Accelerations and high intensity running in field and assistant football referees during match play

Abstract

ABSTRACTObjectives: (1) to examine accelerations and high intensity running (HIR) in football field referees (FR) and assistant referees (AR) during football matches and (2) to evaluate fluctuations in accelerations and HIR between first and second half and in 5-min periods.Methods: All movements of the referees were measured using a radio-based tracking system during 41 matches in the Norwegian top and second league during the 2015 and the 2016 seasons. Movements were classified into accelerations (≥2 m · s–2) and HIR (≥19.8 km · h–1).Results: AR performed 86% more accelerations than FR (158 (147–169) vs. 85 (76–94), P < 0.001, d = 1.9), and FR performed 171% longer HIR distance than AR (619 (534–703) m vs. 228 (208–248), P < 0.001, d = 2.7). When divided into 5-min periods, the number of accelerations (P < 0.001) and acceleration distance (P < 0.001) were reduced towards the end of both halves in AR. However, in the 5-min subsequent to the most intense 5-min period of the match, both FR and AR performed accelerations and HIR (n and m) equal to the 5-min mean (P > 0.35).Conclusions: As the running performance of FR and AR are substantially different, training recommendations for AR should include more accelerations while FR should focus on HIR and endurance training.