Here is the worst kept secret in all of professional running: many of Nike’s top athletes have been wearing a prototype super shoe since (at least) last fall. And here is a not-so-hot take: Nike should finally reveal it to be the Alphafly 4 this Boston Marathon weekend. But will it?
Such an announcement would feel long overdue. Nike released its current Apex predator, the AlphaFly 3, into the wild back in 2023. In super shoe years that’s beyond a lifetime.
And, if the countless photos of professional runners wearing what looks like a slightly bigger mutant of the Alphafly 3 are any indication, it appears that the perennial trailblazers of the super shoe world are nearly ready to grace the rest of us with their new creation.
What We Know
We started to notice a new Nike prototype creeping into race photos last fall. It seems to have a slightly wider base than the AF3, but otherwise assumes a similar, chunky rocket ship silhouette.
World Athletics, the global governing body of the sport, requires that brands declare and submit for approval any super shoe that will be used in an upcoming sanctioned race. The list of legal shoe prototypes and sanctioned shoes is made public in the form of a spreadsheet on World Athletics’ site, so we can track when a new model pops up just before a World Marathon Major.
The Alphafly 4 has been on this spreadsheet for months under the name “Development Shoe 164.” Early photos and reports suggest that it carries more of Nike’s proprietary Zoom X foam in the forefoot to maximize energy return, an updated upper, a reconfigured carbon plate, and energy units or “Air Pods” (not to be confused with AirPods) integrated more deeply into the midsole. And, to appeal to a broader audience, the midfoot is mercifully wider.
Conner Mantz, two days before setting a new American record in the “Development Shoe 164” at the Chicago Marathon, called the prototype similar, but lighter than the Alphafly 3. He also mused that it “wasn’t that different” from the previous model. Sifan Hassan echoed his statements before wearing them to race New York, and even after lots of prodding from me, refused to utter the words “Alphafly 4.” I gathered that both Mantz and Hassan were under some type of order to not formally reveal it to be the Alphafly 4 — at least not yet.
Why the Alphafly 4 Is a Big Deal for Nike
Nike has been known to shock the world with their super shoe releases. Their original Vaporfly 4% was the first ever carbon-plated racer, and it changed distance running forever. The Alphafly 3 was arguably the first truly durable super shoe. It’s also the sneaker that Kelvin Kiptum wore to set the men’s marathon world record.
But the brand’s super shoe aura has dimmed over the last year. Amid a prolific 12 months of worldwide shoe innovation characterized by a three-ounce sneaker, powerful ATPU foams, seven-layer carbon plates, and smaller brands producing surprisingly good product, Nike has been oddly quiet, seemingly riding the Alphafly 3 into super shoe mediocrity.
In 2025, Nike did release the Vaporfly 4, a safe racing shoe made more for comfort and durability than top-end speed which feels like a less powerful little sibling to the Alphafly series. The Swoosh seemed outwardly focused on other projects than bleeding edge marathon shoes last year: there was Breaking4, featuring Faith Kipyegon trying to become the first woman to run under four minutes for the mile. That campaign leveraged lots of tech innovation, including a a one-off super spike.
Nike also aggressively expanded its trail running portfolio by refitting its All Conditions Gear sub-label as a serious (yet still very hip) high performance ultra brand. That project also included a significant overhaul of its flagship trail super shoe, the Ultrafly (now known as the Ultrafly ACG, which was just released in April).
Meanwhile, on the roads Nike’s competitors pushed super shoe innovation several levels up. Adidas dominated the podiums of major marathons, and now have the Pro Evo 3, which weighs less than half as much as the Alphafly 3, and is arguably just as powerful. Asics dropped three top-level super shoes in mid-2025 and each is arguably faster than the Alphafly 3. And Puma’s Fast-R Nitro Elite 3, surprise released in Boston last year, pulls together genuinely new ways of leveraging carbon plate technology that makes Nike’s super shoes feel downright primitive.
The Alphafly 3 was good enough to float the company through 2025; but it has clearly fallen behind, and it’s unclear if Nike has an immediate design innovations in the hopper to quickly catching up.
It’s been a tough time for the Swoosh: tariff troubles, supply chain issues, and a game of boardroom musical chairs that led to two CEO swaps since 2020 have chopped Nike’s stock price nearly in half. Breaking4, which must have cost tens of millions of dollars, and was an exciting spectacle for running nerds (and a keystone moment in promoting women’s track on a big stage) nevertheless felt underwhelming from a technology standpoint. There is a sense that Nike’s trying to find itself again. And so, in 2026 Nike very much has something to prove when it comes to bleeding edge running tech. After all, the company both invented and dominated the super shoe game such a long time. But now its fallen well behind.
What the Alphafly 4 Has to Be
Nike needs this thing to be more than just be a slight update to the Alphafly 3 (although, Mantz’s comments from Chicago echo loudly here: is it that big an update from the previous shoe?). It has be a hypershoe: a super shoe that goes beyond convention. These days, it’s customary for brands to have three tiers of racers. There is your classic super shoe: carbon plate, supercritical foam, widely available. That’s the Alphafly. Then, there is the safe super shoe, made for those who care more for durability and comfort than unfettered performance. That’s your Vaporfly 4. But on the other side of the equation is the hypershoe: an ultralight speed machine conceived for world-beating efforts. It’s ironically the origin story of the first Alphafly, which was conceived of as a part of Eliud Kipchoge’s quest to break the two-hour barrier. But now Nike is at least one echelon behind. Asics has the Metaspeed Ray, designed specifically for elite runners (the brand has said that if you can’t run at least a 2:15 marathon (!) this shoe probably won’t work for you); Adidas has the Pro Evo lineup, which for intents and purposes is the closest thing to a running shoe equivalent of an F1 car: no expenses spared, no thoughts about durability; all that matters is maximum performance over 26.2 miles. Even the Swiss brand On has a version of its super shoe that is spun by spider-like robots. Nike has no equivalent.
While it would be on-brand for Nike to release a super shoe that changes the game once again, I am not convinced the Alphafly 4 will be it. Conner Mantz running 2:04:43 in the new shoe is a good sign, of course. But then again, he ran virtually the same time earlier that year in Boston in the Alphafly 3. Maybe this time, Nike’s new tech won’t shift the paradigm.
If the Alphafly 4 is anything less than earth-shattering, Nike will fall farther behind Adidas, Asics, and Puma in short order. And if it does, it’s difficult to imagine Nike trailing those brands for too long. So, if the AF4 doesn’t innovate far beyond the Alphafly 3, and photos suggest that it doesn’t, it would be reasonably to expect Nike to release a bleeding edge tech hypershoe later this year that may look nothing like the Alphafly. Perhaps their own version of a Pro Evo. Or, in true Nike fashion, something that is totally other and new.
Will the Alphafly 4 launch in Boston?
Rumour sites and message boards point towards sometime in 2026 – with specific predictions ranging from January to October. Boston is an Adidas event, which could deter Nike from unveiling their latest masterpiece amid a sea of trifold emblems and three-striped jackets. But it’s also the unofficial world summit of running, and any marquee super shoe being released on Boston Marathon weekend is bound to reach virality even faster than usual.
So, if not by Boston, probably by London. If not by London, definitely by Chicago (which is a Nike sponsored World Marathon Major; there’s your hint on our prediction for when the Alphafly 4 is formally released).
