I turned 60 this past spring...but I'm only 60 for the first hour of each day. After that I'm still 18, unless I get reminded by a demand for strength or a passing mirror!!
Other than the realities of the calendar, my age varies by activity:
In a canoe, I'm forever 25.
Under a canoe, I'm about 40.
On skis I'm 50 on the way up (AT with skins) but 30 on the way down through untracked woods.
On a bicycle, I'm 50 at the start of the season, 25 by season's end!
On a motorcycle, I'm still 20, but without the immortal misconceptions!
When building a boat...I'm ageless!
Seriously, I've always said most people spend the first half of their lives ignoring their health, and then spend the second half being reminded of it.
I've been active and fit all of my life, but not without consequence. The way I see it, if you're active, you're bound to be injured at some point. Only difference between the young me and the current me is the length of time to recover...oh, and my shrinking biceps!
I respect and admire those that are my elder, whether chronologically or biologically, and hope to remain active and involved for many more years.