Category: Concussion
Rugby Science Update 13
The objective of this study was to describe the Head acceleration events (HAE) burden across various age groups, ranging from U13 to Senior Premier Club level, and the different playing positions during both matches and training. Data were gathered using Prevent Biometric instrumented mouthguards (iMG) throughout the 2023 community rugby season, involving 328 male rugby players in 48 matches and 113 training sessions across U13, U15, U19, and Senior Premier men levels. All iMGs were equipped with an embedding sensor, triaxial accelerometer and gyroscope to detect ‘on-tooth’ time, as well as linear and angular kinematics, respectively. Additionally, all rugby sessions were recorded. Despite similar rugby exposure time across age grades, the percentage of HAE exposure increased with higher age grade, reflecting elevated match intensity as players matured. Notably, 65% of HAEs occurred during matches for the Senior Premier level, with significantly smaller proportions during matches as age decreased. The study revealed a decline in HAE exposure during training with age. Furthermore, the relative risk of experiencing a high magnitude HAE was found to be is 1.36 times higher for U19 players compared to other levels. When analysing player positions, forwards exhibited a higher HAE exposure rate than backs, particularly in the tackle and ruck events, likely attributed to increased contact for forwards. Interestingly, at the U13 level, backs experienced more low-magnitude HAE during training sessions, presenting an opposite position incidence to Senior Premier players. Tackles accounted for 66–75% of HAE exposure in matches, emphasizing the authors recommendation for the importance of tackle and ruck technique training, particularly for higher grade players.
This study is published in Sports Medicine.
The purpose of this review is to discuss the current knowledge regarding the relationship between body composition (BC) and athletic performance across different ages and sports. Additionally, the review aims to survey the evolution of BC considerations in international sport over the last decade and provide best practice recommendations for BC considerations to prevent potential health and performance consequences. A review search was conducted on PubMed in August 2022 and December 2022, focusing on exploring the impact of athletes’ BC on performance outcomes. The review includes a total of 29 studies, with most of them involving well trained athletes in individual sports. To address the evolution of BC considerations over the last decade, an electronic questionnaire was developed and circulated via social media and email lists. The survey included 125 practitioners from 26 countries working within competitive sports. The findings of this review indicate limited evidence regarding the association between BC and competitive success. Notably, endurance athletes ten to benefit from leanness, and muscle mass is crucial across various sports. Overall, persistent training and experience are essential for talent development and performance success. The survey results highlight the necessity for a more holistic approach to using and reporting BC data over the past decade. Practitioners emphasize the need for awareness and education on how BC assessment affects both performance and health. The survey also highlights that methods have remained largely unchanged over the decades, with practitioners still comparing arbitrary sport-specific ideal BC. The authors emphasize the importance of approaching BC assessments and reporting BC data appropriately. They recommend assessing BC only when necessary and providing the necessary support for athletes to avoid potential health risks. To mitigate these risks, pre-screening should be conducted by the medical and performance team. Testing protocol should be chosen wisely, with a recommended frequency not exceeding 4-6 times a year. Additionally, BC assessment for athletes under the age of 18 is not recommended.
This study is published in British Journal of Sports Medicine.
The primary aim of this study was to investigate changes in player and referee behaviour following the implementation of the lowered (armpit) legal tackle height law variation intervention in amateur community rugby. Additionally, the study aimed to assess on-field referee sanctioning decisions for illegal high tackles. Building on a prior study which implemented the lowered (armpit) legal tackle height law intervention in the amateur community rugby, this research examined referee and player behaviour across three periods of the season. The study involved 42 teams participating in the university rugby club’s four-league, inter-residence competition with the inclusion of 16 referees from the South African Referees Academy. All matches were recorded and video footage from the mounted Go Pro on the referees was captured. Evaluation of on-field referee sanctioning was carried out by a professional South African Rugby Union (SARU) international-level referee, which assessed all videos coded as ‘high’ under the new law variation. The findings of the study revealed a positive on-field behaviour change in both players and referees following the new law variation. There was a significantly higher sanctioning rate by the referees in the middle period of the session, potentially contributing to a significant reduction in upright tackles in the last part of the season. Additionally, there was a fair agreement between the independent referee evaluation and the on-field sanctioning when reviewing the high tackles.
This study is published in the Journal of Science and Medicine in Sport.
Rugby Science Update 12
Cardiovascular risk and systemic inflammation in male professional rugby: a cross-sectional study
The aim of this study was to characterize cardiovascular risk factors, including markers of inflammation, in professional rugby players based on their position. Furthermore, the study compared inflammatory markers in rugby players to those in healthy controls and patients with rheumatoid arthritis (RA). All professional rugby players (n=46) were free from injury and illness at the time of data collection. The rugby players were then categorized by position; forwards (n=21) and backs (n=25). All data collections were collected during the pre-season. Markers of inflammation for the healthy controls and RA patients were obtained from a biobank database at Trinity Biomedical Sciences Institute. Most rugby players in this study exhibited at least one cardiovascular risk factor. Forwards had higher values for all body composition variables, C-reactive protein (CRP) and glucose compared to backs. The rugby player cohort overall showed increased levels of systemic inflammation. One-third of the cohort displayed similarity in inflammation levels to patients with chronic inflammatory diseases. The authors note that the sample size is too small to generalize findings. However, there is a risk of hypertension and dyslipidaemia that should be screened for in rugby players.
This study is published in BMJ Open Sport & Exercise Medicine.
The purpose of this study was to describe the incidence of concussion in the male rugby league at Super League, Championship, and Academy levels between 2016 and 2022. All rugby league medical teams must complete and submit a concussion report within 24 hours of a concussion to the Rugby Football League in elite senior and academy levels. All data used in this study was extracted from this dataset spanning the seasons 2016 to 2022. The data was extracted from the top tier Super League (n = 12 teams), second tier Championship (n = 14 teams), and RFL Academy (n = 12 teams). A total of 1403 concussions were reported (Super League = 538; Championship = 358; Academy = 507). The overall concussion incidence was significantly higher for Super League (15.5 (14.2–16.9) per 1000 player-match hours) and Academy (14.3 (13.1-15.6) per 1000 player-match hours) compared to the Championship (10.5 (9.5-11.7) per 1000 player match hours). One possible reason for this difference is the increased availability of resources for identifying concussions. Additionally, there has been an emphasis on concussion caution for youth players. Concussion incidence in Academy players was higher in the 2021 and 2022 seasons, potentially influenced by COVID-19 pandemic, which limited training and playing opportunities for these players. Lastly, no difference was found in concussion incidence between months at all the levels.
This study is published in the Journal of Science and Medicine in Sport.
The purpose of this study is to explore injuries in Canadian high school rugby boys and provide insights for future injury prevention strategies. Data collection took place during the 2018 and 2019 high-school rugby seasons in Calgary, Alberta. Seven schools were recruited for this study and 12 teams were included. Preseason testing was conducted at the start of the season, with weekly visits to the schools during the season to obtain the injury data. The total time loss injury incidence for matches was 48.4 injury per 1000 hours (95% CI: 37.7-62.0) and a concussion injury incidence of 22.0 concussions per 1000 hours (95% CI: 15.9-30.4). For training injury incidence, the overall time-loss injury incidence was 1.9 injuries per 1000 hours (95% CI: 1.2- 2.9) and the training concussion injury incidence was 0.6 injuries per 1000 hours (95% CI: 0.3-1.2). No significant differences were observed between seasons. The head was the most common injury location in both matches and training, with the concussion being the most common injury type. The tackle event accounted for 65% of match injuries, with the ball carrier contributing to 35% of tackle injuries, followed by the tackler (30%). In training, the tackle constituted 58% of injuries, with the tackler having the highest injury proportion (51%) compared to the ball carrier (7%). The most common mechanism for concussions in matches was being tackled (41%), followed by tackling (53%). In training, the predominant concussion mechanism was tackling (45%), followed by being tackled (23%). The authors highlighted the need for implementation of injury and concussion-specific prevention strategies. Due to the significant number of tackle-related injuries, there is a need to focus on tackle specific injury prevention strategies.
This study is published in the Clinical Journal of Sport Medicine.
Rugby Science Update 8
Professional male rugby union players’ perceived psychological recovery and physical regeneration during the off-season
The aim of this study was to explain the phenomenon of psychological recovery and physical regeneration of male professional rugby union players during the off-season. The study used a qualitative approach to gather the beliefs and experiences of players regarding their mental and physical health and well-being across the off-season period and identify the psychological and physical strategies adopted to recover and regenerate in preparation for the upcoming season. The study interviewed 34 male professional players, and found that the off-season is characterised by three phases that players undergo to preserve their mental and physical health and well-being to recover from the previous season and regenerate in preparation for the upcoming season. These include decompression from previous season, cognitive detachment from the rugby environment and preparation for preseason. Successful progression through all three phases appears to be influenced by variables including the work and life demands a player is encountering at the time, contextual factors such as their health status (ie, currently injured or ill), and their level of experience in the sport (eg, previous experiences of the off-season). The authors recommend players should receive sufficient time (5–6 weeks) in the off-season to progress through the phases of recovery and regeneration to prepare for the upcoming season, with consideration for the impact of work and life demands, contextual factors and experience levels. Also, education should be provided to all stakeholders regarding the importance of the off-season period for well-being (recovery and regeneration), together with strategies that can be used to enhance the quality of this process (ie, physically distancing from work environment to support cognitive detachment from rugby, engaging in development activities that nourish holistic identity and personal skill development). Clinicians should also support, where appropriate, player subgroups at risk of threats to well-being and welfare in the off-season period (long term or recently injured and younger professionals).
This is study is published in BMJ Open Sport & Exercise Medicine and is open access.
Tackling sport-related concussion: effectiveness of lowering the maximum legal height of the tackle in amateur male rugby – a cross-sectional analytical study
The aim of this study was to investigate the effect of a tackle law variation that reduces the maximum legal tackle height from the line of the shoulder of the ball barrier, to the line of the armpit, on injury, head injury and sport-related concussion (SRC) incidence in amateur community rugby union. The study used a cross-sectional analytical design over the period 2018 (control) and 2019 (intervention) in a South African collegiate student rugby competition – which included 42 teams. Reducing the legal tackle height from the line of the shoulder to the armpit of the ball carrier in community amateur rugby showed a trend towards reducing injuries, head injuries and SRC, however, these injury trends were not statistically different.
This study is published in Injury Prevention and is open access.
Performance indicators associated with match outcome within the United Rugby Championship
This study had 3 aims i) identify performance indicators associated with match outcomes in the United Rugby Championship (URC), ii) compare efficacy of isolated data and data relative to opposition in predicting match outcome, and iii) investigate whether reduced performance indicator statistical models can reproduce predictive accuracy. The study analysed 27 performance indicators from 96 matches during the 2020-2021 URC season. Five key performances indicators differentiated between winning and losing in the URC – kicks from hand, metres made, clean breaks, turnovers conceded and scrum penalties. Kicking was highlighted as a key driver for match success, with the probability of winning higher for a team kicking more than their opposition. Also, team performance data are much more efficient at predicting match outcomes when expressed relative to the opposition’s performance.
This study is published in the Journal of Science and Medicine in Sport and is open access.
Scott, G. A., Bezodis, N., Waldron, M., Bennett, M., Church, S., Kilduff, L. P., & Brown, M. R. (2023). Performance indicators associated with match outcome within the United Rugby Championship. Journal of Science and Medicine in Sport, 26(1), 63-68.
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