Moreno Pérez, VíctorMartín Sánchez, María LuisaCoso Garrigos, Juan delFelipe Hernández, José LuisCourel Ibáñez, JavierSánchez Sánchez, Javier2023-05-282023-05-282021Moreno-Pérez, V., Martín-Sánchez, M. L., Coso, J., Felipe, J. L., Courel-Ibáñez, J., & Sánchez-Sánchez, J. (2021). Impact of COVID-19 lockdown on match activity and physical performance in professional football referees. Biology of Sport, 38(4), 761–765. https://doi.org/10.5114/biolsport.2021.1094510860-021X2083-1862http://hdl.handle.net/11268/12067o investigate the effect of COVID-19 lockdown on match-play metrics in professional football referees during official matches of the Spanish professional leagues. Forty-two professional football referees from the First (n = 20) and Second Division (n = 22) were monitored during 564 official games using Global Positioning System (GPS) technology. Data of matches before lockdown were compared to matches after resumption of the competition. Compared to pre-lockdown, in the referees of the First Division there was a decrease in the total running distance and the distance covered at all speed thresholds > 6 km · h-1 after lockdown (P < .05). In the Second Division referees, the post-lockdown measurement only showed a decrease in the running distance at 21-24 km · h-1 (P < .05), with no changes in the other speed thresholds. The post-lockdown measurement showed an increased distance covered at < 6 km · h-1 and the number of accelerations for both First and Second Division referees (P < .05). Referees' match activity was reduced due to the COVID-19 lockdown, while the effect on running parameters was more pronounced in First Division referees.engAcondicionamiento físico humanoFútboljournal article10.5114/biolsport.2021.109451open accessDeportePandemia