The engagement processes tested
| Full (short) Name | 1. Crouch-touch-pause-engage (CTPE) |
| Timing | Crouch (t=−5.2 s); touch (t=−2.9 s); pause (t=−1.2 s); engage (t=0.0 s) |
| Full description | The forward packs set up according to their normal current practice. Following an engagement call sequence of ‘crouch-touch-pause-engage’ the forward packs engaged with each other and held a short-duration sustained shove. This technique was regarded as the baseline condition for data analysis as it best represented current scrummaging practice and law when the engagement techniques were defined (May 2012) |
| Full (short) Name | 2. Crouch-touch-set (CTS) |
| Timing | Crouch (t=−4.0 s); touch (t=−1.7 s); set (t=0.0 s) |
| Full description | Same as baseline CTPE except the vocal commands removed the ‘pause’ so that this was non-verbal and the final command was changed from ‘engage’ to ‘set’ to reflect the scrum law amendment trials introduced globally by the IRB from September 2012 |
| Full (short) Name | 3. CTS with PreBind (PreBind) |
| Timing | Crouch (t=−4.0 s); Touch (t=−1.70 s); Set (t=0.0 s) |
| Full description | The forward packs set up according to their normal current practice in terms of binding and body positions but the coach had previously instructed the two forward packs to reduce their spacing sufficient to allow the subsequent actions while maintaining balance. The scrum followed an engagement call sequence of ‘crouch-touch-set’. On the ‘crouch’ players moved into their normal crouched posture. On ‘touch’ all four props moved their outside arms forward to take a bind on their opposition's body past the point of their shoulder, on their back or side. The LH props moved their left arm inside the right arm of the TH prop and gripped the TH prop's jersey on the back or side. The TH props moved their right arm outside the left upper arm of the opposing LH prop and gripped the LH prop's jersey with the right hand only on the back or side. The props were instructed not to grip the opponent's chest, arm, sleeve or collar. This loose bind was retained and the arm was not retracted. The ‘set’ command was an instruction to allow the two front rows to engage and then start a short-duration sustained shove |
For all the techniques the coach/referee checked for reasonable distance between packs at set-up and all players simulated competitive scrummaging attempting to adhere to Law (IRB, Law 20). All scrums aimed for an ‘engage and sustained pressure’ type scrum, involving initial engagement phase followed by a 4 s sustained push.
LH, loose head; TH, tight head.