I would have finished the Richmond Park Marathon by now. Instead, I am mooching around my flat, having not run a mile, my thoughts drifting forward to a fortnight’s time when I will be – all being well – embroiled in an attempt on the Bob Graham round. I had to pull out of today’s marathon, although I left it until 9pm last night before making the final, inevitable decision. It is always disappointing to drop out. Not least because it’s the third time I’ve had to pull out of a marathon, having bailed out of a London some years ago and Loch Ness more recently.

There was no sense in starting and seeing how it goes. Running when I shouldn’t have been running caused this problem, so it would be idiocy to aggravate an injury unnecessarily. Besides, not starting must be better than starting and dropping out mid-race, physically and psychologically.

I’ve got form when it comes to this. Most hopelessly optimistic of all, I ran the Moray half-marathon several years ago, despite carrying a calf strain going into the race. I lathered the limb with some Deep Heat-type substance in the vague hope that this would somehow rid me of pain. It didn’t. Within the first mile (after going off fast), I felt (and heard) my calf pop. I carried on, limping all the way to the finish. I constantly entertained the prospect of DNF from mile 2 to 13.1, but wouldn’t allow myself to act on such poisonous thoughts. Besides, I had to get back to Elgin somehow; I may as well run.

And that is exactly what I would have done today in Richmond Park. I may have got round uninjured, untroubled, of course, but had the niggles returned I would have run through them, wouldn’t have pulled out, no way. So, to answer my self-posed question: when there is no such thing as DNF, the best course of action – to save me from myself, to save my Bob Graham – is DNS.