demonstrated that overall, the GF players were stronger than NSGF players by approximately 10 and 15%, respectively, for the upper and lower body. When analyzed according to positional groupings, there were significant differences and large ES for GF forwards, who were significantly stronger, heavier, and older than NSGF FWD players. For the BL groups, the differences between the groups were not significant. Because of the intense physical collisions inherent in rugby league, it would appear that higher levels of strength afford players greater performance benefits, resiliency against injury, and greater likelihood of being selected in the most important games at the end of the season.
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Affiliation(s)
- Daniel G Baker
- School of Exercise and Health Sciences, Edith Cowan University, Joondalup, Australia
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Burger N, Lambert MI, Viljoen W, Brown JC, Readhead C, den Hollander S, Hendricks S. Mechanisms and Factors Associated With Tackle-Related Injuries in South African Youth Rugby Union Players. Am J Sports Med 2017; 45:278-285. [PMID: 28125898 DOI: 10.1177/0363546516677548] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The majority of injuries in rugby union occur during tackle events. The mechanisms and causes of these injuries are well established in senior rugby union. PURPOSE To use information from an injury database and assess video footage of tackle-related injuries in youth rugby union matches to identify environmental factors and mechanisms that are potentially confounding to these injuries. STUDY DESIGN Descriptive epidemiological study. METHODS Injury surveillance was conducted at the under-18 Craven Week rugby tournament. Tackle-related injury information was used to identify injury events in match video footage (role-matched noninjury tackle events were identified for the cohort of injured players). Events were coded using match situational variables (precontact, contact, and postcontact). Relative risk ratio (RRR; ratio of probability of an injury or noninjury outcome occurring when a characteristic was observed) was reported by use of logistic regression. RESULTS In comparison with the first quarter, injury risk was greater in the third (RRR = 9.75 [95% CI, 1.71-55.64]; P = .010) and fourth quarters (RRR = 6.97 [95% CI, 1.09-44.57]; P = .040) for ball carriers and in the fourth quarter (RRR = 9.63 [95% CI, 1.94-47.79]; P = .006) for tacklers. Ball carriers were less likely to be injured when they were aware of impending contact (RRR = 0.14 [95% CI, 0.03-0.66]; P = .012) or when they executed a moderate fend (hand-off) (RRR = 0.22 [95% CI, 0.06-0.84]; P = .026). Tacklers were less likely to be injured when performing shoulder tackles (same side as leading leg) in comparison to an arm-only tackle (RRR = 0.02 [95% CI, 0.001-0.79]; P = .037). Ball carriers (RRR = 0.09 [95% CI, 0.01-0.89]; P = .040) and tacklers (RRR = 0.02 [95% CI, 0.001-0.32]; P =.006) were less likely to be injured when initial contact was made with the tackler's shoulder/arm instead of his head/neck. CONCLUSION The relative risk of tackle-related injury was higher toward the end of matches. Incorrect technique may contribute to increased injury risk. Implementing recovery strategies between matches, training safe and effective techniques, and improving levels of conditioning may counter the negative effects of fatigue. These findings may assist stakeholders in youth rugby to formulate injury prevention strategies and may improve the preparation of field-side medical staff for managing tackle-related injuries at these or similar tournaments.
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Affiliation(s)
- Nicholas Burger
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Mike Ian Lambert
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Department of Public & Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands
| | - Wayne Viljoen
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,South African Rugby Union (SA Rugby), Cape Town, South Africa
| | - James Craig Brown
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Department of Public & Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands
| | - Clint Readhead
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,South African Rugby Union (SA Rugby), Cape Town, South Africa
| | - Steve den Hollander
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Sharief Hendricks
- Division of Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Institute for Sport, Physical Activity and Leisure, Centre for Sport Performance, School of Sport, Fairfax Hall, Headingley Campus, Leeds Beckett University, Leeds, UK
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Influence of Fatigue on Tackling Ability in Rugby League Players: Role of Muscular Strength, Endurance, and Aerobic Qualities. PLoS One 2016; 11:e0163161. [PMID: 27798634 PMCID: PMC5087954 DOI: 10.1371/journal.pone.0163161] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 09/02/2016] [Indexed: 12/04/2022] Open
Abstract
This study investigated the influence of repeated high-intensity effort exercise on tackling ability in rugby league players, and determined the relationship between physical qualities and tackling ability under fatigued conditions in these athletes. Eleven semi-professional rugby league players underwent measurements of speed (10 m and 40 m sprint), upper-body strength (4 repetition maximum [RM] bench press and weighted chin-up), upper-body muscular endurance (body mass maximum repetition chin-up, body mass maximum repetition dips), lower-body strength (4RM squat), and estimated maximal aerobic power (multi-stage fitness test). Tackling ability was assessed using a standardized one-on-one tackling test, before, during, and following four bouts of repeated high-intensity effort (RHIE) exercise. The relationship between physical qualities and fatigue-induced decrements in tackling ability were determined using Pearson product moment correlation coefficients. Each cycle of the RHIE protocol induced progressive reductions in tackling ability. A moderate reduction (Effect Size = ~-1.17 ± 0.60, -34.1 ± 24.3%) in tackling ability occurred after the fourth cycle of the RHIE protocol. Players with greater relative lower-body strength (i.e. 4RM squat/kg) had the best tackling ability under fatigued conditions (r = 0.72, p = 0.013). There were no significant relationships between tackling ability under fatigued conditions and any other physical quality. These findings suggest that lower-body strength protects against fatigue-induced decrements in tackling ability. The development of lower-body strength should be a priority to facilitate the development of robust tackling skills that are maintained under fatigue.
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34
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Speranza MJA, Gabbett TJ, Johnston RD, Sheppard JM. Effect of Strength and Power Training on Tackling Ability in Semiprofessional Rugby League Players. J Strength Cond Res 2016; 30:336-43. [PMID: 26813629 DOI: 10.1519/jsc.0000000000001058] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study examined the influence of a strength and power program on tackling ability in rugby league players. Twenty-four semiprofessional rugby league players (mean ± SD age, 23.4 ± 3.1 years) underwent tests of upper-body strength (3 repetition maximum [RM] bench press), lower-body strength (3RM squat), upper-body power (plyometric push-up), and lower-body power (countermovement jump [CMJ]). Muscular strength relative to body mass was also calculated. Tackling ability of the players was assessed using video analysis of a standardized one-on-one tackling drill. The players then underwent 8 weeks of strength and power training as part of their preseason training before being retested. Training resulted in significant (p ≤ 0.01) improvements in absolute and relative measures of squat, bench press, CMJ peak power, and plyometric push-up peak power. The strongest correlates of change in tackling ability were changes in 3RM squat (r = 0.60; p < 0.01) and squat relative to body mass (r = 0.54; p < 0.01). The players with the greatest improvements in 3RM squat and squat relative to body mass (i.e., responders) had significantly greater improvements in tackling ability than nonresponding players (p = 0.04; effect size [ES] ≥ 0.85). A small, nonsignificant difference (p = 0.20; ES = 0.56) in tackling ability was found between responders and nonresponders for lower-body power. The findings of this study demonstrate that the enhancement of lower-body muscular strength, and to a lesser extent muscular power, contribute to improvements in tackling ability in semiprofessional rugby league players.
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Affiliation(s)
- Michael J A Speranza
- 1School of Exercise Science, Australian Catholic University, Brisbane, Australia; 2School of Human Movement Studies, The University of Queensland, Brisbane, Australia; and 3School of Exercise and Health Sciences, Edith Cowan University, Perth, Australia
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35
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Speranza MJA, Gabbett TJ, Greene DA, Johnston RD, Sheppard JM. Changes in Rugby League Tackling Ability During a Competitive Season: The Relationship With Strength and Power Qualities. J Strength Cond Res 2016; 31:3311-3318. [PMID: 27379964 DOI: 10.1519/jsc.0000000000001540] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Speranza, MJA, Gabbett, TJ, Greene, DA, Johnston, RD, and Sheppard, JM. Changes in rugby league tackling ability during a competitive season: the relationship with strength and power qualities. J Strength Cond Res 31(12): 3311-3318, 2017-This study examined the relationship between changes in tackling ability, and muscular strength and power during a semiprofessional rugby league competitive season. Twelve semiprofessional rugby league players (mean ± SD age, 23.3 ± 2.0 years) underwent tests of upper- and lower-body strength and power during the preseason period. Tackling ability was tested using video analysis of a standardized one-on-one tackling drill. Players repeated these tests after round 15 of a 25-match competitive season. Changes in 1 repetition maximum (1RM) squat (rs = 0.70; p < 0.02) and squat relative to body mass (rs = 0.73; p < 0.01) were significantly related to changes in tackling ability. Players with the greatest improvements in tackling ability (i.e., "responders") retained 1RM squat (effect size, ES = 0.85, p = 0.09) and squat relative to body mass (ES = 0.82, p = 0.15) to a greater extent than the "nonresponders." The results of this study suggest that players who retained lower-body strength were able to improve tackling ability during the competitive season, whereas reductions in lower-body strength were associated with decrements in tackling ability. This study highlights the importance of the development and maintenance of lower-body muscular strength for effective tackling performance throughout the rugby league season.
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Affiliation(s)
| | - Tim J Gabbett
- School of Human Movement Studies, The University of Queensland, Brisbane, Australia
| | - David A Greene
- School of Exercise Science, Australian Catholic University, Strathfield, Australia
| | - Rich D Johnston
- School of Exercise Science, Australian Catholic University, Brisbane, Australia
| | - Jeremy M Sheppard
- School of Exercise and Health Sciences, Edith Cowan University, Perth, Australia
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36
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Speranza MJ, Gabbett TJ, Johnston RD, Sheppard JM. Muscular Strength and Power Correlates of Tackling Ability in Semiprofessional Rugby League Players. J Strength Cond Res 2015. [DOI: 10.1519/jsc.0000000000000897] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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37
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Ross A, Gill N, Cronin J, Malcata R. The relationship between physical characteristics and match performance in rugby sevens. Eur J Sport Sci 2015; 15:565-71. [DOI: 10.1080/17461391.2015.1029983] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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38
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Abstract
Rugby league is a team sport in which players engage in repeated high-intensity exercise involving frequent collisions. Recent research, much of which has involved global positioning system (GPS) technology, has provided coaches and sport scientists with a deeper understanding of match demands, particularly at the elite level. This has allowed for the development of training programmes that prepare players for the most intense contact and running demands likely to be experienced in competition. At the elite level, rugby league players have well-developed aerobic and anaerobic endurance, muscular strength and power, reactive agility, and speed. Upper- and lower-body strength and aerobic power are associated with a broad range of technical and sport-specific skills, in addition to a lower risk of injury. Significant muscle damage (as estimated from creatine kinase concentrations) and fatigue occurs as a result of match-play; while muscle function and perceptual fatigue generally return to baseline 48 h following competition, increases in plasma concentrations of creatine kinase can last for up to 5 days post-match. Well-developed physical qualities may minimise post-match fatigue and facilitate recovery. Ultimately, the literature highlights that players require a broad range of physical and technical skills developed through specific training. This review evaluates the demands of the modern game, drawing on research that has used GPS technology. These findings highlight that preparing players based on the average demands of competition is likely to leave them underprepared for the most demanding passages of play. As such, coaches should incorporate drills that replicate the most intense repeated high-intensity demands of competition in order to prepare players for the worst-case scenarios expected during match-play.
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Affiliation(s)
- Rich D Johnston
- School of Exercise Science, Australian Catholic University, 1100 Nudgee Road, Brisbane, QLD, 4014, Australia,
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39
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Morehen JC, Routledge HE, Twist C, Morton JP, Close GL. Position specific differences in the anthropometric characteristics of elite European Super League rugby players. Eur J Sport Sci 2015; 15:523-9. [PMID: 25600232 DOI: 10.1080/17461391.2014.997802] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Rugby league is a collision sport which traditionally adopts a large emphasis on lean muscle mass. Currently there is limited research on the anthropometry of European Super League players. The aim of this study was to assess body composition using Dual Energy X-ray Absorptiometry (DXA) scans to identify the typical profile of elite rugby league players. One hundred and twelve players from five different clubs competing in the European Super League were recruited for the study. DXA scans were performed and the total mass, lean mass, fat mass and percentage body fat were reported for each positional group. For the Fullback and Wingers, Centres, Half Backs, Hookers, Props and Back Row Forwards the mean (SD) body fat percentage was 13 (2.1), 13 (2.4), 12 (3.4), 15 (3.9), 16 (4.3) and 15 (2.1)%, respectively, and total mass was 86 (8.2), 91 (6.6), 81 (8), 84 (9.5) 102 (8.5) and 93 (5.5) kg, respectively. Despite small to very large inter positional differences in all anthropometric variables (effect sizes = -0.08 to 2.56), particularly between the Prop and the other playing positions, there was large intra-position variation in body fat, lean mass and total mass making a standardised position specific profile difficult to establish. When used with other key performance indicators, these data provide the first multi-team anthropometric profile of elite Super League players that can be used to guide individualised training and nutrition practices for current and aspiring athletes.
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Affiliation(s)
- James C Morehen
- a Research Institute for Sport and Exercise Sciences , Liverpool John Moores University , Liverpool , UK
| | - Harry E Routledge
- a Research Institute for Sport and Exercise Sciences , Liverpool John Moores University , Liverpool , UK
| | - Craig Twist
- b Department of Sport and Exercise Sciences , University of Chester , Chester , UK
| | - James P Morton
- a Research Institute for Sport and Exercise Sciences , Liverpool John Moores University , Liverpool , UK
| | - Graeme L Close
- a Research Institute for Sport and Exercise Sciences , Liverpool John Moores University , Liverpool , UK
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40
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Gabbett TJ, Seibold AJ. Relationship between tests of physical qualities, team selection, and physical match performance in semiprofessional rugby league players. J Strength Cond Res 2014; 27:3259-65. [PMID: 23442268 DOI: 10.1519/jsc.0b013e31828d6219] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study investigated the physical qualities that discriminated state-based rugby league players competing for selection in a semiprofessional rugby league team, and determined the relationship between tests of physical qualities and physical match performance in these players. Thirty-two rugby league players (mean ± SD age, 24 ± 3 years) from a Queensland Cup rugby league squad participated in this study. The players performed tests of upper-body strength (3 repetition maximum [RM] bench press; 3RM weighted chin-up), upper-body strength endurance (body-mass maximum repetition bench press), lower-body strength (3RM squat), lower-body power (vertical jump), and prolonged high-intensity intermittent running ability (Yo-Yo intermittent recovery test, level 1). Global positioning system data, sampling at 10 Hz, were collected during 5 Queensland Cup rugby league matches. Selected players had greater (p < 0.05) 3RM squat, 3RM chin-up, body-mass bench press, vertical jump, and Yo-Yo intermittent recovery test performances than nonselected players. After controlling for playing position, players with better 3RM squat performances covered greater total distances (r = 0.98, p < 0.05) including greater distances at low (r = 0.98, p < 0.05) and high (r = 0.97, p < 0.05) speeds. Significant associations (r = 0.96, p < 0.05) were also found between 3RM squat performances and the number of repeated high-intensity effort bouts performed in competition. These findings highlight the importance of lower-body strength, upper-body strength and endurance, and prolonged high-intensity intermittent running ability to team selection in semiprofessional rugby league. Furthermore, our findings suggest that well-developed lower-body strength contributes to effective physical match performance in semiprofessional rugby league players.
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Affiliation(s)
- Tim J Gabbett
- 1School of Exercise Science, Australian Catholic University, Brisbane, Australia; 2School of Human Movement Studies, The University of Queensland, Brisbane, Australia; and 3Melbourne Storm Rugby League Club, Melbourne, Australia
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41
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Johnston RD, Gabbett TJ, Jenkins DG, Hulin BT. Influence of physical qualities on post-match fatigue in rugby league players. J Sci Med Sport 2014; 18:209-13. [PMID: 24594214 DOI: 10.1016/j.jsams.2014.01.009] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/05/2014] [Accepted: 01/23/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVES This study examined the influence of physical qualities on markers of fatigue and muscle damage following rugby league match-play. DESIGN Between subjects design. METHODS Twenty-one male youth rugby league players (age 19.2 ± 0.7 years; height 180.7 ± 5.6 cm; body mass 89.9 ± 10.0 kg) participated in the study. Yo-Yo intermittent recovery test (level 1), 3 repetition maximum back squat and bench press were assessed prior to 2 competitive fixtures. Neuromuscular fatigue (countermovement jump [CMJ] and plyometric push-up [PP]), and blood creatine kinase (CK) were assessed before and after match-play. During match-play, movements were recorded using microtechnology. Players were divided into high- and low-groups based on physical qualities. RESULTS High Yo-Yo and squat performance resulted in greater loads during match-play (p<0.05). There were larger reductions in CMJ power in the low Yo-Yo group at both 24 (ES=-1.83), and 48 h post-match (ES=-1.33). Despite greater internal and external match loads, changes in CMJ power were similar between squat groups. There were larger increases in blood CK in the low Yo-Yo group at 24 (73% vs. 176%; ES=1.50) and 48 h post-match (28% vs. 80%; ES=1.22). Despite greater contact loads, the high squat group exhibited smaller changes in blood CK post-match (ES=0.25-0.39). CONCLUSIONS Post-match fatigue is lower in players with well-developed high-intensity running ability, and lower body strength, despite these players having greater internal and external match loads.
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Affiliation(s)
- Rich D Johnston
- School of Exercise Science, Australian Catholic University, Australia.
| | - Tim J Gabbett
- School of Exercise Science, Australian Catholic University, Australia; School of Human Movement Studies, University of Queensland, Australia
| | - David G Jenkins
- School of Human Movement Studies, University of Queensland, Australia
| | - Billy T Hulin
- School of Exercise Science, Australian Catholic University, Australia
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42
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Gastin PB, McLean OC, Breed RVP, Spittle M. Tackle and impact detection in elite Australian football using wearable microsensor technology. J Sports Sci 2014; 32:947-53. [PMID: 24499311 DOI: 10.1080/02640414.2013.868920] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The effectiveness of a wearable microsensor device (MinimaxX(TM) S4, Catapult Innovations, Melbourne, VIC, Australia) to automatically detect tackles and impact events in elite Australian football (AF) was assessed during four matches. Video observation was used as the criterion measure. A total of 352 tackles were observed, with 78% correctly detected as tackles by the manufacturer's software. Tackles against (i.e. tackled by an opponent) were more accurately detected than tackles made (90% v 66%). Of the 77 tackles that were not detected at all, the majority (74%) were categorised as low-intensity. In contrast, a total of 1510 "tackle" events were detected, with only 18% of these verified as tackles. A further 57% were from contested ball situations involving player contact. The remaining 25% were in general play where no contact was evident; these were significantly lower in peak Player Load™ than those involving player contact (P < 0.01). The tackle detection algorithm, developed primarily for rugby, was not suitable for tackle detection in AF. The underlying sensor data may have the potential to detect a range of events within contact sports such as AF, yet to do so is a complex task and requires sophisticated sport and event-specific algorithms.
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Affiliation(s)
- Paul B Gastin
- a Centre for Exercise and Sports Science, School of Exercise and Nutrition Sciences , Deakin University , Burwood , Australia
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Lorenz DS, Reiman MP, Lehecka BJ, Naylor A. What performance characteristics determine elite versus nonelite athletes in the same sport? Sports Health 2014; 5:542-7. [PMID: 24427430 PMCID: PMC3806174 DOI: 10.1177/1941738113479763] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Context: There are significant data comparing elite and nonelite athletes in anaerobic field and court sports as well as endurance sports. This review delineates specific performance characteristics in the elite athlete and may help guide rehabilitation. Evidence Acquisition: A Medline search from April 1982 to April 2012 was undertaken for articles written in English. Additional references were accrued from reference lists of research articles. Results: In the anaerobic athlete, maximal power production was consistently correlated to elite performance. Elite performance in the endurance athlete is more ambiguous, however, and appears to be related to the dependent variable investigated in each individual study. Conclusion: In anaerobic field and court sport athletes, maximal power output is most predictive of elite performance. In the endurance athlete, however, it is not as clear. Elite endurance athletes consistently test higher than nonelite athletes in running economy, anaerobic threshold, and VO2max.
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Affiliation(s)
- Daniel S Lorenz
- Specialists in Sports and Orthopedic Rehabilitation, Overland Park, Kansas
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45
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Delahunt E, Byrne RB, Doolin RK, McInerney RG, Ruddock CT, Green BS. Anthropometric Profile and Body Composition of Irish Adolescent Rugby Union Players Aged 16–18. J Strength Cond Res 2013; 27:3252-8. [DOI: 10.1519/jsc.0b013e3182915ea6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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46
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Ross A, Gill N, Cronin J. Match Analysis and Player Characteristics in Rugby Sevens. Sports Med 2013; 44:357-67. [DOI: 10.1007/s40279-013-0123-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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47
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Quantification of tackling demands in professional Australian football using integrated wearable athlete tracking technology. J Sci Med Sport 2013; 16:589-93. [DOI: 10.1016/j.jsams.2013.01.007] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 12/04/2012] [Accepted: 01/18/2013] [Indexed: 11/20/2022]
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48
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Castagna C, Ganzetti M, Ditroilo M, Giovannelli M, Rocchetti A, Manzi V. Concurrent Validity of Vertical Jump Performance Assessment Systems. J Strength Cond Res 2013; 27:761-8. [DOI: 10.1519/jsc.0b013e31825dbcc5] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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49
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Wong DP, Chan GS, Smith AW. Repeated-sprint and change-of-direction abilities in physically active individuals and soccer players: training and testing implications. J Strength Cond Res 2013; 26:2324-30. [PMID: 22067248 DOI: 10.1519/jsc.0b013e31823daeab] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The relationship between repeated-sprint ability (RSA) and repeated change-of-direction (RCOD) matched on intervals and distances was investigated in this study. The discrimination abilities of the tests were also examined. Using a within-subject repeated measures design, 25 physically active individuals (ACTs), 16 college soccer players (COL), and 18 professional soccer players (PRO) performed the RSA and RCOD tests during which the fastest time (FT), average time (AT), total time (TT), and percentage decrement score (%Dec) were recorded. We concluded that RSA and RCOD tested separate motor abilities because the shared variance between them in the FT, AT, and TT was ≤50%. Both RSA and RCOD tests were reliable (intraclass correlation coefficient ranged 0.79-0.90) and valid performance assessments in terms of construct in that they discriminated between ACT and soccer players (irrespective of the soccer skill level in this study). Specifically, the FT, AT, and TT (but not %Dec) of RSA and RCOD were significantly higher in ACT as compared with that in both COL and PRO (p < 0.05). Most values of the RSA/RCOD index in COL and PRO were 0.59, which were significantly higher than those of ACT (0.53, p < 0.05). We proposed the use of the RSA/RCOD index with a target value of 0.59 to prioritize and quantify the training needs of RSA and RCOD for soccer players.
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Affiliation(s)
- Del P Wong
- Department of Health and Physical Education, The Hong Kong Institute of Education, Tai Po, Hong Kong.
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50
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Strength Training for Athletes: Does It Really Help Sports Performance? Int J Sports Physiol Perform 2012; 7:2-5. [DOI: 10.1123/ijspp.7.1.2] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The use of strength training designed to increase underlying strength and power qualities in elite athletes in an attempt to improve athletic performance is commonplace. Although the extent to which strength and power are important to sports performance may vary depending on the activity, the associations between these qualities and performance have been well documented in the literature. The purpose of this review is to provide a brief overview of strength training research to determine if it really helps improve athletic performance. While there is a need for more research with elite athletes to investigate the relationship between strength training and athletic performance, there is sufficient evidence for strength training programs to continue to be an integral part of athletic preparation in team sports.
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