Seasonal Variation and Positional Differences in Anthropometry, Strength, and Power Characteristics in English Premiership Women's Rugby Union Players.

ABSTRACT: Yao, X, Austerberry, A, Bishop, C, Wilson, L, Chiang, C-Y, and Turner, A. Seasonal variation and positional differences in anthropometry, strength, and power characteristics in English premiership women's rugby union players. J Strength Cond Res 38(5): 924-931, 2024-Women's rugby is a collision sport that relies heavily on body composition and physical characteristics of strength and power to achieve competitive success. Furthermore, the seasonal nature presents a variety of physical challenges that can cause fluctuations in a player's physical development. Therefore, the purpose of this study was to determine the differences in anthropometry, strength, and power characteristics between forwards and backs in women's rugby union athletes in England and to identify changes throughout a season. Forty-seven players were recruited from the English premiership women's rugby during the 2020-2021 season. Players were split into forwards and backs and underwent body composition testing by dual-energy X-ray absorptiometry and strength and power tests (countermovement jump, drop jump [DJ], and isometric midthigh pull) on 3 separate occasions (preseason, midseason, postseason). Overall, forwards had significantly ( p < 0.01) higher body mass, fat mass, lean mass [LM], bone mineral content, and take off momentum, and backs had significantly higher ( p < 0.01, d > 0.5) jump height, reactive strength, and shorter DJ contact time. When observing seasonal changes, there were statistically significant differences ( p < 0.01) or moderate-to-large practical differences ( d > 0.5) in LM, reactive strength index modified, time to take-off, and DJ flight time [FT] among forwards when comparing 3 testing time frames. For backs, statistically significant differences ( p < 0.01) or moderate-to-large practical differences ( d > 0.5) were reported in LM and DJ FT throughout the season. In conclusion, the strength and power testing and characteristics shown in this study could support coaches and junior women's rugby athletes to have a basic understanding of English premiership physical standards.

Longitudinal Development of Physical Characteristics and Function in Japanese Junior Rugby Union Players.

PURPOSE: To longitudinally investigate the development of physical characteristics and function during 3 years of high school among Japanese junior rugby players and examine the differences in these parameters between the positions. METHODS: In 83 junior rugby players (forwards: n = 46, backs: n = 37) from one Japanese high school team who had participated in national high school competitions, anthropometric variables (height, body mass, fat and lean body mass, and body mass index), upper- and lower-body strength (eg, 1-repetition-maximum [1RM] bench press, isokinetic knee muscle strength at 60°/s and 180°/s), and sprint and jump performance were measured. Upper- and lower-body strength relative to body mass and lean body mass were also calculated. RESULTS: All anthropometric indices improved with increasing age, and the values were higher in forwards than in backs (all P < .05). The 1-repetition maximum bench press (forwards: 40.8%, backs: 52.5%) and isokinetic knee strength (eg, extension at 60°/s, forwards: 15.4%, backs: 10.0%) improved with age (from 16 to 18 y), and they were higher in forwards than in backs (all P < .05). Meanwhile, the 1RM bench press relative to lean body mass did not differ between the positions. Isokinetic knee muscle strength at 60°/s and 180°/s relative to lean body mass and sprint and jump performance did not improve with age. CONCLUSION: These results indicate that Japanese junior rugby players need to develop larger physiques and continuously increase their lower-body strength to improve sprint and jump performance.

Asociación entre variables de empuje Isométrico de media pierna (EIMP) con variables antropométricas y cualidades físicas en jugadores varones de Rugby Amateurs / Relationships between Isometric Mid-Thigh pull with anthropometric variables and physical qualities in Amateur Rugby players / Relações entre a puxada isométrica do meio da coxa com variáveis antropométricas e qualidades físicas em jogadores amadores de rugby

Objetivo: el objetivo de este estudio es describir el perfil de las variables del EIMP entre las dos posiciones de juego y determinar las posibles asociaciones con las características antropométricas y las cualidades físicas de un grupo de jugadores Rugby amateurs chilenos. Hipótesis: es por eso por lo que podemos plantear como hipótesis la existencia de asociaciones entre las variables de EIMP y las cualidades físicas de los jugadores de RU. Diseño metodológico: este estudio tiene un diseño de cohorte observacional, descriptivo y correlacional. Se investigó la asociación existente entre las variables de EIMP con las pruebas físicas y las variables antropométricas. Fueron evaluados treinta y dos jugadores de rugby varones de nivel amateurs chilenos (promedio ( DE, edad, 23,3 ( 5,4 años). Resultados: para la variable Masa Muscular se encontraron asociaciones grandes (r = 0.53) (p = 0.001) con la FM y asociaciones moderadas (r = 0,48) (r = 0,47) (r = 0,44) (r = 0,46) con F50, F100, F150 y F200 respectivamente. También se pueden observar las asociaciones grandes (R2 = 0,305) (R2 = 0,297) (R2 = 0,267) entre 1RM PB y F200, F100 y F150, respectivamente. Conclusión: en conclusión, este estudio puede demostrar la existencia de asociaciones estadísticamente significativas entre algunas de las variables antropométricas y físicos con las variables de Fuerza de EIMP en jugadores de RU amateurs chilenos.

OBJECTIVE: The objective of this study is to describe the profile of the EIMP variables between two playing positions and to determine its possible associations with anthropometric characteristics and physical qualities of a group of Chilean amateur rugby players. HYPOTHESIS: There are associations between the EIMP variables and the physical qualities of UR players. METHODOLOGICAL DESIGN: This study has an observational, descriptive and correlational cohort design. The association between the EIMP variables, from the physical tests, and the anthropometric variables was investigated. Thirty-two Chilean amateur-level male rugby players were evaluated (mean ( SD, age, 23.3 ( 5.4 years). RESULTS: For the Muscle Mass variable, large associations were found (r=0.53) (p=0.001) to FM, and moderate associations (r=0.48) (r=0.47) (r=0.44) (r =0.46) to F50, F100, F150, and F200 respectively. Large associations (R2=0.305) (R2=0.297) (R2=0.267) between 1RM PB and F200, F100, and F150, respectively, can also be observed. CONCLUSION: In conclusion, this study can demonstrate the existence of statistically significant associations between some of the anthropometric and physical variables and the EIMP Strength variables in Chilean amateur UR players.

OBJETIVO: O objetivo deste estudo é descrever o perfil das variáveis EIMP entre as duas posições de jogo e determinar as possíveis associações com as características antropométricas e qualidades físicas de um grupo de jogadores amadores de rugby chilenos. HIPÓTESE: É por isso que podemos hipotetizar a existência de associações entre as variáveis do EIMP e as qualidades físicas dos jogadores do RU. DESENHO METODOLÓGICO: Este estudo tem um desenho de coorte observacional, descritivo e correlacional. Investigou-se a associação entre as variáveis do EIMP com os testes físicos e as variáveis antropométricas. Trinta e dois jogadores de rugby masculinos de nível amador chileno foram avaliados (média ( DP, idade, 23,3 ( 5,4 anos). RESULTADOS: Para a variável Massa Muscular foram encontradas grandes associações (r=0,53ejercicio y cualidades físicos) (r=0,47) (r=0,44) (r=0,46) com F50, F100, F150 e F200 respectivamente. Grandes associações (R2=0,305) (R2=0,297) (R2=0,267) entre 1RM PB e F200, F100 e F150 respebaloncestotambém podem ser observadas. CONCLUSÃO: Em conclusão, este estudo pode demonstrar a existência de associações estatisticamente significativas entre algumas das variáveis antropométricas e físicas com as variáveis EIMP Força em jogadores amadores do RU chilenos.

Effects of a 12% carbohydrate beverage on tackling technique and running performance during rugby league activity: A randomised, placebo-controlled trial.

The purpose of this study was to investigate the effects of a 12% carbohydrate (CHO) beverage on tackling technique and running performance during rugby league activity. Using a double-blind, placebo-controlled, randomised, crossover design, 15 academy rugby league players ingested a 250 ml bolus of a 12% CHO solution (30 g maltodextrin and 30 g sucrose in 500 ml) 15 minutes before two bouts of rugby activity. The rugby league match simulation for interchange players was used to standardise the movement patterns of activity and provide reliable outcome measures, whilst also reflecting the duration of a typical field-based conditioning session. Measures of tackling technique, external responses (e.g., fatigue index from sprint data) and rating of perceived exertion (RPE) were recorded throughout. Gut discomfort was measured before each bout. The interaction effect was largely compatible with the hypothesis for relative distance (P<0.001, η2 = 0.217) and fairly compatible for tackling technique (P = 0.068, η2 = 0.0640). The time effect for tackling technique, relative and high-intensity distance, sprint, and sprint to contact velocity, time at high metabolic power, PlayerLoad™, and RPE (all P<0.05; η2 = 0.131-0.701) was compatible with the hypothesis. Data for tackling technique, relative and high-intensity distance, sprint, and sprint to contact velocity, sprint, and sprint to contact fatigue index (all P<0.05; η2 = 0.189-0.612) was compatible with a supplement effect overall despite few differences in the pattern of change (interaction). Minimal gut discomfort was reported for the CHO (bout 1 = 27 ± 17; bout 2 = 23 ± 17 AU) and placebo (bout 1 = 23 ± 18 AU; bout 2 = 24 ± 13) trials. This study shows that a 12% CHO beverage before two bouts of standardised rugby activity is a practical and effective strategy for retaining tackling technique, increasing external responses, and reducing RPE without compromising gut comfort.

Repeated sprint training under hypoxia improves aerobic performance and repeated sprint ability by enhancing muscle deoxygenation and markers of angiogenesis in rugby sevens.

OBJECTIVE: To evaluate the effects of repeated sprint (RS) training in hypoxia on aerobic performance, repeated sprint ability (RSA), and muscle oxygenation in Rugby Sevens. METHODS: Fourteen Rugby Sevens players were randomly allocated into hypoxic (RSH, FIO2 = 14.5%, n = 7) or normoxic (RSN, FIO2 = 20.9%, n = 7) groups. Both groups underwent RS training consisting of 3 sets of 6-s × 10 sprints at 140% of velocity at peak oxygen uptake ([Formula: see text]) on a motorized treadmill, 3 days/week for 6 weeks in addition to usual training. Hematological variables, hypoxia-inducible factor-1 alpha (HIF-1α), and vascular endothelial growth factor (VEGF) concentrations were measured. Aerobic performance, RSA, and muscle oxygenation during the running-based anaerobic sprint (RAS) test were analyzed. RESULTS: RSH caused no changes in hemoglobin concentration and hematocrit but significant improvements in [Formula: see text] (7.5%, p = 0.03, ES = 1.07), time to exhaustion (17.6%, p = 0.05, ES = 0.92), and fatigue index (FI, - 12.3%, p = 0.01, ES = 1.39) during the RSA test compared to baseline but not RSN. While ∆deoxygenated hemoglobin was significantly increased both after RSH and RSN (p < 0.05), ∆tissue saturation index (- 56.1%, p = 0.01, ES = 1.35) and ∆oxygenated hemoglobin (- 54.7%, p = 0.04, ES = 0.97) were significantly decreased after RSH. These changes were concomitant with increased levels of HIF-1α and VEGF in serum after RSH with a strong negative correlation between ∆FI and ∆deoxygenated hemoglobin after RSH (r = - 0.81, p = 0.03). CONCLUSION: There was minimal benefit from adding RSH to standard Rugby Sevens training, in eliciting improvements in aerobic performance and resistance to fatigue, possibly by enhanced muscle deoxygenation and increased serum HIF-1α and VEGF concentrations.

Profiling the Post-match Recovery Response in Male Rugby: A Systematic Review.

ABSTRACT: Aben, HGJ, Hills, SP, Cooke, CB, Davis, D, Jones, B, and Russell, M. Profiling the post-match recovery response in male rugby: A systematic review. J Strength Cond Res 36(7): 2050-2067, 2022-To minimize underperformance, injury, and illness, and to enhance readiness for training and match-play, post-match responses are commonly monitored within professional rugby. As no clear consensus exists regarding the magnitude and duration of post-match recovery, this review summarized the literature (17 studies yielded from literature searching/screening) reporting neuromuscular (countermovement jump [CMJ], peak power output [PP], and flight time [FT]), biochemical (creatine kinase [CK]) or endocrine (cortisol [C] and testosterone [T] concentrations), and subjective (wellness questionnaire and muscle soreness) indices after rugby match-play. For neuromuscular responses (11 studies), reductions in PP <31.5% occurred <30 minutes after match, returning to baseline within 48-72 hours. Post-match reductions in FT of <4% recovered after 48 hours. For biochemical and endocrine responses (14 studies), increases in CK, ranging from 120 to 451%, peaked between 12 and 24 hours, returning to baseline within 72 hours of match-play. Initial increases of <298% in C and reductions in T concentrations (<44%) returned to pre-match values within 48-72 hours. Mood disturbances (6 studies) required 48-72 hours to normalize after peak decrements of <65% at 24 hours. This review highlights that 72 hours were needed to restore perturbations in neuromuscular, biochemical and endocrine, and subjective/perceptual responses after competitive rugby match-play. Notably, only 4 studies reported responses in more ecologically valid scenarios (i.e., those in which regular training and recovery strategies were used) while also reporting detailed match demands. A lack of research focusing on youth players was also evident, as only 3 studies profiled post-match responses in younger athletes. Deeper insight regarding post-match responses in ecologically valid scenarios is therefore required.

Evaluation of the impact of the COVID-19 lockdown on the quality of life of patients monitored for cancer who practice an adapted physical activity: rugby for health.

PURPOSE: The benefits of regular physical exercise on the tolerability of cancer treatments, quality of life and survival rates post-diagnosis have been demonstrated but all supervised physical activities have been interrupted due to the global health crisis and the need for lockdown to halt the spread of SARS-CoV-2. To reintroduce activities post-lockdown, we wanted to assess the impact of the COVID-19 lockdown on the quality of life and the psychological status of patients who practice an adapted physical activity such as rugby for health. METHODS: The evaluation was conducted in two phases: an initial self-questionnaire comprised of 42 questions sent to all participants to assess the impact of lockdown and a second assessment phase in the presence of the participants. We assessed anthropometric data, functional fitness parameters, quality of life and the psychosocial status of the subjects. The data were compared to pre-lockdown data as part of a standardised follow-up procedure for patients enrolled in the programme. RESULTS: 105/120 (87.5%) individuals responded to the rapid post-lockdown survey analysis. In 20% of the cases, the patients reported anxiety, pain, a decline in fitness and a significant impact on the tolerability of cancer treatments. Twenty-seven patients agreed to participate in the individual analysis. Following lockdown, there was a significant decrease in the intensity of physical activity (p = 8.223e-05). No post-lockdown changes were noted in the assessments that focus on the quality of life and the level of psychological distress. Conversely, there was a significant correlation between the total of high energy expended during lockdown and the quality of life (p = 0.03; rho = 0.2248) and the level of psychological distress post-lockdown (p = 0.05; rho = - 0.3772). CONCLUSION: Lockdown and reduced physical activity, particularly leisure activities, did not impact the overall health of the patients. However, there was a significant correlation with the level of physical activity since the higher the level of physical activity, the better the quality of life and the lower the level of psychological distress.

A GNSS-based method to define athlete manoeuvrability in field-based team sports.

This study presented a method of quantifying the manoeuvrability of two field-based team sport athletes and investigated its relationship with running velocity during competition. Across a season, 10 Hz Global navigation satellite system (GNSS) devices were worn during matches by 62 athletes (Australian Football League [AFL]; n = 36, 17 matches, National Rugby League [NRL]; n = 26, 21 matches). To quantify manoeuvrability, tortuosity was calculated from the X and Y coordinates from match GNSS files (converted from latitude and longitude). Tortuosity was calculated as 100 x natural logarithm of the chord distance (distance travelled between X and Y coordinates), divided by the straight-line distance. The maximal tortuosity was then quantified for each 0.5 m∙s-1 speed increment, ranging from 0 to the highest value for each game file. A quadratic model was fitted for each match file, controlling for the curvilinear relationship between tortuosity and velocity. A comparison of the quadratic coefficients between sports, and within sport between positions was investigated using linear mixed models. Resulting standard deviations (SDs) and mean differences were then assessed to establish standardized effect sizes (ES) and 90% confidence intervals (CI). A curvilinear relationship exists between maximal tortuosity and running speed, reflecting that as speed increases, athletes' ability to deviate from a linear path is compromised (i.e., run in a more linear path). Compared to AFL, NRL had a greater negative quadratic coefficient (a) (ES = 0.70; 0.47 to 0.93) for the 5 second analysis, meaning that as speed increased, NRL athletes' manoeuvrability reduced at a faster rate than when compared to AFL. There were no positional differences within each sport. GNSS derived information can be used to provide a measure of manoeuvrability tortuosity during NRL and AFL matches. The curvilinear relationship between tortuosity and speed demonstrated that as speed increased, manoeuvrability was compromised.

Body Mass and Body Composition Changes over 7 Years in a Male Professional Rugby Union Team.

The purpose of this study was to investigate longitudinal body mass and body composition changes in one professional rugby union team (n=123), (i) according to position [forwards (n=58) versus backs (n=65)], analysis of players with 6 consecutive seasons of DXA scans (n=21) and, (iii) to examine differences by playing status [academy and international], over 7 years. Players [mean age: 26.8 y, body mass index: 28.9+kg.m2] received DXA scans at fourtime points within each year. A modest (but non-significant) increase in mean total mass (0.8 kg) for professional players was reflected by increased lean mass and reduced body fat mass. At all-time points, forwards had a significantly greater total mass, lean mass and body fat percentage compared to backs (p<0.05). Academy players demonstrated increased total and lean mass and decreased body fat percentage over the first 3 years of senior rugby, although this was not significant. Senior and academy international players had greater lean mass and lower body fat percentage (p<0.05) than non-international counterparts. Despite modest increases in total mass; reflected by increased lean mass and reduced fat mass, no significant changes in body mass or body composition, irrespective of playing position were apparent over 7 years.

Seasonal Changes in Lumbar Multifidus Muscle in University Rugby Players.

PURPOSE: Although smaller lumbar multifidus muscle (LMM) was reported to be a strong predictor of lower limb injury (LLI) in Australian Football League players, LMM morphology has not been investigated in rugby athletes. This study examined seasonal changes in LMM in rugby players and whether LMM characteristics were associated with low back pain (LBP) and LLI. METHODS: Ultrasound examinations of the LMM were acquired in 21 university-level rugby players (12 women, 9 men) at preseason and end-season. LMM cross-sectional area (CSA), thickness at rest, and thickness during submaximal contraction (e.g., contralateral arm lift) measurements in prone and standing were obtained bilaterally at the L5-S1 level. The percent change in LMM thickness during contraction was calculated as follows: [(thicknesscontracted - thicknessrest)/thicknessrest × 100]. Self-reported questionnaires were used to acquire data on LBP and LLI. RESULTS: There was no significant difference in LMM characteristics between preseason and end-season measurements (P > 0.05). Preseason LMM CSA, side-to-side CSA asymmetry, and thickness at rest or during contraction were not associated with LBP or LLI. However, a lower percent thickness change in the standing position was significantly associated with having LBP during the preseason (P = 0.01) and playing season (P = 0.001), as well as LLI during the preseason (P = 0.03). CONCLUSIONS: This study provides preliminary evidence that LMM contractile ability and behavior during functional movement, such as standing, may have important implications for the susceptibility to injury among rugby athletes.

The women inclusion on rugby: perceptions of Brazilian national team players

Aims: Women participation in sport is historically permeated by manifestations of discrimination, especially in male preserve practices. This study aimed to investigate and describe the processes of entry and performance of women athletes in rugby, as well as socio-cultural components of this field in relation to gender differences from the perspective of Brazilian women national senior team players. Methods: Semi-structured interviews with five athletes were performed and data analyzed based on the Grounded Theory method. Results: It was found that there are social barriers for women practice in rugby. By the other hand, better opportunities for the development of an athletic career are more available than in the past. Besides that, it has been perceived that the women players need to constantly prove that they can play hard to legitimize their athletic skills among men players. Conclusions: Even if the women participation in rugby is in a changing process of acceptance, barriers still need to be broken for a full social legitimation of these players' practice.(AU)