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REVIEW: Inov-8 Trailfly Ultra G 280

Inov-8’s nitrogen-infused foam offers springy responsiveness in their newest trail shoe, one of our favorites this year.

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Who says small shoe companies can’t compete with behemoth brands? Nestled on the edge of England’s Lake District trail running nirvana, Inov-8 has been producing intelligently-designed trail running shoes for almost 20 years by focusing on lightweight materials and terrain-specific features. 

Its latest model, the Trailfly Ultra G 280, features a nitrogen-infused, high-rebound foam midsole that serves up an energetic ride and Graphene-enhanced outsole rubber for exceptional traction. 

After wear-testing the shoes extensively on trails in Chamonix, France, Zermatt, Switzerland, and Boulder, Colorado, I give them high marks for one of my favorite trail running shoes of the year. It’s not a perfect shoe—let’s face it, there is no such thing when it comes to running trails—but it’s a very energetic, reliable, stable, and comfortable shoe with no glaring flaws.

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Weight: 8.3 oz. (women’s size 8), 9.9 oz. (men’s size 9)

Heel-Toe Offset: 8mm (33mm in the heel, 25mm in the forefoot)

Why It’s Great

After making a splash in performance-oriented road-running shoes, hyper-responsive foams have become all the rage in trail running shoes this year. Although the goal is to provide a springy spark in every stride, not all high-rebound midsole materials perform the same. Some are too soft; some are too unstable. 

But Inov-8 is one of the brands that got it right with the new light, soft and highly responsive Flyspeed foam that is making its debut in the Trailfly Ultra G 280. The midsole provides a springy sensation in every step—both as it dampens the impact with the ground and also as it returns energy at the toe-off phase of a new stride—but it has enough structure to avoid feeling sloppy. Inov-8 says wear-testing revealed that the foam returns 65 to 68 percent of energy of every stride—about 20 percent greater than standard EVA-based midsole compounds—which helps it provide long-haul comfort and consistency for multi-hour runs.

(Photo: Brian Metzler)

While the smooth, energetic return from the foam is appreciated, so too is the stability and structure it provides. Although the foam is soft and semi-bouncy, it also semi-firm, too, meaning it doesn’t mush out on steep or off-kilter foot placements. Combined with reliable traction from the segments of Graphene-enhanced outsole rubber and the sufficiently wide footprint, the midsole/outsole chassis provides a solid, reassuring foundation for running on all types of trails. 

I also applaud Inov-8 for not making the mistake of trying to incorporate a carbon-fiber propulsion plate into this shoe, mostly because this shoe shines without an interior shank. For the most part, these plates often add more instability on variable surfaces than they add to forward momentum.

Pros

  • Although not a featherweight shoe, the Trailfly Ultra G 280 is a light, agile, and surprisingly versatile shoe that can handle a wide range of terrain. It’s built for moderate to very technical trails and able to handle a mix of dirt, mud, gravel, roots, rocks, and wooden stair steps with aplomb, but it can also cover smooth dirt trails and gravel roads well without feeling overbuilt.
  • The Graphene-enhanced rubber outsole has an array of 4mm lugs that provide reliable grip on both wet and dry terrain. The rubber sections are interspersed with 8mm deep channels of exposed foam that create vertical flex grooves that help the outsole remain pliable for dynamic gripping on uneven surfaces. (Graphene is a nano material shown to greatly improve the strength, durability, and elasticity of rubber compounds.)
  • The one-piece upper and sturdy interior heel counter help provide reliable foot hold that contributes to the shoe’s stable ride. The upper is made from a stretchy knit material that is both very breathable, but also durable and protective against sidewall abrasions. 

Cons

  • The Trailfly Ultra G 280 generally fits true to size, but it has a medium- to large-volume interior with a spacious, reinforced toe box that some runners might find difficult to cinch down, to eliminate slippage. (On a positive note, the toe box provides enough room for foot swelling on hot runs, and it helps minimize the inevitable toe-banging and  toe-stubbing that occurs out on the trails.) 
  • The geometry of the shoe makes this shoe feel maximally cushioned in the heel but fairly low-to-the-ground in the forefoot. That’s not an inherent problem, but occasionally pointy rocks can be felt under the forefoot.

Bottom Line

The Trailfly Ultra G 280 has a nice blend of cushioning, comfort, traction, and liveliness to make it strikingly effective on a wide range of trails. It’s not as protective as some of the mountain running shoes built for gnarly terrain, but it has enough protection without getting in the way. 

I found the connection with the ground to be soft, stable, and consistent, with virtually no slipping or ankle-turning throughout the 20 runs I logged in them. Inov-8 is marketing it for running on hard–packed mountain terrain, and I generally agree, although I found it to be adept at running through sections of mud, wet grass and snow, too. I’ll continue to run in this shoe, especially for long runs on moderately technical terrain and would consider lacing them up for a long-distance race.

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