Football does not require 10 hours a day of training. Even pro players train just a couple of hours per day, with maybe an extra hour of tactical work. In fact, you'd struggle to find any physical sport that requires that much dedication, because overtraining is very dangerous. I knew a few teenagers in professional basketball teams and whenever they were seen around playgrounds they were soundly rapped by their coach. The only exception is pre-season conditioning, but even then you will not get anywhere near 8 hours, let alone 10.

(aside: several retired players alleged that there are loads of unreported cases of depression among top-flight pros, mostly due to the fact that they simply don't know what to do with most of their time.)