Are top athletes born or made

240,000 birthdays don't lie: December children fall through the mesh of sports sponsorship

The TagesWoche has analyzed over 240,000 athlete birth dates. The statistics clearly show that those who are born later in the year have less chance of being promoted in sport.

If you have your birthday at the end of the year, you have less chance of being promoted in sport. The name of the phenomenon: Relative Age Effect (RAE). The reason: Children who have their birthday late in the year are physically inferior to their classmates a few months older and are therefore less encouraged than the supposedly “more talented” premature babies.

Although the RAE has long been known in sports science and some theories promise relief, nothing about it seems to be changing. This is shown by the analysis of 240,000 athletes' birth dates during the day of the week. The deviation from the distribution in the average population is statistically significant with a confidence level of 99 percent.

The effect is particularly noticeable among the young elite squads in Swiss sport. This is hardly surprising, because the sooner supposedly talented children are separated from the apparently less talented, the stronger the RAE. Too often, the physical superiority of the premature babies seduces trainers into making a selection:

The data of the youth squad comes from the websites of the respective association or from the website of FC Basel - as of mid-March 2014. The data of the Swiss footballers comes from the website "", as of February 20, 2014.

But the REA can also be proven in adult sports. And even worldwide, as the analysis of 243,000 footballer birth dates that are listed on "" shows:

The data set includes all football players who were recorded on February 20, 2014 at “”. There are a total of 271,963 football players. The date of birth could be read out correctly for 243,112.

What is striking about this statistic is that the months of August and September are also strongly represented. This can be explained by the fact that in various countries such as Germany and Switzerland until 1997, the reference date for the change of year was not January 1st - but August 1st.

At that time, the August and September children benefited from the relative age effect. What is easy to see when the statistics are broken down by year of birth:

This in turn proves that the Relative Age Effect has nothing to do with the fact that those born in the last quarter of the year are less talented than those born early. "If you change the deadline, the effect just shifts," says Michael Romann, who scientifically studies the RAE for the Swiss Federal Sport University Magglingen.

There may be various reasons for the fact that the effect is more noticeable among young footballers (born in 1993 and younger) than among those born between 1980 and 1992.

On the one hand, the data allow the conclusion that in the junior academies the physical development of a junior has a very strong influence on the selection. On the other hand, the step from the offspring to the professionals usually takes place after the end of puberty.

The late-born, who have bitten through by then, no longer have any physical disadvantage. Yes, they could even have the advantage that as adolescents they made up for their physical disadvantages with technique and tactics, so that as adults they are the better footballers.

If only absolute top athletes are considered, then the RAE weakens. This is shown by a comparison of the months of birth broken down by market value. This comes from «», so it is a more or less precise estimate by laypeople.

Even with players with an estimated market value of over 5 million euros, the early months of birth are overrepresented, but less so than is the case for the population of all footballers.

Why December children are less encouraged - and what is being done about it in Swiss sport

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Help for December children: means against the relative age effect in theory and practice