Influence of physical and technical aspects on change of direction performance of rugby players: An exploratory study

We examined the relationships between change of direction (COD) speed and deficit, and a series of speed-and power-related measurements in national team rugby union players and analyzed the influence of movement patterns on COD ability. Eleven male athletes completed the following physical assessments on different days: day 1—anthropometric measurements, and lower-body kinematic parameters (assessed with eight inertial sensors) and completion time in COD tests (proagility, 45◦ cutting maneuver (CUT), and “L” (L-Drill)); day 2—bilateral and unilateral squat and countermovement jumps, 40 m linear sprint, and bar-power output in the jump squat and half-squat exercises. Pearson’s product–moment correlations were performed to determine the relationships between COD velocities, COD deficits, and the speed–power variables. Differences between players with higher and lower COD deficits were examined using magnitude-based inferences. Results showed that (1) greater sprint momentum was associated with higher COD deficits, particularly in drills with sharper angles and multiple directional changes (L-drill and pro-agility); (2) higher unilateral jump heights were associated with greater COD deficits in the pro-agility and L-drill but not in the CUT; (3) faster athletes were less efficient at changing direction and presented greater trunk and knee flexion angles during COD maneuvers, probably as a consequence of higher inertia

Change of direction deficit in national team rugby union players: is there an Influence of playing position?

The aim of this study was to investigate the change of direction (COD) ability and deficits of elite rugby union players, discriminating between position (backs and forwards), and between "faster and slower players", in multiple COD tasks. Twenty-four male rugby union players from the Brazilian senior National team completed the following assessments: Squat and countermovement jumps; drop jump; standing long jump, horizontal triple jumps; 40-m linear sprint; Pro-agility, L-Drill, and Zig-zag COD tests; and squat 1-repetition maximum. The differences between backs and forwards and between faster and slower performers were examined using magnitude-based inferences. Backs were faster (in both linear and COD speed tests) and jumped higher than forwards. Moreover, they generated an inferior sprint momentum. No differences were found in COD deficit between playing positions. However, when dividing the sample by median split, faster players outperformed their slower counterparts in all power⁻speed variables and presented higher COD deficits. These results suggest that separating rugby players by playing position might not discriminate players with different COD skills and that the median split analysis is more sensitive to identifying these differences. Furthermore, the present data indicate that faster rugby players are less efficient at changing direction and tolerating higher approach velocities in COD maneuvers

The Role of Velocity Based Training in the Strength Periodization for Modern Athletes

Resistance training (RT) is considered the most important method to improve the athlete’s strength and rate of force development (RFD). In the last decade, the importance of monitoring velocity during RT has drastically grown, because of an increased availability of linear position transducers (LPT) and inertial measurement units (IMU). The purpose of this review is to analyze the existing literature on testing techniques and performance strategies used to enhance strength and power performance of elite athletes, by monitoring the velocity of resistance training. The authors focus in particular on the level of effort of resistance training defined by velocity; how the loss of velocity correlates with the degree of fatigue and how it can be used to enhance the performance of competitive athletes; the use of LPT as part of the daily routine of the strength and conditioning programs in competitive sport. It is therefore critical for the sports scientists to have a correct understanding of the basic concepts of the velocity-based training and their application to elite sports. The ultimate goal is to give some indications on the velocity-based resistance training integration in the programs of different sports in the high performance environment

Force-Velocity Relationship in three Different Variations of Prone Row Exercises

This study examined the force-velocity relationship and tested the possibility of determining the relative loading intensity (% 1RM) in three different variations of prone row exercises. Thirty male top-level athletes from two different sports (National Team rugby union players and professional mixed martial arts fighters) were submitted to maximum dynamic strength assessments in the free prone bench pull, bent over barbell row, and bent over Smith-machine row, following standard procedures encompassing lifts performed from 40 to 100% of 1RM. The mean velocity, mean propulsive velocity, and peak velocity were measured in all attempts. Linear regression analyses were performed to establish the relationships between the different measures of bar-velocities and %1RM. The actual (obtained during the assessments) and predicted 1RM values (based on the predictive equations) for each exercise were compared using a paired t-test. In all exercises, the predicted 1RM scores - based on all velocity variables- were not different from their respective actual values. The close linear relationships between bar-velocities and distinct %1RM (coefficient of determination ≥ 80%, in all experimental conditions) allow precise determination of relative load and maximum dynamic strength, and enable coaches and sports scientists to use the different velocity outputs to rapidly and accurately monitor their athletes on a daily basis

Influence of congested match schedules, pre-match well-being and level of opponents on match loads during World Rugby Women's Sevens series

This study aimed at assessing (1) the effect of congested match schedules on match loads and well-being as well as (2) pre-match well-being and level of opponents on match loads in elite women's rugby sevens. Eleven players of the Brazilian women's rugby sevens national team were investigated across three 2019-20 HSVC World Rugby Women's Seven Series tournaments to assess: (1) within-tournament match-to-match changes in various external and internal match load measures; (2) daily changes in players' well-being collected before the commencement of a tournament (day one) and during or post-tournament (day two to day four); and (3) the effect of pre-match well-being and level of opponents (high vs. low level) on match loads. Results revealed no between-match significant differences (p > 0.05) in most of the investigated match load measures. A congested match schedule negatively affected perceived fatigue (p 0.05). These results highlighted the necessity to embrace a multidimensional approach when adopting monitoring systems in elite women's rugby sevens during tournaments and to consider various contextual factors possibly affecting match loads, besides those investigated

Bilateral Microphthalmia with Optic Nerve Hypoplasia and Achiasmia

A 15-year-old boy underwent neurological and ophthalmological evaluation. At birth, a severe bilateral microphthalmia, micropenis, and scrotal hypoplasia were diagnosed. Ophthalmologic examination showed right anophthalmia and severe left microphthalmia. Radiological examination showed normal orbital and skull structures. Magnetic resonance imaging (MRI), revealed the absence of the right eye, left microphthalmia, optic nerve hypoplasia, aplasia of the optic chiasm, and tracts. Audiometric examination and electroencephalogram were normal. There was no mental retardation. The chromosomal examination was normal. The patient is examination was also negative for any type of known risk factor