By Brian Metzler
For the past 20 years, Nike has been in and out of trail running, oscillating oddly between indifference and all-in exuberance. Actually, it’s an up-and-down cycle that goes back much longer than that, dating back to the original trail shoes Mark Parker designed in the early 1980s. Why such fluctuation? It’s probably because trail running hasn’t been viable enough as a footwear category to hold down its own balance sheet figure in the grand scheme of accounting at Nike’s headquarters in Beaverton, Oregon. But trail running has been on the upswing for years, especially since the Covid-19 pandemic, and Nike appears to be fully invested for good.
Nike has been back in the game since about 2015, when it formed the Nike Trail Team of elite runners under the guidance of Pat Werhane and began rolling out new trail running shoes. Nike’s updated Wildhorse and Kiger models have continued to improve since then and, although the updated Trail Pegasus continues to be too heavy and cumbersome, last year’s Nike Zoom X Zegama was a big success. Nothing comes close to the work of art and science, however, that is the forthcoming Nike Ultrafly. Due out in a few weeks, it has the potential to be one of the best performance training/racing shoes ever made for trail running.
Nike unveiled a prototype version of the shoe last summer for athletes, select retailers and media/influencers to test out and, honestly, I thought it was pretty good but far from perfect. It was lightweight and had a hyper-responsive foam midsole, but it lacked sufficient traction and stability. To its credit, Nike’s trail shoe crew took the constructive feedback and went back to make several key tweaks, and the final product is exceptional. No matter if you’re a frequent trail runner who likes to run races or just an occasional trail runner who likes to meander, this is definitely a shoe worth checking out when it hits stores in early August.
What’s New: The Ultrafly has the same full Zoom X midsole as its Vaporfly and Alphafly road racing models and a similar curvy carbon-fiber propulsion plate embedded in the middle. Although the foam is soft and responsive, it’s not marshmallowy mushy because it’s been tightly wrapped by a thin, durable fabric material that protects and stabilizes the foam upon impact with the ground. The other key element of the Ultrafly is the Vibram MegaGrip Lite Base outsole for lightweight traction. (It’s the first time Nike has ever partnered with Vibram, which is a good sign that Nike was all-in on designing a near-flawless shoe.)
Fit/Feel/Ride: The Ultrafly fits true to size with a low- to medium-volume interior. There’s a little wiggle room in the toe box – much more than a lot of Nike shoes – that provides protection and a good proprioceptive feel for the ground. Although the shoe is very well cushioned, it’s not too much where you lose a sense of connection to the varied natural surfaces under your feet. The step-in feel is soft and comfortable, but sparse. The lightly reinforced Vaporweave upper has a race-ready vibe that contributes to an inspiration to run faster than you would in most traditional trail running shoes. The ride feels smooth and agile like you’re wearing a pair of performance-oriented road running shoes, but it’s sufficiently stable and protective on technical terrain. I loved running on all types of surfaces in this shoe, mostly because of the reliable traction from the semi-sticky rubber outsole. It doesn’t have the bomb-proof protection like mountain shoes from La Sportiva, Scarpa or Salomon, so running on especially rugged terrain and rocky ridges will definitely leave your feet exposed. But the high-traction rubber does a good job of balancing out and moderating those moments on highly technical routes.
Why It’s Great: The reason I’ve loved the Ultrafly is that it’s everything I want for running fast on trails – lightweight, stable, agile, grippy – and nothing more. So many trail shoes miss one of those marks and it puts everything else out of whack when you’re running fast. Nike had most of the pieces in place last year when it unveiled the prototype, but ultimately that version was unstable with unreliable traction. The addition of the Vibram outsole and the fabric-wrapped midsole foam give it superior stability and grip, and those are the elements that provide the ability and confidence to run fast on uneven, always-changing technical terrain.
Weights: 8.7 ounces. (women’s size 8), 10.0 ounces (men’s size 9) Heel-Toe Offset: 8.5mm (38.5mm in the heel, 30mm in the forefoot)
Why You’ll Love It: You’ll love it because of the energetic vibe it serves up in every step. Several brands have tried to implement carbon-fiber plates into trail running shoes, but so far only a few have got it right. (Hoka’s Tecton X 2 and Summit Vectiv Pro are two of the best so far.) Nike hasn’t released details about the shape or configuration of the Flyplate inside the foam midsole, but, as always with trail running shoes, it’s less about the actual components and more about how the sum of the parts and how they all fit together when you’re running over dirt, mud, rocks, roots, gravel and other debris. Suffice to say that Nike has figured it out with the Ultrafly. (Tyler Green wore a pair of Nike Ultraflys on his way to finishing second at the Western States 100 in June, but he wore a custom version without the plate.)
Pro: Although the Ultrafly is made for racing long distances, it’s actually a very versatile shoe for all kinds of trail running. My favorite Nike trail shoe before the Ultrafly was the circa-2002 Nike Air Tupu, which was light and moderately cushioned with a good feel for the ground. I loved that shoe because it was agile and stable enough that I could run all-out on even the most precarious types of terrain, but it wasn’t great for running long because it lacked sufficient cushioning. The Ultrafly has all of that plus cushioning for days, which gives it the ability to both run short and fast and have enough comfort for multi-hour runs. (The longest I’ve run in Ultraflys so far is a 2.5-hour run, but honestly, there were no complaints at all.) I don’t often buy running shoes (because I am fortunate to get free wear-test models) but I will definitely buy more pairs of the Ultrafly as soon as they become available.
Con: The only downside to the Ultraflys after running 75 miles or so in them is that they might not be as durable as the other rugged trail running shoes in your quiver. That’s not to say my pair has worn down much at all. They’ve turned to a dirty gray, but they seem as new and lively as the day I put them on three weeks ago. It’s just that they’re like a very light and nimble sports car made for rambling over rugged terrain, so you get the idea of what they might look or feel like after 250 miles or so.