Activity profile and physical demands of football referees and assistant referees in international games

Abstract

Time-motion analyses and physiological measurements were performed to investigate the physiological demands of football referees (n = 15) and assistant referees (n = 15) in international games and to examine whether high-intensity running (HIR) correlates to the referees' ability to keep up with play. Total distance covered (10.27 ± 0.90 vs. 6.76 ± 0.83 km) and HIR (1.92 ± 0.58 vs. 0.97 ± 0.22 km) was higher (P < 0.05) for referees than assistant referees, while sprinting distance was not different. Referees covered 0.89 ± 0.37 km by backwards running and assistant referees covered 1.54 ± 0.66 km by sideways running. Mean heart rate was higher (P < 0.05) for referees than assistant referees (150 ± 3 vs. 123 ± 3 b.p.m.), whereas blood lactate was not different. Backwards/sideways running decreased (P < 0.05) from the first to the last 15-min period for referees (49%) and assistant referees (42%), whereas HIR was unaltered. HIR was inversely correlated with the five highest distances from infringements in both halves (r = −0.60 and −0.58, P < 0.05). In conclusion, international match officials carry out an important amount of HIR throughout games, while low-intensity and unorthodox running activities are reduced during games. Referees performing the most high-intensity work are better to keep up with play. The match activities differ significantly between referees and assistant referees, which should be considered in training and testing procedures.

Keywords:

• Time-motion analysis
• high-intensity running
• heart rate
• blood lactate
• distance from infringements

Acknowledgements

This study was supported by Danish Football Association and the European Football Association, UEFA. We would like to thank the match officials involved in the study for their committed participation. We would also like to acknowledge the great effort of Per Hansen, Jan Malm-Hansen, Mihai Ursta Relu, Jorge Perez-Gomez, Mads Bendixen, Rasmus Bischoff, Thomas Gunnarsson, Therese Hornstrup, Karina Thomsen and Lena Varntoft in filming the referees. Practical assistance and much good advice were provided by the Referee Committee of the Danish Football Association.