Maximum ball in play demands for sub-elite Rugby Union referees in domestic club rugby

Abstract

Purpose: Rugby union referee research has reported the game demands for whole game averages and comparisons between each half and 10 minute periods. No study has reported the movement game demands for the maximum ball in play time for referees. The purpose of this study was to quantify the maximum ball in play (Max BiP) demands termed “worst case scenario” (WCS) of sub-elite rugby union referees using 10Hz Global Positioning System (GPS) units. Method: Movement demands of ten (n=10) sub-elite referees across 27 matches, played during the 2017/18 All Ireland League Division 1, was calculated using 10Hz GPS units. The total distance covered (m), relative distance (m.min-1), percentage time in 6 velocity zones, were reported across the whole match, 1st half, 2nd half, 10minute periods and the maximum ball in play time using paired sample t-tests. Cohen’s d effect sizes was reported. Results: The maximum ball in play time was reported to be 172 ± 71 sec. The relative distance during Max BiP (107.9 ± 22.54 m.min-1) was significantly higher (p < 0.005) than whole match (75.1 ± 8.6 m.min-1) and 1st half (75.4 ± 8.7 m.min-1) & 2nd half (74.8 ± 13.1 m.min-1). During the Max BiP, referees spend a significantly higher (p < 0.005) percentage of time above whole game averages for walking (0.5 - 2.0m.s-1), jogging (2.01 - 4.0m.s-1), running (4.01 - 5.5m.s-1) and lower for high speed running (5.51 - 7.00 m.s-1) and sprinting (>7.01m.s-1). Conclusion: The results of this study quantifies the Max BiP movement demands for a sub-elite rugby union referee which are higher than those reported in whole game averages, 1st & 2nd halves and some 10min periods. These results provide sports scientists with the worst case scenario demands and can allow for these demands to be replicated in training with those experienced in matches.