Nike has introduced numerous trail running shoes, but the brand hasn’t come up with a style that’s gotten trail runners excited in the same way road runners lose it over the brand’s Vaporfly and Alphafly models — until now. Meet the Ultrafly. The Ultrafly is designed to help you move fast, no matter the terrain under your feet. And it’s a totally new design for the Swoosh: It’s the first Nike trail shoe to use a carbon plate, as well as the first to feature a Vibram outsole.
Elite athletes have been testing the shoe for two years, and buzz has been building over the last year, culminating in three top-five finishes at the 100-mile Western States Endurance Run in July. It’s finally available to consumers this month.
But does it live up to the hype? To find out, we put it to the test over two weeks, running multiple trails near Denver, Colorado, ranging from smooth singletrack to rocky climbs.
Nike’s newly introduced, much buzzed-about Ultrafly trail running shoe is lightweight and offers a super-speedy, super-responsive midsole. Its Vibram outsole adds some serious stability. The Ultrafly feels as good and secure running through gravel and rocks as it does through dirt, though the white color got dirty fast.
What we liked about it
The carbon and foam midsole
Nike’s Vaporfly and Alphafly shoes are two of the most popular styles in road racing. This is mostly due to the combo of a full ZoomX midsole, made of a lightweight and responsive foam, and a carbon fiber plate — which work together to propel you forward faster. In the Ultrafly, Nike brings that duo to the trails. (The ZoomX is the same, but the carbon plate is a little more flexible so it can better handle uneven terrain.)
Unlike the brand’s road shoes, the entire ZoomX midsole is wrapped in fabric to protect the foam, and after 20 rough miles in them, we didn’t see any scratches or gouges. That same fabric also acts as a kind of cage for the foam, providing more stability underfoot than you’d get in Nike’s road-racing shoes.
The Vibram outsole
Speaking of stability: One of the major complaints about Nike’s trail shoes has always been the grip underfoot. When you’re moving fast over a varied surface, you need a shoe that’s going to maximize traction so you have more control over your footing. Nike has always used their own rubber, and although they improved it in the Pegasus Trail 4 GORE-TEX (which we ranked as one of the best trail running shoes), it’s still not great.
The Ultrafly, however, is the first Nike product to (finally!) incorporate a Vibram outsole. This blend of foam and rubber is lightweight and springy but durable and sticky. On one rocky descent, where loose gravel covered larger boulders, we didn’t have any issues with slipping or sliding (despite our fears going into it).
What we didn’t like about it
The insecure fit of the upper
The one issue we did have was ankle instability. While the grip underfoot was rock-solid (even with relatively shallow 3.5-millimeter lugs), there were a few factors that contributed to us rolling our ankles several times. While Nikes typically run narrow, the Ultrafly has a slightly roomier fit, especially in the toebox. That led to some slippage inside the shoe, especially when worn with thinner socks. Running down hills and parts of the trail littered with rocks or roots felt particularly precarious. Plus, the Vaporweave upper is lightweight and breathable, but we would have preferred a slightly more secure, structured fit. Instead, we compensated by overtightening the laces, which dug into the top of our foot and caused hot spots under the ball of our foot.
It gets dirty AF
White seems like a risky decision for any trail running shoe. The Ultrafly looked gorgeous out of the box — as it should for $260 — but it was already looking dingy at the end of our first run. This shoe will essentially be brown by the time we put 50 miles on it, and that’s kind of a bummer.
How it compares
Carbon-plated shoes are still relatively new in the trail running world, and brands are still trying to dial in the right mix of softness and stability. We really like the Hoka Tecton X 2 ($225) and the Brooks Catamount 2 ($170), but the former doesn’t have the same propulsiveness while the latter lacks the softness of Nike’s foam-and-plate combo, and The North Face Summit Series VECTIV Pro Shoes ($250) feels similar but stiffer underfoot. The Saucony Endorphin Edge ($200) feels incredibly fast but very unstable, while the Merrell MTL Skyfire 2 ($200) is a barely-there shoe best for short, steep terrain or those who prefer a more minimalist feel on longer runs. The Ultrafly is one of the more comfortable shoes in the mix, but if it’s right for you will depend on the type of trail running you do.
Bottom line
While the Ultrafly is billed as a racing shoe — and it may work well for the pros — we think it serves regular runners better as a long-run option. It’s soft without sacrificing ground feel, the plate puts a little pep in your step and the grip underfoot will keep you from losing your footing on most terrain. But there’s a lot of room for improvement in the upper, and we’d recommend sticking to smoother singletrack rather than more technical trails in these.