Putting the shoes on I was immediately struck by the softness of the cushioning
The most striking thing about Nike’s sub-two-hour marathon shoe when you lift it out of the box, apart from it’s slight resemblance to a 1980s tennis trainer, is the lightness – a men’s size 10 weighs around 195g.
To achieve this, everything about the upper has been stripped-down – it’s made of vented mesh, the tongue is thin rather than padded, and rather than overlays and a heel counter there are thin, padded patches of suede-like material to provide support with minimal weight. They feel almost delicate, and I suspect the name’s reference to the Nike Mayfly, a ultra-light racing shoe from 2003 that was designed to last for just 100km of running, is not accidental. This is a shoe you would keep for race day, rather giving it the full whack of a training schedule.
What’s also noticeable is how built up the midsole is – the stack heights are 35.7mm in the heel and 24.8mm in the forefoot, with a 11mm drop from heel to toe – quite a departure from the traditionally lower profile of the racing ‘flat’. The first evidence of the shoe’s ‘magic bullet’, the stiff carbon-fibre plate that’s sandwiched inside the midsole foam and runs from toes to heel comes when you try to twist the midsole in your hands – it feels stiff, even though the shoe is feather-light. The plate is designed to offer a spring-like effect and minimise energy loss during the toe-off without increasing demand on the calf.
Putting the shoes on I was immediately struck by the softness of the cushioning, and the strange feeling that the shoe is pushing you forward off your heels, presumably because of the curve of the carbon-fibre plate, which is marked on the side of the midsole in black. Once on the run, I did seem to be making a bit more sound with my steps than usual (I’m usually have a relatively quiet footstrike), but this proved that I was landing on the front of my feet. I tried heel striking for a bit and the sound dampened, presumably due to the very deep, soft cushioning in that area.
First impressions: the sole feels immediately bouncy, and I did feel as if there was energy return at work with each step. They don’t feel responsive in the way of a traditional or performance flat – the ride feels more tuned towards comfort and cushioning, and they might not appeal to runners who like to feel connected to the ground. The upper is comfortable enough, despite its stripped-down build, and the arch wrap and ankle patches do a good job of securing the foot in place.
Did they make me feel four per cent more efficient, as the name suggests? It’s hard to tell during a five-mile trot around Hyde Park, averaging eight-minute miles. But what was noticeable was that when I did a 50-metre acceleration near the end of the run and got properly onto my toes, the shoe seemed to come into it’s own, encouraging a quick, forward-leaning gait. They also seemed to propel me uphill better. They bring an almost effortless, floaty feeling on the run, and I suspect that over the course of a marathon this would make a difference. The shoe is designed to offer the sweet spot of deep cushioning combined with maximum energy return – generally shoes tend to offer one or the other, but on this evidence, Nike might have cracked it.