I'm also old and slow. This would be for personal motivation/goals. We want to avoid competing and comparing with the young uns.
If you walk the 5k in 45min thats a major accomplishment because you've walked 5km.
All true, however the mind is still 18, although the body carries quite a few additional decades.
Luckily I'm still far away from walking, but I do not have notion to compete with my younger / faster / fitter self.
So, my PBs are written in the past, and I am fine with that. What would a PB at 18 or 28 be worth if you can beat it ~30 years later on.
Do I want to compete (against my *current* self)? YES - hence the the reference to age categories. So, maybe make the PB over distance "brag" more a case of your bests time over a distance in the past few year (5?)
Because then my PBs for
1/2 marathon goes from sub 1:45 to not applicable, and my;
10km from 47ish to only just sub 60, and my;
5km from 22:34 to barely sub 25
No point in referring to 2.4km, 5km and 8km PBs attained in the army or at school, when those times will be hardly attainable 2 or 4 decades later
The older I get the faster I was