Category: Strength and Conditioning
Rugby Science Update 21
By Lara Paul
The aim of this study was to evaluate the implementation of the novel Irish Rugby Football Union Coach Education Framework (CEF) on coach–athlete interactions and perceptions. Specifically, this study aimed to evaluate the impact of coaches’ behaviours during training sessions, the structure of these training sessions within the allocated time the coaches are provided, and the perceptions of both coaches and athletes regarding their relationship and the coaches’ behaviours. Four coaches and 54 players from rugby union youth teams in Ireland participated in this study. Data were collected three times across an 18 month time period: before the CEF intervention; immediately after intervention and at the end of the season post-intervention. Three separate training session observations were recorded for each participating coach with a lapel microphone and a camcorder. The Coach Analysis and Intervention System (CAIS) tool was used to analyse each coach’s behaviour and training session time. Additionally, coaches filled out the Coach-Athlete Relationship Questionnaire (CART-Q) and the players completed the Coaching Behaviour Scale for Sport (CBS-S) Questionnaire. For the intervention, the CEF content was delivered using a facilitated workshop approach focusing on the interpersonal nature of the coaching process. There were significant changes in the coaches’ behaviours after the CEF intervention, including increases in management type behaviour profiles, negative feedback and silence behaviours. Interestingly, there was an increase in negative feedback as opposed to positive feedback, which is not the type of feedback encouraged. Coaches made efforts to increase the volume of their feedback by correcting players’ behaviours but did not use positive feedback that players value. It was also found that coaches did not significantly change their use of time for the training session content. There was mutual satisfaction between the players and their coaches. Coach education needs consistent application over a long time to be successful, but this study shows that the implementation of CEF has encouraging results.
This study is published in the International Journal of Sport Science and Coaching.
The study aims to: 1) assess alternative GPS speed threshold in comparison to a set of male-derived thresholds, 2) identify the effect of these thresholds on high intensity movement distances, and 3) make appropriate recommendations on how to use GPS speed thresholds in women’s rugby union. Fifty-eight Women’s Premier rugby union players took part in this study. Forty-seven of these players performed two 20 meter maximal sprints using the Rugby Football Union testing guidelines for Premier XVs teams to determine maximal velocity. All match GPS data was captured using Catapult Minimax S4 devices. To identify the effect of female‐specific speed thresholds on the match characteristics of players, three sets of thresholds were applied to each data file: one using male-derived criteria and then two alternative thresholds for comparison. When calculating the total high-intensity movement distances in women’s rugby union using the male derived threshold, it equates to 2.1% of the total distance completed in games. Forty-one percent of the players were able to achieve speeds higher than the male derived sprint threshold (21 km.h-1). Significant small to moderate increases were found in total sprint distances when the speed thresholds were adjusted. In total high intensity running distances, significant moderate to large increases were found when the speed thresholds were adjusted. The authors recommend reducing speed thresholds for female rugby union players to the suggested thresholds in this paper (for example: >14 km.h−1 for high‐intensity running and ≥17 km.h−1 for sprinting). This will allow for the production of data that accurately represents the demands experienced in the women’s game, enabling appropriate player preparation.
This study is published in European Journal of Sport Science – Open.
Real‑World Fatigue Testing in Professional Rugby Union: A Systematic Review and Meta‑analysis
The aims of this study were threefold; 1) to perform a systematic review of the literature on the measures used to assess fatigue of professional rugby union players, 2) to complete a meta-analysis of the changes in the neuromuscular, biochemical, self-reported, and heart rate-derived measures associated with monitoring fatigue in professional rugby players, and 3) to provide recommendations based on the literature for monitoring rugby union player fatigue after match play and training in a practical setting. The search was conducted on six electronic databases up to July 2023 (PubMed, SPORTDiscus, Web of Science, Cochrane Library, EMBASE, and MEDLINE). Studies were included if they investigated male rugby union players and focused the influence of match play and/or training on these players, using neuromuscular, biochemical, subjective self-report, and heart rate-derived measures to assess fatigue. A total of 37 full-text articles were included in this review, and 17 full-text articles were included in the meta-analysis. The review was split into four sections: (1) neuromuscular; (2) subjective self-reports; (3) biochemical; and (4) heart rate derived measures. The use of subjective soreness measures to assess fatigue was found to be the most applicable measure in this review. The effectiveness of using countermovement jump height, biochemical markers, and heart rate-derived measures to assess fatigue remains unclear. Although countermovement jump height shows high individual variability, the authors support its use as a fatigue assessment tool in professional rugby union settings, provided it is interpreted on an individual basis.
This study is published in Sports Medicine.
Rugby Science Update 20
By Lara Paul
The state of play for contact training and coaching in women’s rugby
The purpose of this study was to review the current literature on tackle training in contact rugby codes and highlight key messages for coaches and stakeholders as part of a transdisciplinary approach to improve science, safety and gender equity in women’s rugby. The review looked at female specific injury surveillance, prevention, coaches in women’s rugby and match demands. The current literature is sparse but acknowledges the gendered sociocultural and environmental conditions that have influenced women’s experiences of rugby contact and coaching. One cannot copy and paste what has been done from male literature and expect it to work for women’s rugby. Women’s rugby should be understood and coached in a context‐specific manner, considering the needs of the players, coaches and the training environment. Developing and encouraging coaches to execute safe and effective tackle technical actions has been highlighted a priority in women’s rugby. Researchers in all disciplines have been encouraged to work across all levels of women’s rugby, with coaches and athletes, to understand the whole system of women’s rugby. This allows for a holistic approach to developing women’s rugby further. This review also suggests that adapting and adopting progressive tackle skill training frameworks and gender‐responsive coaching practices can aid tackle skill learning.
This study is published in the European Journal of Sport Science – Open Access.
The aims of this study were two-fold: 1) to describe the Head Acceleration Events (HAEs) experienced by professional men’s rugby union players during contact events using statistical modelling techniques appropriate for instrumental mouthguard (iMG) data, and 2) to explore the differences between contact-event types and positional groups. This observational study was conducted during the 2023 Currie Cup and Super Rugby season. Custom Prevent Biometrics iMGs were provided to all players. Post-match data was downloaded from the iMGs to provide linear and angular kinematics. Video analysis data, provided by Opta, included ruck, ball carrier and tackle data. Accelerometer, gyroscope, and proximity sensor data were synchronized to video timestamps of contact events using Matlab. Each HAE was linked to a contact event if their timestamps occurred within 10 seconds of one another. The results from this study show that as the HAEmax magnitude increased, the probability of occurrence decreased. This results in a relatively small probability of higher HAEmax magnitudes in professional male rugby union players. Tackles and ball carries had a greater probability of HAEmax in higher magnitude ranges than rucks. However, the defensive ruck probability profile was closer to tackle and carry events than attacking rucks. The authors suggest that defensive rucks may warrant greater consideration within the injury prevention interventions. No clear differences were found between positions for any of the contact events. The occurrence of HAEmax was associated with roles players performed within contact events, not their actual playing position. These results of HAEmax occurrence can be used to guide and evaluate future HAE reduction strategies in professional rugby union players. Additionally, these results can guide practitioners in planning and player monitoring.
This study is published in Scandinavian Journal of Medicine & Science in Sports.
The purpose of this study to quantify changes in body composition, blood markers, energy requirements, strength, and aerobic capacity of women’s international rugby league players during the lead up to the 2022 Rugby League World Cup (RLWC). Twenty-four international women’s rugby league players participated in this study. Players were tested at three testing points: 1) December 2021, at the beginning of the 2022 Women’s Super League pre-season; 2) March 2022, at the end of the 2022 Women’s Super League pre-season; and 3) October 2022, following the completion of the 2022 Women’s Super League season and prior to the RLWC. Data collection included anthropometric measurements (height and body mass), body composition, resting metabolic rate (RMR), blood profiling, assessments of endurance capacity (VO2max) and isometric strength. This study observed increases in lean mass during the pre-season which aligned with the team’s training goals. Backs demonstrated improvements in VO2max across the three testing points. Interestingly, no significant changes were observed in fat mass, RMR, blood markers, or strength over time. Forwards has a greater body mass and body fat percentages compared to backs. The authors recommend the inclusion of iron profile monitoring in practical settings, especially during intensified training phases, as it can contribute to players’ overall health and performance. Although the iron profiles remained at similar levels across all testing points, it was below the recommended threshold.
This study is published in PLoS ONE.
Rugby Science Update 19
By Lara Paul
Assessing the feasibility of a neck‐strength training intervention in university women’s rugby
The purpose of this study was to pilot a neck strengthening intervention with a university women’s rugby team. Furthermore, the study aimed to understand participant’s perceptions of the training intervention. Fourteen British University rugby union players participated in the study. A fixed‐frame dynamometer was used to assess the multi‐directional isometric neck strength in the participants. They then followed a neck-strengthening program after baseline testing. After completing the programme, they underwent end‐of‐season testing again. The neck strengthening exercises were incorporated into bi‐weekly strength and conditioning sessions and were performed at the end of the session as a team. Following the intervention, semi-structured interviews were conducted to understand the players’ experiences of the testing sessions and intervention and to provide a space for feedback on the intervention. Ten players and two coaches participated in these interviews. Neck strengthening values increased by 9.2%–26.7%, depending on direction. Both players and coaches preferred completing the neck strengthening exercises at the start to the session and in a group. Improvement in educating players and coaches about neck strengthening exercises in needed. The study found that players reported a lack of awareness of neck strength training, and coaches believed that it can only assist in scrum performance. This was a pilot study and further research is required to draw conclusive results.
This study is published in the European Journal of Sport Science – Open Access.
Injury in Starting and Replacement Players from Five Professional Men’s Rugby Unions
The aims of this study were two-fold, 1) to determine if there was an association between the number of replacements and replacement minutes used by one team in a match and the number of injuries to the opposing team, and 2) to determine whether the incidence, severity, and mean of injuries were different between starting and replacement players in professional men’s rugby. Injury and exposure data were collected from men’s professional rugby teams in England, New Zealand, Australia, and South Africa for three seasons. Any replacement player with an exposure of 1 minute or longer was included as a replacement in the analysis. The study found that the use of replacements by one team did not impact the injuries sustained by the opposing team. Overall, injury incidence was similar in starting and replacement players. However, starting players had a higher injury incidence rate than replacement players in the third and fourth match quarters. This finding was attributable to the high injury rates in the starting forwards. Fatigue may be contributing to these injuries. The injury severity and burden were greater in replacements compared with starters. This study allows governing bodies to make evidence-based decisions regarding replacements and does not support any law changes about replacement in the game based on injury risk.
This study is published in Sports Medicine.
Changing gears: data-driven velocity zones to support monitoring and research in men’s rugby league
The aim of this study is twofold: 1) to apply a data-mining approach to league-wide data to identify absolute velocity zone thresholds for male rugby league players, and (2) to apply the respective velocity zones to league-wide data to examine the locomotor demands of individual playing positions within elite match-play. All match data were collected from NRL elite male rugby league players across one season. All players wore microtechnology devices. Following data collection, 10 Hz microtechnology data and match-play time-coded event statistics were analysed. After applying spectral clustering to the league-wide microtechnology dataset, the authors determined four absolute velocity zones ranging from <13.99 km·h−1 to >24.50 km·h−1. The four zones include low: 0–13.99 km·h−1; moderate: 14.00–20.99 km·h−1; high: 21.00– 24.49 km·h−1 and very-high: >24.50 km·h−1. Furthermore, they identified a high speed threshold of >21.00 km·h−1 which is 3.00 km·h−1 higher than the commonly used threshold of >18.00 km·h−1. These results will assist in preparing players for the demands of the game.
This study is published in Science and Medicine in Football.
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