Rugby Science Update 11

I won’t let you down; why 20% of Men’s and Women’s Super League players underreported suspected concussions

The purpose of this study was to determine the rates of concussion underreporting in male and female Super League rugby players and to establish why players may not report suspected concussions. Furthermore, the study aimed to establish basic concussion knowledge and awareness of the long-term implications of concussions. This study undertook a cross sectional design. A survey was distributed to all registered men’s and women’s players from Super League teams by the Rugby Football League during the 2022 preseason. A total of 422 players completed the survey. Of the 422 players, 20% did not report concussion-related symptoms to the medical staff during the 2020 and 2021 seasons. One third of all players reported at least one concussion diagnosed by a doctor over the last two seasons. The most common reason for not reporting concussion-related symptoms were that players ‘didn’t want to be ruled out of a match’ and ‘didn’t want to let down team’. 62% of players reported receiving annual concussion education at their clubs. Knowledge about concussion and its potential long term implications improved from the beginning of the players senior club level careers. More than half of the players expressed concern about the potential long-term implications of concussions. The authors encourage medical and performance staff to be involved in concussion education to remove any negative perceptions surrounding concussion reporting.

This study is published in the Journal of Science and Medicine in Sport.

Tadmor D, Till K, Phillips G, Brown J, Fairbank L, Hendricks S, Johnston RD, Longworth T, Stokes K, Jones B. I won’t let you down; why 20% of Men’s and Women’s Super League players underreported suspected concussions. J Sci Med Sport. 2023 Sep 27:S1440-2440(23)00416-4. DOI: 10.1016/j.jsams.2023.09.015.

Tackling the tackle 1: a descriptive analysis of 14,679 tackles and risk factors for high tackles in a community-level male amateur rugby union competition during a lowered tackle height law variation trial

The aim of this study was two-fold:  to describe the tackle characteristics during a single season, of community-level rugby conducted under the lowered, armpit-level maximum legal tackle height law variation and investigate factors that were associated with ‘high tackles under the new law’, during this season. The tackle analysis was completed throughout the Koshuis rugby competition in Stellenbosch University rugby club’s intra-university competition in 2018 and 2019, comprising of four leagues with 42 teams. The first year of the study used the standard shoulder-level maximum tackle height law and in the second year of the study the maximum legal tackle height was lowered from the ball carrier’s shoulder to the armpit. All matches were video recorded with referees wore Go Pro camera, and injury surveillance was conducted. The tackles were categorised as ‘high tackle under the new law’ or ‘not high’. A total of 108 matches and 14679 tackles were analysed. The results showed that ‘high tackles under the new law’ had significantly greater odds of occurring in the lower leagues. Notably, factors contributing to high tackles under the law variation condition included, lower front-on arm tackler, tacklers in upright positions, and ball carriers dipping into contact, all of which were associated with an increased risk of head injury. In conclusion, these findings support the implementation of a lowered maximum legal tackle height in rugby union. The authors did mention that when lowering the maximum legal tackle height, the ball carrier’s behaviour in the tackle event needs to be considered.

This study is published in the Journal of Science and Medicine in Sport.

R. van Tonder, S. Hendricks, L. Starling, et al., Tackling the tackle 1: a descriptive analysis of 14,679 tackles and risk factors for high tackles in a community-level male amateur rugby union competition during a lowered tackle height law variation trial, Journal of Science and Medicine in Sport (2023), https://doi.org/10.1016/j.jsams.2023.10.011

Coach and player rating of perceived challenge (RPC) as a skill monitoring tool in Rugby Union

The aim of this study was to determine the relationship between player and coach Rating of Perceived Challenge (RPC) for different training sessions over a competitive rugby union season and explore the relationship between player RPC and Rating of Perceived Exertion (RPE). This observational study monitored 51 highly trained U21 rugby union players and four coaches over an 11-week competitive rugby season. Throughout the season players were asked for their RPC and RPE ratings 15 to 30 minutes after each team session, split session, and gym session, while the coaches were asked to provide their RPC ratings based on observation. All ratings were collected independently and confidentially. The key finding in this study was that, overall, players’ RPC did not match the coaches RPC, suggesting that the rugby union coaches may be overestimating the technical and tactical challenge of their training sessions. Additionally, forwards had a higher RPC for field sessions, likely due to their additional technical and tactical demands from training scrums, lineouts, and mauls. The authors mentioned that further robust validity studies are needed.

This study is published in the International Journal of Sports Science and Coaching.

Bam, J., Watson, N., Parker, N., Lambert, M., Jones, B., Weston, M., & Hendricks, S. (2023). Coach and player rating of perceived challenge (RPC) as a skill monitoring tool in Rugby union. International Journal of Sports Science & Coaching, 18(4), 1010-1017. https://doi.org/10.1177/17479541231166287

Rugby Science Update 10

Predicting performance at the group-phase and knockout-phase of the 2015 Rugby World Cup

The objective of this study was to develop a predictive model for performance during the group-phase of the 2015 Rugby World Cup (RWC) and to determine the most significant and relevant performance indicators for predicting match outcome. Performance indicators were downloaded from the OPTA website from the 2015 RWC (40 group-phase and 8 knockout-phase matches) to be analysed. A random forest classification model was developed to establish the relationship between the performance indicators and the match outcomes. The model created using the group-phase matches achieved a 100% accuracy of predicting match outcomes. When applied to the knockout-phase matches, this model had an overall accuracy of 87.5%, with sensitivity and specificity of 87.5%. The model identified 13 performance indicators that significantly predicted match outcomes. These included tackle-ratio, clean breaks, average carry, lineouts won, penalties conceded, missed tackles, lineouts won in the opposition 22, defenders beaten, metres carried, kicks from hand, lineout success, penalties in opposition 22 m and scrums won. The performance indicators in the group-phase matches that could predict the match outcomes were tackle ratio, clean breaks and average carry. Interestingly, the performance indicators do not change from the group to knockout stages. The findings of this study provide insights for rugby teams to assess their performance and understand the major technical factors contributing to success and failure in individual matches. Coaches and sport practitioners can then adjust their technical and tactical training appropriately.

This study is published in European Journal of Sport Science.

Mark Bennett, Neil E. Bezodis, David A. Shearer & Liam P. Kilduff (2021) Predicting performance at the group-phase and knockout-phase of the 2015 Rugby World Cup, European Journal of Sport Science, 21:3, 312-320, DOI: 10.1080/17461391.2020.1743764

Statistical Review and Match Analysis of Rugby World Cups Finals

The purpose of this study was to describe game statistics and match analysis of Rugby World Cups from 1987 to 2015. The analysis focused on all final matches (n = 8) from 1987 to 2015 Rugby World Cups, and official reports from the Rugby World Cup webpages were also included in the analysis.  This analysis included tracking counts of all match activities. 39 key performance indicators were categorised into seven groups: mode of scoring, set-pieces, defensive, offensive, infringements, replacements, and team/time possession efficiency. It was observed that the winning teams of the final matches in the Rugby World Cup attempted more penalty kicks. Interesting, the number of drop goals were similar between the winning and losing teams.  The winning teams won more set pieces, including winning scrums and lineouts. In the defensive category, the winning teams attempted and completed more tackles than the losing teams. Regarding, the offensive category, the winning teams passed less, completed fewer offloads, and were involved in more rucks and mauls. Interestingly, it was noted that the losing teams made more substitutions than the winning teams. Furthermore, both teams in the Rugby World Cup finals shared similar possession of the ball.  The authors of the study mentioned the importance of player emotions, as well as conducting more in-depth match analysis to enhance team performance characteristics.

This study is published in Journal of Human Kinetics.

Vaz, Luís & Hendricks, Sharief & Kraak, Wilbur. (2019). Statistical Review and Match Analysis of Rugby World Cups Finals. Journal of Human Kinetics. 66. DOI: 10.2478/hukin-2018-0061.

How to harness and improve on video analysis for youth rugby player safety: a narrative review

The purpose of this narrative review is to synthesize the strengths and limitations of video analysis in youth rugby used for injury surveillance, highlight the importance of video analysis for youth player safety and discuss recommendations. This review highlights multiple strengths and limitations of video analysis in youth rugby for injury surveillance. It is recommended in this review that video assessment of injury and concussion outcomes be prioritised to educate, inform and improve youth rugby safety. The importance of analysing these outcomes is highlighted within this review which develops and guides targeted injury and concussion prevention strategies. Furthermore, a video analysis framework consensus that is specific to youth rugby is needed.

This study is published in BMJ Open Sport & Exercise Medicine.

Shill IJ, West SW, Brown J, Wilson F, Palmer D, Pike I, Hendricks S, Stokes KA, Hagel BE, Emery CA. How to harness and improve on video analysis for youth rugby player safety: a narrative review. BMJ Open Sport Exerc Med. 2023 Sep 27;9(3):e001645. DOI: 10.1136/bmjsem-2023-001645.

Rugby Science Update 9

More than rugby: A scoping review of coaches in rugby

The purpose of this review was to synthesize the current coach-focused literature on rugby union, rugby league and rugby sevens. Using a scoping review approach, 105 articles were analysed. Ten coaches were also consulted for insight into whether they found the review beneficial for coaches and how researchers can improve the coach–research relationship. 44 of these studies reported male coaches, 3 reported female coaches and 18 reported both male and female coaches. Most of the studies focused on coaches within rugby union (76%) and rugby league (14%). The remainder of the studies focused on a combination of rugby cohorts (4%), and only one study focused on rugby sevens (1%).  Three themes were formed after a thematic analysis which included themes on coach knowledge (n=71), coach pedagogies (n=30) and coach development (n=4). The key finding within this review was that coaches had a good understanding of injury risk, prevention and management, specifically on concussions. The main strategy to improve coaches’ understanding of injury risk, prevention, and management of all aspects of injury is by providing coach educational resources, such as workshops and injury prevention programmes. Also, coaches are encouraged to build knowledge on all aspects related to rugby performance, such as technical and tactical knowledge. Another key finding of this review was the importance of the athlete–coach relationship, as well as coach reflective practice. Additionally, there is a shift in coaching pedagogy, from a coach-centred approach towards a player-centred approach.  This review focused on the three themes of key research areas and found that integrating all themes could improve rugby coaching research and practice moving forward.

This study is published in International Journal of Sports Science & Coaching.

Paul, L., Davidow, D., Stodter, A., Till, K., Dane, K., Jones, B., & Hendricks, S. (2023). More than rugby: A scoping review of coaches in rugby. International Journal of Sports Science & Coaching, 0(0). https://doi.org/10.1177/17479541231185558

Mental Fatigue Impairs Tackling Technique in Amateur Rugby Union Players

The aim of this study was to test the effects of a mentally fatiguing protocol on rugby union players’ tackling technique on both their dominant and non-dominant shoulders. 20 amateur rugby union players from the Western Province Super League A participated in this study. The study used a randomized, crossover, counterbalanced design. Players visited the laboratory twice: once for the non-Mental Fatigue condition (control) and then the Mental Fatigue condition. After a warmup, the players underwent the protocol. The protocol required each player to perform 4 sets of 6 tackles on the tackle simulator located at the University of Cape Town. Three tackles on the dominant shoulder and three tackles on the non-dominant shoulder were completed in random order. A lighting system that is mounted behind the tackle dummy flashed prior to the dummy being released to indicate which shoulder the player should tackle. After the baseline tackle set (the first set of tackles), the players in the Mental Fatigue condition performed a 30-minute Stroop Task, with two 5-minute Stroop top-ups after the next two sets. If players were completing the control condition, the players rested and were allowed to read magazines for the same time frame. At a later stage, each tackle was recorded and scored using a standardized list of technical criteria to determine how technically correct each tackle was. The authors found that mental fatigue can impair a rugby player’s tackle technique, and these impairments are greater when tackling on the non-dominant shoulder. The technical components that were significantly impaired by the mental fatigue protocol was “explosiveness (rapid movement) on contact.”  It is recommended that sport practitioners include a mental fatigue component into tackle training programmes to improve and develop tackle technique and capacity.

This study is published in International Journal of Sports Physiology and Performance.

Davidow, D., Smith, M., Ross, T., Laura James, G., Paul, L., Lambert, M., Jones, B., & Hendricks, S. (2023). Mental Fatigue Impairs Tackling Technique in Amateur Rugby Union Players. International Journal of Sports Physiology and Performance. https://doi.org/10.1123/ijspp.2023-0159

‘Body on the line’: experiences of tackle injury in women’s rugby union – a grounded theory study

The aim of this study was to describe and understand the tackle injury experiences and behaviours in women’s rugby union. This study undertook a qualitative grounded theory approach, which explores how and why women rugby union players behave in different contexts. Twenty-one women rugby union players were interviewed about their tackling injury experience from Canada, South Africa, and Europe. After the data analysis was completed, the findings were split into three categories: (1) embodied understandings of tackle injury; (2) gender and tackle injury risk and (3) influences on tackle injury behaviours. The authors found that within the rugby culture, players normalised pain and injury, which impacts the players physical and emotional health. Female rugby players desired respect and recognition from coaches and teammates to prove their place in rugby. Therefore, players often played through their injuries and ‘put their body on the line’. Furthermore, players would be rewarded for ‘putting their bodies on the line’. Players also reported that tackle experiences were filled with fear, stemming from being underprepared for the tackle. The authors recommended that tackle injury prevention should become a priority at all levels to ensure women have an inclusive and equal playing environment compared to their male counterparts.

This study is published in British Journal of Sports Medicine.

Dane K, Foley G, Wilson F (2023). ‘Body on the line’: experiences of tackle injury in women’s rugby union – a grounded theory study. British Journal of Sports Medicine. doi: 10.1136/bjsports-2022-106243