I have been experimenting with racquet weights and distributions and have settled on a polarized setup of about 345g. I really like the the heft of the racquet and the combination of stability and maneuverability. When I first went from a depolarized to polarized setup, I had a little trouble getting on top of my spin serves, but I soon worked that out. Yesterday, I played 6 sets of tennis (in two sessions)--mostly doubles but some singles too. I played pretty well all day, until the last set or two. I started missing shots I normally make, and the overall level of my game declined. I'm thinking that tennis is a lot like basketball, meaning that when your legs get tired your stroke declines. But part of me wonders if it is the heavier racquet, setup, which I've only been playing for two weeks or so. What do you think?