Born for the wild, built for speed: the Nike ACG Ultrafly

Trail run doesn't play nice. Elevation swings. Rocks want your ankles. Every step becomes a battle with Mother Nature.

Enter the Nike ACG Ultrafly, a trail super shoe made for athletes who don't flinch when thunder cracks.

Tested over more than 30,000 miles of punishment on the world's most twisted terrain, it's the result of mountains of insight from trail running fiends.

The Ultrafly fuses Nike's fastest road DNA with ACG's dirt-first durability. Traction. Support. Confidence when the trail tries to buck you.

Nike's obsession with serving runners? Deeper than most canyons. On the road, track or trail, in sunshine or sideways rain, Nike running shoes have half a century of finish line bona fides.

Then there's ACG. With fearless design built to endure nature's extremes, ACG flipped the script on what outdoor performance gear could be.

The Ultrafly carries this legacy forward, equipping runners for places where maps go blank. It moves quickly, breathes easily and holds steady when the trail bites back. One foot in tradition, one in the dirt.

Every off-road stride demands focus and adaptability. Gear that moves with you, not against you.

The Ultrafly stays true to its roots with a design ethos built around speed, agility and athlete-first performance.

With a ZoomX midsole and a split carbon Flyplate, the Ultrafly is Nike's most responsive trail runner to date.

"This shoe isn't just inspired by the terrain", says Brenden McAleese, Director of ACG Footwear. "It's engineered to redefine how fast you can move with it."

The Ultrafly wasn't built in a vacuum. It was shaped by runners—men and women, pros and everyday grinders—who know what it takes to move fast through technical terrain. After 13 rounds of testing across 25 states and seven countries, this is the most rigorously tested trail shoe in Nike history.

Runners describe it as "light, fast, but stable", and "one of the best overall shoes I've run in straight out of the box".

Nike Trail athlete Drew Holmen calls it "a more stable shoe. A more responsive shoe. A faster shoe. Just straight better".

From vertical European mountain ascents to the podium at Western States, the ACG Ultrafly already has receipts.

• ZoomX Foam Midsole: Next-level energy return. Protection when the ground hits back.
• 7/8 Split Carbon Flyplate: Torsional support. Smooth chaos management.
• Vibram® Lightbase Outsole: Gold-standard grip, minus the weight.
• Breathable VaporMesh Upper: Durable, drainable and built to weather the storm.
• Gusseted Tongue + Fit Band: Secure lockdown. Long-haul comfort.

Bold proportions. High silhouette. Safety Orange that screams against the grey. Every detail is earned, not there for show.

From the pressure-tested ZoomX foam midsole to the rugged outsole, the Ultrafly comes ready for the climb up and the sprint down. It's a race-day weapon. Built for logging miles, chasing FKTs or enduring the multi-day odyssey.

"It's been my go-to, do-it-all racing shoe", says Nike Athlete Caleb Olson, 2025 Transgrancanaria Classic and Western States Endurance Run winner. "It can handle some of the most rugged terrain I've raced on at Transgrancanaria, as well as the singletrack at Western States.

• Weight: 287g (Men's 10) / 225g (Women's 8)
• Stack Height: 28.5mm forefoot / 37mm heel
• Drop: 8.5mm
• Lug Height: 3mm
• Outsole: Vibram® Lightbase
• Midsole: Nike ZoomX Foam
• Plate: Split carbon Flyplate