success of serena, Federer, djokovic, and now andy murray should provide plenty of motivation.
serena and Federer are older than dirt and they are doing it. one is ranked #1 and the other one is #2.
djokovic is outworking them all. he works out 3 times a day and never misses a day. he also practices year around on clay as much as possible. that keeps his knees and joints healthy and also keeps his ground game tuned up and sharp.
and now andy murray is working very hard also.
unless rafa starts training 7-8 hours a day on clay it is going to be extremely hard for him to win even a 250 level tournament going forward.
that is how much his game and his fitness has dropped.
it is really that simple. he has to work if he wants it bad enough.
and the in the off season--which is a lot longer now than it used to be--he has to put in very long and hard yards on the fitness front.
there is no other way out.