Let me express it another way.

Think of 5 relevant attributes of your body for playing something well.

Guesstimate where they were on the population bell curve when you were 10.

Guesstimate if these would have been on a different spot on the population bell curve for that attribute when you were an adult. Would you have guessed it when you wee 10? Would others have guessed it about you at that age?

Puberty changes you in unpredictable ways. Do we need a study to know that?

Everyone committing to tennis before they are 10 are elite, you wouldn't do it otherwise. Who is the best player of that elite set changes given the great puberty shake up.