I rediscovered trail running after interviewing the 2019 Marathon De Sables champion Ragna Debats (she’s also a Merrell ambassador). I wasn’t expecting much in the way of practical take-home from such a hardcore long-distance runner. But she talked about how to prevent injury, and said her worst marathon had been in Hong Kong: a lot of stairs, but mainly a lot of concrete.

That’s what’s been going wrong, I thought: whenever I’ve given up running, it has been because some part of my body has given me a funny twang, as if the next time I tried that caper, it would snap. I’ve tried resting, physio and resistance-band work to build up the muscles around the joints. Maybe I should just stop running on concrete.

If you’re running on grass, the most important thing is to give up the relentless measuring, tracking and Fitbitting. You don’t go as fast. There are always inclines you’re not expecting. Sometimes it’s muddy, which means you have to slow right down or fall over, which slows you down more. You have to give up the whole fandango of setting specific goals – 90 more seconds, one more circuit, whatever you normally use to keep going. And this can be a big deal, since improving is probably the fundamental motivation that gets you out of the house.

I had to get past all that counting, and I succeeded (to some extent) by concentrating on the outrageous beauty of even the mankiest park. If you have to look where you’re going anyway, you may as well look around at the trees, at the crocuses poking early through the knolls, at other people’s dogs and their woolly jumpers. I never did the same route, or even the same park two days in a row. I replaced target-setting with goals that would infuriate a statistician; if you can run for four songs today, run for five tomorrow. Nope, it doesn’t matter how long the songs are. How far through the American war of independence could I get if I ran to the musical Hamilton? Not that far, it turns out. (I couldn’t even tell you who won. Well, if I didn’t already know.)

Elite athletes are much more likely to talk about weather than terrain; rocks, camber, potholes, none of that seems to bother Debats in the slightest. She’ll just about admit that sand is harder to run on than almost anything else, but otherwise her enemies are wind and heat.

By contrast, I have been slogging through the same indifferent British half-winter since November, and it’s been perfect for trail running: cold enough to speed me up but never icy.

I got some better trainers, with deeper lugs, further apart, which seemed to make me a little more pacey. I’ll tell you what, though: sometimes, things still hurt. Knees, mainly; occasionally ankles. Grass may not cost as much to your joints as concrete, but nothing comes for free.

Try to take at least one run with hills in a week; it counts as interval training, sort of, and good for morale when you get back to the flat.