So I went to Paragon Sports in Manhattan, where they had the Nike Alphafly 3s on a special display, promising they were the company’s “pinnacle race day show,” which I figured was a typo. That said, they were a bit of a show: I would call the uppers diaphanous, but the material was so synthetic. They were more like cheap lingerie for my disgusting feet, which I could see through the proprietary Atomknit mesh; the sole was as tall as a stripper’s heel. They looked somehow boatlike, all forward tilt, bottom-heavy with foam and air bubbles. Picking them up, they seemed too big for how light they were, lending them the uncanny feeling of pumice, or that freeze-dried astronaut ice cream. Even the laces felt oddly weightless. I bought them: $332 after tax.
The magic of super shoes is in the carbon fiber plate running through the middle of the sole. The hard material spreads the energy your footfall generates around the piles of foam, springing you back up as you finish your stride. Maybe because this sounds like cheating, it is instead known as “energy return,” as if to suggest that your footwear or the ground or something owes it to you. According to testing on the website RunRepeat.com — a very thorough process that involves six-figure machinery and cutting all shoes in half with a saw — the Alphafly 3s return almost 75 percent of the energy you deliver into them. Jens Jakob Andersen, the founder of RunRepeat, told me pre-foamaissance running shoes return something like 35 or 40 percent.
Andersen seemed slightly disappointed to learn I’d bought the Alphafly 3s. Though they were once leaders in the super-shoe category, they’ve quickly been surpassed. Adidas’s super shoe, the absurdly named Adizero Adios Pro Evo 3, was worn by the two runners at the London marathon who completed it in under two hours. These shoes show energy return of around 80 percent. They also cost $500 and are meant to be worn only once. (In fact, none of these race-day shoes are meant for daily running; their harder soles and lack of stability mean they can lead to discomfort and injury from overuse.)
On my first test drive with the Alphaflys, I could feel the air bubbles pulsating under my forefoot, and wondered if I was supposed to be “aiming” for them — somehow. I thought I could sense the shoes spring more as I lengthened my stride and got my toes more involved, but I wasn’t totally sure. The Alphaflys reminded me of a Lamborghini; they seemed like something I should have taken a class to learn how to use. I also wondered if they made me look like an insecure schmuck with too much money.
To really put them to the test, I wore them to a 5K at Prospect Park. I’d run two of these earlier in the summer. My best time was a little under 21 minutes. I was pleased with this, until bumping into a friend about an hour later who was captain of his high school cross country team. He told me it was pretty good — for J.V. I wondered if the shoes could get me under 20 minutes. Maybe I could be the slowest guy on the varsity squad.