It’s only this year that I learned “PB” stands for “personal best”, and that runners sometimes make progress by measuring their speed over a mile. And it was some time before I successfully managed to time my PB – reason being, I didn’t want to. I knew it would be quite slow, and it was.

The first mile I measured, I did in eight minutes and 40 seconds. I wasn’t about to break any records. But here’s the thing: the next day it was slower (nine minutes, 15 seconds). “Ah, you’re about to break that famous milestone, the 10-minute mile,” said my Mr, with the sensitivity for which he is famed. A rest day, then a third shot: nine minutes and 5 seconds. If anything, this was the most demoralising of all: getting slower every day? At least that’s comical. Getting slower, then fractionally faster, but still nowhere near as fast as you were at your not-terribly-fast beginning: it’s just tragic, frankly.

At any point on this journey through mediocrity, I could have consulted an expert, which didn’t occur to me, but once it had, I went to the best: James Thie, professional middle-distance runner, ambassador for Saucony, the fancy trainers. “The body loves a challenge; the body loves variety,” he says, but I filter that out, because it’s exactly the kind of thing winners do say.

Turns out there are practical things you can do to improve your pace, things so well-established they have a name: strides. Already, it sounds more manageable than a 100m sprint, partly because it’s shorter: you go flat out for 15 seconds, which might take you no further than 80m, then give yourself plenty of time to recover. Don’t skimp on this. “You have to allow yourself to recover if you want to repeat it,” Thie says. “If you give yourself a few seconds, you’re going to get slower.” Think more in the region of 45 seconds to a minute – or if you haven’t got a timer, run flat out and then walk back the distance you’ve covered. “The recovery time is pretty arbitrary to whoever it is.” It’s a bit easier in fine weather, because you can run on grass, which has less impact on your joints. And you can do this four to eight times, either tagging it on to the end of a regular run, or as a really short workout on its own.

The thinking behind this is pure genius: you’re not trying to notch up distance; but if you acclimatise your body to a really fast sprint, it makes your regular pace seem slower, not to your intellect, but to your heart (literally, the muscle: I’m not making an emotional point). And this works: my max was never that high, I didn’t plan my routes carefully enough, the parks were full, sometimes I found that I was trying to run flat out up a steep hill, and to the untrained observer, not going flat out at all. And yet my mile did creep down, and steadily, until I hit the eight minutes. Read it and weep, Zola Budd.

What I learned

Shoes matter. If you change to a lighter, racier trainer halfway through an eight-week strides programme, it will really give you a boost.