ORIGINAL RESEARCH Movement patterns and

Journal of Strength and Conditioning Research Publish Ahead of Print DOI: 10.1519/JSC.0000000000001866

ORIGINAL RESEARCH

Movement patterns and muscle damage during simulated rugby sevens matches in

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National team players

Ramos4, Irineu Loturco1

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Lucas A. Pereira1, Fábio Y. Nakamura1,2, José E. Moraes3, Katia Kitamura1, Solange P.

NAR – Nucleus of High Performance in Sport, São Paulo, Brazil;

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Department of Physical Education, State University of Londrina, Parana, Brazil;

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Brazilian Rugby Confederation, São Paulo, Brazil;

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Departament of Histology, State University of Londrina, Parana, Brazil.

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Running head: Match running performance in rugby sevens

*Corresponding Author:

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Lucas A. Pereira

Av. Padre José Maria, 555 - Santo Amaro, 04753-060 – São Paulo, SP, Brazil. e-mail: [email protected]

Copyright ª 2017 National Strength and Conditioning Association

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ABSTRACT The aim of this study was to analyze the match performance (i.e., distance covered in

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different intensities), signs of muscle damage (assessed by means of creatine kinase [CK]

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activity and rate of force development [RFD]), and neuromuscular fatigue (using linear sprint

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and vertical jump performances) following three single-day simulated matches performed by

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rugby sevens players from the Brazilian National Team. Ten male rugby sevens players (25.2

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± 3.6 years; 88.7 ± 7.1 kg; 182.2 ± 6.3 cm) participated in this study. On the day prior to the

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matches, the athletes performed a 40-m sprint, a vertical jump assessment and a maximal

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isometric force test. In the morning of the match day, blood samples were collected to analyze

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the CK activity. Afterwards, three simulated rugby sevens’ matches were performed with 2-h

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intermission periods. The match performance (encompassing total distance and distance

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covered in different velocity ranges and body loads [BL]) were obtained from global

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positioning system units. The statistical analysis was performed by using a mixed model

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approach and the effect sizes (ES) of the differences. The statistical significance level was set

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at P< 0.05. Players were capable of maintaining the match performance when comparing the

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first and last games. Large (ES >0.8) and significant (P< 0.05) reductions were demonstrated

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in the total distance and BL when comparing the 2nd with the 1st halves. Decrements in the

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explosive force capacity (assessed by means of RFD) and the squat jump were noticed (ES

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varying from 0.55 to 1.14; P< 0.05). The CK activity increased after the matches (ES = 1.29;

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P< 0.05). The rugby sevens players were able to maintain the physical performance across

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three successive matches simulating the first day of a tournament. The augmented CK activity

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and the decreases in the squat jump and RFD suggest that increased levels of muscle damage

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were experienced on the day after the matches. Therefore, the technical staff are encouraged

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to implement recovery strategies and planned substitutions during multi-day tournaments in


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order to reduce the impact of accumulated fatigue and muscle damage on subsequent match

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performance. In addition, specific training strategies aimed at better simulating the match

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demands need to be implemented in the players’ training routines.

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Keywords: team sports, ball games, recovery, performance analysis

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INTRODUCTION

Rugby sevens took part of the Olympic Games in Rio 2016 for the first time. In the

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rugby sevens, the rules and field dimensions are the same as in the 15-player rugby union,

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except for the fact that the game is played by 7 players per team, in two halves with a duration

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of 7-min each, and with a 2-min half-time interval. Remarkably, it has been shown that the

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average velocity maintained during the rugby sevens matches is higher than in rugby union

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(7, 26). Therefore, due to the high-intensity efforts demanded throughout these games (12, 14,

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30), athletes are required to excel in speed, muscle power and aerobic and anaerobic

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capacities in order to efficiently cope with the specific sport demands. In addition to physical

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fitness development, maintenance of nutritional and hydration status throughout the

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tournaments is fundamental for athletes to deal with rugby sevens match demands (8).

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Rugby sevens tournaments are generally contested over 2 consecutive days,

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comprising 5-7 matches with ≈3-h intervals between successive games. The sequential

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matches may lead to fatigue accumulation and reduced match performance (i.e., distance

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covered in different intensities) across the tournament. Although only trivial to small

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decrements in the match performance of rugby sevens players have been reported from the

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first to the second halves (12, 30), between-match comparisons are less prevalent in the

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literature. One study analyzing match-to-match performance variations showed unclear to

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moderate differences in movement patterns (i.e., number of accelerations performed and


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distance covered in different intensities) between the first pool match on day one and the last

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knock out finals match on day two in international level male players (13), while in females it

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appears that match performance is largely reduced in similar competition settings (3).

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However, it is currently unknown whether rugby sevens players experience physical

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performance impairments during the first day of competition, leading to deterioration of the

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neuromuscular/physiological traits and, consequently, hampering the athletes’ performance on

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the second day. To date, a recent study (37) with female National and State level players

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showed moderately attenuated vertical jump performance, a large increase in muscle soreness

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and a very large increase in circulating creatine kinase (CK) by the end of the tournament.

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Accordingly, decrements in countermovement jump performance related to prolonged

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neuromuscular fatigue and muscle damage were reported for up to 7 days’ post-tournament

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stages (37). As such, previous studies have shown that high physical demands of high-

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intensity running, disputes and collisions acutely induce significant increases in post-game

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circulating muscle damage markers (e.g., CK) and inflammatory mediators (e.g., neutrophils

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and interleukin [IL]-6) immediately after two consecutive rugby sevens matches (31), and

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between 14- and 48-h after rugby union (5) and soccer matches (28).

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Confirming the existence of signs of neuromuscular fatigue (i.e., reduced vertical

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jump and sprint performances and decreases in the rate of force development [RFD]) and

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muscle damage (i.e., increased level of CK activity) at the start of the second day of

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competition in rugby sevens players would highlight the necessity of implementing nutritional

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interventions trying to maintain glycogen levels and hydration status (8); to employ effective

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recovery strategies at the end of day one (e.g., cold water immersion) (6); and to develop

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more effective training strategies aiming to enhance the physical fitness components

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necessary to allow players to better cope with the high match demands (15). Furthermore,

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these “physical impairments” from the first to the second day could be a criterion to spare a


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player from full-match participation on the second day of competition. Therefore, the aim of

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this study was to analyze the match performance (i.e., distance covered in different intensities

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and body load), signs of muscle damage (i.e., CK activity and RFD), inflammatory status

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(assessed by means of IL-6, tumor necrosis factor [TNF] α and IL-10), and neuromuscular

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fatigue (i.e., vertical jump and sprint performances, maximum isometric force and RFD)

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following three single-day simulated matches performed by rugby sevens players from the

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Brazilian National Team.

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METHODS

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Experimental approach to the problem

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This observational study was designed to simulate the first day of a rugby sevens

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tournament played over three consecutive matches. Figure 1 displays the schematic

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representation of the study scheme. On the day prior to the matches (in the afternoon), the

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athletes performed a 40-m sprint, a vertical jump assessment (squat and countermovement

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jumps) and a maximal isometric force test in the half-squat exercise (baseline physical

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testing). On the day of the matches, in the morning (at 8:00 am), blood samples were

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collected (baseline measurements). Afterwards, three simulated rugby sevens matches were

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performed with 2-h intermission periods. The match performance (encompassing total

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distance and distance covered in different velocity ranges and body loads) were obtained from

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global positioning system (GPS) units. Prior to physical testing on day 1 and day 3 and before

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each match, a 10-min standardized warm-up involving self-selected low-intensity runs for 5

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minutes followed by active stretching and submaximal jumps and runs was supervised by the

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coaching staff. The matches were played in accordance with the rules of the World Rugby

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(IRB) and under the control of an experienced referee. All the players participated in the

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entire three matches. Finally, on the next day, the athletes returned to the testing facilities


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between 8:00am and 12:00pm. Blood samples were drawn and the physical tests were

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repeated following the same order as used in the baseline measurements. All assessments

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were performed between 15- and 17-h after the final simulated match (“post” measurements).

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The same experienced person performed all physical assessments and the athletes were not

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allowed to use any recovery method or substance capable of affecting the study outcomes

***INSERT FIGURE 1 HERE***

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Participants

Ten male rugby sevens players (25.2 ± 3.6 years; 88.7 ± 7.1 kg; 182.2 ± 6.3 cm)

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from the Brazilian National team participated in the study. The players competed at

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professional level and trained 10 to 12-h per week. Although athletes did not train in the same

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place on a daily basis, they trained under the same training regime, supervised by the

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coaching staff of the Brazilian National team. In addition, they took part in several training

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camp weekends throughout the season in order to develop their technical and physical

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abilities equally. From the 10 players, 7 comprised one team and the other 3 formed part of

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the other team. To complete the second team, 4 players of the same competitive level

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participated solely in the simulated matches, and did not take part in any other experimental

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testing. From the 14 players involved in the matches, only ten were monitored due to the

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availability of the GPS units. The two teams were formed by the coaching staff, matching the

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athletes in terms of physical and technical performances. Prior to commencing the study,

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participants were briefed about the experimental design and signed an informed consent form.

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The study was approved by the local Ethics Committee.

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Match performance The game movement patterns of the rugby matches were obtained from the GPS

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units, sampling at 5-Hz (SPI Elite, GPS ports Systems, Australia). The equipment was fitted

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to the upper back of each player using an adjustable neoprene harness. The GPS contained a

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tri-axial accelerometer system (sampling at 100-Hz) which was used to quantify body

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accelerations. The units were turned on during the warm-up, to allow satellite detection, and

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placed in the harness immediately prior to the kick-off.

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The velocity ranges were selected based on a previous study (30). The match

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activities were divided into the following categories: walking (0-6.0 km.h-1), jogging (6.1-12.0

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km.h-1), cruising (12.1-14.0 km.h-1), striding (14.1-18.0 km.h-1), high-intensity running (18.1-

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20.0 km.h-1) and sprinting (>20.1 km.h-1).

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The acceleration vector magnitude as a function of time (i) (AVM) was obtained

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from x (lateral), y (frontal/back) and z (vertical) axis components (i.e., acx, acy and acz,

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respectively) obtained from the 100 Hz accelerometer system, using the following equation:

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Finally, the body load (BL) was calculated as the accumulated sum of all acceleration vector

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magnitude values obtained across the matches. Since the distance covered in different

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of the GPS system (5-Hz) in detecting short, but intense movements, such as

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accelerations/decelerations and collisions, the BL has been used as an important tool for

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match performance monitoring that quantifies all kind of movements performed by players

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during the matches (10, 11). The BL results were divided by 100 in order to simplify the

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expression and presentation.

intensities could underestimate the actual physical demands of the match due to the incapacity


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Neuromuscular fatigue

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The neuromuscular fatigue was assessed by means of three different physical

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measures: (1) the vertical jumping height, (2) the 40-m linear speed, and (3) the maximal

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isometric force and the RFD applied in the half squat exercise. The vertical jump height was assessed through squat and countermovement jumps (SJ

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and CMJ, respectively). The athletes performed five attempts, with a 15-s interval between

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each jump. In the SJ, a static position with a 90° knee-flexion angle was maintained for 2-s

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before a jump attempt without any preparatory movement. In the CMJ, athletes were

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instructed to execute a downward movement followed by a complete extension of the legs. To

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avoid changes in the jumping coordination pattern, the amplitude of the countermovement

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was freely determined. All jumps were executed with the hands on the hips. The jumps were

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performed on a contact platform (Smart Jump; Fusion Sport, Coopers Plains, Australia) with

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the recorded flight time (t) being used to estimate the height (h) of the rise of the body’s

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centre of gravity during the vertical jump (i.e., h = gt²/8, where g = 9.81 m·s-2). The best

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attempt was retained for data analysis.

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Prior to the execution of the maximum speed test, two pairs of photocells (Smart

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Speed®, Fusion Sport, Coopers Plains, Australia) were positioned at distances of 0- and 40-

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m. The athletes sprinted twice, starting from a standing position, 0.5-m behind the start line. A

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5-min rest interval was allowed between the two attempts, and the fastest time was retained for analysis.

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Maximal isometric force and RFD in the half-squat exercise were determined using a

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Smith-machine (Technogym Equipment, Italy), positioned over a force platform with custom

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designed software (AccuPower, AMTI, USA), sampling at a rate of 400-Hz (36). The initial

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position of each test was validated by an experienced test administrator, who set and fixed the


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bar on the safety pins at a height corresponding to ≈90° of knee flexion (to maximize the

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force application) (8). After an initial command, subjects were instructed to push as hard and

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fast as possible against a fixed pre-set bar, sustaining the muscle contraction for 5-s. The

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maximal

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achieved/collected over the force-time curve during the course of 5-s. RFD was determined as

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the slope of the isometric force-time curve over the time-intervals of 0-100 ms (RFD100) and

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0-200 ms (RFD200) (1, 34).Additionally, the variation in the RFD in the 100-200 ms (RFD100-

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200)

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marker of exercise-induced muscle damage and neuromuscular fatigue. Strong verbal

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encouragement was provided during the tests.

force

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interval was calculated, since Peñailillo, et al. (24) reported that this interval is a sensitive

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maximum

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isometric

Muscle damage markers and Cytokines

Blood samples (5-ml) were collected from an antecubital arm vein into evacuated

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tubes containing ethylenediaminetetraacetic acid (EDTA). Plasma was separated by

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centrifugation (1,500 g, 4ºC, 10-min). Samples were collected prior to and between 15 and

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17-h after the final match. The time for blood sample collection was determined in accordance

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with the timetable defined by the technical staff. Plasma concentration of IL-6, TNFα, and IL-

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10 were determined by enzyme linked immunosorbent assay (ELISA), using commercial kits

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(Becton and Dickinson, Franklin Lakes, USA) according to the manufacturer’s instructions.

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analyzer (Dimension EXLTM Chemistry System, Siemens, Munich, Germany). All cytokines

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and CK analyses were performed with duplicate.

Creatine kinase activity was determined using a commercial kit in an automated biochemical

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Statistical analyses The Shapiro-Wilk test was used to check the data normality. To compare the CK

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activity and cytokines and the performance in the physical tests (at baseline and after the

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simulated matches), a paired t-test was used. A linear mixed model analysis was used to

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compare the distance covered in different ranges of velocities and also to compare the body

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load accumulated between match halves (during each of the three matches and between-

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matches). This approach is used in general linear models with repeated measures and has the

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ability to compare the slope among curves (i.e., rate of change in the distance covered across

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the matches) (35). Accordingly, two factors were included for analyses: match number and

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period (i.e., first and second halves). The Tukey’s post-hoc test identified where the possible

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differences occurred. The level of statistical significance was set at P< 0.05. Finally, the

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magnitudes of the differences for the comparisons in all variables were analyzed using the

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Cohen’s d effect size (ES) and its confidence intervals (CI) (4).The magnitudes of the ESs

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were qualitatively interpreted using the following thresholds: 0.8, large (4).

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RESULTS

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Table 1 demonstrates the comparisons of the total distance and the distance covered in

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the different velocity ranges among the three consecutive matches. The distance covered in

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the 0-6 km.h-1 and 6-12 km.h-1 velocity ranges in match 3 was significantly shorter than in

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matches 1 and 2, respectively (16.2% and 9.2% of difference; P< 0.05). During match 2,

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athletes covered greater distances in the 6-12 km.h-1 and 12-14 km.h-1 velocity ranges in

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relation to match 1 (15.8% and 19.2% of difference, respectively; P< 0.05), while covering

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shorter distance in sprinting (>20 km.h-1) than during match 1 (50.5% of difference; P< 0.05).


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No differences in BL were observed comparing the three matches (match 1: 977.8 ± 26.8 a.u.;

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match 2: 975.6 ± 27.3 a.u.; match 3: 973.4 ± 18.6 a.u., P> 0.05).

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***INSERT TABLE 1 HERE***

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Figure 2 shows the comparisons between the 1st and 2nd halves for total distance and

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distance covered in the different velocity ranges. The athletes covered a shorter total distance

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and shorter distances in jogging (6-12.0 km.h-1), cruising (12.0-14.0 km.h-1), and striding

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(14.0-18.0 km.h-1) in the 2nd half compared to the 1st half (ES [90% CI] % of difference: -1.30

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[-2.02; -0.42] 9.6%, -1.33 [-1.86; -0.29] 20.7%, -1.52 [-2.40; -0.72] 31.8%, -0.92 [-1.65; -

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0.11] 21.4%, respectively; P< 0.05). The distance covered walking (0-6 km.h-1) was

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significantly greater in the 2nd half than in the 1st half (ES: 1.72 [0.69; 2.36] 19.1%; P< 0.05).

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No difference was observed in the distance covered at high-intensity (18.0-20.0 km.h-1) and

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sprinting (>20 km.h-1) between the two halves (ES: -0.43 [-1.20; 0.29], -0.04 [-0.77; 0.70],

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respectively; P> 0.05). Figure 3 shows the comparison of the BL between the 1st and 2nd

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halves. The 2nd half presented a significantly lower BL compared to the 1st half (ES: -1.28 [-

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2.00; -0.40] 3.5%; P< 0.05).

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Table 2 shows the comparisons of the physical test results at baseline and following

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the three consecutive rugby sevens matches. The SJ and RFD measured in 0-100 ms, 0-200

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ms, 100-200 ms were significantly lower in the post- than in the baseline-tests (5.7%, 28.8%,


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26.7%, and 23.1% of difference, respectively; P< 0.05). No significant differences were

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observed in the CMJ, 40-m sprinting speed, or maximum isometric force comparing the

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baseline with the post-assessments. Table 3 displays the serum CK activity and cytokine concentration at baseline and 15-

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h after the final match. The CK activity was significantly higher in the post- than in the

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baseline-measurements (83.2% of difference; P< 0.05). No significant differences were

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observed in the cytokine concentration comparing the two moments (i.e., baseline vs post-

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measurements; P> 0.05).

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DISCUSSION

The main finding of this study was that the investigated players were capable of

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maintaining the activity profile and intensity of the match, between the first and last matches

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on the first day of a simulated rugby sevens tournament. Significant reductions with a large

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effect size were demonstrated in the total distance and BL when comparing the 2nd with the 1st

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half of all games combined. In the physical tests (performed 15-h after the matches), there

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were decrements in the SJ height and in the RFD (assessed in 0-100, 0-200, and 100-200 ms)

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obtained from the half-squat maximal isometric force test. The CK activity increased 15-h

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after the matches, whereas inflammatory cytokines did not substantially change from

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baseline. These results suggest that the rugby sevens players experienced substantial levels of

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muscle damage and neuromuscular fatigue (i.e., increased CK activity and reduced RFD)


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which was accompanied by decreased performance in the vertical jump height 15-h after three

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simulated rugby sevens matches. The total distance (1413.3-m per match on average) and the distance covered at high-

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intensity (80.1-m per match on average) and sprinting (146.7-m per match on average) during

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matches reported herein are strictly in line with previous studies that analyzed national and

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international level rugby sevens players (13, 27, 30). For instance, Suarez-Arrones, et al. (30)

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demonstrated that during national level matches, these athletes might cover a total of 1500-m,

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being 79.5-m at high-intensity efforts and 137.7-m at maximal sprinting speed. Furthermore,

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although using a slightly different threshold for detecting sprinting (i.e., 21.6 km.h-1), a

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previous study (13) demonstrated higher total distance (120 m.min-1) and similar distance in

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sprinting (11.5 m.min-1) during domestic and international matches in comparison to those

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observed in our study (101 m.min-1 and ≈10.5 m.min-1, respectively). Meanwhile, Ross, et al.

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(27) revealed that sevens players could cover a total of 105 m.min-1, 9 m.min-1 being in

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sprinting, during provincial and/or international matches. Together, these data suggest that the

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intensity of the sevens matches investigated in the present study is comparable with those

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already observed during top-level matches (13, 27, 30).

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A previous study analyzing the profile of players’ activities over a rugby sevens

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tournament showed only small reductions in the distance covered in low-intensity running

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(90% maximal

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heart rate increased in the second half (in comparison with the first half). Moreover, when

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compared with athletes who participated in the entire match, the substitute players covered

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greater distances while running at high intensities during the 2nd half (13). From an applied

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standpoint, these results indicate that, despite the absence of signs of permanent fatigue

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throughout successive matches, temporary fatigue can be observed during each match.

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Although the mechanisms underlying fatigue experienced during the matches were not fully

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elucidated, some studies have already suggested that this could be caused by metabolic and

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neural disturbances, such as ionic imbalances and central fatigue (2, 20, 33). It is important to

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note that we did not permit substitutions of the monitored players during the three matches; as

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aforementioned, substitute players may cover higher distances when compared with players

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involved in the entire match, which could compromise the objectives of our investigation (14,

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The increased blood CK activity suggests that substantial level of muscle damage

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may occur after one-day of simulated competition. For instance, Takahashi, et al. (31)

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demonstrated an increase of 42% in CK after two consecutive sevens matches. In the present

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study, we showed an increase of 83% in the CK activity 15-h after three consecutive matches.

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In spite of the large increase in the CK activity reported herein, this increase is lower than

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those demonstrated by West, et al. (37) (250% and 500% of increase after the 1st and 2nd day

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of competition, respectively) and by Clarke, et al. (3) (126% of increase) after official

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tournaments, in male and female sevens players, respectively. Possibly, the higher CK values


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demonstrated by Clarke, et al. (3) are related to the fact that the athletes covered greater

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distances in sprinting than our players (13.5 m.min-1 vs. 10.5 m.min-1) (23). Additionally,

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these studies were performed during official tournaments, which probably induced higher

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physical engagement in specific playing actions (e.g., collisions), consequently entailing

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greater signs of muscle damage (23, 29, 32). In this regard, it is essential to further examine

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the physical/physiological differences between “friendly” and competitive rugby sevens

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matches.

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There was a moderate decrease of 5.7% in the SJ height, 4.8% in the CMJ height

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(non-significant) and a large decrease of 23% in the RFD100-200. This reduction in vertical

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jumping performance (SJ and CMJ) is in accordance with previous studies that demonstrated

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neuromuscular fatigue (i.e., measured by means of jump height) after professional rugby

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union (38), rugby league (21), and consecutive rugby sevens matches (37). Importantly, a

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previous study indicated that reductions in the RFD100-200 were highly associated with

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exercise-induce muscle damage and neuromuscular fatigue (24). Indeed, it has been shown

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that decreases in SJ height, CMJ height, and RFD100-200 (in association with increased levels

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of CK) might be related to significant impairments in the contractile machinery (24). From a

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physiological perspective, the decrement in the capacity to quickly apply/produce force and

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the symptoms associated with muscle damage and fatigue may be connected to the repetitive

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involvements in high-intensity efforts, such as collisions and maximum sprints during the

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matches (21, 22). Although the SJ and CMJ height have been shown to be highly associated

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with sprinting speed (16, 17), at least for this group of top-level rugby sevens players, the

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reductions in the vertical jumping performance were not accompanied by decreases in the

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maximal sprinting capacity. This suggests that the extent of muscle damage and fatigue

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induced in our sample was not able to affect/disturb the speed performance. On the other

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hand, the signs of muscle damage described here might compromise the ability of the players


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to perform maximally during the second day of competition, strongly indicating the necessity

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of implementing effective recovery methods during the transition from the first to the second

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day of competition during rugby sevens tournaments (6). This study presented some inherent limitations, listed as follows: 1) although players

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received similar meals and could ingest water ad libitum during the study duration, the exact

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composition of the food portions and the hydration status were not controlled; 2) the baseline

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physical tests on day 1 were performed in the afternoon, while the post-match tests on day 3

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were performed in the morning; 3) since circadian variations are expected in some physical

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performance indices (9, 25), our results could have been somewhat biased by this biological

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factor.

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In summary, the rugby sevens players were able to maintain the game movement

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patterns across three successive matches simulating the first day of a tournament. In addition,

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the increased levels of CK and the decreases in the SJ and RFD100-200 suggest that substantial

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levels of muscle damage and neuromuscular fatigue occurred in the day after the matches.

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This probably causes significant physical performance impairments on the second day of

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competition. Finally, additional studies are needed to comprehensively examine the efficacy

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of different recovery methods for restoring the physical and physiological traits of these elite

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athletes between successive matches or training sessions. Certainly, these applied approaches

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will positively influence the competitive performance of these players throughout the rugby

C

A

367

C EP

358

sevens’ tournaments.

368 369 370 371 372


16 373

PRACTICAL APPLICATIONS Sevens’ tournaments are typically executed over two consecutive days, with players

375

performing up to seven matches, interspersed with short recovery intervals (i.e., ≈3-4 h). After

376

examining the data collected in this study, it was revealed that these athletes could effectively

377

maintain the game movement patterns during three-successive sevens matches. However, on

378

the second day, they experienced meaningful signs of muscle damage and a compromised

379

capacity to produce explosive force (i.e., RFD). In this sense, coaches and scientists involved

380

in this sport are strongly encouraged to implement and create specific strategies able to

381

improve (and reduce the impairments) in the neuromuscular function of their athletes.

382

Intrinsically, training components such as plyometric and eccentric exercises may be optimal

383

alternatives to increase the “explosive muscle strength” (18) and enhance the protective effect

384

against muscle damage (19) in sevens players.

386

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491 492 493 494 495


21 496

FIGURE LEGENDS

497 498

Figure 1. Schematic illustration of the study design.

499

Figure 2. Comparisons between the 1st and 2nd halves for total distance covered and distance

501

covered in the different velocity ranges during the rugby sevens matches.

D

500

502

Figure 3. Comparison of the body load between the 1st and 2nd halves during the rugby sevens

504

matches.

A

C

C EP

TE

503


Table 1. Total distance (TD) and distance covered in different velocity ranges in the three rugby sevens matches.

Ranges

Match 1

Match 2

Match 3

M1 vs. M3

M2 vs. M3

ES (90% CI) - rating ES (90% CI) - rating ES (90% CI) - rating 470.1 ± 34.4

443.8 ± 32.2

393.9 ± 31.0*

6-12 km/h (m)

358.6 ± 43.8

415.3 ± 62.5*

325.6 ± 58.2#

12-14 km/h (m)

128.8 ± 16.0

153.5 ± 20.1*

143.2 ± 33.1

14-18 km/h (m)

234.9 ± 57.1

245.9 ± 58.6

18-20 km/h (m)

78.1 ± 25.6

69.3 ± 22.9

> 20 km/h (m)

182.5 ± 89.6

90.4 ± 36.8*

1453.2 ± 120.8

1417.0 ± 88.2

248.7 ± 45.7

93.0 ± 27.4

167.1 ± 59.6

C

A

-0.76 (-1.52; 0.01)

-2.22 (-3.17; -1.29)

-1.55 (-2.35; -0.68)

Moderate

Large

Large

1.29 (0.23; 1.79)

-0.75 (-1.37; 0.14)

-1.44 (-2.25; -0.60)

Large

Moderate

Large

1.54 (0.49; 2.11)

0.90 (-0.22; 1.28)

-0.51 (-1.10; 0.38)

Large

Moderate

Moderate

0.19 (-0.56; 0.92)

0.24 (-0.48; 0.99)

0.05 (-0.68; 0.79)

Trivial

Small

Trivial

-0.34 (-1.09; 0.39)

0.58 (-0.21; 1.29)

1.03 (0.13; 1.67)

Small

Moderate

Moderate

-1.03 (-2.21; -0.66)

-0.17 (-0.93; 0.54)

2.08 (0.65; 3.51)

Large

Trivial

Large

-0.30 (-1.07; 0.41)

-0.69 (-1.54; -0.01)

-0.53 (-1.28; 0.22)

Small

Moderate

Moderate

C EP

0-6 km/h (m)

TD (m)

M1 vs. M2

TE D

Velocity

1370.3 ± 79.9

Note - CI: confidence interval; ES: effect size; *different from match 1, P< 0.05; #different from match 2, P< 0.05.


Table 2. Comparison of the physical tests at baseline (pre) and after (post) three consecutive rugby sevens matches. Post

ES (90% CI) - rating

SJ (cm)

42.0 ± 4.4

39.6 ± 3.3*

-0.55 (-1.34; 0.16) Moderate

CMJ (cm)

41.1 ± 3.8

39.1 ± 3.4

-0.53 (-1.28; 0.22) Moderate

Sprinting 40 m (s)

5.0 ± 0.2

5.0 ± 0.2

0.14 (-0.60; 0.88) Trivial

RFD100 (N.ms-1)

730.0 ± 255.6

519.6 ± 180.1*

-0.82 (-1.68; -0.14) Large

RFD200 (N.ms-1)

1171.8 ± 345.4

859.3 ± 266.2*

-0.90 (-1.75; -0.19) Large

441.8 ± 89.8

339.7 ± 86.1*

-1.14 (-1.90; -0.32) Large

2949.3 ± 328.4

2821.6 ± 388.0

-0.39 (-1.08; 0.40) Small

RFD100-200 (N.ms-1) MIF (N)

TE D

Pre

Note - SJ: squat jump; CMJ: countermovement jump; RFD: rate of force development in 100

A C

C EP

ms, 200 ms, and 100-200 ms; MIF: maximum isometric force; *P< 0.05.


Table 3. Serum creatine kinase (CK) activity and cytokine concentration at baseline (pre) and 15-h post three consecutive rugby sevens matches. Pre

Post

ES (90% CI) - rating

CK (Units.l-1)

699.6 ± 451.0

1282.0 ± 532.2*

1.29 (0.34; 1.92) Large

IL-6 (pg.ml-1)

1.68 ± 0.86

1.59 ± 0.84

-0.10 (-0.84; 0.63) Trivial

TNFα (pg.ml-1)

1.14 ± 0.62

1.31 ± 0.57

0.27 (-0.47; 1.01) Small

4.79 ± 2.07

4.80 ± 2.14

0.01 (-0.73; 0.74) Trivial

-1

D

IL-10 (pg.ml )

A

C

C EP

TE

Note - IL-6: interleukin-6; IL-10: interleukin-10; TNFα: tumor necrosis factor - α; *P< 0.05.


D TE C EP C A Copyright ª 2017 National Strength and Conditioning Association

