I was working with an 8 year old yesterday. Developing rhythm and a stable base from which he can eventually drive up with his legs on the serve. Federer commented yesterday after beating Ferrer in the ATP World Tour Finals:
'I definitely needed a good second serve, especially in the first set. I didn't have that may serves in play the way I wanted to - either the rhythm was off a bit or I wasn't pushing enough with the legs..."
There tends to be an assumption that the top players are doing something extra special? Nope, not at all, it's the same challenges, just at a different level!