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1.
Int J Sports Physiol Perform ; 19(1): 80-83, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37917965

RESUMO

PURPOSE: To investigate the effect of cycling-based repeated-sprint training in hypoxia versus in normoxia on single overground running sprint performance and associated force-velocity (F-V) profile in world-class female rugby sevens players. METHODS: Eighteen world-class female rugby sevens players were randomly assigned to repeated-sprint cycling training in normobaric hypoxia (n = 9) or normoxia (n = 9) groups. Training consisted of 4 sessions of repeated-sprint cycling training in normobaric hypoxia or in normoxia (4 × 5 × 5-s cycle sprints-25-s intersprint recovery performed in simulated altitude of ∼5000 m or in normoxia with 3-min interset rest in normoxia for both groups) in addition to rugby sevens training and strength and conditioning sessions within a 9-day intervention period before an international competition. Before and 1 day after the intervention, single 50-m overground running "all-out" sprint performance and associated F-V-related mechanical output were assessed. RESULTS: No interaction (group × time; all P > .088), time effect (before vs 1 d after; all P > .296), or group effect (repeated-sprint cycling training in normobaric hypoxia vs in normoxia; all P > .325) was detected for 50-m overground running sprint performance and any derived F-V profiling variables. CONCLUSIONS: Four sessions of repeated-sprint training either in hypoxia or in normoxia performed over 9 days had no influence on single 50-m overground running sprint performance and associated F-V profile. In world-class female rugby sevens players, the intervention (training camp before an international competition) might have been too short to induce measurable changes. It is also plausible that implementing a similar program in players with likely different F-V profile may result in negligible mechanical effect.


Assuntos
Desempenho Atlético , Corrida , Feminino , Humanos , Altitude , Ciclismo , Hipóxia
2.
Int J Sports Physiol Perform ; 18(9): 1004-1011, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527820

RESUMO

PURPOSE: In women's rugby, players regularly interchange between the rugby sevens (R7) and rugby union (RU) formats. Yet, the game demands and particularly the physical aspects respective to both formats vary and players must be able to respond accordingly. The aim of this study was to compare peak running demands in R7 and RU players. METHODS: A total of 51 international women players participated. HSBC World Sevens Series (n = 19) and Six Nations Rugby Union tournament matches (n = 10) were analyzed for a total of 437 individual match observations. Global positioning systems were utilized to measure total (in meters) and high-speed (above 16 km·h-1, in meters) distance and frequency of accelerations (above 2.5 m·s-2, n) during different rolling-average periods (1-7 min) to obtain peak running activity values. Power law modeling was used to obtain slope and intercept. For all variables, peak values and the value at the 90th percentile (P90) were analyzed. RESULTS: No intercept difference (P = .25; -0.12 ± 0.17) was observed between formats for total distance (161 vs 155 m·min-1). In contrast, R7 players reported a higher intercept (P = .01; -0.29 ± 0.17) for high-speed distance (66 vs 51 m·min-1), while the intercept was higher (P = .01; 0.31 ± 0.20) in RU for accelerations performed (6.1 vs 5.4 n·min-1). Regarding P90, higher values (P < .001) were observed in R7 for total and high-speed distance and accelerations. CONCLUSIONS: While peak overall intensity was similar, P90 on the high-speed spectrum was higher in R7. Information on the most demanding match-play periods specific to both women's rugby formats can inform training specificity by tailoring sessions to ensure sufficient exposure to these peak demands and, consequently, aid transitioning between formats.


Assuntos
Desempenho Atlético , Futebol Americano , Corrida , Humanos , Feminino , Rugby , Aceleração , Sistemas de Informação Geográfica
3.
Med Sci Sports Exerc ; 55(10): 1923-1932, 2023 10 01.
Artigo em Inglês, Francês | MEDLINE | ID: mdl-37259251

RESUMO

PURPOSE: The objective of this study is to investigate the effectiveness of novel repeated-sprint training in hypoxia (RSH) protocol, likely maximizing hypoxic stimulus (higher than commonly used) while preserving training quality (interset rest in normoxia). METHODS: Twenty-three world-class female rugby sevens players performed four repeated-sprint training sessions (4 sets of 5 × 5-s cycle sprints-25-s intersprint recovery and 3-min interset rest) under normobaric hypoxia (RSH, exercise and interset rest at FiO 2 of 10.6% and 20.9%, respectively; n = 12) or normoxia (repeated-sprint training in normoxia; exercise and interset rest at FiO 2 of 20.9%; n = 11) during a 9-d training camp before international competition. Repeated-sprint ability (8 × 5-s treadmill sprints-25-s recovery), on-field aerobic capacity, and brachial endothelial function were assessed pre- and postintervention. RESULTS: Arterial oxygen saturation (pooled data: 87.0% ± 3.1% vs 96.7% ± 2.9%, P < 0.001) and peak and mean power outputs (sets 1 to 4 average decrease: -21.7% ± 7.2% vs -12.0% ± 3.8% and -24.9% ± 8.1% vs -14.9% ± 3.5%; both P < 0.001) were lower in RSH versus repeated-sprint training in normoxia. The cumulated repeated-sprint distance covered significantly increased from pre- to postintervention (+1.9% ± 3.0%, P = 0.019), irrespective of the condition ( P = 0.149). On-field aerobic capacity did not change (all P > 0.45). There was no significant interaction (all P > 0.240) or condition main effect (all P > 0.074) for any brachial artery endothelial function variable. Only peak diameter increased ( P = 0.026), whereas baseline and peak shear stress decreased ( P = 0.014 and 0.019, respectively), from pre- to postintervention. CONCLUSIONS: In world-class female rugby sevens players, only four additional repeated-sprint sessions before competition improve repeated-sprint ability and brachial endothelial function. However, adding severe hypoxic stress during sets of repeated sprints only did not provide supplementary benefits.


PURPOSE: The objective of this study is to investigate the effectiveness of novel repeated-sprint training in hypoxia (RSH) protocol, likely maximizing hypoxic stimulus (higher than commonly used) while preserving training quality (interset rest in normoxia). METHODS: Twenty-three world-class female rugby sevens players performed four repeated-sprint training sessions (4 sets of 5 × 5-s cycle sprints­25-s intersprint recovery and 3-min interset rest) under normobaric hypoxia (RSH, exercise and interset rest at FiO 2 of 10.6% and 20.9%, respectively; n = 12) or normoxia (repeated-sprint training in normoxia; exercise and interset rest at FiO 2 of 20.9%; n = 11) during a 9-d training camp before international competition. Repeated-sprint ability (8 × 5-s treadmill sprints­25-s recovery), on-field aerobic capacity, and brachial endothelial function were assessed pre- and postintervention. RESULTS: Arterial oxygen saturation (pooled data: 87.0% ± 3.1% vs 96.7% ± 2.9%, P < 0.001) and peak and mean power outputs (sets 1 to 4 average decrease: −21.7% ± 7.2% vs −12.0% ± 3.8% and −24.9% ± 8.1% vs −14.9% ± 3.5%; both P < 0.001) were lower in RSH versus repeated-sprint training in normoxia. The cumulated repeated-sprint distance covered significantly increased from pre- to postintervention (+1.9% ± 3.0%, P = 0.019), irrespective of the condition ( P = 0.149). On-field aerobic capacity did not change (all P > 0.45). There was no significant interaction (all P > 0.240) or condition main effect (all P > 0.074) for any brachial artery endothelial function variable. Only peak diameter increased ( P = 0.026), whereas baseline and peak shear stress decreased ( P = 0.014 and 0.019, respectively), from pre- to postintervention. CONCLUSIONS: In world-class female rugby sevens players, only four additional repeated-sprint sessions before competition improve repeated-sprint ability and brachial endothelial function. However, adding severe hypoxic stress during sets of repeated sprints only did not provide supplementary benefits.


Assuntos
Desempenho Atlético , Condicionamento Físico Humano , Humanos , Feminino , Rugby , Altitude , Hipóxia , Condicionamento Físico Humano/métodos
4.
Front Sports Act Living ; 5: 1120162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090820

RESUMO

Introduction: The study aimed to interpret the evolution of the physical performance of rugby sevens and rugby union French international players from 2009 to 2020. Methods: 631 players from the French national teams were divided into three groups: forwards, backs and sevens. The performances evaluated were anthropometric characteristics, strength tests (1 RM bench press and 1 RM pull-up), aerobic capacity (YoYo IR1 test) and speed tests (10 m, 20 m and 50 m). The best performance of each player over a two-year period was kept for the analysis. Fluctuations were observed across the decade. Results: The anthropometric characteristics of female rugby sevens players tend to be taller and lighter than rugby union players. In rugby sevens, a moderate increase in maximal aerobic capacity was observed while sprint performances remained similar. Improvements in height and weight were observed over the last 10 years in rugby union players with a difference between the position. A moderate increase in sprinting performances and strength were observed both in backs and forwards. Discussion: The overall improvement of strength and conditioning performances and anthropometrical evolution reflects the rugby environment characterized by the arrival of professional contracts and the structuration process of the clubs which allows a better quality of training and easier access to the infrastructures of the very high level.

5.
J Strength Cond Res ; 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30676389

RESUMO

ABSTRACT: 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.

6.
Sports Biomech ; 22(7): 863-873, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32538689

RESUMO

This study describes asymmetry in the main running mechanical variables during repeated treadmill sprints in elite female athletes and examines whether inter-limb differences in sprinting mechanics increase with fatigue. Eighteen elite female players (French national Rugby Sevens team) performed 8 × 5-s sprints (25-s rest) on an instrumented motorised sprint treadmill. The group mean 'symmetry angle' (SA) scores were ~1-2% for contact time (1.6 ± 0.6%), aerial time (2.1 ± 0.8%), step frequency (1.3 ± 0.5%) and step length (1.6 ± 0.6%). Mean vertical and horizontal forces, vertical and leg stiffness presented SA values of 1.7 ± 1.5%, 2.4 ± 1.2%, 2.6 ± 0.2% and 2.5 ± 0.2%, respectively. The SA scores were ~2-8% for duration of braking (6.9 ± 5.0%) and propulsive (6.5 ± 4.4%) phases, peak braking (6.5 ± 2.5%) and propulsive (1.6 ± 0.9%) forces as well as net (5.8 ± 5.6%), braking (7.7 ± 5.3%) and propulsive (2.7 ± 1.6%) impulses. However, there was no influence of sprint repetition number on SA scores for tested variables (P > 0.05). In elite female Rugby Sevens players, there was no noticeable difference in asymmetries for the great majority of stride mechanical variables during repeated treadmill sprints.


Assuntos
Desempenho Atlético , Corrida , Humanos , Feminino , Rugby , Fenômenos Biomecânicos , Teste de Esforço
7.
J Sports Med Phys Fitness ; 61(8): 1091-1097, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34264043

RESUMO

BACKGROUND: This study compared the physical performance of National female rugby sevens players selected or not selected to form the Brazilian National Olympic team. METHODS: Thirty women rugby sevens players from the Brazilian National team (15 Olympic and 15 non-Olympic athletes) participated in this study. Tests were performed on consecutive days, in the following order: day 1) standing long jump (SLJ); squat and countermovement jumps (SJ and CMJ); and one-repetition maximum test in the bench-press, prone-row, and parallel squat exercises; day 2) 40-m linear sprint; Pro-agility and L-drill change of direction tests; and Yo-Yo intermittent recovery test level 1 (IR1). The differences between groups in all variables examined were analyzed using the independent t test and effect sizes (ES). RESULTS: Greater jump performances were noticed for the Olympic players in all jump tests compared to the non-Olympics (ES=0.95, ES=1.05, and ES=0.93, for SLJ, SJ, and CMJ, respectively; P<0.05). Olympics revealed shorter sprint times than non-Olympics in 40-m distance (ES=0.88; P<0.05). Higher one-repetition maximum in the bench-press and Yo-Yo IR1 distance were also observed for the Olympics in comparison to non-Olympic players (ES=0.65 and 0.93, respectively; P<0.05). CONCLUSIONS: Lower-body power, upper-body strength, maximal sprint velocity and aerobic fitness were found to be important for distinguishing between Olympic and non-Olympic female rugby sevens players. Coaches and practitioners should prioritize the development of these physical qualities in these team-sport athletes.


Assuntos
Desempenho Atlético , Futebol Americano , Atletas , Exercício Físico , Feminino , Humanos , Desempenho Físico Funcional
8.
Int J Sports Physiol Perform ; 13(3): 255-267, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28771098

RESUMO

Rugby sevens, a sport new to the Olympics, features high-intensity intermittent running and contact efforts more than short match durations, normally 6 times across 2 to 3 d in a tournament format. Elite rugby sevens seasons often include over a dozen competitive tournaments over less than 9 months, demanding deliberate and careful training-stress balance and workload management alongside development of the necessary physical qualities required for competition. Focus on running and repeated power skills, strength, and match-specific conditioning capacities is advised. Partial taper approaches in combination with high-speed running (>5 m/s from GPS measures) before and between tournaments in succession may reduce injury rates and enhance performance. In a sport with substantial long-haul intercontinental travel and repetitive chronic load demands, management of logistics including nutrition and recovery is inclusive of the formula for success in the physical preparation of elite rugby sevens athletes.


Assuntos
Desempenho Atlético , Futebol Americano , Condicionamento Físico Humano , Atletas , Comportamento Competitivo , Humanos , Corrida
9.
Int J Sports Physiol Perform ; 12(7): 901-907, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27918679

RESUMO

PURPOSE: To investigate the running demands and associated metabolic perturbations during an official rugby sevens tournament. METHODS: Twelve elite players participated in 7 matches wearing GPS units. Maximal sprinting speed (MSS) and maximal aerobic speed (MAS) were measured. High-intensity threshold was individualized relative to MAS (>100% of MAS), and very-high-intensity distance was reported relative to both MAS and MSS. Blood samples were taken at rest and after each match. RESULTS: Comparison of prematch and postmatch samples revealed significant (P < .01) changes in pH (7.41-7.25), bicarbonate concentration ([HCO3-]) (24.8-13.6 mmol/L), and lactate concentration ([La]) (2.4-11.9 mmol/L). Mean relative total distance covered was 91 ± 13 m/min with ~17 m/min at high-intensity. Player status (whole-match or interchanged players), match time, and total distance covered had no significant impact on metabolic indices. Relative distance covered at high intensity was negatively correlated with pH and [HCO3-] (r = .44 and r = .42, respectively; P < .01) and positively correlated with [La] (r = .36; P < .01). Total distance covered and distance covered at very high intensity during the 1-min peak activity in the last 3 min of play were correlated with [La] (r = .39 and r = .39, respectively; P < .01). CONCLUSIONS: Significant alterations in blood-metabolite indices from prematch to postmatch sampling suggest that players were required to tolerate a substantial level of acidosis related to metabolite accumulation. In addition, the ability to produce energy via the glycolytic energy pathway seems to be a major determinant in match-related running performance.


Assuntos
Acidose/sangue , Futebol Americano/fisiologia , Corrida/fisiologia , Adulto , Atletas , Bicarbonatos/sangue , Sistemas de Informação Geográfica , Humanos , Ácido Láctico/sangue , Masculino , Movimento , Adulto Jovem
10.
Int J Sports Physiol Perform ; 12(2): 218-223, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27193485

RESUMO

PURPOSE: To compare the sensitivity of a sprint vs a countermovement-jump (CMJ) test after an intense training session in international rugby sevens players, as well as analyze the effects of fatigue on sprint acceleration. METHODS: Thirteen international rugby sevens players completed two 30-m sprints and a set of 4 repetitions of CMJ before and after a highly demanding rugby sevens training session. RESULTS: Change in CMJ height was unclear (-3.6%; ±90% confidence limits 11.9%. Chances of a true positive/trivial/negative change: 24/10/66%), while a very likely small increase in 30-m sprint time was observed (1.0%; ±0.7%, 96/3/1%). A very likely small decrease in the maximum horizontal theoretical velocity (V0) (-2.4; ±1.8%, 1/4/95%) was observed. A very large correlation (r = -.79 ± .23) between the variations of V0 and 30-m-sprint performance was also observed. Changes in 30-m sprint time were negatively and very largely correlated with the distance covered above the maximal aerobic speed (r = -.71 ± .32). CONCLUSIONS: The CMJ test appears to be less sensitive than the sprint test, which casts doubts on the usefulness of a vertical-jump test in sports such as rugby that mainly involve horizontal motions. The decline in sprint performance relates more to a decrease in velocity than in force capability and is correlated with the distance covered at high intensity.


Assuntos
Teste de Esforço/métodos , Futebol Americano/fisiologia , Fadiga Muscular/fisiologia , Condicionamento Físico Humano/métodos , Aceleração , Adulto , Frequência Cardíaca , Humanos , Masculino , Percepção , Esforço Físico/fisiologia , Exercício Pliométrico
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