Merrell Fiery GTX review: a beefy but agile running shoe designed to tackle tough trails

The Merrell Fiery GTX is a tough, aggressive, vegan-friendly trail running shoe that comes into its own in rugged mountainous terrain

The Merrell Fiery GTX on a tree
(Image: © Kieran Cunningham)

Advnture Verdict

The Merrell Fiery GTX fail to deliver on the promise of robust waterproofing but otherwise tick all the boxes for mountain runners seeking a shoe that offers plenty of agility without compromising on cushioning and protective features.

Pros

  • +

    Surprisingly agile

  • +

    Nicely padded tongue and collar

  • +

    Highly breathable

  • +

    Outstanding grip

Cons

  • -

    Relatively heavy

  • -

    Not as waterproof as promised

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Merrell Fiery GTX: first impressions

The Merrell Fiery GTX looks like a shoe you wouldn’t like to meet down a dark alleyway. The design is aggressive, boasting 5mm lugs so sharp that they could poke your eye out without careful handling and a tread you could easily grate cheese or sand your walls with. The Merrell Fiery GTX is clearly designed to be taken up steep hills on far from manicured trails. In addition to grippy outsole, it pairs a removable EVA footbed with a beefy EVA midsole for added comfort, cushioning, and stability in rocky terrain. There’s also a Hyperlock heel counter to help provide stable landings, support, and grip on steep descents, and a thin but tough toe rand to block any blows from rocks, roots, and debris on the trail. 

The lace loops are stitched firmly to the chassis, and two eyelets at the top provide for a nice, tight, foot-hugging closure that makes you less likely to have a shoe sucked off your foot when squelching through deep mud. The upper’s also highly breathable and Gore-Tex lined, and there’s a bellows tongue to prevent grit sneaking in at your forefoot.

The 8mm stack height means these are a little too lofty and aren't the best trail running shoes for anyone keen to develop a more natural running style. On the flipside, it does mean they will be suitable for a wider range of users, no matter which part of the foot they’re apt to land with. Their 1300g/1140g (men's/women's) weight is also likely to prove a little too much heft for anyone used to ultralight running shoes but is none too shabby given the support and protection they offer in return. As an added bonus, the Merrell Fiery Gore-Tex’s extra beef, brawn, and grip makes them a shoo-in replacement for my best hiking shoes on days when temps are high and the trails are relatively dry. 

Specifications

RRP: £100 (UK)
Gender availability: Men’s/Women's
Weight (men's): 650g / 22.9oz 
Weight (women's): 570g / 20.1oz
Colours (men's): Black and white/Turbulence (grey)
Colours (women's): Navy/Monument (grey)
Drop: 8mm
Compatibility: Ideal for forays into rugged mountain terrain

Merrell Fiery GTX: on the trail

I’ve had my pair of Merrell Fiery GTX for nearly three months and in that time we’ve clocked up around 250 miles together. That figure would have been a lot more if they possessed a few attributes that I feel they’re lacking but, importantly, would have been a lot less if they didn’t have a lot to offer nonetheless.

Let’s start with the not-so-good aspects. I bought the Merrell Fiery GTX after being lured in by the lean price tag and promise of solid waterproofing at a relatively light weight. After a few trail runs in the rain and on soggy trails, however, it soon became clear that keeping out the wet stuff wasn’t going to be their forte. On at least half of these runs, my forefoot area was damp within half an hour of leaving the tarmac. On the few occasions when I was less careful with my footing when splashing through shallow groundwater, the rest of my feet ended up a long way from dry, too. 

The Merrell Fiery GTX in a stream

The Merrell Fiery GTX were a little leaky when exposed to the wet stuff (Image credit: Kieran Cunningham)

That said, the Fiery do have a lot of redeeming aspects. For starters, they are surprisingly agile for such a beefy and protective shoe – you can take them on any mountain trail safe in the knowledge that your feet will be well looked after without having to compromise on your ability to negotiate testy terrain when moving at a fast clip. Secondly, they grip not much worse than your average pair of crampons, providing outstanding braking power on steep descents and plenty of control in the turn. Finally, the chunky EVA footbed and midsole, roomy toe box, and nicely cushioned collar, heel cuff, and tongue all combine to make them just about the most comfortable running shoes I’ve ever had the pleasure of putting my feet in.

Bottom line? Well cushioned, as grippy as they get, and a slightly more affordable alternative to lighter, high-performance mountain running shoes like the La Sportiva Bushido II or the inov-8 Terraultra G-grip 270.

Kieran Cunningham

Former Advnture editor Kieran is a climber, mountaineer, and author who divides his time between the Italian Alps, the US, and his native Scotland.

He has climbed a handful of 6000ers in the Himalayas, 4000ers in the Alps, 14ers in the US, and loves nothing more than a good long-distance wander in the wilderness. He climbs when he should be writing, writes when he should be sleeping, has fun always.

Kieran is the author of 'Climbing the Walls', an exploration of the mental health benefits of climbing, mountaineering, and the great outdoors.