Rugby Sevens Research Articles

An Ice Vest Limits the Rise in Core Temperature During a Rugby Sevens Warm-up

An Ice Vest Limits the Rise in Core Temperature During a Rugby Sevens Warm-up

Differences in Change of Direction Speed and Deficit Between Male and Female National Rugby Sevens Players.

Freitas, TT, Alcaraz, PE, Calleja-González, J, Arruda, AFS, Guerriero, A, Kobal, R, Reis, VP, Pereira, LA, and Loturco, I. Differences in change of direction speed and deficit between male and female national rugby sevens players. J Strength Cond Res 35(11): 3170-3176, 2021-The aims of this study were to assess the change of direction (COD) deficit in different tasks and to investigate the differences in COD ability and COD deficit between male and female rugby sevens players. Thirty-six elite rugby players from the Brazilian National senior sevens teams (18 males and 18 females) completed the following physical assessments: squat and countermovement jumps; drop jump from a 45-cm height; horizontal single and triple jumps; 40-m linear sprint; Pro-agility, L-drill, and Zig-zag COD tests; and 1 repetition maximum test in the squat exercise. The differences between male and female performances were determined using magnitude-based inferences, an independent t test, and effect sizes (ES). Pearson's product-moment correlations were performed to determine the relationships among the different COD velocities and COD deficits. Men demonstrated likely to almost certainly significantly higher performances than women in all speed-power assessments and COD tasks (ES ranging from 0.61 to 2.09; p < 0.05), with the exception of the Zig-zag drill (ES = 0.24; p > 0.05). Furthermore, males displayed significantly greater COD deficits in all tests and higher sprint momentum (ES ranging from 0.78 to 2.95; p < 0.05). Large significant relationships among COD velocities (r ranging from 0.71 to 0.88; p < 0.05) and almost perfect significant correlations among all COD deficits (r ranging from 0.90 to 0.95; p < 0.05) were obtained in both sexes. The present results indicate that male rugby players are less efficient at changing direction, relative to their maximum sprint velocity. In addition, the correlations between the different COD deficits and COD speeds suggest that elite rugby players demonstrate similar ability to change direction, independently of the angle of directional change. From a practical perspective, this implies that a more comprehensive training strategy including eccentric exercises, acceleration-deceleration drills, and directional change technique is warranted to improve the COD ability (and reduce the COD deficit) of faster and more powerful rugby sevens players.

Situational factors affecting rugby sevens match performance

ABSTRACTPurpose: To examine the independent influence of a range of situational factors on physical and technical match performance during international rugby sevens matches.Methods: Data was collected from 20 professional rugby sevens players from one team across one competitive season. Activity profiles were measured using wearable microtechnology devices, and technical performance measures were collected using match video analysis. A principal components analysis was conducted to reduce the dimensionality of the physical and technical match performance variables into single index values incorporating each variable’s distinct information. Linear mixed models were then constructed to examine the collective influence of external contextual factors on physical and technical index scores.Results: Increased points conceded, a winning match outcome, and more favourable weather all had positive impacts on the Physical Performance Factor, with all other situational factors examined not contributing to a significantly better model fit. Technical Performance Factor values were shown to increase with longer match involvement durations and decrease when playing against higher ranked opponents.Conclusions: These findings show that winning the match, conceding more points, and more favourable weather conditions are associated with increased physical performance; whilst technical performance improved with longer playing durations and playing lower ranked opponents.

Individual Factors Affecting Rugby Sevens Match Performance.

Purpose: To examine the collective independent influence of a range of individual characteristics on physical and technical match performance during international rugby sevens matches. Methods: Data were collected from 20 international rugby sevens players from 1 team across 1 season. Activity profiles were measured using wearable microtechnology devices, and technical performance measures were collected from match video analysis. Subjective well-being measures were collected using a well-being questionnaire completed on the morning of main training days, and groin-squeeze assessments at 0° and 60° knee flexion were also conducted using a sphygmomanometer. Assessments of aerobic fitness were completed periodically across the season, including time to complete a 2-km run and final velocity during the 30:15 Intermittent Fitness Test (VIFT). A principal-components analysis was conducted to reduce the dimensionality of the physical and technical variables into single-factor values. Linear mixed models were then constructed to examine the collective influence of a range of individual contextual variables on physical and technical performance factors. Results: Increased muscle soreness, stress, and VIFT were associated with trivial to small increases in physical and technical performance values, whereas trivial to small decreases were associated with higher perceived recovery, body weight, and groin squeeze (0° knee flexion). Conclusions: A range of well-being metrics are required to account for a significant portion of the variance in physical and technical performance. These factors may be manipulated by coaches or practitioners to achieve favorable physiological readiness that may lead to improved match performance.

Subjective and Objective Responses to Two Rugby Sevens World Series Competitions.

Fowler, PM, Murray, A, Farooq, A, Lumley, N, and Taylor, L. Subjective and objective responses to two rugby sevens world series competitions. J Strength Cond Res 33(4): 1043-1055, 2019-The purpose was to examine the utility of subjective and objective measures of player preparedness, interpreted at both group level and individual level, during 2 consecutive competitions of the World Rugby Sevens Series (WRSS). Subjective (sleep, energy, and muscle soreness ratings) and objective (heart rate [HR] at rest [HRREST] and in response to submaximal exercise [HREX]) measures were obtained from 16 male rugby 7s players from 1 team for 3 consecutive days (D1-3) at home (HOME) and on arrival at 4 tournament (T1-4) locations (T1-New Zealand; T2-USA; T3-Hong Kong; and T4-Tokyo) across 2 WRSS competitions (2 tournaments per competition) separated by 1 month. At a group level, energy ratings were significantly lower in T2 and T4 compared with HOME, and on D1 T2 compared with D1 T1 (p ≤ 0.05). Greatest variability in subjective ratings was observed during T1 and T3 at an individual level, particularly for sleep quality. Although at a group level HRREST and HREX significantly decreased in T1-4 compared with HOME (p ≤ 0.05), there was only a ∼50% agreement between the direction of change in HR indices at an individual level. Results from this study suggest that relocation between tournaments within WRSS competitions disrupts player preparedness measures to the largest degree. Hence, this period could be targeted by practitioners with appropriate recovery and/or sleep-promoting interventions or modulation of match-/training-load. Moreover, subjective rather than objective measures seem to be of greater use to inform player preparedness decision making, particularly at an individual level compared with a group level.

Psychological Demands of International Rugby Sevens and Well-Being Needs of Elite South African Players.

Rugby sevens was included in the 2016 Olympic Games, with South Africa’s Blitzboks winning bronze. They also won the 2016/2017 and 2017/2018 World Rugby Sevens Series. Whilst peak performance is paramount at the elite level there is a growing responsibility to address player well-being and off-the-field player needs. This study explored the psychological demands of international rugby sevens and the well-being needs of elite players. Twenty professional players (age range: 21–33 years) participated in semi-structured interviews. Qualitative content analysis yielded five categories of psychological demands: (1) tournament structure, (2) resilience, (3) cope with physicality, (4) perform when fatigued, and (5) perform under pressure. The prevailing team culture included: (1) team cohesion, (2) clear purpose, (3) work ethic, (4) team values, (5) happy environment, (6) relationships with coaching staff, and (7) faith. Various psychological skills [(1) goal-directed behavior, (2) compartmentalization, (3) deal with anxiety, (4) motivation, (5) imagery, and (6) self-confidence] and mental strategies [(1) coping, (2) “back-to-zero,” (3) creativity, and (4) cognitive triggers] utilized by the players are discussed. Their general well-being and individual needs were: (1) physical needs, (2) financial concerns/needs, (3) preparation for life after rugby career, (4) support structures, and (5) mental (ill) health. This information could be useful to develop an integrated sport psychological and well-being program aimed at improving performance and facilitating psychological well-being both during and after retirement from elite sport.

A 2-Year Prospective Study of Injury Epidemiology in Elite Australian Rugby Sevens: Exploration of Incidence Rates, Severity, Injury Type, and Subsequent Injury in Men and Women

Background: Injuries are common in rugby sevens, but studies to date have been limited to short, noncontinuous periods and reporting of match injuries only. Purpose: To report the injury incidence rate (IIR), severity, and burden of injuries sustained by men and women in the Australian rugby sevens program and to provide the first longitudinal investigation of subsequent injury occurrence in rugby sevens looking beyond tournament injuries only. Study Design: Descriptive epidemiology study. Methods: Ninety international rugby sevens players (55 men and 35 women) were prospectively followed over 2 consecutive seasons (2015-2016 and 2016-2017). All medical attention injuries were reported irrespective of time loss. Individual exposure in terms of minutes, distance, and high-speed distance was captured for each player for matches and on-field training, with the use of global positioning system devices. The IIR and injury burden (IIR × days lost to injury) were calculated per 1000 player-hours, and descriptive analyses were performed. Results: Seventy-three players (81.1%) sustained 365 injuries at an IIR of 43.2 per 1000 player-hours (95% CI, 38.8-47.8). As compared with male players, female players experienced a lower but nonsignificant IIR (incidence rate ratio, 0.91; 95% CI, 0.73-1.12). Female players also sustained a higher proportion of injuries to the trunk region (relative risk, 1.75; 95% CI, 1.28-2.40) but a lower number to the head/neck region (relative risk, 0.58; 95% CI, 0.37-0.93; P = .011). The majority (80.7%) of subsequent injuries were of a different site and nature than previous injuries. A trend toward a reduced number of days, participation time, distance, and high-speed distance completed before the next injury was observed after successive injury occurrence. Conclusion: A trend for a lower IIR was observed for female players compared with male players, with variation of injury profiles observed between sexes. With a surveillance period of 2 years, subsequent injuries account for the majority of injuries sustained in rugby sevens, and they are typically different from previous types of sustained injuries. After each successive injury, the risk profile for future injury occurrence appears to be altered, which warrants further investigation to inform injury prevention strategies in rugby sevens.

High Match Load's Relation to Decreased Well-Being During an Elite Women's Rugby Sevens Tournament.

To determine changes in well-being, recovery, and neuromuscular performance during and after an elite women's rugby sevens tournament and assess the influence of match-load indicators. Twelve elite women rugby sevens players (age = 25.3 [4.1]y, height = 169.0 [4.0]cm, weight = 63.9 [4.9]kg, and body fat = 18.6% [2.7%]) performed 5 matches during a 2-d tournament of the Women's Rugby Sevens World Series. Perceived well-being (fatigue, sleep quality, general muscle soreness, stress levels, and mood), total quality of recovery, and countermovement-jump flight time were measured on match days 1 and 2, 1 d posttournament, and 2 d posttournament. Total distance; low-, moderate-, and high-intensity running; and physical contacts during matches were derived from global positioning system-based time-motion analysis and video-based notational analysis, respectively. Internal match load was calculated by session rating of perceived exertion and playing time (rating of perceived exertion × duration). Well-being (P < .001), fatigue (P < .001), general muscle soreness (P < .001), stress levels (P < .001), mood (P = .005), and total quality of recovery (P < .001) were significantly impaired after match day 1 and did not return to baseline values until 2 d posttournament. More high-intensity running was related to more fatigue (r = -.60, P = .049) and a larger number of physical contacts with more general muscle soreness (r = -.69, P = .013). Perceived well-being and total quality of recovery were already impaired after match day 1, although performance was maintained. High-intensity running and physical contacts were predominantly related to fatigue and general muscle soreness, respectively.

Repeated High-Intensity Effort Activity in International Male Rugby Sevens.

Couderc, A, Gabbett, TJ, Piscione, J, Robineau, J, Peeters, A, Igarza, G, Thomas, C, Hanon, C, and Lacome, M. Repeated high-intensity effort activity in international male Rugby Sevens. J Strength Cond Res 35(6): 1720-1726, 2023-Rugby Sevens is characterized by repeated high-intensity accelerations, sprinting, and collisions, commonly referred to as repeated high-intensity effort (RHIE) activity. Although repeated acceleration and sprinting activity of Rugby Sevens has been investigated, to date, no study has investigated the repeated running and collision activity of international Rugby Sevens during competitive events. In this study, 15 elite players competed in 44 matches during the HSBC World Sevens Series. Global positioning systems and match analysis software were used to quantify the frequency of repeated running and collision efforts. High acceleration (≥2.5 m·s -2 ), high speed (above maximal aerobic speed), sprint (above 85% of maximal sprint speed), and collision efforts (tackles, ruck, and contact) were considered as high-intensity effort activities. An RHIE bout was defined as 3 or more high-intensity efforts with less than 21 seconds recovery between efforts. The difference between positional groups (forward and backs) and first and second halves was compared using magnitude-based inferential statistics. One hundred twelve individual match observations were analyzed. On average, players performed 27 high-intensity effort events across the game. The distribution of high-intensity efforts included the following: 37% collisions, 34% accelerations, 27.5% high-velocity running, and 1.5% sprints. An average of 3.7 RHIE bouts was performed per player. The difference in high-intensity efforts and number of RHIE bouts performed were trivial/small when compared between first and second halves, and between forward and back positional groups. Repeated high-intensity effort bouts play an important role in the activity profile of elite Rugby Sevens players. This study could provide a framework for performance analysts and coaches to analyze match-related performance of elite Rugby Sevens players, taking into account both the high-intensity running and collision components of the game. Coaches should implement training interventions to ensure the maintenance of RHIE performance during competitive events.

Validity of a Microsensor-Based Algorithm for Detecting Scrum Events in Rugby Union.

Commercially available microtechnology devices containing accelerometers, gyroscopes, magnetometers, and global positioning technology have been widely used to quantify the demands of rugby union. This study investigated whether data derived from wearable microsensors can be used to develop an algorithm that automatically detects scrum events in rugby union training and match play. Data were collected from 30 elite rugby players wearing a Catapult OptimEye S5 (Catapult Sports, Melbourne, Australia) microtechnology device during a series of competitive matches (n = 46) and training sessions (n = 51). A total of 97 files were required to "train" an algorithm to automatically detect scrum events using random forest machine learning. A further 310 files from training (n = 167) and match-play (n = 143) sessions were used to validate the algorithm's performance. Across all positions (front row, second row, and back row), the algorithm demonstrated good sensitivity (91%) and specificity (91%) for training and match-play events when the confidence level of the random forest was set to 50%. Generally, the algorithm had better accuracy for match-play events (93.6%) than for training events (87.6%). The scrum algorithm was able to accurately detect scrum events for front-row, second-row, and back-row positions. However, for optimal results, practitioners are advised to use the recommended confidence level for each position to limit false positives. Scrum algorithm detection was better with scrums involving ≥5 players and is therefore unlikely to be suitable for scrums involving 3 players (eg, rugby sevens). Additional contact- and collision-detection algorithms are required to fully quantify rugby union demands.

Training Periodization Over an Elite Rugby Sevens Season: From Theory to Practice.

To describe the training periodization in rugby sevens players competing in the World Rugby Sevens Series during a non-Olympic season. Workload data were collected over a 33-wk period in 12 male players participating in a full competitive season. Workload was quantified using session rating of perceived exertion and global positioning system-derived data during training and competition. Self-reported well-being was assessed using a questionnaire. Each variable was analyzed weekly and through 5 mesocycles (preseason, in-season 1-4), each of which ended with competition blocks. The perceived load decreased throughout the season for the full squad (-68% [26%] between preseason and final competitive block, large effect) and when unavailable players were removed from the analysis (-38% [42%], moderate). Weekly perceived load was highly variable, with a typical periodization in 4 phases during each mesocycle (regeneration, training overload, taper, and competition). During the preseason, the workload was higher during the overload training phase than during the competitive period (range: +23% to +59%, large to very large, for the distance covered above individual maximal aerobic speed and the number of accelerations). This observation no longer persisted during the season. The well-being score decreased almost certainly from in-season 3 (moderate). These results highlighted the apparent difficulty in maintaining high-load training periods throughout the season in players engaged on the World Rugby Sevens Series despite ∼4-7 training weeks separating each competitive block. This observation was likely explained by the difficulties inherent to the World Rugby Sevens Series (risk of contact injury, calendar, and multiple long-haul travel episodes) and potentially by limited squad-rotation policies.

Movement Patterns and Muscle Damage During Simulated Rugby Sevens Matches in National Team Players.

Pereira, LA, Nakamura, FY, Moraes, JE, Kitamura, K, Ramos, SP, and Loturco, I. Movement patterns and muscle damage during simulated rugby sevens matches in national team players. J Strength Cond Res 32(12): 3465-3474, 2018-The aim of this study was to analyze the match performance (i.e., distance covered in different intensities), signs of muscle damage (assessed by means of creatine kinase [CK] activity and rate of force development [RFD]), and neuromuscular fatigue (using linear sprint and vertical jump performances) after 3 single-day simulated matches performed by rugby sevens players from the Brazilian National team. Ten male rugby sevens players (25.2 ± 3.6 years; 88.7 ± 7.1 kg; 182.2 ± 6.3 cm) participated in this study. On the day before the matches, the athletes performed a 40-m sprint, a vertical jump assessment, and a maximal isometric force test. In the morning of the match day, blood samples were collected to analyze the CK activity. Afterward, 3 simulated rugby sevens' matches were performed with 2-hour intermission periods. The match performance (encompassing total distance and distance covered in different velocity ranges and body loads [BLs]) was obtained from global positioning system units. The statistical analysis was performed using a mixed model approach and the effect sizes (ESs) of the differences. The statistical significance level was set at p ≤ 0.05. Players were capable of maintaining the match performance when comparing the first and last games. Large (ES > 0.8) and significant (p ≤ 0.05) reductions were demonstrated in the total distance and BL when comparing the second with the first halves. Decrements in the explosive force capacity (assessed by means of RFD) and the squat jump (SJ) were noticed (ES varying from 0.55 to 1.14; p ≤ 0.05). The CK activity increased after the matches (ES = 1.29; p ≤ 0.05). The rugby sevens players were able to maintain the physical performance across 3 successive matches simulating the first day of a tournament. The augmented CK activity and the decreases in the SJ and RFD suggest that increased levels of muscle damage were experienced on the day after the matches. Therefore, the technical staff are encouraged to implement recovery strategies and planned substitutions during multiday tournaments to reduce the impact of accumulated fatigue and muscle damage on subsequent match performance. In addition, specific training strategies aimed at better simulating the match demands need to be implemented in the players' training routines.

Stress and coping in Fijian rakavi (rugby) sevens players

Little is known about stress and coping among professional rugby players from the Pacific. Guided by phenomenological research orientation, this study aimed to identify sources of stress and coping strategies using semi-structured interviews with a sample of 12 male Fijian professional rugby players. Findings of the template analysis indicate that organizational stressors and environmental issues were dominant but differed in nature between the training camp and competition settings. Players experienced more uncontrollable situations than controllable ones in both settings and thus made greater use of emotion-focused coping strategies as a means to reduce stress. Disengagement and ‘working off the energy’ were the most frequently cited coping strategies. ‘Silently the Fijian way’ was identified by the players as a culturally specific form of coping. The findings of this study provide a foundation for future research into stress and coping in the context of professional rugby in Fiji and other Pacific Islands.

Can we use GPS for assessing sprinting performance in rugby sevens? A concurrent validity and between-device reliability study.

The purpose of this study was to (1) provide data on maximal sprinting speed (MSS) and maximal acceleration (Amax) in elite rugby sevens players measured with GPS devices, (2) test the concurrent validity of the signal derived from a radar device and a commercially available 16 Hz GPS device, and (2) assess the between-device reliability of MSS and Amax of the same GPS. Fifteen elite rugby sevens players (90 ± 12 kg; 181 ± 8 cm; 26 ± 5 y) participated in the maximal sprinting test. A subset of five players participated in the concurrent validity and between-devices reliability study. A concurrent validity protocol compared the GPS units and a radar device (Stalker ATS II). The between-device reliability of the GPS signal during maximal sprint running was also assessed using 6 V2 GPS units (Sensorevery-where, Digital Simulation, Paris, France) attached to a custom-made steel sled and pushed by the five athletes who performed a combined total of 15 linear 40m sprints. CV ranged from 0.5, ±0.1 % for MSS and smoothed MSS to 6.4, ±1.1 % for Amax. TEM was trivial for MSS and smoothed MSS (0.09, ±0.01) and small for Amax and smoothed Amax (0.54, ±0.09 and 0.39, ±0.06 respectively). Mean bias ranged from -1.6, ±1.0 % to -3.0, ±1.1 % for smoothed MSS and MSS respectively. TEE were small (2.0, ±0.55 to 1.6, ±0.4 %, for MSS and smoothed MSS respectively. The main results indicate that the GPS units were highly reliable for assessing MSS and provided acceptable signal to noise ratio for measuring Amax, especially when a smoothing 0.5-s moving average is used. This 16 Hz GPS device provides sport scientists and coaches with an accurate and reliable means to monitor running performance in elite rugby sevens.

Alterations in core temperature during World Rugby Sevens Series tournaments in temperate and warm environments

Purpose: To characterize player core temperature (Tc) across two separate World Rugby Sevens Series (WRSS) tournaments in temperate and warm environments. Methods: Tc was collected in seventeen playing members of one men’s team competing at the Singapore (n = 12) and London (n = 11) WRSS tournaments. Exertional heat illness (EHI) symptoms, cooling strategy use, playing minutes and wet blub globe temperature (WBGT) were also collected. Linear mixed models and magnitude-based inferences assessed differences in Tc between all periods within-and between tournaments and were also used to assess the effect of WBGT and playing minutes on Tc. Results: Several players experienced Tc in excess of 38°C during warm-ups and 39°C during games. The highest mean Tc values were observed in the final game on all days and in Singapore Day Two, there were substantial game-on-game increases in mean Tc. These Tc responses were associated with playing minutes (effect size; ±90% CL = 0.38; ±0.20), although the effect of WBGT was trivial and unclear. Further, there were no differences in Tc between the two tournaments in the different environments. Despite high individual peak Tc values (Singapore 39.9°C; London 39.6°C); no signs/symptoms of EHI were reported, voluntary post-game cooling usage was minimal, and pre- and mid-cooling strategies were not implemented. Conclusions: During WRSS matches, peak Tc values approached thresholds associated with EHI (>40°C) and exceeded those demonstrated to reduce repeated sprint performance (>39°C). Practitioners may consider the use of compatible cooling and heat acclimation strategies to minimize Tc increase and maximize player preparedness and recovery.

Risk factors of contact injuries among U.S. women Rugby sevens

Risk factors of contact injuries among U.S. women Rugby sevens

One-Repetition-Maximum Measures or Maximum Bar-Power Output: Which Is More Related to Sport Performance?

To compare the associations between optimum power loads and 1-repetition-maximum (1RM) values (assessed in half-squat and jump-squat exercises) and multiple performance measures in elite athletes. Sixty-one elite athletes (15 Olympians) from 4 different sports (track and field [sprinters and jumpers], rugby sevens, bobsled, and soccer) performed squat and countermovement jumps, half-squat exercise (to assess 1RM), half-squat and jump-squat exercises (to assess bar-power output), and sprint tests (60m for sprinters and jumpers and 40m for the other athletes). Pearson product-moment correlation test was used to determine relationships between 1RM and bar-power outputs with vertical jumps and sprint times in both exercises. Overall, both measurements were moderately to near perfectly related to speed performance (r values varying from -.35 to -.69 for correlations between 1RM and sprint times, and from -.36 to -.91 for correlations between bar-power outputs and sprint times; P < .05). However, on average, the magnitude of these correlations was stronger for power-related variables, and only the bar-power outputs were significantly related to vertical jump height. The bar-power outputs were more strongly associated with sprint-speed and power performance than the 1RM measures. Therefore, coaches and researchers can use the bar-power approach for athlete testing and monitoring. Due to the strong correlations presented, it is possible to infer that meaningful variations in bar-power production may also represent substantial changes in actual sport performance.

Medical Attention Injury Rates in U.S. Women Rugby-7s Players by Positions

PURPOSE: There is a lack of injury data on women’s rugby, and less on the Olympic format of Rugby-7s. Reporting medical-attention injuries may provide a more complete picture of the true burden of injury and illness in sport. The aim was to determine medical attention (no time-loss) injury incidence in U.S. women’s Rugby-7s. METHODS: A prospective epidemiology study of U.S. women Rugby-7s (6,768 players; 564 teams), in multi-level USA Rugby and USA Sevens LLC tournaments (2010-2014). Incidence (per 1000 player-hour (ph)) and biomechanism of medical attention injuries were captured via the Rugby Injury Survey & Evaluation (RISE) Report methodology. RESULTS: Medical attention injury rate was found at 84.4/1000 ph (n=356). Amongst positions, injuries were found at similar rates (backs: 60%, 59.3/1000ph, n=143; forwards: 40%, 53.6/1000ph, n=97; RR=1.11; P=0.447). Most injuries were acute (95%) occurring during the tackle (67%). Most match injuries were from a shoulder tackle (70%) (backs 72%; forwards 62%; RR=1.32; P=0.113). Recurrent injuries occurred at 25%. Lower extremity ligament sprains (53%) were most common, among injury types, muscle/tendon injuries were most common overall at 41% (backs 41/1000ph; forwards 42/1000ph; P=0.998). Knee injuries occurred more frequently in forwards (23%) than backs (16%; P<0.213). Head/neck injury rates, were 22% of all injuries. The sub-acute head contusion rate, where players were physician-cleared to return to sport was 6% (3.5/1000ph). CONCLUSIONS: Documentation of medical-attention incidents is recommended in the literature, as this is likely to capture a far greater number of ailments, than time loss injuries alone and will therefore, provide a more inclusive picture of the true burden of injury and illness in a population. A panoptic view of rugby-7s injury rates, provides fundamental gender injury data, to guide injury prevention protocols by stakeholders to guide player welfare. Head/neck and upper extremity injury rates (both at 21%) support an emphasis on tackling techniques for injury reduction. A program, including contact-based-awareness, for women newly introduced to this collision-sport, would nurture injury prevention. Furthermore, adherence on return to play protocols would decrease recurrent injury rates seen in this gender-specific cohort.

Erratum: Schuster (2018)

In Schuster J, Howells D, Robineau J, et al, “Physical-preparation recommendations for elite rugby sevens performance,” Int J Sports Physiol Perform. 2018;13(3):255–267, https://doi.org/10.1123/ijspp.2016-0728, an error was introduced that changed the meaning of the first sentence of the abstract. The word over was changed to more than. The sentence should read “Rugby sevens, a sport new to the Olympics, features high-intensity intermittent running and contact efforts over short match durations, normally 6 times across 2 to 3 d in a tournament format.” The online version of this article has been corrected.

Relationship between skeletal muscle contractile properties and power production capacity in female Olympic rugby players

This study aimed to determine which contractile properties measured by tensiomyography (TMG) could better differentiate athletes with high- and low-power values, as well as to analyse the relationship between contractile properties and power production capacity. The contractile properties of the vastus medialis (VM), rectus femoris (RF) and vastus lateralis (VL) of an Olympic women’s Rugby Sevens team (n = 14) were analysed before a Wingate test in which their peak power output (PPO) was determined. Athletes were then divided into a high-power (HP) and a low-power (LP) group. HP presented an almost certainly higher PPO (9.8 ± 0.3 vs. 8.9 ± 0.4 W kg−1, ES = 3.00) than LP, as well as a very likely lower radial displacement (3.39 ± 1.16 vs. 5.65 ± 1.50 mm, ES = 1.68) and velocity of deformation (0.08 ± 0.02 vs. 0.13 ± 0.03 mm ms−1, ES = 1.87) of the VL. A likely lower time of delay was observed in HP for all analysed muscles (ES > 0.60). PPO was very largely related to the radial displacement (r = −0.75, 90% CI = −0.90 to −0.44) and velocity of deformation (r = −0.70, 90% CI = −0.87 to −0.34) of the VL. A large correlation was found between PPO and the time of delay of the VL (r = −0.61, 90% CI = −0.84 to −0.22). No correlations were found for the contractile properties of RF or VM. These results highlight the importance of VL contractile properties (but not so much those of RF and VM) for maximal power production and suggest TMG as a practical technique for its evaluation.