I played various sports in my youth. At a young age in parks and rec leagues the best players on your team could either be boys or girls. But once you hit puberty and start playing in high school you notice the changes and abilities in those same people. Hell go to you local high school varsity boys and varsity girls basketball games and you will spot a difference across the board. Not even just a matter of height difference or shooting and jumping, but notice how quickly the girls will rack up fouls compared to the boys.