The principle suggests that older teams are automatically more likely to win, with the Potters working on research to compensate for that.
Stoke City recently became the first known British football club to formally trial new research into eradicating the concept of birth bias in the game.— Stoke City FC (@stokecity) May 3, 2018
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In junior football, players in the same age group/school year could have as many as 10 or 11 months between them, a huge difference in physical development. One Under-10 team could therefore actually be much older than another Under-10 team, for example.
A report on the club's official website explains how they mixed players from Under-9 and Under-10 age groups, as well as Under-11 and Under-12, to create equal age seven-a-side teams.
The work has been carried out in conjunction with the Cruyff Institute, Bath University and the Premier League and has the potential to revolutionise the way that young players in England are grouped and coached.
"The idea behind the tournament evolved around recent research from the Cruyff Institute which found that the older the average age of a team, the more likely they are to come out on top in matches," Paul White, Academy Head of Sports Science and Athletic Development, said.
"From the coaches' side of things they were able to look at players in different situations, such as younger lads competing alongside older players and the psychological challenges for both.
"The younger ones may have been apprehensive about the challenge of mixing with more senior players, while the older ones may take on more of a leadership role so it's good to expose them to that.
"The feedback we have received from the players has been positive, both from a playing point of view and mixing with their fellow peers from either older or young age groups. They've told us how they felt they had learnt more from this tournament than in their normal games which from a long-term player development point of view is great."
This is just the start and Stoke are keen to continue the research by holding more mixed age training sessions and tournaments - the next will be in summer. The next step will also be to go further and try mixing from Under-9 right the way through to Under-12 to see what effect it has.
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