Background: Performance analysis in rugby union has become an integral part of the coaching process. Although performance analysis research in rugby and data collection has progressed, the utility of the insights is not well understood. The primary objective of this review is to consider the current state of performance analysis research in professional rugby union and consider the utility of common methods of analysing performance and the applicability of these methods within professional coaching practice. Methods: SPORTDiscus electronic database was searched for relevant articles published between 1 January 1997 and 7 March 2019. Professional, male 15-aside rugby union studies that included relevant data on tactical and performance evaluation, and statistical compilation of time-motion analysis were included. Studies were categorised based on the main focus and each study was reviewed by assessing a number of factors such as context, opposition analysis, competition and sample size. Results: Forty-one studies met the inclusion criteria. The majority of these studies measured performance through the collection and analysis of performance indicators. The majority did not provide context relating to multiple confounding factors such as field location, match location and opposition information. Twenty-nine performance indicators differentiated between successful match outcomes; however, only eight were commonly shared across some studies. Five studies considered rugby union as a dynamical system; however, these studies were limited in analysing lower or national-level competitions. Conclusions: The review highlighted the issues associated with assessing isolated measures of performance, lacking contextual information such as the opposition, match location, period within match and field location. A small number of studies have assessed rugby union performance through a dynamical systems lens, identifying successful characteristics in collective behaviour patterns in attacking phases. Performance analysis in international rugby union can be advanced by adopting these approaches in addition to methods currently adopted in other team sports.

Purpose: To examine changes in, and relationships between, sleep quality and quantity, salivary testosterone, salivary cortisol, testosterone-to-cortisol ratio (T:C), and self-reported muscle soreness during a residential-based training camp in elite rugby players. Methods: Nineteen male rugby players age 26.4 (3.9) years, height 186.0 (9.4) cm, and weight 104.1 (13.4) kg (mean [SD]) participated in this study. Wrist actigraphy devices were worn for 8 nights around a 4-d training camp (2 nights prior, during, and 2 nights after). Sleep-onset latency, sleep duration, sleep efficiency, and waking time were measured. Participants provided saliva samples during camp on waking and again 45 min later, which were then assayed for testosterone and cortisol levels. They also rated their general muscle soreness daily. Results: Little variation was observed for sleep quality and quantity or testosterone. However, significant differences were observed between and within days for cortisol, T:C, and muscle soreness (P < .001). Few relationships were observed for sleep and hormones; the strongest, an inverse relationship for sleep efficiency and T:C (r = −.372, P < .01). Conclusions: There may be no clear and useful relationship between sleep and hormone concentration in a short-term training camp context, and measures of sleep and testosterone and cortisol should be interpreted with caution because of individual variation. Alterations in hormone concentration, particularly cortisol, may be affected by other factors including anticipation of the day ahead. This study adds to our knowledge that changes in hormone concentration are individual and context specific.

We conclude that physical or psychosocial treatments may affect sal-T, sal-C and T:C; and individual variation in responses to treatments may exist.

Experiential knowledge of elite international coaches was investigated to reveal insights on successful rugby union strategies and tactics required to prevail in international competition. Three elite coaches who coached at a Rugby World Cup were interviewed using an in-depth, semi- structured approach. They were asked about specific strategies and tactics which they believed were required to be successful in an upcoming international tournament and a thematic analysis of qualitative data followed. Particular interest was paid to the influence of potential constraints and how these factors impact performance behaviours over time. The importance of an effective tactical kicking game in attacking strategies was highlighted, along with an adaptable defensive structure following a turnover. Unsuccessful performance behaviours in international rugby were reported to be connected with an irrational kicking game, a weak defensive line and losing possession off set-piece plays. These results support the need for a multidisciplinary approach, where exploring coaches’ knowledge presents an opportunity to enhance understanding across the performance analysis field. Further research is needed to complement experiential knowledge with quantitative research in rugby performance analysis.

The aim of this study was to compare the short-term performance of substitute players to starting players during International Rugby Union matches and determine how this performance was influenced by playing position, the timing of the substitution and the score margin between teams. Individual player performances (n = 298) for substitutes and the starters they replaced were observed across 17 matches played between tier 1 rugby nations. Performance was categorised as the total number of involvements, the number of attacking and defensive involvements, as well as the effectiveness of a player's performance for each of the above involvement categories. Results revealed forward substitutes performed more total ( p = 0.001, ES = 0.61), attacking ( p = 0.026, ES = 0.32) and defensive ( p = 0.023, ES = 0.31) involvements than forward starters; however, there were no differences found for backs ( p = 0.819–0.911). In addition, it was observed that an increase in score margin at the time of substitution led to a decrease in the total and attacking involvements per minute that a substitute performed, but an increase in defensive involvements for both forwards and backs. These findings provide a platform for coaches to make tactical decisions regarding substitution patterns during International Rugby matches. Specifically, coaches should prioritise forward substitutions over back substitutions, and implement tactical changes earlier in the second half to gain an advantage over the opposition.