The Worst Case Scenario: Locomotor and Collision Demands of the Longest Periods of Gameplay in Professional Rugby Union

Reardon C., Tobin D.P., Tierney P., Delahunt E.

Several studies have utilized global positioning systems (GPS) to examine positional differences in the physical demands of rugby union, both on average and during singular bouts. However, the ability to report quantitative data in these studies is hindered by a lack of validation of certain aspects of GPS micro-technology. Additionally, no study has analyzed the positional physical demands during the longest bouts of ball-in-play time in rugby union.

The aim of this present study is to compare the demands of the single longest period of ball-in-play, referred to as the “worst case scenario” (WCS), between positional groups, which have previously been noted to have distinguishable game demands. The results indicate that WCS periods follow a similar sporadic pattern as average demands but are played at a much higher pace than previously reported for average game demands, with an average meters per minute of 116.8 m.

Positional differences in running and collision activity previously reported are also observed within WCS periods. Backs covered greater total distances than forwards (318 m vs 289 m), engaged in more high-speed running (11.1 m/min vs 5.5 m/min), and achieved higher maximum velocities (MaxVel). Outside Backs achieved the highest MaxVel values (6.84 m/sec). Tight Five and Back Row forwards experienced significantly more collisions than Inside Backs and Outside Backs (0.73 & 0.89 collisions/min vs 0.28 & 0.41 collisions/min respectively).

These findings provide insights into the positional physical requirements during prolonged periods involving multiple high-intensity bursts of effort. While the current state of GPS micro-technology as a measurement tool does not allow reporting of collision intensity or acceleration data, the combined use of video and GPS offers valuable information to practitioners, aiding in matching and replicating game demands in training.