Adidas Terrex Free Hiker 2.0 Low GTX review

The Terrex Free Hiker 2.0 Low GTX must be on your radar if this is what you are after:

• a max-cushioned hiking shoe that keeps you isolated from obstacle-laden trails
• a highly stable and extra grippy shoe for technical terrain
• an outdoor shoe with an athletic sneaker style
• a preimium shoe that's built to last

If the hefty weight of this Adidas Terrex shoe is a dealbreaker for you, there are lighter options with similar intent and features that you could consider: the Salomon X Ultra 4 GTX (13.3 oz/378g) and the HOKA Anacapa 2 Low GTX (14.1 oz/400g).

Another reason to consider a different shoe is if you go on lighter and easier hikes. In that case, the Free Hiker 2.0 Low is definitely an overkill. Shoes like the Merrell Moab Speed 2 or the On Cloudhorizon are also well-cushioned but lighter and not so rigid.

Contrary to the brand's stated 30 mm of heel stack, our calliper showed a much higher reading of 37.2 mm! And frankly, the shoe's mighty platform does feel a lot like the latter. It is, in fact, a few solid milimeters thicker than the average hiking shoe!

For context, the Adidas Terrex AX4 has a heel stack of 30.6 mm and it feels significantly more grounded. The Terrex Free Hiker 2.0 Low GTX is more like a hiking boot in terms of impact protection.

The shoe provides a tonne of isolation from the rough ground which helped us worry less about sharp rocks and roots underfoot.

At 24.6 mm, the shoe's forefoot stack also proved to be higher than the promised 20 mm.

This generous cushioning kept the balls of our feet safeguarded from the elements and helped our feet feel less tired by the end of the hike.

Subtracting forefoot stack from the heel stack, we got a heel-to-toe drop of 12.6 mm in this Adidas Terrex shoe. It is slightly higher than the stated 10 mm but the difference is so subtle you can hardly feel it.

Especially since the shoe's drop is on par with the category average, you experience a very familiar heel elevation. It is an optimal offset for long hours of hiking with a backpack which takes the pressure off the foot and Achilles and shifts it up to the knees and hips.

Not only is it thick but the shoe's midsole is also quite cushy thanks to the prominent Boost foam in it. This soft blend showed a very low durometer reading of 14.0 HA which is a whopping 94% softer than average!

But even though this Adidas Terrex shoe feels soft directly underfoot, it is not as wobbly-plush as one might think. The Boost is complemented by a firm foam and a hard rubber outsole which make the ride feel balanced overall. What's more, the responsive nature of Boost makes the shoe feel quite sprightly.

Speaking of that firmer foam, we found that a pretty large chunk of it is concentrated in the shoe's toe area to soften the blow of hard rocks and sharp debris. It showed a very high durometer reading of 38.5 HA confirming its above-average density.

This firm foam also stretches all the way back to the heel on both sides of the shoe, forming a supportive carrier (aka EVA stabilisation frame) that adds structure and stability to the ride.

What's even more amazing about the Boost foam used in the Free Hiker 2.0 Low GTX is that it doesn't seem to be bothered by low temparetures at all!

Stunningly, after 20 minutes of sitting in the freezer, the compound only firmed up by 11%! The durometer reading still remained in the plush range showing 15.5 HA. And that is softer than most other hiking shoe foams at room temperature.

On top of its primary cushioning, the Terrex Free Hiker 2.0 also packs a sufficiently padded insole. Our calliper recorded 4.9 mm of thickness in its heel area.

It is equally important to mention the shoe's pronounced toe rocker which is more common for trail running shoes than it is for hiking footwear.

We couldn't help but notice how smooth and agile our transitions felt thanks to this curved geometry.

According to Adidas, the Terrex Free Hiker 2.0 Low GTX offers a regular fit and we can subscribe to that statement.

Measuring the cooled-off gel mould of the shoe's interiors, our calliper returned a solid reading of 95.4 mm in its widest part. This is an expected (regular) width for a D-medium shoe in a men's US size 9.

But please note that it's the only available width option for this Adidas hiking shoe.

On the flip side, the shoe's toebox shape is not as roomy as some people might hope.

While it still falls into the medium-width range at 68.8 mm in the big toe area, it is also a few milimeters narrower than average.

If you think you could use some breathing room for the toes, see our selection of hiking shoes with a wide toebox.

Gladly, there is no lack of vertical space in this Adidas Terrex shoe.

With a calliper measurement of 28.6 mm, its toebox height proved to be on par with the average.

It may look like a sporty sneaker on the outside, but we discovered a highly rigid personality inside the Adidas Terrex Free Hiker 2.0 Low GTX.

The shoe's main stabilising componets are, of course, the external TPU heel clip and the firm EVA stabilisation frame (or sidewalls). Both generate a lot of side-to-side support and contrainment for the foot which were revealed in our manual tests below.

The Free Hiker 2.0 Low proved to be highly resistant to twisting which earned it a high stiffness score of 4/5.

This amount of torsional rigidity helped us feel pretty surefooted on rocky and hilly terrain despite the shoe's very high stack.

The TPU heel clip also added a lot of stiffness to the shoe's heel counter. As you can see from our push-and-squeze test, the give is barely existent here. Thus, another high stiffness score of 4/5 went to the shoe's heel counter.

Adidas also made sure to provide extended contact points in the midsole to keep the foot more steady in the Terrex Free Hiker 2.0 Low GTX.

Our calliper measured an above-average width of 113.9 mm in the widest part of the forefoot. While it's not HOKA-wide, it feels substantial underfoot.

The shoe's heel also proved to be notably wider than average at 93.1 mm adding a lot of rearfoot stability (particularly on the descents).

This platform width, paired with the shoe's overall stable construction, made it more capable of shuttling heavy loads on multi-day trips.

Against all odds, this Adidas shoe proved to be sufficiently flexible in the forefoot. Neither its high stack, nor firm EVA, nor stiff upper material prevented the Free Hiker from bending freely under our toe joints.

As our flexibility tester showed, it takes 17.8N to bend the shoe by 30 degrees which is just as much as it takes an average hiking shoe.

This means that you can still get some natural foot flexion when going uphill or securing grip on technical terrain. It also makes the shoe feel agreeable on the more leisurely hikes.

Unfortunately, its above-average weight makes the Free Hiker 2.0 Low GTX not as fun and agile as it could have been. And we could feel it on the trail too.

The heft of this shoe reflected in a high scale reading of 15.7 oz (445g) which makes it one of the heaviest hiking shoes we've tested in the lab.

This is not a great option for speed hikers or light packers, for sure.

In this review, we are testing the shoe's waterproof Gore-Tex (GTX) version which obviously falls short of breathability. But you can get a more summer-ready non-GTX version which is also £20 cheaper.

As you can see from our smoke-pumping test above, not a tiny little billow of smoke is passing through the shoe's toebox. It's a 100% sealed and airtight area.

But on a positive note, you benefit from the shoe's top-notch waterproofing capacities. Just keep in mind that it only keeps you dry below the ankle so if you need more coverage, go for the high-top Free Hiker 2.0.

Adidas gets a standing ovation from us for incorporating a highly abrasion-resistant mesh in the Terrex Free Hiker 2 Low GTX.

We discovered that even in the areas where it's not reinforced with synthetic overlays, the mesh is capable of fending off scratches and slashes.

After a 12-second exposure to sandpaper in our Dremel test, the fabric showed only minor scuffing. This earned the shoe a high toebox durability score of 4/5. 

We aren't sure why the shoe's interior fabric wasn't as wear-resistant as the exterior one.

It only took a few seconds of drilling to leave a visible tear on the collar lining. Thus, we lowered the heel padding durability score to 3/5.

While this kind of wear doesn't affect the shoe's intergrity, it can result in some unpleasant chafing.

We can always tell a lasting Adidas shoe by a good old Continental Rubber. This tough and sturdy compound never disappoints and it proved to be hard in the Free Hiker 2.0 Low as well.

Our Shore C durometer showed a solid reading of 84.5 HC which is a standard for the hiking shoe category.

To test the rubber with brute force, we ramped up the Dremel speed to 10K RPM and drilled it for 18 seconds. And the Continental blend fought back so hard, it even made the tool tremble!

With a laughable dent of 0.4 mm, we can confirm that this shoe's outsole is built to endure.

We also found the shoe's outsole thickness to be adequate and on par with the average. With a calliper reading of 2.6 mm, we think that's a fair amount of rubber given its sturdiness and the shoe's already heavy build.

The Adidas Terrex Free Hiker 2.0 Low GTX uses two types of lugs as well as varied lug depth to provide an all-encompassing grip on varied terrain.

Measuring lugs in the shoe's heel area, our calliper showed an exceptional depth of 6.7 mm! This is some of the most aggressive treadings we've seen on hiking shoes! The hard bite of these teeth became particularly apparent on steep descents where braking was needed the most.

The midfoot and forefoot lugs, on the other hand, proved to be more moderate but still quite toothy at 3.6 mm. They made the Free Hiker a bit more versatile to cover less technical terrain as well.

We found the lug depth and spacing to be sufficient for shaking off some occasional mud but this is definitely not our first choice for boggy conditions (especially given its weight!). This is more of a mountain goat that feels at home on steep scree slopes, rock-heavy trails, and wet rocky creek bottoms.

The asking price of the Adidas Terrex Free Hiker 2.0 Low GTX is equivalent to its close competition from HOKA and Salomon. And we think it's fair given the amount of tech and premium materials in this shoe.

It is a performance-oriented max-cushioned, Boost-powered, Gore-Tex lined shoe for long-mileage hikes.

We spotted no reflective components on the Free Hiker which makes it invisible at night.

While it's not the most generously padded hiking shoe, it packs more foams in the spots where it's most needed. The thickest parts of its tongue, for example, reach 12.1 mm which helps to buffer the lace pressure.

The shoe's tongue is fully-gusseted closing off the instep gaps and not letting water or debris seep inside.

Large finger loops on both the tongue and the heel of the Terrex Free Hiker 2.0 make on-and-off fast and breezy.

Also nice to see that both loops are large enough to fit a whole finger.

The shoe's insole is easily removable in case you want to level up the comfort with a custom orthotic.

At least 20% of the shoe's components are made of sustainable materials - recycled or renewable.