Given a choice of a risk on screwed up knees or screwed up heart / lungs I will take my chances on the knees.
All of the old people I have encountered who have had knee or hip surgery are generally unfit. Most of the old runners I know are generally fine and only complain about being as fast as they used to be. Granted its a small sample but I am yet to see one of these fabled aged runners in a wheelchair.
Join a local council gym for 3 months and save yourself a lot of cash. Chances are the equipment will be better and you will have more cross training options.
2 years ago I had pneumonia. I know it was probably unconnected but I could not help thinking it was 0 degree 6am runs that did it for me. This year I did most of my running in the gym through the worst of the weather but honestly I regret doing it.
Like others have said it sounds like balls-to-the-wall-max-effort post run pain to me.
I tend to follow the a routine and I find it helps. My long runs are on Sunday and I usually pace about 80% effort. On Monday I rest and then on Tuesday I will go for a very short and light jog and combine with some stretching, strength or yoga type exercise.
The rest of the week I will do a few more runs at higher intensity but shorter distance than my long runs.
When training I always have a nice dull ache in my legs but it always feels like a nice tiredness. I would never call this actual pain.
How do they calculate £1 per runner per run of damage? That would be over £10k per year of maintenance? Must be an amazing park......
It smells of a parish council trying to scam some extra funding with a grant out of the county council. I am not sure they would be allowed to enforce parking charges and keep the income themselves (parish councils do not normally do that).
If they were genuinely concerned about damage I am sure that if they asked to put some collection buckets at the start a couple of times a year and ask for contributions I am sure they would collect all they needed.