Player and match characteristics associated with head acceleration events in elite-level men's and women's rugby union matches.

Objective: To examine the likelihood of head acceleration events (HAEs) as a function of previously identified risk factors: match time, player status (starter or substitute) and pitch location in elite-level men's and women's rugby union matches. Methods: Instrumented mouthguard data were collected from 179 and 107 players in the men's and women's games and synchronised to video-coded match footage. Head peak resultant linear acceleration (PLA) and peak resultant angular acceleration were extracted from each HAE. Field location was determined for HAEs linked to a tackle, carry or ruck. HAE incidence was calculated per player hour across PLA recording thresholds with 95% CIs estimated. Propensity was calculated as the percentage of contact events that caused HAEs across PLA recording thresholds, with a 95% CI estimated. Significance was assessed by non-overlapping 95% CIs. Results: 29 099 and 6277 HAEs were collected from 1214 and 577 player-matches in the men's and women's games. No significant differences in match quarter HAE incidence or propensity were found. Substitutes had higher HAE incidence than starters at lower PLA recording thresholds for men but similar HAE propensity. HAEs were more likely to occur in field locations with high contact event occurrence. Conclusion: Strategies to reduce HAE incidence need not consider match time or status as a substitute or starter as HAE rates are similar throughout matches, without differences in propensity between starters and substitutes. HAE incidence is proportional to contact frequency, and strategies that reduce either frequency or propensity for contact to cause head contact may be explored.

Pain, impairment, medication use and health-related quality of life of retired professional rugby players.

Background: Rugby is a physically demanding sport with a high injury rate. Professional male rugby players have a notably greater risk of sustaining injuries that require hospitalisation or surgery than male athletes from non-contact sports. Retired elite male rugby players experience physical and mental health conditions as well as varying levels of pain, negatively impacting their quality of life. Retired rugby players could use medication or substances as a coping mechanism to deal with chronic pain and a lower quality of life. However, research is scarce on how retired rugby players manage pain and how this affects their quality of life. Objectives: This study aimed to understand joint pain and impairment, mental and physical quality of life, and pain medication use in retired professional male rugby players. Methods: A cross-sectional study was conducted using a questionnaire completed by retired professional male rugby players. Joint pain and impairment were explored through three questions, health-related quality of life was assessed through the PROMIS-GH, and medication use was explored through 12 questions. Results: Retired rugby players (N=142) reported higher scores than matched controls (N=49) for joint pain and impairment, including significantly higher scores for joint impairments for activities of daily living (p=0.047). The global mental health scores of retired rugby players were significantly lower compared to matched controls (p=0.043) and the global physical health scores were also lower in retired rugby players. Most retired rugby players reported not using prescription pain medication (75%) or over-the-counter pain medication (56%). Conclusion: Professional rugby careers have a considerable impact on the joint health and overall well-being of retired players, resulting in unique challenges. The findings of this study emphasise the need for specific after-career support for challenges faced by retired rugby players.

The Impact of Pressure Training on the Performance of Semi-Professional Female Rugby League Players.

BACKGROUND: The aim of this study was to examine the effect of pressure training on the performance of semi-professional female rugby league athletes. METHODS: Using a within-subjects design, 16 female athletes (19.9 ± 3.4 years) performed a passing accuracy task under three conditions; (1) a control condition; (2) a physiological fatigue condition; and (3) a threat of consequence condition. Passing performance, perceived pressure, rate of perceived exertion (RPE), and self-confidence were assessed. RESULTS: A significant main effect of conditions was found for rate of perceived exertion (p < 0.001), self-confidence (p < 0.028), and perceived pressure (p = 0.011). There was no main effect of condition on passing performance. Post hoc comparisons revealed that RPE was significantly higher in the physiological fatigue condition when compared to the control (p = 0.009) and threat of consequence conditions (p < 0.001). Perceived pressure was significantly higher in the threat of consequence condition compared to the control condition (p = 0.037). CONCLUSIONS: The main findings of this study are that (1) passing performance was not impacted by pressure training conditions, and (2) threats of consequences are an effective manipulation to generate pressure in female semi-professional rugby league players. These results offer nuanced insights into the impact of pressure generation in training environments for female semi-professional rugby league athletes.

Energy Balance and Dietary Intake in Young Rugby Players during a Pre-Season Micro-Cycle: A Cluster Analysis.

Rugby players must develop excellent levels of conditioning during adolescence. However, this pivotal period of life is also characterized by a surge in biological growth, which further increases the energy and nutritional requirements of this population. This study examined within-individual differences in energy intake (EI) and energy balance (EB) of 46 young rugby players during a pre-season micro-cycle. Two clusters were identified with significantly different characteristics and EB states, suggesting that young rugby players adjust their EI to match their body composition goals. The first cluster is characterized by players with a low body fat% (12.87 ± 2.53). They had a positive EB (330 ± 517 kcal), suggesting a goal of increasing muscle mass. Conversely, the second cluster is characterized by a higher body fat% (23.1 ± 1.6, p < 0.005) and reported a negative, lower EB (-683 ± 425 kcal, p < 0.005), suggesting a goal focused on reducing fat mass. Although our study provides more optimistic results than previous ones regarding the high risk of inadequate EI in young rugby players, we emphasize the importance of rigorous nutritional support, especially for players aiming to lose weight, to avoid severe caloric restriction, as well as the downstream effects of such practices on their nutritional status, given the higher risk of macro- (e.g., CHO < 6 g/kg/d) and micronutrient (e.g., iron < 11 mg/d, calcium < 1300 mg/d, vitamin D < 5 mg/d) deficiencies.

Contemporary Themes in Dietary Intake in Rugby Union Players: A Narrative Review.

Rugby union is an intermittent team sport with variability in body composition and match-play demands between positions which requires careful consideration for individual dietary requirements. While previous reviews have detailed the macronutrient intake in rugby players, none have discussed the further determinants of dietary intake in this population. Therefore, the purpose of the current review was to summarise the current evidence detailing dietary intake in rugby union players, report on contemporary nutritional research themes, and provide recommendations for athletes, nutritionists, and other stakeholders. In total, eighteen articles report on dietary intake in rugby players, with only one of these detailing dietary intake in female athletes. Recent studies have reported on both protein and carbohydrate periodisation practices in rugby union players; however, there is currently limited evidence as to the influence of these on performance, recovery, and well-being. Factors influencing eating patterns, the impact of sports nutritionists on dietary intake, and food consumption in catered and non-catered environments has been explored in isolated studies. Nutrition knowledge levels in rugby players have been reported in several studies; however, the influence this has on dietary intake in rugby players is unknown. Collectively, despite new contemporary themes emerging in the literature concerning dietary intake in rugby players, the studies are isolated; as such, there is limited scope to the translatability of information due to heterogeneity in sex, level of play, and location of participants. Given this, future research should aim to build upon the themes identified in this review in combination to support practitioners working within their specific environments. This will subsequently build towards the generation of rugby-specific recommendations.

The influence of external loads on post-match neuromuscular fatigue in international rugby union: A partial least squares correlational analysis.

The aims were to determine the relationship(s) between match-play external load and post-match neuromuscular fatigue as latent constructs, the contribution of the specific measured variables to these latent constructs, and how these differ between forwards and backs in elite rugby union. Forty-one elite male rugby union players (22 forwards and 19 backs) from the same international rugby union team were tested, with data included from the 2020 and 2021 international seasons (11 matches; 146 player appearances). Player's match-play external loads were quantified using microtechnology (for locomotor activities) and video analysis (for collision actions). Neuromuscular fatigue was quantified using countermovement jump tests on force plates which were conducted ~ 24 to 48 hours pre- and post-match. Partial least squares correlation (PLSC) leave one variable out (LOVO) procedure established the relative variable contribution to both external load (X matrix) and neuromuscular fatigue (Y matrix) constructs. Linear mixed-effects models were then constructed to determine the variance explained by the latent scores applied to the variables representing these constructs. For external load, both locomotor and collision variables were identified for the forwards and the backs, although the identified variables differed between groups. For neuromuscular fatigue, jump height was identified as a high contributor for the forwards and the backs, with concentric impulse and reactive strength index high contributors only for the backs. The explained variance between the external load and neuromuscular fatigue latent constructs at the individual player level was 4.4% and 32.2% in the forwards and the backs models, respectively. This discrepancy may be explained by differences in match-play external loads and/or the specificity of the tests to measure indicators of fatigue. These may differ due to, for example, the activities undertaken in the different positional groups.

Potential of Soft-Shelled Rugby Headgear to Lower Regional Brain Strain Metrics During Standard Drop Tests.

BACKGROUND: The growing concern for player safety in rugby has led to an increased focus on head impacts. Previous laboratory studies have shown that rugby headgear significantly reduces peak linear and rotational accelerations compared to no headgear. However, these metrics may have limited relevance in assessing the effectiveness of headgear in preventing strain-based brain injuries like concussions. This study used an instantaneous deep-learning brain injury model to quantify regional brain strain mitigation of rugby headgear during drop tests. Tests were conducted on flat and angled impact surfaces across different heights, using a Hybrid III headform and neck. RESULTS: Headgear presence generally reduced the peak rotational velocities, with some headgear outperforming others. However, the effect on peak regional brain strains was less consistent. Of the 5 headgear tested, only the newer models that use open cell foams at densities above 45 kg/m3 consistently reduced the peak strain in the cerebrum, corpus callosum, and brainstem. The 3 conventional headgear that use closed cell foams at or below 45 kg/m3 showed no consistent reduction in the peak strain in the cerebrum, corpus callosum, and brainstem. CONCLUSIONS: The presence of rugby headgear may be able to reduce the severity of head impact exposure during rugby. However, to understand how these findings relate to brain strain mitigation in the field, further investigation into the relationship between the impact conditions in this study and those encountered during actual gameplay is necessary.

Athlete Health Implications of Match Injuries in Portuguese Rugby Union.

OBJECTIVE: Our aim was to report time-loss match injuries in Portugal's "Divisão de Honra" (Portuguese first tier) in the 2022/2023 season, focusing on injury incidence, burden, anatomical region, and type, to assess their impact on athletes' health and availability to play. METHODS: A prospective cohort study was conducted monitoring injuries via an online form filled in by each team's medical department, categorizing player position, as well as injury type, location, and severity. Incidence and burden were calculated per 1000 player-match-hours. RESULTS: The overall injury incidence was 54.4 injuries per 1000 player-match-hours (95% CI 30.3-96.2). Forwards had higher injury incidence than backs. Lower limbs were the most affected locations-29 injuries/1000 h of exposure (95% CI 13.7-52.0). Sprain/ligaments injuries were the most common type of injury (14.4 injuries/1000 h (95% CI 3.7-30.0), followed by muscle injuries (8.1 injuries/1000 h 95% CI 4.9-11.5). DISCUSSION: Injury incidence was higher than what is reported in amateur competitions and lower than for professionals. Injury severity was similar to that in other studies. Our study suggests a lower injury burden than in other semi-professional and elite leagues. These findings highlight the need for targeted injury prevention strategies in the Portuguese Rugby Union to increase athletes' availability by decreasing injury incidence and/or burden. Further research with broader participation and training injury data is needed.

Magnetic resonance imaging of the shoulder in symptomatic professional rugby players: a retrospective analysis.

OBJECTIVE: Shoulder injuries in rugby players are common due to frequent high-impact collisions and tackles. This study aimed to describe the spectrum and pattern of shoulder MRI findings in professional rugby players. METHODS: Single-center retrospective study of shoulder MRI was carried out between 2012 and 2016 in symptomatic professional male rugby league and rugby union players. One hundred ten shoulder MRIs were scored for rotator cuff and long head of biceps tendons, labral, bursal, joint, and osseous abnormalities. MRI features were compared using the chi-square or Fisher's exact tests for categorical variables. RESULTS: There were a total of one hundred ten professional male rugby players (80 rugby league and 30 rugby union), with a mean age of 24.6 (range 17-38) and 23.7 (range 17-33) years old, respectively. Rotator cuff or long head biceps abnormality was found in 36 (33%) players, of which 22 (20%) were either partial or full-thickness tears. Glenoid labral tears were present in 63 (57%) players. There was no significant difference (p > 0.05) in the frequency of tears of the superior (24%), anterior inferior (25%), posterior superior (25%), and posterior inferior (32%) labrum. Forty-seven percent of players presented with two or more abnormalities of the rotator cuff tendons and glenoid labrum. There were significantly more osseous abnormalities in backs compared to forwards (48% vs. 21%; p = 0.01). CONCLUSIONS: There is a wide spectrum of shoulder abnormalities on MRI in professional rugby players, and many have two or more abnormalities. In common with other contact sports, posterior labral injury was a common finding and may relate to sub-clinical trauma, without an association with instability.

Hang up your cleats and hope for the best? A cross-sectional study of five health domains in retired elite female rugby players.

Objectives: To investigate retired elite female rugby players' health outcomes (and their relationships) in five key areas (musculoskeletal, cognitive, mental, reproductive/endocrinological and cardiovascular) and how those compare with the general population. Methods: Female rugby players aged ≥18 years old and retired from elite competition ≥2 years were recruited via email or social media to complete a 179-item online questionnaire and neurocognitive assessment. Data from general population controls (matched for age and sex) were obtained where available. Results: 159 participants responded (average age 43 (±5) years). 156 (98%) reported a hip/groin, knee, foot/ankle or lower back injury during their career, of which 104 (67%) reported ongoing pain. Participants reported worse hip and knee outcomes compared with the general population (p<0.0001). 146 (92%) reported sustaining one or more concussions. History of concussion was associated with lower-than-average scores on neurocognitive assessment. Compared with general population data, retired female rugby players reported less anxiety (OR=0.079 (95% CI 0.03 to 0.19)), depression (OR=0.67 (95% CI 0.57 to 0.78)) and distress (OR=0.17 (95% CI 0.15 to 0.19)). Amenorrhoea rates were higher compared with matched controls, and the age at menopause was younger. The prevalence of hypertension was higher. The rugby players perceived that their health decreased in retirement and cited a lack of physical activity as a main contributor. Conclusion: Our findings point to the potential value of screening and monitoring, and identifying preventative measures during sporting careers to promote health and long-term quality of life for athletes.

Contact load practices and perceptions in elite English rugby league: an evaluation to inform contact load guidelines.

Background: Athlete exposure to contact could be a risk factor for injury. Governing bodies should provide guidelines preventing overexposure to contact. Objectives: Describe the current contact load practices and perceptions of contact load requirements within men's and women's rugby league to allow the Rugby Football League (RFL) to develop contact load guidelines. Methods: Participants (n=450 players, n=46 coaching staff, n=32 performance staff, n=23 medical staff) completed an online survey of 27 items, assessing the current contact load practices and perceptions within four categories: "current contact load practices" (n=12 items), "perceptions of required contact load" (n = 6 items), "monitoring of contact load" (n=3 items), and "the relationship between contact load and recovery" (n=6 items). Results: During men's Super League pre-season, full contact and controlled contact training was typically undertaken for 15-30 minutes per week, and wrestling training for 15-45 minutes per week. During the in-season, these three training types were all typically undertaken for 15-30 mins per week. In women's Super League, all training modalities were undertaken for up to 30 minutes per week in the pre- and in-season periods. Both men's and women's Super League players and staff perceived 15-30 minutes of full contact training per week was enough to prepare players for the physical demands of rugby league, but a higher duration may be required to prepare for the technical contact demands. Conclusion: Men's and women's Super League clubs currently undertake more contact training during pre-season than in-season, which was planned by coaches and is deemed adequate to prepare players for the demands of rugby league. This study provides data to develop contact load guidelines to improve player welfare whilst not impacting performance.

Instrumented mouthguards in elite-level men's and women's rugby union: characterising tackle-based head acceleration events.

Objectives: To examine the propensity of tackle height and the number of tacklers that result in head acceleration events (HAEs) in elite-level male and female rugby tackles. Methods: Instrumented mouthguard data were collected from women (n=67) and men (n=72) elite-level rugby players from five elite and three international teams. Peak linear acceleration and peak angular acceleration were extracted from HAEs. Propensities for HAEs at a range of thresholds were calculated as the proportion of tackles/carries that resulted in an HAE exceeding a given magnitude for coded tackle height (low, medium, high) and number of tacklers. Propensity ratios with 95% CIs were calculated for tackle heights and number of tacklers. Results: High tackles had a 32.7 (95% CI=6.89 to 155.02) and 41.2 (95% CI=9.22 to 184.58) propensity ratio to cause ball carrier HAEs>30 g compared with medium tackles for men and women, respectively. Low tackles had a 2.6 (95% CI=1.91 to 3.42) and 5.3 (95% CI=3.28 to 8.53) propensity ratio to cause tackler HAEs>30 g compared with medium tackles for men and women, respectively. In men, multiple tacklers had a higher propensity ratio (6.1; 95% CI=3.71 to 9.93) than singular tacklers to cause ball carrier HAEs>30 g but a lower propensity ratio (0.4; 95% CI=0.29 to 0.56) to cause tackler HAEs>30 g. No significant differences were observed in female tacklers or carriers for singular or multiple tacklers. Conclusion: To limit HAE exposure, rule changes and coaching interventions that promote tacklers aiming for the torso (medium tackle) could be explored, along with changes to multiple tackler events in the male game.

Lateral extra-articular tenodesis at primary ACL reconstruction increases career length in professional rugby players.

PURPOSE: To assess the effect of preoperative and surgical factors on return to play (RTP) rates and career longevity of professional rugby athletes after primary anterior cruciate ligament (ACL) reconstruction (ACL-R). METHODS: A retrospective review of a consecutive cohort of professional rugby players undergoing primary ACL-R by the senior author between 2005 and 2019 was undertaken. Athletes were included if they were under contract with a professional rugby team at the time of injury and had a minimum of 2-year follow-up. Univariate and multivariate analyses were performed to determine significant predictors of RTP rate, time and career longevity. RESULTS: One hundred and eighteen rugby players with 125 ACL-Rs were identified. Return to professional rugby was achieved in 115/125 (92%) of cases at an average of 9.6 months and those athletes participated at the professional level for 5.9 ± 3.4 years after ACL-R. Younger age (p = 0.006) and ACL-R with a concomitant lateral extra-articular tenodesis (LET) (p = 0.013) were predictors of a longer career. A Cox proportional hazards model that controlled for age revealed that athletes who underwent ACL-R with an LET had increased career longevity compared to those with an ACL-R without LET (hazard ratio = 2.74, p = 0.021). No factors were significantly associated with RTP rate or RTP time. CONCLUSION: In professional rugby players undergoing primary ACL-R, those having ACL-R with a concomitant LET and younger age predicted increased career longevity. Rugby players who underwent LET at the time of ACL-R had an 18% greater chance of still playing professionally at 5 years compared to those who underwent ACL-R alone. LEVEL OF EVIDENCE: Level III.

High prevalence of harmful drinking habits and gambling among professional rugby players: mental health symptoms and lifestyle risks among New Zealand Super Rugby players-a cross-sectional survey.

Objectives: Determining the prevalence of mental health and lifestyle risk factors (smoking, alcohol consumption, recreational drug use, gambling, family violence and anger management) in New Zealand (NZ) male professional rugby players. Study design: Cross-sectional survey of mental health symptoms and lifestyle risk factors in male professional rugby players in NZ. Methods: Players from all five NZ men's Super Rugby Franchises were invited to complete an online questionnaire (SportCHAT) measuring demographic status and mental health symptoms. Descriptive and interferential statistical analyses were used to identify the most prevalent mental health and lifestyle risk factors. Results: 105 players participated in the study (response rate 52.5%). 51.4% of players were either at moderate or high risk for alcohol-related harm (defined as potential health, social, legal or financial problems linked to alcohol consumption). In comparison, 4.8% reported recreational drug use and 5% reported smoking tobacco. Twenty players (19%) reported engaging in gambling, with five of these reporting problematic gambling. 21% of players reported symptoms of depression, but none reached the 'mild depression' threshold of the Patient Health Questionnaire for Depression. Younger players (aged 20-29) were more likely to report symptoms of depression than older players (aged 30-39). The prevalence of anxiety symptoms was 17.1%. 66.7% of these players reported minimal symptoms (GAD-7 score 0-4) and 33.3% reported mild symptoms (GAD-7 score 5-9). Family violence was reported by 2.9% of respondents, while 12.4% reported issues with anger management. There were no significant differences between ethnic groups. Conclusion: There is a higher prevalence of alcohol misuse and gambling, but lower reported rates of depression and anxiety symptoms in this cohort when compared with the general population.

Changes in Physical Fitness, Muscle Damage and Cognitive Function in Elite Rugby Players over a Season.

This study proposes to monitor the physical, immune and cognitive responses and adaptations of elite rugby players throughout the season based on the loads performed. Anthropometric measurements, physical fitness tests (e.g., muscle strength and power, linear and change-of-direction speed, cardiorespiratory fitness) and analyses of serum concentrations of markers of muscle damage (creatine kinase [CK] and lactate dehydrogenase [LDH]) and brain-derived neurotrophic factor (BDNF) were carried out over a sporting season (24 weeks) for 17 elite rugby players (10 forwards and 7 backs) aged 18.91 ± 0.76 years. The physical fitness test results show improvements in the performance of both forwards and backs over the season (p < 0.05), with an advantage for backs compared with forwards in most tests (p < 0.05). Muscle damage markers decreased at the end of the season compared with the baseline levels for forwards (p < 0.05). CK levels were unchanged for the backs, but there were increased LDH concentrations at the end of the season compared with baseline (p < 0.05). Serum BDNF levels decreased for the total group between the second and third sampling (p < 0.05). The muscular and physical capacities of rugby players differ according to their playing position. Immune responses and adaptations, as well as BDNF levels, vary throughout the season and depend on the physical load performed.

Reliability, interrelationships, and minimal detectable changes of strength and power metrics among well-trained rugby sevens players.

Despite the importance of strength and power in rugby skills and match outcomes, there exists a noticeable gap in the measurement consistency and estimation of a true change of typical assessments designed to assess these qualities. To address this gap, we investigated the between-session reliability, interrelationships, and minimal detectable changes (MDC) of commonly used strength and power measures in team sports. Sixteen national-level rugby 7 s players were tested on two occasions, one week apart. Both the best and average (of 2-3 trials) peak force, peak power, height, distance, and/or strength indices during countermovement jump (CMJ), drop jump (DJ), isometric mid-thigh pull (IMTP), plyometric push-up (PPU), and standing long jump (SLJ) were obtained. Furthermore, one-repetition maximum (1RM) strength for bench press and back squat, reactive strength index, and dynamic strength index were also determined. Reliability was assessed using intraclass correlation coefficients (ICC) and coefficients of variation (CV), and used for MDC calculations, and interrelationships between variables were determined using correlation coefficients. Reliability was excellent for bench press, back squat, and SLJ (ICCs > 0.91); high to excellent for IMTP peak force, all CMJ, and DJ (except best DJ height and contact time), and PPU peak force parameters (ICCs > 0.78), with < 10% CVs (except PPU peak power). MDCs were generally smaller for average than best values. Large to very large relationships (r = 0.60 to 0.85) were observed between bench press, back squat, and IMTP with selected parameters of CMJ and PPU (p < 0.05), but not in DJ and SLJ. In conclusion, selected measures of strength and power displayed high to excellent reproducibility, with average values (rather than best) offering more stable assessments, and "smaller" MDCs. Based upon the relationships, it can be inferred that maximising strength would likely contribute to enhanced explosive performance.

Protein and Leucine Requirements for Maximal Muscular Development and Athletic Performance Are Achieved with Completely Plant-Based Diets Modeled to Meet Energy Needs in Adult Male Rugby Players.

Rugby athletes consume large amounts of animal protein in accordance with conventional dietary guidance to increase muscle mass and strength. This misaligns with national dietary guidelines, which suggest limiting meat consumption for chronic disease prevention. The ability of completely plant-based diets to satisfy the nutritional needs of rugby players has not been explored. This study scaled nutrient data from a large population consuming completely plant-based diets with limited supplemental protein to meet the calorie requirements of adult male rugby athletes to assess whether protein and leucine recommendations for muscular development and athletic performance would be achieved. Calorie requirements were estimated from research that employed the doubly labeled water method, and dietary data from the Adventist Health Study-2 were scaled to this level. The modeled protein level was 1.68 g/kg/day, which meets recommendations for maximal gains in muscle mass, strength, and athletic performance. The modeled leucine level was 2.9 g/meal for four daily meals, which exceeds the threshold proposed to maximally stimulate muscle protein synthesis in young men. These results indicate that consuming large portions of completely plant-based meals can satisfy protein and leucine requirements for maximal muscular development and athletic performance in adult male rugby athletes while aligning with public health recommendations.

Player Activity and Load Profiling with Hidden Markov Models: A Novel Application in Rugby League.

Player movement in rugby league is complex, being spatiotemporal and multifaceted. Modeling this complexity to provide robust measures of player activity and load has proved difficult, with important aspects of player movement yet to be considered. These include the influence of time-varying covariates on player activity and the combination of different dimensions of player movement. Few studies have simultaneously categorized player activity into different activity states and investigated factors influencing the transition between states, or compared player activity and load profiles between matches and training. This study applied hidden Markov models (HMMs)-a data-driven, multivariate approach-to rugby league training and match GPS data to i) demonstrate how HMMs can combine multiple variables in a data-driven way to effectively categorize player movement states, ii) investigate the influence of two time-varying covariates, score difference and elapsed match time on player activity states, and iii) compare player activity and load profiles within and between training and match modalities. HMMs were fitted to player GPS, accelerometer and heart rate data of one English Super League team across 60 training sessions and 35 matches. Distinct activity states were detected for both matches and training, with transitions between states in matches influenced by score difference and elapsed time and clear differences in activity and load profiles between training and matches. HMMs can model the complexity of player movement to effectively profile player activity and load in rugby league and have the potential to facilitate new research across several sports.

We successfully derived player activity and load profiles in both training and match contexts in a data-driven and multivariate way using hidden Markov models.HMMs can be used to investigate the probability of changing between activity states as a function of time-varying covariates, augmenting current activity profiling practice.We discovered key differences between the activity and load profiles between training and matches in rugby league. In particular, a very directed high-speed running state in training that is seldom accessed by players in matches.We demonstrated how visualizing the output of HMMs can provide decision support by facilitating comparisons of activity and load profiles within and between players in matches and training.We posit that the methodology detailed in this paper can become a standardized approach to player activity and load profiling based on player movement data across multiple sports because it is flexible, data-driven, multivariate and statistically robust.

Are we tackle ready? Cross-sectional video analysis of match tackle characteristics in elite women's Rugby Union.

The tackle contest is the most common and most injurious match contact event in rugby and is an indicator of performance. Tackle Ready is World Rugby's tackle technique education program. Limited research has characterized the tackle contest in women's rugby. The purpose of this study is to: (1) identify the match situational characteristics, ball-carrier and tackler technical actions demonstrated in elite women's Rugby Union and (2) to determine the extent to which Tackle Ready recommended tackle techniques were exhibited. Technical characteristics for 1500 tackle events in the 2022-2023 Women's Six Nations Championship were visually assessed according to a predefined coding framework and the Tackle Ready program. Tackles lacked full completion (0.2%) of the 22 coded Tackle Ready techniques with 47% of the recommended techniques demonstrated in each tackle on average (range 15%-98%). A high proportion of tackles involved two defenders (48%), approaching ball-carriers from the side (38%) or oblique angles (39%), in an upright position (30%), and with initial contact made with the arm (51%). Incorrect pre-contact head positioning and head placement upon contact accounted for 50% and 15% of tackles, respectively, and there was a mean of 14 (95% CI 11-18) head and neck contacts to a tackler and 18 (95% CI 14-22) head and neck contacts to a ball-carrier per game. Targeted interventions to encourage adoption of recommended techniques are needed to reduce tackle-related injury risk in women's rugby. This study provides valuable context for future discussion across law enforcement, coach education and gender-specific tackle coaching in the women's game.