The loneliness of the short distance runner

There is always the physical limit of the end of the pier.
No matter how much this jogger wants to surpass himself, the end of the pier is there to keep him in check.

I used to hit a mental wall at around mile 20 when I used to run marathons (does 3 of them allow me to say "used to"?)

Nowadays my mental wall is at around 2 miles.

That's progress!