Title:
An evaluation of the external validity and reliability of a rugby league match simulation protocol.

Abstract:
The aim of this study was to assess the external validity and reliability of a novel rugby league match simulation protocol. With ethical approval, 16 males (age 22.4 ± 7.1 years, estimated (·)VO(2max) 52.1 ± 4.5 ml · kg⁻¹ · min⁻¹) performed the rugby league match simulation protocol on two occasions 10 to 14 days apart. During the rugby league match simulation protocol participants covered a total distance of 8,444 ± 212 m, at an overall locomotive rate of 97.3 ± 2.5 m · min⁻¹. In addition, changes in very high (-22.4%), high (-8.6%) and low intensity (1.6%) running locomotive rates from the first to the fourth quarter were observed. The magnitude of these movement characteristics did not differ significantly (P > 0.05) between repeated trials, with coefficients of variation of 1.1, 4.2 and 10.6%, and 95% limits of agreement of -0.4 ± 4.0, -0.3 ± 3.6, and -0.2 ± 4.4 m · min⁻¹ for overall, high and very high intensity running locomotive rates, respectively. On this evidence, the rugby league match simulation protocol replicates the movement demands observed during elite rugby league matches. Furthermore, the protocol can be performed reliably amongst non-elite sports players and thereby has the potential to be used as a tool for monitoring the effectiveness of various interventions on physical match performance.