Like many a keen amateur runner, the prospect of shaving a second or two off my personal best is enticing. I'm not striving for anything extreme: running a 5K in under 30 minutes is the target. I last managed this in 2016, but the intervening years had not brought a repeat performance, no matter how often I tried. Sure, I have my excuses: I weigh more than 12 stone (76kg), have a love of red wine – and, oh yes, I'm 80 years old. (The weight and the wine count against me far more than the years do.)
I've been running since the 1950s, when I was a student at the University of St Andrews. I ran in the cross country club, usually towards the back of the field as I never really was any good. I ran all through my career as a journalist and writer in London and in Scotland, heading out at 6.30am in my trainers before starting work at 8am.
I ran the first ever London Marathon in 1981, when I was 42 years old, completing it in just over three hours. Even now that I'm in my ninth decade, there isn't a day I don't run. Some days, it's only a 3km jog; once a week it's a 16km run. Typically, it's 6 to 8km, off-road along the cycle ways of Edinburgh, with only my thoughts for company. (Music I find far too distracting.) For me, it's become a routine as intrinsic to my day and wellbeing as brushing my teeth in the morning.
Since moving to the Scottish capital from Fife three years ago, I've taken part in the city's Parkrun each week, joining the 80- to 85-year-old group, but generally finding myself on a par with new mothers who are in their early 30s. My best time so far this year had been 30 minutes and eight seconds to cross the finish line.
Not bad for an old duffer, you might think. But what if I could do better? The question had not overly troubled me until I happened across a recent newspaper article about a pair of £240 ($480) Nike trainers that were said to be dividing athletics.