A year after taking the running scene by storm with the Vaporfly 4%, Nike has released an update to the exceptionally fast racing shoe and greatly improved its fit while reducing weight. The Nike Vaporfly 4% Flyknit, as the name suggests, incorporates a new one-piece knit upper that seamlessly hugs the foot. The change from a lightweight mesh used on the previous version reduces irritation and improves breathabilty, too.
An all-new upper
While everything under your foot remains the same, everything that wraps over the top has changed. The new Flyknit model uses a one-piece bootie-like construction that fits exceptionally snug around your foot. It’s definitely a racing fit, with a tapered design to contour to your midfoot and opening just enough in the front to accommodate your forefoot.
The design is a lot like what we’ve seen on the Epic React Flyknit, but the knit used here is even less stretchy, which runners will appreciate as it bolsters support. The upper lacks any other typical reinforcements like overlays and a heel counter, but does have thinly padded patches and sueded materials inside to secure the foot to the soft platform.
The springy midsole remains unchanged
As noted, everything that you stand upon remains the same as Nike’s original version of this shoe. That means you’ll still get the thick slab of bouncy ZoomX foam, which in our lab tests on the original we saw delivered 80 percent energy return in the heel—the highest values we’ve ever measured in the lab.
That foam is paired with an extremely stiff carbon-fiber plate, which runs from heel to toe. The purpose of the plate is to extend push-off through the tips of the runner’s toes, essentially making it so the toes don’t bend—reducing the amount of energy the runner uses while increasing propulsive forces.
Women: size up
The Vaporfly 4% is available in unisex sizing. Our recommendation is to go up at least another half-size, or possibly even a full size.
Will the Vaporfly 4% make me run faster?
The Vaporfly has been controversial since its launch because it’s been shown to make runners faster—by making them, on average, 4 percent more economical. There’s not a direct 1:1 correlation between running economy and speed, but data in a recent report by the New York Times found the shoe increased marathoners’ chances of earning a PB.
What else is new?
Nike have also announced their new Nike Zoom Fly Flyknit, combining the responsiveness of the Nike React foam, with the breathable support and structure of the flynit and the full-length carbon-fiber plate found in the Nike Zoom Vaporfly 4%.
When can you get a pair?
The Nike Zoom Fly Flyknit will be available in neon-on-black colourways from 13 September on nike.com.
When it comes to the Nike Zoom Vaporfly 4% Flyknit, runners will have to wait until 1 October to buy them online and in stores. That said, you could be in with a chance of unlocking early access by participating in a Nike Running Club challenge, by running a marathon over a period of 10 days.
A version of this article appeared on Runnersworld.com