I'm 51, been playing since I was 19. Although I haven't played in a gigging band since 2011 (dad duties) I'm definitely the best I've ever been right now. Sometimes I go weeks without playing, but I never stop thinking about it, listening and learning and my touch has lightened so I don't feel that rusty when I do get stuck in again.
I really should start doing yoga again though to get the rust of the rest of me π