When I was 45 and did not get under 17 in a 5K friends asked why?
Now I am 10 minutes slower and people pat me on the back and are amazed at my old fat ass.
I know the truth as do geezers reading here like Marty and Ralph. I am lazy and not motivated to train. I have the physical and mental ability to run 21. Not many my age do. I know what 21 requires, and I am not yet willing.
I have my yard, my birds, my critters my fishing, my TV. I'm not just too fat, I am too happy.
I don't see peers every day (or any day) to push me like before I moved back in the woods to paradise.
I like what Jessie wrote over on RoadKill.run as to "fear of loosing". 25 years back I ran not so much to win, but not to loose. Like RobertM posted, I thought about racing all day, everyday.
If word arrived my Bride had been kidnapped or Martians had landed downtown, the first thoughts to my brain would be as to how it would effect my training. I just don't have that motivation now.
I still expect to win more than I loose this year. In 2016 I raced 10 times and won 7. One time my hamstring tore the first 100 yards, and the other two a guy 75 beat me by a lot! I am not going to beat that guy this year, but I do still hold win totals from history over him. If I can close the gap on him by a minute, I am calling it a win. I don't deserve to race like that guy as he is doing the work in training.
Here I am at 55 for a race where all the police rookies were required to run. The Cop Department had told me I was too old to be a cop any more. Of course I won the race -- just to prove them wrong!