USA Swimming provides Indiana university performance differences between male and female childhood athletes!

USA Swimming contributes to an athletic gender study that may be potentially groundbreaking.

From Science Daily:

The study analyzed data provided by USA Swimming that consisted of the best 50-yard freestyle performances for all USA Swimming-registered male and female swimmers ages 6 to 19 who competed from 2005 to 2010. This included 1.9 million swims. 

The study found no difference in swim performance in children younger than 8. It also found little difference in 11-and-12-year-olds.

[Link]

This suggests to me that male/female results within the preadolescent age groups do not have to be gender specific. I wonder what the positive or negative consequences would be if that was attempted?