The fact remains that the time spent hitting shots, never mind the actual time the ball spends on the strings is only a tiny fraction of the time spent moving to and away from your shots.
Best Park San Francisco 2011 - Crocker Amazon Park
The best dang dog park and playground in S.F. is at Crocker Amazon in the southeastern part of the city. Recent renovations have upgraded playground swings as well as the expansive green soccer fields, where neighborhood children gather and play every weekend. At Crocker you'll also find basketball courts, tennis courts, table tennis, a recreation center, and a dog-friendly walking trail. Take your pup out past the duck pond for a spectacular view of the city.