RUCK PLAY IN RUGBY UNION Keane WHEELER email: email@example.com INTRODUCTION The ruck contest provides an essential means to win and retain possession of the ball in rugby union. A ruck occurs when an attacking ball carrier is tackled and there is at least one player from each team in physical contact, on their feet and around the ball (2). Research in rugby union has shown that players (especially forwards) spend considerable periods of game time competing for the ball in the ruck (1). In addition, improved rates of ball retention at the ruck has be shown to occur when attacking ball carriers exhibit low body height in the tackle and then the support players provide decisive clean out actions in the ruck contest (3). Beyond this, there is a lack of scientific research describing ruck play in rugby union and particularly examining the attacking strategies that affect the outcome of the ruck contest. This study used performance analysis to examine factors associated with successful ball retention during the ruck contest in rugby union. The specific objectives included: 1. Determine the interaction between the number of players at the ruck and ball retention. 2. Determine the relationship between ball clearance times and ball retention at the ruck. METHODS
Performance analysis was conducted on 12 international rugby union games and focused on the phase leading up to and including the ruck contest (N = 1260).
The primary variables consisted:
Number of attackers and defenders at the ruck
Ball clearance times from the ruck
Retention of the ball at the ruck
Kappa measurements determined a high intra-tester reliability for coding. ANOVA examined the relationship between the ratio of players at the ruck and retention of the ball. Chi-squared ( χ 2 ) association analysis then examined the relationship between the players and ball retention and clearance times.
RESULTS Analysis showed a significant relationship between the ratio of attackers to defenders and the outcome of the ruck (F (4,1256) = 14.172, p < .001). A ratio of two attackers to every defender was associated with retaining possession of the ball at the ruck (2.08 ± 1.03, N = 1133 ). In contrast, a higher ratio of defenders was associated with the attacking team loosing possession of the ball at the ruck (1.28 ± 0.87, N = 57) or the attacking team being penalised (1.36 ± 0.66, N = 34). Further analysis showed that teams committing one attacker to the ruck contest were likely to loose possession of the ball (χ 2 (6) = 21.168, p = .002) (Figure 1) . Similarly, the attacking team was likely to loose the ball at the ruck when there was 4 or more defenders committed to the contest (χ 2 (9) = 114.798, p < .001). It was shown that 33.3% of ruck turnovers occurred with 4 or more defenders committed to the contest (SR = 7.1, N = 11). Figure 1: Number of attackers when possession of the ball was lost at the ruck . Analysis of the time it took to recycle possession at the ruck demonstrated that attacking teams were more likely to loose the ball at the ruck with greater ball clearance times (χ 2 (3) = 84.015, p < .001). It was shown that 94.8 % of ruck turnovers occurred when the ball clearance time was beyond 3.5 s (SR = 7.0, N = 55). Analysis then showed a significant relationship between a greater number of defenders committed to the ruck and slower ball clearance times (r = .42, p < .001). It was then observed that committing two or more defenders at the ruck promoted slower ball clearance times (χ 2 (9) = 154.58, p < .001). Similarly, committing greater than two attackers at the ruck was found to promote slower ball clearance times (χ 2 (6) = 198.79, p < .001). REFERENCES 1. Docherty, D., et al. J. Human Movement Studies . 14:269-277, 1988. 2. IRB. The laws of the game. 2003. 3. McKenzie, A., et al. J. Human Movement Studies . 17:101-113, 1989. CONCLUSION The ruck contest is essential to win and retain possession of the ball in rugby union. The findings of the current study suggest that attacking teams should aim to quickly recycle possession (ball clearance times less than 3.5 s) at the ruck contest in order to maintain possession of the ball. To achieve faster ball clearance times at the ruck, attacking teams need to commit fewer supporting players to the contest. However, the attacking team will have a higher chance of loosing the ball if too few players are committed to the ruck. In attack, this study showed that a ratio of two attackers for every defender at the ruck contest increased rates of ball retention. Conversely, this study demonstrated that defensive teams should commit greater numbers to the ruck contest in order to slow ball clearance times of their opponents. This will promote a greater number of turnovers for the defensive team. In addition, slower ruck clearances would no doubt allow the defensive team to realign their players for subsequent attacking phases of play when the ball was not turned over at the contest. It should be noted that a trade-off exists where defensive teams have a higher chance of being penalised when committing a greater number of defenders attempting to slow the ruck contest. This study demonstrated that an even ratio of attackers to defenders meant that turnovers were likely without the defensive increasing the chance of being penalised. The findings of this study can be used to design appropriate assessment procedures and training programs to enhance ruck play in rugby union.