The effect of physical fatigue on tackling technique in Rugby Union

Tackling the tackle 2: Evaluation of referee and player behavioural change as measures of implementation of a law variation in community-level male amateur rugby union

OBJECTIVES

To evaluate player and referee behaviour during a lower tackle height law variation trial in community rugby union ('rugby').

DESIGN

Prospective observational cohort study.

METHODS

In a law variation trial in male amateur community rugby, coded match video surveillance data were analysed. Referee (sanctioning rate) and player (tackler body position) behaviour changes over one season (under the lowered, armpit-level maximum legal tackle height condition) were analysed in three approximately equal periods of the season. Secondarily, an independent professional referee reviewed illegal high tackle sanctioning data.

RESULTS

Overall, 108 matches with 14,780 tackles were filmed and coded. Sanctioned illegal high tackle propensity was significantly higher in the mid-season (41 sanctioned high tackles/1000 tackle events; 95 % CI: 35-47), compared with first and last periods. Upright tacklers in tackles decreased significantly in the final vs. middle period of the season (rate ratio: 0.69; 95 % CI: 0.54-0.88; p < 0.01). Of all the coder-determined high tackles also assessed as high under the new law by the independent referee, 51 % were sanctioned by the on-field referee.

CONCLUSIONS

Positive player and referee behavioural changes were observed during a lowered legal tackle height law variation in this community rugby setting. Increased mid-phase high tackle sanctioning by referees was followed by fewer tackles with upright tacklers in the subsequent (last) phase of the season. Encouraging positive behaviour changes of this nature, particularly if sustained (beyond trial study periods), may contribute to overall injury risk reduction, and hold considerable importance to inform future injury prevention strategies in rugby.

Acute Effects of Fatigue on Cardiac Autonomic Nervous Activity

The onset of fatigue disrupts the functioning of the autonomic nervous system (ANS), potentially elevating the risk of life-threatening incidents and impairing daily performance. Previous studies mainly focused on physical fatigue (PF) and mental fatigue (MF) effects on the ANS, with limited knowledge concerning the influence of physical-mental fatigue (PMF) on ANS functionality. This study aimed to assess the immediate impact of PMF on ANS function and to compare its effects with those of PF and MF on ANS function. Thirty-six physically active college students (17 females) without burnout performed 60-min cycling exercises, AX-Continuous Performance Task (AX-CPT), and cycling combined with AX-CPT to induce PF, MF, and PMF respectively. Subjective fatigue levels were measured using the Rating of Perceived Exertion scale and the Visual Analog Scale-Fatigue. Heart rate variability was measured before and after each protocol to assess cardiac autonomic function. The proposed tasks successfully induced PF, MF, and PMF, demonstrated by significant changes in subjective fatigue levels. Compared with baseline, PMF decreased the root mean square of successive differences (RMSSD) between normal heartbeats (P < 0.001, d = 0.50), the standard deviation of normal-to-normal RR intervals (SDNN) (P < 0.01, d = 0.33), and the normalized high-frequency (nHF) power (P < 0.001, d = 0.32) while increased the normalized low-frequency (nLF) power (P < 0.001, d = 0.35) and the nLF/nHF ratio (P < 0.001, d = 0.40). Compared with MF, PMF significantly decreased RMSSD (P < 0.001, η2 = 0.431), SDNN (P < 0.001, η2 = 0.327), nLF (P < 0.01, η2 = 0.201), and nHF (P < 0.001, η2 = 0.377) but not the nLF/nHF ratio. There were no significant differences in ΔHRV (i.e., ΔRMSSD, ΔSDNN, ΔnLF/nHF, ΔnLF, and ΔnHF), heart rate, and training impulse between PF- and PMF-inducing protocols. Cognitive performance (i.e., accuracy) in AX-CPT during the PMF-inducing protocol was significantly lower than that during the MF-inducing protocol (P < 0.001, η2 = 0.101). PF and PMF increased sympathetic activity and decreased parasympathetic activity, while MF enhanced parasympathetic activity.

Classifying Winning Performances in International Women's Rugby Union

PURPOSE

The efficacy of isolated and relative performance indicators (PIs) has been compared in rugby union; the latter more effective at discerning match outcomes. However, this methodology has not been applied in women's rugby. The aim of this study was to identify PIs that maximize prediction accuracy of match outcome, from isolated and relative data sets, in women's rugby union.

METHODS

Twenty-six PIs were selected from 110 women's international rugby matches between 2017 and 2022 to form an isolated data set, with relative data sets determined by subtracting corresponding opposition PIs. Random forest classification was completed on both data sets, and feature selection and importance were used to simplify models and interpret key PIs. Models were used in prediction on the 2021 World Cup to evaluate performance on unseen data.

RESULTS

The isolated full model correctly classified 75% of outcomes (CI, 65%-82%), whereas the relative full model correctly classified 78% (CI, 69%-86%). Reduced respective models correctly classified 74% (CI, 65%-82%) and 76% (CI, 67%-84%). Reduced models correctly predicted 100% and 96% of outcomes for isolated and relative test data sets, respectively. No significant difference in accuracy was found between data sets. In the relative reduced model, meters made, clean breaks, missed tackles, lineouts lost, carries, and kicks from hand were significant.

CONCLUSIONS

Increased relative meters made, clean breaks, carries, and kicks from hand and decreased relative missed tackles and lineouts lost were associated with success. This information can be utilized to inform physical and tactical preparation and direct physiological studies in women's rugby.

The relationship between physical characteristics and match collision performance among elite international female rugby union players

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.

Mental Fatigue Impairs Tackling Technique in Amateur Rugby Union Players

PURPOSE

To test the effects of mental fatigue (MF) on tackling technique on the dominant and nondominant shoulders in rugby union.

METHODS

Twenty male amateur rugby union players and a total of 953 tackles were analyzed. A randomized crossover counterbalanced design was used across a non-MF (control) and an MF condition. During each condition, each player performed 24 tackles, divided into 4 sets of 6 tackles (3 tackles on each shoulder). In the MF condition, players performed the Stroop Task between each set of tackles. A video recording of each tackle was used to evaluate each player's technical proficiency. A score of 1 point was awarded if a specific technique was performed correctly, and 0 point was given if not. The total score, measured in arbitrary units (AU) out of 11, represents the player's overall tackling proficiency.

RESULTS

Overall, players displayed a significantly lower technical proficiency score in the MF condition compared to control (set 2: control 7.30 [7.04-7.57] AU vs MF 6.91 [6.70-7.12] AU, P = .009, effect size (ES) = 0.30 small and set 3: control 7.34 [7.11-7.57] AU vs MF 6.88 [6.66-7.11] AU, P = .002, ES = 0.37 small). For the nondominant shoulder, players had a significantly lower technical proficiency score during the MF condition at set 2 (control 7.05 [6.68-7.41] AU vs MF 6.69 [6.42-6.96] AU, P = .047, ES = 0.29 small) and set 3 (control 7.14 [6.83-7.45] AU vs MF 6.61 [6.35-6.87] AU, P = .007, ES = 0.49 small).

CONCLUSIONS

MF can diminish a player's overall tackling proficiency, especially when tackling on the nondominant shoulder. The physiological mechanism for this finding may be impaired executive function and suboptimal functioning of neural signals and pathways, which result in less skillful coordination of movement. To further understand and explain MF-induced physiological changes in tackling, the feasibility of monitoring brain activity (such as electroencephalogram) and neuromuscular function (such as electromyogram) needs to be investigated. The findings from this study may also contribute to the development of more effective tackle training programs for injury prevention and performance.

Video-based technical feedback and instruction improves tackling technique of community rugby union players

The aims of this study were to test the change and retention of player's overall tackling technique and technical components following a player-specific video-based technical feedback and instruction intervention on both their dominant and non-dominant shoulders. Twenty-four (n = 24) rugby union players participated in a non-randomized control-intervention, which consisted of a video-based technical feedback and instruction group (video-based technical feedback) and a no video-based technical feedback and instruction group (control). During 3 sessions (baseline, intervention, retention) separated by one week, participants in each group performed six tackles (3 tackles on each shoulder) on a tackle simulator. In total, 432 tackles (video-based technical feedback = 216, control = 216) were analysed. Each tackle was analysed using a standardized list of technical criteria (arbitrary units, AU). For the dominant shoulder, tackling technique scores significantly improved from baseline to intervention for both groups. For the non-dominant shoulder, only the video-based technical feedback group improved their tackling technique from baseline to intervention (baseline 6.89 [6.33-7.45] AU vs. intervention 7.72 [7.35-8.10] AU p = .001, ES = 0.60 moderate). For the retention session, the video-based technical feedback group scored significantly higher than the control group, for dominant (video-based technical feedback 8.00 [7.60-8.40] AU vs. control 7.22 [6.83-7.62] AU p = .014, ES = 0.66 moderate) and non-dominant (video-based technical feedback 8.11 [7.81-8.41] AU vs. control 7.22 [6.90-7.55] p = .004, ES = 0.96 moderate) tackles. This study demonstrates the efficacy of video-based technical feedback as a method to optimize tackle training for player safety and performance. HIGHLIGHTSVideo-based technical feedback can improve tackling technique in both dominant and non-dominant shoulders.Video-based technical feedback group continued to improve following a retention interval of one week.The video-based technical feedback group showed a significant (with a moderate effect size) improvement from baseline for two techniques - namely, "body position - upright to low" and "drive through contact with legs and shoulders".Video-based technical feedback can be used as a method to optimize tackle training for injury prevention and performance.

Injury Trends for School Rugby Union in Ireland: The Need for Position-specific Injury-prevention Programs

BACKGROUND

Concern has been raised over the injury risk to school Rugby union (Rugby) players and the potential long-term health consequences. Despite the increase in studies for this cohort, the influence of playing position on injury incidence and presentation is unclear.

PURPOSE

To describe the incidence, nature and severity of match injuries for school Rugby in Ireland overall, and as a function of playing position.

STUDY DESIGN

Prospective cohort study.

METHODS

Data were collected from 15 male (aged 16-19 years) school Senior Cup teams across 2 seasons. In total, 339 players participated in season 1, whereas 326 players participated in season 2. Injury data were recorded onto a bespoke online platform. Match exposure was also recorded.

RESULTS

The incidence rate of match injuries (24-hour time loss) was 53.6 per 1000 hours. Across both seasons, 6810 days were lost from play due to injury. Forwards (65.4 per 1000 hours) sustained significantly more (P < 0.05) injuries than backs (40.5 per 1000 hours). The head, shoulder, knee, and ankle were the most common injured body regions; however, forwards sustained significantly more (P < 0.05) head and shoulder injuries than backs. The tackle was responsible for the majority of injuries in both groups. The highest proportion of injuries occurred during the third quarter.

CONCLUSION

Clear differences in injury presentation and incidence were evident when comparing forwards versus backs. The high rate of head and shoulder injuries in the forwards suggest the need for more targeted injury-prevention strategies and further research on education and laws around the tackle event. The spike of injuries in the third quarter suggests that fatigue or inadequate half-time warm-up may be a contributing factor warranting further exploration.

CLINICAL RELEVANCE

This study demonstrates clear differences in injury presentation according to playing position in school Rugby and highlights the need for a more tailored approach to the design and implementation of injury-prevention strategies.

LEVEL OF EVIDENCE

Level 3.

Evaluating the relationship between neurological function, neuromuscular fatigue, and subjective performance measures in professional rugby union players

Managing the health and wellbeing of full-time professional athletes is a multifaceted task. In elite high-performance environments, medical staff and strength training coaches attempt to identify improved methods to monitor player health. Monitoring player health could indicate potential injury risk and assist in adjustments to training and workload management. Measuring fatigue is a notable component of monitoring player readiness before and after training sessions, and after competitive fixtures. In the present study, a novel method of gathering non-invasive player data was investigated by utilizing the Omegawave (OW) to monitor direct current (DC) potential brainwave activity. This method allowed for non-invasive data gathering to assess recovery, player readiness and indicators of workload that may affect optimal performance. DC potential is based on recording low electrical frequencies (&gt;0.5 Hz) that is derived from (1) Stabilization point of DC potential (mV), (2) Stabilization time (1.0–7.0) and (3) Curve shape (1.0–7.0). These measures evaluate the athlete's internal stress, readiness to perform, and neurological function through DC potential brain wave activity and heart rate variability (HRV) assessments. The primary aim of this case series was to compare the efficacy of objective DC potential brainwave activity measurements (neurological function) with neuromuscular fatigue data using reactive strength index modified (RSImod) and profile of mood states (POMS) questionnaires to assess a player's state of readiness to train. The participants in this study were eleven male senior professional rugby union players with a mean stature (±SD) of 185.2 ± 8.6 cm, mass of 101.1 ± 12.9 kg, and age of 27.1 ± 2.1 years. All players were tested 3 days per week over a 6-week mid-season period. Results from this case study suggest that DC potentials could be used as an objective measure to indicate player readiness and managing individual player workload. The final analyses identified a weak negative correlation (r = −0.17) between the RSImod data and the DC potential data was observed. DC potential brainwave activity data could be used in conjunction with subjective measures such as POMS, RSImod and reported injury status to adjust player daily activity.

Tackle Technique and Changes in Playerload™ During a Simulated Tackle: An Exploratory Study

In collision sports, the tackle has the highest injury incidence, and is key to a successful performance. Although the contact load of players has been measured using microtechnology, this has not been related to tackle technique. The aim of this study was to explore how PlayerLoad™ changes between different levels of tackling technique during a simulated tackle. Nineteen rugby union players performed twelve tackles on a tackle contact simulator (n = 228 tackles). Each tackle was recorded with a video-camera and each player wore a Catapult OptimEyeS5. Tackles were analysed using tackler proficiency criteria and split into three categories: Low scoring(≤5 Arbitrary units (AU), medium scoring(6 and 7AU) and high scoring tackles(≥8AU). High scoring tackles recorded a higher PlayerLoad™ at tackle completion. The PlayerLoad™ trace was also less variable in the high scoring tackles. The variability in the PlayerLoad™ trace may be a consequence of players not shortening their steps before contact. This reduced their ability to control their movement during the contact and post-contact phase of the tackle and increased the variability. Using the PlayerLoad™ trace in conjunction with subjective technique assessments offers coaches and practitioners insight into the physical-technical relationship of each tackle to optimise tackle skill training and match preparation.

Injuries in Elite Men's Rugby Union: An Updated (2012-2020) Meta-Analysis of 11,620 Match and Training Injuries

BACKGROUND

The most recent meta-analytic review of injuries in elite senior men's Rugby Union was published in 2013. The demands of the game at the elite level are continually changing alongside law amendments and developments in player preparation. As such, an updated meta-analysis of injury data in this setting is necessary.

OBJECTIVE

To meta-analyse time-loss injury data in elite senior men's Rugby Union between 2012 and 2020.

METHODS

Electronic databases were searched using the keywords 'rugby' and 'inj*'. Nineteen studies met the inclusion criteria. Injury incidence rate data were modelled using a mixed-effects Poisson regression model. Days missed data were modelled using a general linear mixed model.

RESULTS

The included data encompassed a total of 8819 match injuries and 2801 training injuries. The overall incidence rate of injuries in matches was 91 per 1000 h (95% confidence interval (CI) 77-106). The estimated mean days missed per match injury was 27 days (95% CI 23-32). The overall incidence rate of match concussions was 12 per 1000 h (95% CI 9-15). The overall incidence rate of training injuries was 2.8 per 1000 h (95% CI 1.9-4.0). Playing level was not a significant effect modifier for any outcome.

CONCLUSIONS

The injury incidence rate and mean days missed per injury in the present meta-analysis were higher, but statistically equivalent to, the 2013 meta-analysis (81 per 1000 h and 20 days, respectively). The injury incidence rate for match injuries in elite senior men's Rugby Union is high in comparison to most team sports, though the training injury incidence rate compares favourably. The tackle event and concussion injuries should continue to be the focus of future preventative efforts.

Epidemiology of Tibial Fractures in Professional American Football Athletes From 2013 to 2019

Background:

Lower extremity injuries occur with high frequency in National Football League (NFL) athletes and cause high burden to players and teams. Tibial fractures are among the most severe lower extremity injuries sustained in athletes and are associated with prolonged time loss from sport.

Purpose:

To determine the number of tibial fractures in NFL athletes from the 2013 to 2019 NFL seasons and describe athlete demographics, fracture characteristics, and details of injury onset.

Study Design:

Case series; Level of evidence, 4.

Methods:

A retrospective review of the NFL injury database was performed to identify all NFL athletes sustaining tibial fractures over the 2013 to 2019 NFL seasons. Athlete characteristics, injury characteristics, days missed, and treatment (operative vs nonoperative) were examined. Descriptive statistics were used to calculate means, standard deviations, ranges, and percentages.

Results:

A total of 64 tibial fractures were identified in 60 athletes, resulting in a median loss of 74 days. Defensive secondary athletes had the highest number of injuries (n = 10; 16%), followed by running backs (n = 9; 14%), while 61% of these injuries occurred during NFL regular-season games, primarily between weeks 13 and 17. The most commonly reported activity during injury was athletes being tackled, with a direct impact to the tibia being the most common mechanism of injury. Lateral tibial plateau fractures were the most frequently reported, while distal tibial fractures resulted in the greatest number of days lost. The median time lost for injuries requiring surgery was 232 days compared with 56 days for injuries treated using conservative management.

Conclusion:

The highest proportion of tibial fractures were injuries to defensive secondary athletes and athletes being tackled while sustaining a direct impact to the leg, primarily to the lateral tibial plateau. Tibial fracture injuries were commonly sustained during NFL regular-season games, primarily during the final 4 weeks of the NFL regular season. Further investigations examining performance and career longevity in athletes sustaining tibial fractures are warranted to help improve the health and safety of NFL athletes.

Return to play protocols for musculoskeletal upper and lower limb injuries in tackle-collision team sports: A systematic review

Athletes in tackle-collision teams are at high risk of musculoskeletal injuries resulting in absence from play due to the high impact nature of the sport. There is a paucity of research to guide the management and assessment methods needed to facilitate the return to play (RTP) process. This review aimed to describe, synthesise and evaluate RTP protocols implemented for musculoskeletal injuries in tackle-collision teams. A systematic search of Scopus, PubMed, Web of Science and Ebsco Host was conducted for RTP management protocols and assessment modalities following upper and lower limb musculoskeletal injuries in tackle-collision team athletes. Prospective and retrospective quantitative controlled trials, cohort, case-control, case-series and cross-sectional observation studies published between January 2000 and March 2020 were considered. The main outcome measures were the proportion of athletes to RTP, associated time-loss and reinjury risk. 5265 articles were screened. 34 studies met the eligibility criteria of which 23 involved management and 11 assessment modalities. Management involved surgical or conservative strategies along with exercise-based rehabilitation. Assessment modalities included radiographic assessment, clinical evaluation and subjective ratings. Promising RTP management included progressive weight-bearing and exercised-based rehabilitation for ankle sprains as well as surgery, the use of a sling and exercise-based rehabilitation for shoulder instability. MRI scans showed promise in predicting time-loss following hamstring and calf strains in tackle-collision athletes. There are currently no clear guidelines for RTP after musculoskeletal injuries in tackle-collision sports. Future research should investigate efficient management strategies evaluated through valid and reliable assessment methods to better guide clinicians.

Epidemiology of Shoulder Injuries in Schoolboy Rugby Union in Ireland

BACKGROUND

The shoulder has been reported as a frequent location of injury in adult professional and amateur rugby, with match injury incidence rates ranging from 1.8 to 3 per 1000 player-hours (h). An increased understanding of the incidence and mechanism of shoulder injuries in school rugby players is vital to establish effective injury preventive strategies and advise on appropriate rehabilitation.

PURPOSE

To describe the incidence, nature, and severity of shoulder injuries in schoolboy rugby in Ireland.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

Injury surveillance was carried out for Senior Cup teams across two seasons (N = 665 players aged 17-19 years) in Ireland from 2018 to 2020. Match and training injury data were recorded using an online system by trained nominated injury recorders. Match exposure was also recorded.

RESULTS

Shoulder match injury incidence was 12.2 per 1000 h (95% CI, 9.1-16.2), with a mean severity of 47 days' time loss and an overall burden of 573 days per 1000 h. In total, 47 match and 5 training shoulder injuries were recorded. The most common injuries were shoulder dislocations/subluxations (34%), followed by acromioclavicular joint sprains (30%). Shoulder dislocations/subluxations represented the most burdensome injury (280 days per 1000 h). The tackle accounted for the majority (81%) of shoulder injuries. Forwards sustained a significantly higher incidence of shoulder injuries (8.3/1000 h) in comparison with backs (3.9/1000 h), with a rate ratio of 2.13 (95% CI, 1.15-3.94; P = .015).

CONCLUSION

We found a notably higher injury incidence rate in schoolboy rugby as compared with the adult amateur and professional game. Shoulder injuries were responsible for more days lost than any other injury, and shoulder dislocations were the most severe. This is of particular concern so early in a player's career and warrants further investigation into potential risk factors and mechanisms associated with shoulder injuries in school-age players.

Tackler and ball-carrier technique during moderate and severe injuries (≥8 days lost) compared with player-matched and team-matched injury-free controls in Elite Rugby Union

OBJECTIVE

To analyse tackler and ball-carrier technical proficiency during moderate and severe contact injuries (≥8 days lost) in professional rugby union, and compare it with injury-free event-matched controls from the same player and from the same team.

METHODS

Technical proficiency for 74 (n=74) (moderate and severe; ≥8 days lost) tackler and ball-carrier injuries during The Currie Cup (2014-2018) and 623 matched non-injury events (253 own controls, 370 team controls) were examined through video analysis using a standardised list of technical criteria.

RESULTS

Mean technical proficiency score for injured tacklers during front-on tackles was 6.19/16 (arbitrary units (AU) 95% CI 4.89 to 7.48), which was significantly different to their own controls (8.90/16 AU, 95% CI 8.37 to 9.43, p<0.001, effect size (ES)=1.21, large) and team controls (9.93/16 AU, 95% CI 9.50 to 10.40, p<0.001, ES=1.71, large). Mean technical proficiency score for injured ball-carriers during front-on tackles was 5.60/14 AU (95% CI 4.65 to 6.55), which was significantly different to their own controls (8.08/14 AU, 95% CI 7.56 to 8.60, p<0.001, ES=1.16, moderate) and team controls (8.16/14 AU, 95% CI 7.75 to 8.57, p<0.001, ES=1.25, large).

CONCLUSION

For the tackler and ball-carrier, for both front-on and side-on/behind tackles, overall technical proficiency scores were significantly lower for the injury-causing event, when compared with the player's own injury-free tackles and the team's injury-free tackles. Through analysing player and team controls, player technique deficiencies for the injured player and player technique deficiencies that expose all players to injury were highlighted, which may inform injury prevention strategies and policies, and assist coaches in optimising training to reduce tackle injury risk.

Incidence and Risk Factors in Concussion Events: A 5-Season Study in the French Top 14 Rugby Union Championship

BACKGROUND

Concussions are a source of major concern in rugby, and a limited number of studies have attempted to identify risk factors for these injuries.

PURPOSE

To investigate the incidence of match concussion and associated risk factors, including individual workload, anthropometric variables, playing position, and season phase, in elite rugby union players.

STUDY DESIGN

Case-control study; Level of evidence 3.

METHODS

All concussions and explanatory variables were collected for every match over 5 consecutive seasons (2014-2018) in 1334 professional players participating in the French Top 14 championship. Concussion risk was estimated using mixed effects Poisson regression.

RESULTS

Mean match concussion incidence equated to 10.4 (95% CI, 9.3-11.5) concussions for 1000 hours of game exposure. A peak was reached in the 2016-2017 season (13.7; 95% CI, 11.0-16.5). A greater risk was observed in the playoffs as compared with the first phase of the season (incidence rate ratio, 3.96; 95% CI, 2.10-7.35). In comparison with other positions, half-backs incurred the highest rate of concussion events (incidence, 16.1; 95% CI, 11.8-20.3). Irrespective of playing position, those with greater height and lower body mass reported a higher risk of concussions (P = .02), especially during tackling actions for lighter players (P = .01) and during other match events for taller players (P = .03). When adjusted for season phase, players who had accumulated a higher amount of playing time since the beginning of the season demonstrated a lower risk of concussion (P = .005).

CONCLUSION

Inter- and intraseasonal variations in concussion rates were observed. Within positional groups, lighter and taller players were more at risk, with the highest incidence generally observed in half-backs. Workload was measured by the number of matches played before a concussion event, and it appeared to have a protective rather than deleterious effect on concussion risk.

Returning to Play after Prolonged Training Restrictions in Professional Collision Sports

The COVID-19 pandemic in 2020 has resulted in widespread training disruption in many sports. Some athletes have access to facilities and equipment, while others have limited or no access, severely limiting their training practices. A primary concern is that the maintenance of key physical qualities (e. g. strength, power, high-speed running ability, acceleration, deceleration and change of direction), game-specific contact skills (e. g. tackling) and decision-making ability, are challenged, impacting performance and injury risk on resumption of training and competition. In extended periods of reduced training, without targeted intervention, changes in body composition and function can be profound. However, there are strategies that can dramatically mitigate potential losses, including resistance training to failure with lighter loads, plyometric training, exposure to high-speed running to ensure appropriate hamstring conditioning, and nutritional intervention. Athletes may require psychological support given the challenges associated with isolation and a change in regular training routine. While training restrictions may result in a decrease in some physical and psychological qualities, athletes can return in a positive state following an enforced period of rest and recovery. On return to training, the focus should be on progression of all aspects of training, taking into account the status of individual athletes.