The Use of Global Positioning and Accelerometer Systems in Age-Grade and Senior Rugby Union: A Systematic Review

Energy expenditure of international female rugby union players during a major international tournament: a doubly labelled water study

The purpose of this study was to quantify the total energy expenditure (TEE) of international female rugby union players. Fifteen players were assessed over 14 days throughout an international multi-game tournament, which represented two consecutive one-match microcycles. Resting metabolic rate (RMR) and TEE were assessed by indirect calorimetry and doubly labelled water, respectively. Physical activity level (PAL) was estimated (TEE:RMR). Mean RMR, TEE, and PAL were 6.60 ± 0.93 MJ·day-1 (1578 ± 223 kcal·day-1), 13.51 ± 2.28 MJ·day-1 (3229 ± 545 kcal·day-1), and 2.0 ± 0.3 AU, respectively. There was no difference in TEE (13.74 ± 2.31 (3284 ± 554 kcal·day-1) vs. 13.92 ± 2.10 MJ·day-1 (3327 ± 502 kcal·day-1); p = 0.754), or PAL (2.06 ± 0.26 AU vs. 2.09 ± 0.23 AU; p = 0.735) across microcycles, despite substantial decreases in training load (total distance: -8088 m, collisions: -20 n, training duration: -252 min). After correcting for body composition, there was no difference in TEE (13.80 ± 1.74 (3298 ± 416 adj. kcal·day-1) vs. 13.16 ± 1.97 (3145 ± 471 adj. kcal·day-1) adj. MJ·day-1, p = 0.190), RMR (6.49 ± 0.81 (1551 ± 194 adj. kcal·day-1) vs. 6.73 ± 0.83 (1609 ± 198 adj. kcal·day-1) adj. MJ·day-1, p = 0.633) or PAL (2.15 ± 0.14 vs. 1.87 ± 0.26 AU, p = 0.090) between forwards and backs. For an injured participant (n = 1), TEE reduced by 1.7 MJ·day-1 (-401 kcal·day-1) from pre-injury. For participants with illness (n = 3), TEE was similar to pre-illness (+0.49 MJ·day-1 (+117 kcal·day-1)). The energy requirements of international female rugby players were consistent across one-match microcycles. Forwards and backs had similar adjusted energy requirements. These findings are critical to inform the dietary guidance provided to female rugby players.

Individual In-Situ GPS-Derived Acceleration-Speed Profiling: Toward Automatization and Refinement in Male Professional Rugby Union Players

BACKGROUND

Recently a proof-of-concept was proposed to derive the soccer players' individual in-situ acceleration-speed (AS) profile from global positioning system (GPS) data collected over several sessions and games. The present study aimed to propose an automatized method of individual GPS-derived in-situ AS profiling in a professional rugby union setting.

METHOD

AS profiles of forty-nine male professional rugby union players representing 61.5 million positions, from which acceleration was derived from speed during 51 training sessions and 11 official games, were analyzed. A density-based clustering algorithm was applied to identify outlier points. Multiple AS linear relationships were modeled for each player and session, generating numerous theoretical maximal acceleration (A0), theoretical maximal running speed (S0) and AS slope (ASslope, i.e., overall orientation of the AS profile). Each average provides information on the most relevant value while the standard deviation denotes the method accuracy. In order to assess the reliability of the AS profile within the data collection period, data were compared over two 2-week phases by the inter-class correlation coefficient. A0 and S0 between positions and type of sessions (trainings and games) were compared using ANOVA and post hoc tests when the significant threshold had been reached.

RESULTS

All AS individual profiles show linear trends with high coefficient of determination (r2 > 0.81). Good reliability (Inter-class Correlation Coefficient ranging from 0.92 to 0.72) was observed between AS profiles, when determined 2 weeks apart for each player. AS profiles depend on players' positions, types of training and games. Training and games data highlight that highest A0 are obtained during games, while greatest S0 are attained during speed sessions.

CONCLUSIONS

This study provides individual in-situ GPS-derived AS profiles with automatization capability. The method calculates an error of measurement for A0 and S0, of paramount importance in order to improve their daily use. The AS profile differences between training, games and playing positions open several perspectives for performance testing, training monitoring, injury prevention and return-to-sport sequences in professional rugby union, with possible transferability to other sprint-based sports.

KEY POINTS

AS profiles computed from rugby union GPS data provide positional benchmarks during training and competition. This study provides automatic detection of atypical data and the computation of error measurement of theoretical maximal acceleration and speed components. This refinement constitutes a step forward for a daily use of ecological data by considering data collection and method reliabilities. This easy-to-implement approach may facilitate its use to the performance management process (talent identification, training monitoring and individualization, return-to-sport).

Calf muscle abilities are related to sprint performance in male Rugby Union players

OBJECTIVES

To examine the strength of the relationship between plantarflexor power and strength-endurance metrics and 10-m sprint times in male Rugby Union players. A secondary aim was to examine the strength of the relationship within calf muscle metrics.

DESIGN

Observational cross-sectional correlational.

SETTING

Field-based.

PARTICIPANTS

Sixteen male Rugby Union players in the National Provincial Championship.

MAIN OUTCOME MEASURES

Participants completed three single-leg calf muscle tests: bodyweight power, weighted power, and strength-endurance. Data were recorded using the Calf Raise application. Three-to-four days later, average and best 10-m sprint performances were collected using timing lights.

RESULTS

There were large significant correlations between 10-m sprint performances (average and best times) and calf muscle power (weighted) and strength-endurance (total displacement and work) metrics (r = -0.503 to -0.628). There were large significant correlations between bodyweight and weighted power, weighted power and strength-endurance (total displacement and work), and most strength-endurance metrics (r = 0.520 to 0.943).

CONCLUSIONS

Our findings emphasise the importance of triceps surae muscle power and strength-endurance for maximal-effort accelerations and sprint performances in Rugby Union. Our data indicate that weighted power and total work from strength-endurance tests are the most useful metrics for further investigation in the context of short sprints and acceleration.

Physical Match Demands of International Women's Rugby Union: A Three-Year Longitudinal Analysis of a Team Competing in The Women's Six Nations Championship

There is a paucity of studies describing the physical match demands of elite international women's rugby union, which limits coaches' ability to effectively prepare players for the physical demands required to compete at the elite level. Global positioning system technologies were used to measure the physical match demands of 53 international female rugby union players during three consecutive Women's Six Nations Championships (2020-2022), resulting in 260 individual match performances. Mixed-linear modelling was used to investigate differences in physical match demands between positions. Significant effects (p < 0.05) of the position were observed for all variables, with the exception of relative distances (m.min^-1) at velocities of 1.01-3.00 m·s^-1 (p = 0.094) and 3.01-5.00 m·s^-1 (p = 0.216). This study provides valuable data on the physical match demands of elite international women's rugby union match play that may aid practitioners in the physical preparation of players to compete at this level. Training methodologies for elite-level female rugby union players should consider the unique demands across positional groups with specific considerations of high-velocity running and collision frequency.

Normative isometric plantarflexion strength values for professional level, male rugby union athletes

OBJECTIVES

The primary aim was to establish normative values of isometric plantarflexor muscle strength in professional male rugby union players and compare forwards with backs. The secondary aims were to examine how individual playing position or age influences isometric plantarflexor strength.

DESIGN

Cross-sectional.

SETTING

Testing at professional rugby clubs.

PARTICIPANTS

355 players (201 forwards and 154 backs) from 9 clubs in the English Premiership club competition.

MAIN OUTCOME MEASURES

Maximal unilateral isometric plantarflexion strength was measured, using a Fysiometer C-Station, in a seated position with a flexed knee and in maximal available dorsiflexion. Values are reported normalised to body mass and specific to playing position.

RESULTS

Mean combined limb isometric plantarflexion strength for the group was 193.1 kg (SD 32) or 1.86 xBW. (SD 0.31). Forwards were significantly weaker than backs (forwards = 1.75xBW (SD 0.26), backs = 2.00xBW (SD 0.28) (p=<0.0001)). Age category revealed no influence on plantarflexor strength.

CONCLUSION

This study presents normative isometric plantarflexion strength values for professional male rugby union players. Forwards are typically relatively weaker than backs.

Running demands in club, regional, national, and international provincial New Zealand rugby union competitions

The demands of national and international professional rugby union matches are well established, however, there has not been a comparative study investigating running demands in New Zealand teams playing in club (amateur), Heartland Championship (semi-professional Div 2), the Mitre 10 Cup (semi-professional Div 1) or Super Rugby (professional) competitions. This information could enable specific training and rehabilitation that programmes to be developed to meet the needs of players in the different competitions. Players wore 10 Hz GPS units during games for one rugby season to determine absolute (m) and relative (m.min^-1) measures for total distance, running volume (∼≥7 km·h^-1) and high intensity running (∼≥16 km·h^-1). There were typically minimal differences (1-2 m.min^-1) in running distance measures between amateur level front row forwards and inside backs compared to players in these positions at higher levels of competition. Therefore, amateur players in these positions may find the transition to higher competitions less challenging with respect to running load. In contrast, amateur outside backs and back row forwards may find the increased pace of higher levels of competition more challenging due to typically covering significantly less running and high intensity running distances in amateur games. Differences for half backs were more variable between the levels of competition. Based on our results, it cannot be assumed that amateur rugby has lower running demands than higher competitions or that there is a continuum of increased running demands with increasing competition levels, as some playing positions in the semi-professional (Div 2) (second lowest level of competition) team recorded the largest values for total distance, running and high intensity running. Therefore, the specificity of running demands in a position and competition need to be considered individually for each player when transitioning between competitions. The practice and perception of returning a professional player to amateur club rugby due to the belief that running loads being lower may also be flawed, as we found considerable positional variation in running demands within-and-between competitions.