I'm not quite 60 but close, I think. A group of us are sectional hikers on the AT since 1998. We took a new guy this last trip who told me he was 60 and had to realize that he needed to slow down. I told him he was lucky I didn't have my hiking stick or he's we wearing it. He was in a lot of pain over this 32.5 mile leg.
One last note: I remember my birth month and day but forget (on purpose) the year. I want to be in my 80's and someone will ask "how old are you?" I want to answer, "I really don't know". My philosphy is that age is a state of mind!