When do we get old

I feel fortunate as I will turn 60 this month. I have aches and pain in my back but I work thru it daily with aleeve and back medication when its really bad. Doc says I have arthritis in my back and in my hands. Good thing is i dont have it in my knees (yet). I play and walk at least 54 holes of golf weekly and I use a teeter to hang from trying to stay loose.
I tell my wife and kids that life is broken down into 3 stages, 1st stage (birth to mid 20's) is growing up and having your parents and teachers tell you what to do and when to do it. 2nd stage (mid 20's to mid fifties) is raising your kids and that takes all of your time and money as well as sets up your social functions in life, and finally the 3rd stage is for you to do as you damn well please because its your time and you have earned it!!
Im in that 3rd stage and I do pretty much as I want and when I want it. I try not to take to much away from the others in my family but I want them to understand at this age we only have so many good years left I want to make the most of them as I have given everything I could during that 2nd stage.
I look in the mirror and I dont see an old man yet. Hoping that never happens!
Rod