I've just hit 40 (yes, I know, I'm a sprog!) My body's absolutely hammered after a lifetime in the forces, I have to sit down to put my shoes on, and can't get up if I lie on the floor. I still think I'm 22, and on the bike I behave like a right tw@! Next day I suffer though. :-D
Bottom line is, your as old as you want to be!
Stop polishing it and ride the bloody thing!