Two years on from the release of the Nike Ultrafly – the brand’s first The shoe has already featured on the podium of major trail races – we finally have a follow-up in the form of the ACG Ultrafly.
For those who aren’t familiar, ACG stands for All Conditions Gear; a branch of the Swoosh's outdoor wear that sits separate from Nike Trail and has previously been associated with rugged gear for hiking and lifestyle purposes. By the looks of things, though, the ACG Ultrafly marks a shift in how Nike is going to be approaching trail gear going forward.
In fact, the shoe’s grand unveiling coincides with Nike's newly formed All Conditions Racing Department, consisting of 22 global athletes from eight countries. Among them is Caleb Olson, who won this year’s Transgrancanaria Classic and Western States wearing the ACG Ultrafly and has played a role in their development.
What everyone's reading
‘It’s a great balance between all-day comfort and top-end performance that has helped put me on top of the podium at some of my biggest races,’ he said, speaking on the shoe.
So, what’s new? Well, unsurprisingly, Nike was keen to find ways to make the shoe lighter and more comfortable, while increasing responsiveness and stability. The shoe has undergone 13 rounds of testing encompassing more than 30,000 miles, and has even gotten Eliud Kipchoge's seal of approval, with the GOAT declaring, ‘I think this one is ready,’ upon testing the final prototype.
The midsole consists of full-length ZoomX foam, combining two different densities (one is slightly firmer to add stability) and a 7/8-length carbon-fibre plate. It’s less rigid than the one used in the original Ultrafly and is split down the middle for flexibility when running over roots, rocks and difficult terrain. A ZoomX sockliner adds comfort, while the shoe is built on a wider last than its predecessor with a redesigned upper, more accommodating toe box, internal fit band and gusseted tongue deliver an improved fit. Finally, a Vibram Lightbase outsole balances grip and weight savings.
Moab 240: All you need to know and everyday outdoor athletes across all trail disciplines, from one-kilometre vertical ascents to multi-day staged events. It will be available in women’s and men’s sizing.
‘From the beginning, the Nike ACG Ultrafly was developed in lockstep with our Nike athletes who desired a trail-tuned super shoe,’ says Brenden McAleese, Director of Nike ACG Footwear. ‘They pushed us to rethink what fit, form and feel could be for a trail shoe, and every design decision was informed by their feedback and validated in the wild. This shoe isn’t just inspired by the terrain. It’s engineered to redefine how fast you can move with it.’
The ACG Ultrafly will be available from spring 2026 at Nike.com and selected retailers. As always, we'll bring you our full review once we've had a chance to test it thoroughly.
