Playing surface and UK professional rugby union injury risk

Artificial rugby union playing surface installation is increasing. This prospective cohort study aimed to examine the effect of playing surface on match injury types within 157 players of two UK professional rugby union clubs playing 209 matches (96 on artificial surfaces and 113 on grass) over three seasons. There was no difference in overall injury risk between the two playing surfaces with injury incidence on artificial 80.2 (CI 69.9–91.7) and on grass 81.9 per 1000 match-hours (CI 72.2–92.5), with an incidence rate ratio (RR) of 0.98 (CI 0.82–1.17). There was a higher rate of concussion (RR 0.52, CI 0.34 – 0.78) and chest injuries on grass (RR 0.26 CI 0.07, 0.95), and a higher rate of thigh haematoma (RR 2.25, CI 1.05–4.82) foot injuries (RR 4.12, CI 1.10, 15.40) and injury to players being tackled (RR 1.46, CI 1.00, 2.15) on artificial. Whilst there was no higher injury risk for matches played on artificial versus natural grass surfaces, the higher incidence of concussion and chest injury on grass, and the higher rate of foot injuries on artificial surfaces may be related to tackle and footwear-to-surface interface factors.     

Technical determinants of tackle and ruck performance in International rugby union

The most frequently occurring contact events in rugby union are the tackle and ruck. The ability repeatedly to engage and win the tackle and ruck has been associated with team success. To win the tackle and ruck, players have to perform specific techniques. These techniques have not been studied at the highest level of rugby union. Therefore, the purpose of this study was to identify technical determinants of tackle and ruck performance at the highest level of rugby union. A total of 4479 tackle and 2914 ruck events were coded for the Six Nations and Championship competitions. Relative risk ratio (RR), 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. Executing front-on tackles reduced the likelihood of offloads and tackle breaks in both competitions (Six Nations RR 3.0 Behind tackle, 95% confidence interval [95% CI]: 1.9–4.6, effect size [ES] = large, P < 0.001); Championship RR 2.9 Jersey tackle, 95% CI: 1.3–6.4, ES = moderate, P = 0.01). Fending during contact increased the chances of offloading and breaking the tackle in both competitions (Six Nations RR 4.5 Strong, 95% CI: 2.2–9.2, ES = large, P = P < 0.001; Championship RR 5.1 Moderate, 95% CI: 3.5–7.4, ES = large, P < 0.001). For the ruck, actively placing the ball increased the probability of maintaining possession (Six Nations RR 2.2, 95% CI: 1.1–4.3, ES = moderate, P = 0.03); Championship RR 4.0, 95% CI: 1.3–11.8, ES = large, P = 0.01). The techniques identified in this study should be incorporated and emphasised during training to prepare players for competition. Furthermore, these techniques need to be added to coaching manuals for the tackle and ruck.     

A kinematic analysis of the spine during rugby scrummaging on natural and synthetic turfs

Artificial surfaces are now an established alternative to grass (natural) surfaces in rugby union. Little is known, however, about their potential to reduce injury. This study characterises the spinal kinematics of rugby union hookers during scrummaging on third-generation synthetic (3G) and natural pitches. The spine was sectioned into five segments, with inertial sensors providing three-dimensional kinematic data sampled at 40 Hz/sensor. Twenty-two adult, male community club and university-level hookers were recruited. An equal number were analysed whilst scrummaging on natural or synthetic turf. Players scrummaging on synthetic turf demonstrated less angular velocity in the lower thoracic spine for right and left lateral bending and right rotation. The general reduction in the range of motion and velocities, extrapolated over a prolonged playing career, may mean that the synthetic turf could result in fewer degenerative injuries. It should be noted, however, that this conclusion considers only the scrummaging scenario.     

Spatial characterisation of natural and third-generation artificial turf football pitches

In contrast to the situation with early artificial turf pitches, little information has previously been published on the characterisation of third-generation artificial surfaces. The spatial variation of ball rebound resilience and rotational resistance were measured here under dry conditions, late in the season, for two natural turf football pitches and a recently laid third-generation artificial turf pitch. Data for the natural turf pitches show a wider variation with position on the pitch than for the artificial pitch. The latter surface showed remarkable consistency in both quantities measured. Surprisingly, all ball rebound resilience data and some of the rotational resistance values were found to lie outside current FIFA specifications, possibly due to the level of wear in natural turf at this stage of the season. For the artificial turf, the deterioration in properties over a period of 6 months is significant and suggests more frequent testing is needed. Taking data from various pitch positions, the two measured quantities were shown for the first time, as far as we are aware, to be inversely related for both natural turf pitches. This correlation may be largely attributed to differences in the extent of grass cover and/or soil compaction. For artificial turf, the lack of variation in measured quantities with pitch position precluded the determination of any correlation.     

The effect of ball-carrying technique and experience on sprinting in rugby union

Abstract

There are several ways of carrying the ball in rugby union, which could influence the speed at which a player can run. We assessed 52 rugby players (34 males, 18 females) during a maximum sprint over 30 m without the ball, with the ball under one arm, and with the ball in both hands. Timing gates were used to measure time over the initial 10 m and the last 20 m. It has previously been reported (Grant et al., 2003 Grant, S. J., Oommen, G., McColl, G., Taylor, J., Watkins, L.Friel, N. 2003. The effects of ball carrying method on sprint speed in rugby union football players. Journal of Sports Sciences, 21: 1009–1015. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) that running with the ball produces a slower sprinting speed than running without the ball. We hypothesized that the decrease in speed caused by carrying the ball would become less marked with the experience of the player. The male and female players were each divided into two groups: a “beginner” group that consisted of players in their first or second season and an “experienced” group that was composed of players who had played for more than two seasons. A 2 × 3 mixed-model analysis of variance was used to identify differences (P < 0.01) between the beginner and experienced groups in the three sprinting conditions. The times for the males for the first 10 m sprints without the ball, with the ball under one arm, and with the ball in both hands were 1.87 ± 0.08 s, 1.87 ± 0.08 s, and 1.91 ± 0.1 s for the beginners, and 1.87 ± 0.1, 1.88 ± 0.1 and 1.88 ± 0.12 for the more experienced players respectively. The times for the females for the first 10 m without the ball, with the ball under one arm, and with the ball in both hands were 2.13 ± 0.16 s, 2.19 ± 0.17 s, and 2.20 ± 0.16 s for the beginners, and 2.03 ± 0.12 s, 2.03 ± 0.09 s, and 2.04 ± 0.1 s for the more experienced players respectively. For the last 20 m of the 30-m sprint, there were differences between the different sprint conditions (P < 0.001) but no differences that were attributable to experience (P = 0.297). The times for the males over the last 20 m without the ball, with the ball under one arm, and with the ball in both hands were 2.58 ± 0.19 s, 2.61 ± 0.12 s, and 2.65 ± 0.12 s for the beginners, and 2.59 ± 0.12, 2.62 ± 0.23, and 2.65 ± 0.18 s for the more experienced players respectively. The times for the females over the last 20 m without the ball, with the ball under one arm, and with the ball in both hands were 3.25 ± 0.38 s, 3.35 ± 0.42 s, and 3.40 ± 0.46 s for the beginners, and 3.04 ± 0.32 s, 3.06 ± 0.22 s, and 3.13 ± 0.27 s for the more experienced players respectively. No gender-specific differences were detected. The results of this study suggest that practising sprints while carrying a ball benefits the early phase of sprinting while carrying the ball.     

Influence of the composition of artificial turf on rotational traction and athlete biomechanics

Artificial turf advances have enabled surfaces to behave like natural grass, however, debate remains as to whether artificial turf is as safe as natural grass. To reduce injury risk, sport surfaces should have low rotational traction with artificial surfaces having a potential advantage as components can be manipulated to change surface properties and traction. The purpose of this study was to investigate the influence that different components of artificial turf have on rotational traction and athlete lower extremity joint loading. Twelve surfaces underwent mechanical testing to determine the influence of fibre density, fibre length, infill composition and compaction on rotational traction. Following mechanical testing, Control, Low and High Traction surfaces were selected for biomechanical analysis, where sixteen athletes performed maximum effort v-cuts while kinematic/kinetic data were recorded on each surface. Mechanically, fibre density, type of infill and compaction of the surface each independently influenced traction. The traction differences were substantial enough to alter the athlete kinematics and kinetics. Low traction surfaces reduced ankle and knee loading, while high traction surfaces increased ankle and knee loading . Reducing the rotational traction of sport surfaces is possible through alterations of individual components, which may reduce the joint loading at the knee and ankle joint.     

The predicted risk of head injury from fall-related impacts on to third-generation artificial turf and grass soccer surfaces: A comparative biomechanical analysis

The risk of soccer players sustaining mild traumatic brain injury (MTBI) following head impact with a playing surface is unclear. This study investigates MTBI by performing headform impact tests from varying heights onto a range of third-generation artificial turf surfaces. Each turf was prepared as per manufacturers specifications within a laboratory, before being tested immediately following installation and then again after a bedding-in period. Each turf was tested dry and when wetted to saturation. Data from the laboratory tests were compared to an in situ third-generation surface and a professional grass surface. The surface performance threshold was set at a head impact criterion (HIC) = 400, which equates to a 10% risk of the head impact causing MTBI. All six third-generation surfaces had a >10% risk of MTBI from a fall >0.77 m; the inferior surfaces required a fall from just 0.46 m to have a 10% MTBI risk. Wetting the artificial turf did not produce a statistically significant improvement (P > 0.01). The in situ third-generation playing surface produced HIC values within the range of bedded-in experimental values. However, the natural turf pitch was the superior performer – necessitating fall heights exceeding those achievable during games to achieve HIC = 400.     

The kinetics of rugby union scrummaging

Two rugby union forward packs of differing ability levels were examined during scrummaging against an instrumented scrum machine. By systematically moving the front‐row of the scrum along the scrum machine, kinetic data on each front‐row forward could be obtained under all test conditions. Each forward pack was tested under the following scrummaging combinations: front‐row only; front‐row plus second‐row; full scrum minus side‐row, and full scrum. Data obtained from each scrum included the three orthogonal components of force at engagement and the sustained force applied by each front‐row player. An estimate of sub‐unit contributions was made by subtracting the total forward force on all three front‐row players from the total for the complete scrum. Results indicated the primary role of the second‐row appeared to be application of forward force. The back‐row ('number eight') forward did not substantially contribute any additional forward force, and added only slightly to the lateral and vertical shear force experienced by the front‐row. The side‐row contributed an additional 20–27% to the forward force, but at the expense of increased vertical forces on all front‐row forwards. Results of this investigation are discussed in relation to rule modification, rule interpretation and coaching.     

The effect of ball carrying method on sprint speed in rugby union football players

Different methods of ball carrying can be used when a player runs with the ball in rugby union. We examined how three methods of ball carrying influenced sprinting speed: using both hands, under the left arm and under the right arm. These methods were compared with running without the ball. Our aim was to determine which method of ball carrying optimizes sprinting speed. Altogether, 48 rugby union players (age 21±2 years, height 1.83±0.1?m, body mass 85.3±12?kg, body fat 14?±?5%; mean±s) were recruited. The players performed twelve 30-m sprints in total (each player performed three trials under each of three methods of carrying the ball and sprinting without the ball). The design of the study was a form of Latin rectangle, balanced across the trial order for each of the methods and for pairwise combinations of the methods in blocks of four per trial. Each sprint consisted of a 10-m rolling start, followed by a 20-m timed section using electronic timing gates. Compared with sprinting 20?m without the ball (2.58±0.16?s), using both hands (2.62±0.16?s) led to a significantly slower time (P?<0.05). Sprinting 20?m with the ball under the left arm (2.61±0.15?s) or under the right arm (2.60± 0.17?s) was significantly quicker than when using ‘both hands’ (P?<0.05), and both these methods were significantly slower than when running without the ball (P?<0.05). Accordingly, running with the ball in both hands led to the greatest decrement in sprinting performance, although carrying the ball under one arm also reduced the players' sprinting ability. Our results indicate that to gain a speed advantage players should carry the ball under one arm.     

Effect of turf on the cutting movement of female football players

PurposeThe globalisation of artificial turf and the increase in player participation has driven the need to examine injury risk in the sport of football. The purpose of this study was to investigate the surface–player interaction in female football players between natural and artificial turf.MethodsEight university level female football players performed an unanticipated cutting manoeuvre at an angle of 30° and 60°, on a regulation natural grass pitch (NT) and a 3G artificial turf pitch (AT). An automated active maker system (CodaSport CXS System, 200 Hz) quantified 3D joint angles at the ankle and knee during the early deceleration phase of the cutting, defined from foot strike to weight acceptance at 20% of the stance phase. Differences were statistically examined using a two-way (cutting angle, surface) ANOVA, with an α level of p < 0.05 and Cohen's d effect size reported.ResultsA trend was observed on the AT, with a reduction in knee valgus and internal rotation, suggesting a reduced risk of knee injury. This findings highlight that AT is no worse than NT and may have the potential to reduce the risk of knee injury. The ankle joint during foot strike showed large effects for an increase dorsiflexion and inversion on AT. A large effect for an increase during weight acceptance was observed for ankle inversion and external rotation on AT.ConclusionThese findings provide some support for the use of AT in female football, with no evidence to suggests that there is an increased risk of injury when performing on an artificial turf. The ankle response was less clear and further research is warranted. This initial study provides a platform for more detailed analysis, and highlights the importance of exploring the biomechanical changes in performance and injury risk with the introduction of AT.     

The effects of a rugby playing season on cervical range of motion

Abstract

Rugby players have a reduced active cervical range of motion (ACROM) mid-season compared with age-matched controls. This is most evident in rugby forwards, who have ACROM similar to patients with acute whiplash. This study aims to show if the change in ACROM over an entire rugby season (pre-, mid-, and end of season) shows a pattern of decline. A cross-sectional study of 22 rugby players (11 backs aged 24.9 ± 1.3 years; 11 forwards aged 24.5 ± 1.1 years) from elite English Premiership clubs had their cervical range of motion measured for flexion, extension, left and right side flexion, plus left and right rotation with a cervical range of motion device. The percentage change between start to mid-season, mid- to end of season, and start to end of season were calculated. Group means were compared for absolute ACROM (degrees) and percentage change over the season. The percentage change indicated a decrease in ACROM over the rugby playing season, with most of the decrement occurring in the second half of the season. Most of the relative change was observed in right lateral flexion, while rotation did not change significantly. In conclusion, ACROM declines throughout the playing season, which requires attention in terms of training and rehabilitation.     

Comprehensive evaluation of player-surface interaction on artificial soccer turf

The purpose of this study was to evaluate the traction characteristics of four different stud configurations on Fédération Internationale de Football Association (FIFA) 2-Star, third-generation artificial soccer turf. The investigated stud configurations were hard ground design, firm ground design, soft ground design, and an experimental prototype. The concept of this study combines performance, perception, biomechanical, and mechanical testing procedures. Twenty-five soccer players took part in the different testing procedures. Variables of this study were: running times, subjective rankings/ratings, ground reaction forces, and mechanical traction properties. Statistical discrimination between the four stud configurations was shown for performance, perception, and biomechanical testing (p < 0.05). Unsuited stud configurations for playing on artificial turf are characterized by less plain distributed and pronounced studs.     

Effects of structural components of artificial turf on the transmission of impacts in football players

The third generation of artificial turf systems (ATS) has matched the mechanical behaviour of natural grass, but today a high heterogeneity at structural level and mechanical behaviour in the new ATS also exists. The objective was to analyse the effect of the structural components of ATS football pitches and running speed on the capacity of impact attenuation. A total of 12 athletes were evaluated at three speed conditions (3.33 m/s, 4 m/s and maximum speed) on four different ATS, classifying them by their components (length of fibre, type of in-fill and sub-base). Impact attenuation was significantly higher in ATS3, characterised by longer fibre compared to other ATS with less fibre length. The ATS4 with a higher length fibre and built on compacted granular material proportioned significantly lower values in the maximum peaks of tibia acceleration. Finally, as speed increases, the peak tibia impacts were significantly higher. Longer fibre length and the capacity to accommodate a higher quantity of infill facilitate higher impact attenuation. Equally, a compacted granular sub-base is related to lower magnitude of maximum tibia peaks. Finally, the magnitude of the tibia acceleration peaks is dependent of running speed for all ATS analysed, being higher as speed increases.     

不同颗粒密度人造草坪对足球运动员运动表现及损伤的影响

目的:揭示人造草坪不同颗粒填充密度对足球运动员侧切和起动动作表现的影响,并通过动作过程的生物力学数据分析可能的损伤危险。方法:13名男子足球运动员分别在3种不同颗粒密度的人造草坪上进行45°侧切和直线起动动作,采集运动学和动力学数据。结果:随着颗粒密度的增加,鞋与草坪交互面牵引力增大;侧切制动阶段地面反作用力峰值和加载率增大,地面反作用力首次峰值时刻的垂直、前、后分力增大,膝伸力矩增大,内收力矩和外展角度减小;蹬伸阶段地面反作用力分量增大;直线起动的重心加速度无显著差异。结论:鞋与人造草坪交互面的牵引力随填充颗粒的密度增加而增加;在常速助跑情况下,较大的交互面牵引力可以为侧切提供良好的制动能力和蹬伸推进力,但不会对直线起动的运动表现造成影响;交互面牵引力的增大会引起侧切制动阶段地面反作用力相关指标的增大,造成地面反作用力峰值时刻ACL损伤敏感指标的改变,导致更大的损伤风险。     

论学校体育伤害事故的风险管理

针对学校体育伤害事故发生的可能性与严重程度,引入风险管理理论,认为制定学校体育伤害事故的风险管理计划主要包括成立风险管理小组、分析风险和确定控制方法、法律分析与政策陈述、操作行为和程序,执行与监督等,阐述了风险管理在学校体育伤害风险分析与控制方法的具体应用:风险识别、风险评估、风险应对等,明确了学校体育伤害事故的责任,提出了风险管理的操作行为和程序、执行与监督等问题.     

自由式滑雪运动损伤风险研究

基于2006~2014赛季国际滑雪联合会损伤健康系统(FIS ISS)最新伤病报告数据,对自由式滑雪运动损伤类型、损伤严重程度、损伤部分等进行分析,得出自由式滑雪运动员最容易受伤部位是膝盖、头部、脸部、髋部,容易受伤的类型是关节与韧带损伤、骨折与应力性骨折、脑震荡等。从自由式滑雪专项特征、比赛要求、场地与器械、训练等方面分析导致损伤的风险因素,提出规避和降低损伤风险的建议。     

运动员伤病风险的社会法规制:源起、规范与完善

运动员在训练和比赛过程中遭遇的伤病风险属职业风险范畴,虽属个人风险,但具有社会性,运动员伤病风险应纳入社会保险保障范围。肇因于运动员"伤与病"的纠缠,运动员伤病风险的社会法规制路径一直摇摆不定。随着运动员职业化改革的推进,运动员伤病风险与工伤保险的同构性以及与医疗保险的异质性共同昭示了运动员伤病风险的工伤保险保障路径。社会法规制效果的彰显需要通过运动员伤病风险保障的理念更新、规范创制和制度协调共同推进。     

运动员伤病风险的社会法规制:源起、规范与完善

运动员在训练和比赛过程中遭遇的伤病风险属职业风险范畴，虽属个人风险，但具有社会性，运动员伤病风险应纳入社会保险保障范围。肇因于运动员"伤与病"的纠缠，运动员伤病风险的社会法规制路径一直摇摆不定。随着运动员职业化改革的推进，运动员伤病风险与工伤保险的同构性以及与医疗保险的异质性共同昭示了运动员伤病风险的工伤保险保障路径。社会法规制效果的彰显需要通过运动员伤病风险保障的理念更新、规范创制和制度协调共同推进。     

鞭腿技术引发踝关节外侧副韧带急性损伤风险的运动学特征分析

目的通过观察不同运动等级散打运动员在使用鞭腿技术动作时,支撑腿踝关节运动学特征所出现的差异,探求运动学特征与外侧副韧带急性损伤风险的关系。方法运用VICON Nexus 3D红外运动捕捉系统和Kistler地面测力系统,对23名不同运动等级男子散打运动员在使用鞭腿技术时支撑腿踝关节的动作轨迹进行采集,依据运动链原理将运动轨迹划分为启动、击打、回收3个时段,利用VICON Polygon分析软件对每个时段踝关节的角度、角速度、位移、时间、速度等特征进行分析。结果在击打过程中,不同运动等级运动员踝关节的运动方向一致,踝关节的活动度却出现了差异,启动和回收时段的内翻角度存在显著性(P<0.05);一般运动员踝关节的动作时间、位移均大于优秀运动员,启动时段的动作时间、上下位移、动作速度存在显著性(P<0.05)。结论不同运动等级散打运动员支撑腿踝关节的运动学特征存在显著性差异,优秀运动员踝关节运动轨迹的稳定性整体上好于一般运动员;运动学特征与引发外侧副韧带急性损伤风险存有关联,一般运动员因踝关节活动度相对较大,引发外侧副韧带急性损伤的风险也相对较高;启动时段是引发踝关节外侧副韧带急性损伤风险的最大时段。