Sharief Hendricks

Tackling in Rugby: Coaching Strategies for Effective Technique and Injury Prevention

The high impact and physical nature of the tackle during a rugby match places the tackler(s) and ball-carrier at risk of injury. Injuries as a result of the tackle account for up to 61% of all injuries that occur during a rugby match. The purpose of this paper is to: i) review the literature on tackle injury mechanisms and events associated with increased risk of injury during the tackle; and ii) identify strategies that can be coached during training and executed by players during a match to reduce the risk of injury. Coaches equipped with a better understanding of injury mechanisms and a thorough knowledge of a safe and effective technique in the tackle have a major role in preventing or reducing tackle injuries.

Tackler characteristics associated with tackle performance in rugby union

Abstract Tackling is an important skill for performance in rugby, yet little has been reported on tackler characteristics and its relationship to performance in competition. The aim of this study was to identify tackler characteristics and its association with tackle performance in matches. Eighteen matches of the 2010 Super 14 were analysed, which amounted to 2092 coded tackles. Tackler characteristics such as head position – in motion, up and forward, type of tackle – shoulder tackler, arm tackle or ball-carrier fend – absent, moderate, strong and leg drive–absent, moderate, strong or shoulder usage were coded and associated with tackle outcomes. Relative risk ratio (RRR), the ratio of the probability of an outcome occurring when a characteristic was observed (versus the non-observed characteristic) was determined using multinomial logistic regression. Having the head in motion decreased the tacklers chances of a successful tackle (RRR 2.24, 95% CI 1.72–2.92, p < 0.001) relative to an up and forward head position. Ball-carriers using a fend significantly decreased the tacklers probability of success (moderate fend RRR 2.97, 95% CI 2.04–4.31, p < 0.001). Moderate leg drive (RRR 0.36, 95% CI 0.26–0.50, p < 0.001) by the tackler increased the likelihood of tackle success. Head up and forward, counter-acting the ball-carrier fend, shoulder tackles targeted at the ball-carrier mid-torso, using the arms to wrap or pull, and leg driving were key tackler characteristics associated with positive tackle outcome in matches. Based on these findings, it is recommended that these technical characteristics are emphasised and incorporated into training to effectively prepare tacklers for competition.

Tackle technique and tackle-related injuries in high-level South African Rugby Union under-18 players: real-match video analysis

Background The high injury rate associated with rugby union is primarily due to the tackle, and poor contact technique has been identified as a risk factor for injury. We aimed to determine whether the tackle technique proficiency scores were different in injurious tackles versus tackles that did not result in injury using real-match scenarios in high-level youth rugby union. Methods Injury surveillance was conducted at the under-18 Craven Week tournaments (2011–2013). Tackle-related injury information was used to identify injury events in the match video footage and non-injury events were identified for the injured player cohort. Injury and non-injury events were scored for technique proficiency and Cohens effect sizes were calculated and the Student t test (p<0.05) was performed to compare injury versus non-injury scores. Results The overall mean score for front-on ball-carrier proficiency was 7.17±1.90 and 9.02±2.15 for injury and non-injury tackle events, respectively (effect size=moderate; p<0.05). The overall mean score for side/behind ball-carrier proficiency was 4.09±2.12 and 7.68±1.72 for injury and non-injury tackle events, respectively (effect size=large; p<0.01). The overall mean score for front-on tackler proficiency was 7.00±1.95 and 9.35±2.56 for injury and non-injury tackle events, respectively (effect size=moderate; p<0.05). The overall mean score for side/behind tackler proficiency was 5.47±1.60 and 8.14±1.75 for injury and non-injury tackle events, respectively (effect size=large; p<0.01). Summary Higher overall mean and criterion-specific tackle-related technique scores were associated with a non-injury outcome. The ability to perform well during tackle events may decrease the risk of injury and may manifest in superior performance.

Velocity and acceleration before contact in the tackle during rugby union matches

Abstract The velocity and acceleration at which the ball-carrier or tackler enters the tackle may contribute to winning the contest and prevailing injury free. Velocity and acceleration have been quantified in controlled settings, whereas in match-play it has been subjectively described. The purpose of this study was to determine the velocity and acceleration of the ball-carrier and tackler before contact during match-play in three competitions (Super 14, Varsity Cup, and Under-19 Currie Cup). Using a two-dimensional scaled version of the field, the velocity and acceleration of the ball-carrier and tackler were measured at every 0.1 s to contact for 0.5 s. For front-on tackles, a significant difference (P < 0.05) between the ball-carrier (4.6 ± 1 m · s–1) and tackler (7.1 ± 3.5 m · s–1) was found at the 0.5 s time to contact interval in the Varsity Cup. For side-on tackles, differences between the two opposing players were found at 0.5 s (ball-carrier: 4.6 ± 1.7 m · s–1; tackler: 3.1 ± 1.2 m · s–1) and 0.4 s (ball-carrier: 6.3 ± 2.3 m · s–1; tackler: 3.7 ± 1.6 m · s–1) at Under-19 level. After 0.4 s, no significant differences (P > 0.05) were evident. Also, the ball-carriers velocity over the 0.5 s was relatively stable compared with that of the tackler. Results suggest that tacklers adjust their velocity to reach a suitable relative velocity before making contact with the ball-carrier.

Contact technique and concussions in the South African under-18 Coca-Cola Craven Week Rugby tournament

Abstract In rugby union, understanding the techniques and events leading to concussions is important because of the nature of the injury and the severity and potential long-term consequences, particularly in junior players. Proper contact technique is a prerequisite for successful participation in rugby and is a major factor associated with injury. However, the execution of proper contact technique and its relationship to injury has yet to be studied in matches. Therefore, the aim of this study was to compare contact techniques leading to concussion with a representative sample of similarly matched non-injury (NI) contact events. Injury surveillance was conducted at the 2011–2013 under-18 Craven Week Rugby tournaments. Video footage of 10 concussive events (5 tackle, 4 ruck and 1 aerial collision) and 83 NI events were identified (19 tackle, 61 ruck and 3 aerial collisions). Thereafter, each phase of play was analysed using standardised technical proficiency criteria. Overall score for ruck proficiency in concussive events was 5.67 (out of a total of 15) vs. 6.98 for NI events (n = 54) (effect size = 0.52, small). Overall average score for tackler proficiency was 7.25 (n = 4) and 6.67 (n = 15) for injury and NI tackles, respectively (out of 16) (effect size = 0.19, trivial). This is the first study to compare concussion injury contact technique to a player-matched sample of NI contact techniques. Certain individual technical criteria had an effect towards an NI outcome, and others had an effect towards a concussive event, highlighting that failure to execute certain techniques may substantially increase the opportunity for concussion.

Tackle-related injury rates and nature of injuries in South African Youth Week tournament rugby union players (under-13 to under-18): an observational cohort study

Objectives The tackle situation is most often associated with the high injury rates in rugby union. Tackle injury epidemiology in rugby union has previously been focused on senior cohorts but less is known about younger cohorts. The aim of this study was to report on the nature and rates of tackle-related injuries in South African youth rugby union players representing their provinces at national tournaments. Design Observational cohort study. Setting Four South African Youth Week tournaments (under-13 Craven Week, under-16 Grant Khomo Week, under-18 Academy Week, under-18 Craven Week). Participants Injury data were collected from 3652 youth rugby union players (population at risk) in 2011 and 2012. Outcome measures Tackle-related injury severity (‘time-loss’ and ‘medical attention’), type and location, injury rate per 1000 h (including 95% CIs). Injury rate ratios (IRR) were calculated and modelled using a Poisson regression. A χ2 analysis was used to detect linear trends between injuries and increasing match quarters. Results The 2012 under-13 Craven Week had a significantly greater ‘time-loss’ injury rate when compared with the 2012 under-18 Academy Week (IRR=4.43; 95% CI 2.13 to 9.21, p<0.05) and under-18 Craven Week (IRR=3.52; 95% CI 1.54 to 8.00, p<0.05). The Poisson regression also revealed a higher probability of ‘overall’ (‘time-loss’ and ‘medical attention’ combined) and ‘time-loss’ tackle-related injuries occurring at the under-13 Craven Week. The proportion of ‘overall’ and ‘time-loss’ injuries increased significantly with each quarter of the match when all four tournaments were combined (p<0.05). Conclusions There was a difference in the tackle-related injury rate between the under-13 tournament and the two under-18 tournaments, and the tackle-related injury rate was higher in the final quarter of matches. Ongoing injury surveillance is required to better interpret these findings. Injury prevention strategies targeting the tackle may only be effective once the rate and nature of injuries have been accurately determined.

An evidence-driven approach to scrum law modifications in amateur rugby played in South Africa

Background In 2012, the South African Rugby Union (SARU) approved a new set of scrum laws for amateur rugby played in the country, to be implemented at the start of the 2013 rugby season. These law changes were primarily based on the relatively high proportion of scrum-related catastrophic injury data collected as part of the BokSmart National Rugby Safety Programme (BokSmart) over the preceding 4 years (2008–2011). Aim To describe the scrum-related catastrophic injury data in South Africa over the past 5 years (2008–2012), and to discuss how this evidence justifies the change in the Amateur Scrum Laws to make this aspect of the game safer in South Africa. Methods Catastrophic injury data were collected through BokSmart at amateur and professional levels, during training and matches over 5 years (2008–2012). Results The scrum phase accounted for 33% (n=20 of 60) of all catastrophic injuries between 2008 and 2012. Eighteen of the 20 scrum injuries (90%) were confirmed as acute spinal cord injuries, with 13 of these being permanent injuries. For the scrum injury mechanisms that were provided (n=19), ‘impact on the engagement’ was the most frequently reported (n=11 of 19, 58%), followed by ‘collapsed scrum’ (n=7 of 19, 37%) and ‘popping out’ (n=1 of 19, 5%). Conclusions Based on these scrum-related catastrophic injury data, a change in the Amateur Scrum Laws of South African Rugby was justified. The main purpose of these scrum law changes is to reduce the number of scrum-related catastrophic injuries in the country, by minimising the opportunity for impact injury and subsequent scrum collapse in amateur rugby in South Africa, thereby making this aspect of the game of rugby safer.

Defensive strategies in rugby union

Success in rugby union competition is dependent partly on the defensive strategies of a team. Despite this, little empirical evidence exists about effective defensive strategies used during play. This study attempted to identify defensive characteristics associated with increased likelihood of a successful outcome in rugby union, while considering the game situation. Twenty-one matches of the 2010 Super 14 competition were analysed, amounting to 2,394 coded tackle contacts. The likelihood of the defending team winning the breakdown (the post-tackle contact situation where opposing teams compete for possession of the ball) increased as the match progressed. Defensive speed, measured as the speed of the defence in response to the attacking line, was a statistically significant predictor of breakdown wins and preventing the attacking team from advancing towards the gain line. Identifying the relative effectiveness of such strategies allows understanding of rugby match behaviour and may be applied to improve organisation, design, training, teaching and learning the game.

Mechanisms and Factors Associated With Tackle-Related Injuries in South African Youth Rugby Union Players:

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.

Incidence and Factors Associated With Concussion Injuries at the 2011 to 2014 South African Rugby Union Youth Week Tournaments.

Objective:To determine the concussion incidence and to identify factors associated with concussion in South African youth rugby union players. Design:Prospective cohort study. Setting:Injury surveillance was completed at the South African Rugby Union Youth Week tournaments (under-13, under-16, and under-18 age groups). Participants:South African youth rugby union players. A total of 7216 players participated in 531 matches between 2011 and 2014. Interventions:None. Main Outcome Measures:Concussion incidence was calculated per 1000 player-match-hours with 95% CIs. Poisson regression was used to calculate the incidence rate ratio (IRR) between factors (age, time period, playing position, and activity at the time of concussion) potentially associated with concussions. Results:The concussion incidence was 6.8/1000 player-match-hours (95% CI, 5.5-8.1) across all age groups. Under-13s (IRR, 1.5; P = 0.09) and under-16s (IRR, 1.7; P = 0.03) had higher concussion incidence rates than the under-18 age group. The incidence was higher in the third (IRR, 2.1; P = 0.04) and fourth (IRR, 2.5; P = 0.01) quarters of matches compared with the first quarter. Sixty-two percent of concussions occurred in the tackle situation. The tackler had a 4-fold greater concussion rate (IRR, 4.3; P < 0.001) compared with the ball carrier. The hooker and loose forwards had higher incidence rates than several other player positions (P < 0.05). Conclusions:The reported concussion incidence falls within the broad range previously reported in youth rugby. The evidence highlighted in this study may contribute to targeted concussion prevention strategies and provide a baseline against which the effectiveness of future interventions can be measured.