The Relative Age Effect in German Elite Youth Soccer: Implications for a Successful Career.

Abstract

To investigate whether anthropometric profiles and fitness measures vary according to birth-date distribution in the German national youth soccer teams and to analyze whether there is a difference in the chance of becoming a professional soccer player depending on birth quarter (BQ). First, 554 players were divided into 6 age groups (U16-U21), each subdivided into 4 BQs. Every player performed at least one 30-m sprint, a countermovement jump, and an incremental test to determine individual anaerobic threshold. For players performing more than 1 test within a team, the best 1 was included. Since some players were part of several different teams, a total of 832 data sets from 495 individual soccer players, all born from 1987 to 1995, divided into 6 age categories (U16-U21) were included. Overall, more players were born in BQ1 than in all other BQs (P < .05). No significant difference between BQs could be observed in any anthropometric or performance characteristics (P > .18). Players born in BQ4 were more likely to become professional than those born in BQ1 (odds ratio 3.04, confidence limits 1.53-6.06). A relative age effect exists in elite German youth soccer, but it is not explained by an advantage in anthropometric or performance-related parameters. Younger players selected into national teams have a greater chance to become professionals later in their career.