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Effect of Maximal Aerobic Power on Match Performance in Elite Soccer Referees

The aim of this study was to verify whether referees' maximal aerobic power could influence competitive match exercise intensity. Eight elite-level referees (mean ± SD age, 37.6 ± 3.4 years) were each observed during 2 Serie A matches (n = 16), and the mean of each match activity was used for analysis. Match activities were monitored with encoderequipped cameras. Vo2max was assessed under field conditions with a portable device during a progressive multistage protocol. The Vo2max of each subject was expressed in absolute terms (Vo2 maxab, Lmin−1), relative terms (Vo2maxrel, mlkg−1min−1), and independent from body mass (Vo2 maxind, mlkg−0.75min−1). Significance was set at p ≤ 0.05 for all measurements. Total distance covered during the match correlated significantly with Vo2maxind (r = 0.77) and Vo2maxab (r = 0.87). Vo2maxind, Vo2maxrel, and Vo2maxab correlated negatively (p < 0.05) with the time spent standing still during the match (r = −0.90,-0.85, and-0.86, respectively, p < 0.05). During the first half of the match, referees with higher levels of Vo2maxrel (r = 0.93, p < 0.05) and Vo2maxind (r = 0.90, p < 0.05) were able to cover more distance at medium intensity. In the second half of the match, medium-intensity distance and low-intensity time correlated significantly (p < 0.05) with Vo2maxab (r = 0.76) and Vo2maxrel (r = 0.75), respectively. The results demonstrate the positive influence of Vo2max in determining both the total amount of distance covered and the exercise intensity during a game. Higher levels of Vo2max may provide referees the opportunity to be more active and herefore closer to the action on the field during the game.