Abstract

The aim of this paper is to assess whether the relative age effect is produced in professional football in Spain, reserve teams and lower age groups, where the current age cut-off for the formation of the different categories is the calendar year. The analysis included all players of the Spanish First Division in the 2009-2010 season, as well as 16 reserve and youth teams of 11 of these teams (total N=2116). The result of our study confirms the relative age effect in all groups, with a significant drop from lower age groups to reserve teams and the first division. It shows that systems for competition and talent identification need to be revamped in order to avoid this bias that limits the possibilities of athletes born in the last months of the year.