I'm 69, and in the fifth week of an adapted 8-week 5k-10k bridge course, which involves a short (3k-4k) run, a 5k run and a gradually-increasing- to-10k run.
I've been doing the short run on Tuesdays, the long run on Thursdays and Parkrun on Saturdays.
I do stretch and strength exercises on the other days, and walk 10 miles on Sundays.
This week, I should have done 8k for the second time, but I decided to test my progress by running 5k along the local former railway line, leaving me with no option other than to turn round and run 5k back.
No problem...back to base pretty well spent, and in a smidgeon under 60 minutes, with 10k under my belt three weeks early.
At Parkrun today, I paid the price. Since Laura banned walking in Week 5(?) of the Couch to 5k, I have never walked a single step during a run, on the grounds that if I gave way once, I would find it more difficult to resist in future.
But how I kept going, I do not know. For once, I did not enjoy a run.
Lesson learned. Back to the programme next week!