On-field movements, heart rate responses and perceived exertion of lead referees in Rugby World Cup matches, 2019.

OBJECTIVES

Quantify the on-field movements, heart rate and perceived exertion (RPE) of lead referees during Rugby World Cup matches.

DESIGN

Descriptive, observational.

METHODS

On-field movements (distance, average speed, high-speed running [>5ms]), heart rate and RPE of 11 lead referees were assessed during 29 Rugby World Cup (Knockout and Pool) matches. Average speed and heart rate were assessed using rolling average methods (1-10min epochs). Linear mixed models and Cohen's effect size (d) were used to compare match variables between Pool and Knockout matches.

RESULTS

Referees covered on average 6674±566m (65.8±6.3mmin), with 586±290m in high-speed running. Mean heart rate was 146±9 beatsmin, summated-heart-rate-zones was 235±36AU, and sRPE load was 577±205AU. A large reduction (d=1.40) in high-speed running distance and moderate reductions in average speed over 1 (d=0.81) and 2min (d=0.83) epochs were found during Knockout, compared to Pool matches. Differences between Pool and Knockout matches on other measures of referee movement, heart rate and RPE were trivial.

CONCLUSIONS

This is the first investigation to examine the effect of competition stage on rugby union referees on-field performance. Individual and match contextual factors may explain the reduction in high-speed running during Knockout matches, however more detailed examination of the factors influencing referee performance is required for greater insight into the key performance indicators in rugby union. Nonetheless, these data provide practitioners with knowledge to assist in preparation of rugby union referees for future Rugby World Cup competitions.