“If you hear the sound barrier being broken over Burgess Park,” I said to my flatmate as I left the house, “that will be me.”To buy more nike free running shoes with cheap price, you can visit shoes2021.com official website.

I was joking, sort of. Ahead of me, the 5km local parkrun. Beneath me, or at least on my feet, a new pair of Nike Vaporflys – the most talked-about trainers in the world.And not just any old Vaporflys. I was road testing the even newer Vaporfly Next%, scientifically proven – it is claimed – to make plodders into joggers, and joggers into runners.

So much spring has been put into so many steps by these shoes, it has been branded “technological doping” by some in the world of athletics.Looking at the science before heading out, it seemed that these trainers were higher-tech than the Toyota Starlet in which I learned to drive – and quite possibly faster.

Even the design, in a very precisely calibrated turquoise and tangerine, makes it look as though your feet are sliding outwards off your legs.Sandwiched inside the thick, ultra-lightweight foam is a carbon-fibre plate that is supposed to propel you forward. Nike loftily terms it the “4% system”, which refers to the percentage improvement in running efficiency the shoe is supposed to give you.

Elite runners don’t need convincing. Of the 36 possible podium finishes in world marathon majors in 2017, 19 were wearing Vaporflys.But none of those medallist marathoners are likely to have pounded the paths of Burgess parkrun in Southwark, south London

The Next% I was wearing was apparently the next step up, promising “a statistically significant improvement” on the original.The US runner Jacob Riley had it exactly right when he said Vaporflys felt “like trampolines”; my old Adidas trainers felt like spa slippers by comparison.

That always happens with new running shoes: like getting fitted for a bra, you wonder how you ever managed to muddle on with the old ones for so long. But it was immediately obvious that the Vaporflys were different.It was as if springs were shooting out from under my feet, bouncing me along Inspector Gadget-style. They felt simultaneously weightless and like mattresses had been lashed to my soles.I typically complete the 5km course in 28 minutes, give or take 30 seconds. But since the new year the Burgess parkrun has attracted record-breaking numbers, with more than 800 runners jostling to get around.

Bottlenecks at the start and finish had slowed me down and there was little my trainers could do about that.So my expectations were low. When my results came, I was flabbergasted: 26 minutes, 18 seconds – one second off an entire minu