Nike’s Newest Super Shoe Is Lighter and More Energetic Thanks in Part to Radio Waves
Nike has unveiled the Alphafly 4, its highly anticipated super shoe coming nearly three years after its predecessor. The race model's lead designer spoke with Footwear News about how it's been improved.
Nike‘s newest super shoe has taken longer to arrive than consumers expected but released sooner than the company had originally intended.
The Nike Alphafly 4 gets its both its formal introduction to the world Thursday and a surprise, limited release nearly three years after the launch of its predecessor.
A typical script would have an unveiling with weeks or even months of build-up before the shoe becomes available, but Nike expedited the rollout in order for the race-day model to be eligible for use this weekend at the World Road Running Championships in Copenhagen.
Prototypes of the super shoe have been worn in other races over the past year — including for what was then a world record half marathon by Jacob Kiplimo in March and Conner Mantz’s American marathon record in October — but this competition requires footwear that’s already been made available to the public for purchase.
“It required us to act with a lot of urgency,” Bret Schoolmeester, Nike Running design lead, told Footwear News. “There were a lot of sleepless nights, but it was worth it to make sure our athletes had what they need.”
The tool Nike runners will go to work with this weekend is 5 percent lighter and boasts 10 percent greater energy return than the Alphafly 3. Foam and Air Zoom innovations deliver the most significant weight savings, as a new formula of ZoomX foam features alongside an Air unit produced with a new manufacturing process.
ZoomX LT, short for lightweight, comes in 17 percent lighter than the supercritical, Pebax-based foam that appeared on the Alphafly 3. The newer, softer material surrounds the carbon fiber plate while the previous ZoomX formula is used for the rest of the midsole to balance out the stability.
Instead of a process that essentially used heat to weld and shape the unit, the Zoom Air unit is now formed by using radio frequencies. Schoolmeester himself admits that he doesn’t fully understand vibrations can act as welders, but the change in methodology allows for a lighter plastic to be used for an Air bubble with tensile fibers that’s now 30 percent lighter.
Several other Nike shoes in recent years have been criticized for coming in heavy, such as the Pegasus Premium and Vomero Premium, with the blame largely being laid on Air Zoom. Schoolmeester insists the brand’s signature Air tech is still very much worth its weight and points out that, while weight is generally always an area of focus, it’s not the end goal but rather just one factor in the ultimate pursuit of running economy.
“Air still remains the most responsive cushioning technology we’ve tested,” Schoolmeester said. “We’re never going to be overly reliant on any one technology, but right now Air remains a very critical ingredient to help us make the best marathon shoes.”
Carbon fiber plates, one of the core elements of super shoes, are getting whittled down by many of Nike’s competitors. Across brands you’ll find shapes including forks, spoons and wings. Adidas is even reduced its use of carbon fiber to the rim of midsole on the Pro Evo 3, which was worn for the first (and second) sub-two-hour marathons in London this spring.
Nike is staying the course on a fuller plate because, in addition to offer propulsion, it acts as a crucial stabilizer in partnership with Zoom Air. Rather than getting smaller, in fact, the carbon fiber piece gets wider at the base.
As a complete package, the Alphafly 4 is intended to be just as useful for Nike’s elite racers as those finishing a marathon in four to five hours. Stability plays a large role in that versatility, a quality that can be lacking on some of the more aggressive super shoes on the market. The biomechanics team also paid major attention to smooth transitions through the ankles, joints of the foot and the shoe itself, as well maintaining an experience that feels the same at mile 1 as it does mile 26.
A smaller, faster audience could be in mind for another Nike super shoe prototype that’s been spotted a few times in the past year with a jarring cutout at the midfoot of its sole. Speculation has it pegged as the Vaporfly 5, but that franchise is typically a tier below Alphafly rather than above.
By all appearances, whatever it is would seem to be in line with Adidas’ Evo 3, which is priced at $500 and would be superfluous to the average runner. Schoolmeester couldn’t say much about the shoe but did promise it “push the edge of performance” and will be up for discussion “very soon.”
Following Thursday’s limited release, a wider launch is scheduled for Oct. 29 through Nike’s website and select third-party retailers.
Originally published by wwd.com. Syndicated material does not necessarily reflect the views of Glamour Canada.
