I've done it!!! I've (more or less) run 5K, at the Horsham Park Run.
Less than three months ago I started out on C25K. If you'd told me then that I'd even be *thinking* about running 5k I'd have told you you were out of your mind.
But today I did my first park run. I hope it won't be my last, but I can't tell you what an amazing achievement this is for me. I ran with my friend Caroline - who is a running coach and proper inspiration - and she jogged along patiently as everyone overtook us. We weren't last, but not by much, but it is irrelevant.
Looking at my Fitbit stats, I actually ran the whole thing considerably under my normal 30' time even with a bit of walking here and there.
So it is possible guys, even for those of advanced age and avoirdupois. Thank you to everyone here for the encouragement to do it at all.