Marketing Assistant Sam was lucky enough to test the all-new Mammut Aenergy GTX Lows. But can these lightweight trail hiking shoes convince him to switch from heavier boots?
In recent years, we’ve seen a noticeable shift in outdoor culture: from heavy packs and full-grain leather boots to a new ethos of light and fast. This change hasn’t just influenced what we carry – it’s reshaped what we wear. More hikers are trading in stiff, heavyweight boots for agile, cushioned trail shoes, when appropriate.
This is where the Mammut Aenergy Hike Low GTX was created. Born from the intersection of trail-running agility and hiking durability, the Aenergy Low is Mammut’s answer to the modern fast hiker.
It’s built for those who move quickly and confidently on steady trails, offering exceptional grip, support, comfort and weather protection without the bulk.
Fit & First Impressions
Straight out of the box, the Aenergy Hike Low GTX looks and feels like a quality bit of kit. The first thing you notice is just how light they are, coming in at just 420g (UK 8.5). I have to admit that I was a sceptic and I’ve always leaned toward leather boots, my Altbergs have never let me down.
So naturally, I questioned whether a shoe like the Aenergy could genuinely provide me with a solid alternative for longer day hikes and multi-day treks.
But the moment I slipped them on for a short walk around the block, my mindset started to shift. The comfort was immediately noticeable with a more forgiving midsole than the hardened ones I’m used to. I could already see how much more pleasant these would be on warm days and rocky trails.
After a few more days of breaking them in, I decided to fully commit and take them as my only footwear option for a week in the Lake District- covering over 100 miles and then straight into another week walking the Cornish coastal path.
Favorite Features
One of the standout features is the stack height – 35mm at the heel and 27mm at the forefoot. That generous EVA midsole delivers an incredible level of cushioning, which, quite frankly, puts my traditional boots to shame. On long downhill stretches – where I’d usually feel every step through stiff soles – these felt responsive, smooth, and surprisingly forgiving. The impact absorption here made a noticeable difference in how fresh my legs felt by the end of each day as well as the soles of my feet.
Mammut have also built in a rocker-shaped sole, which encourages a smooth landing and effortless toe-off. It makes the shoes feel intuitive and fluid underfoot, perfect for covering ground efficiently. I was initially concerned that the higher stack height might make things feel unstable, but that wasn’t the case at all – if anything, the shoe felt more planted than expected, even on uneven trail sections.
The synthetic upper was another win for me. These were my first synthetic hiking shoes, and I was genuinely impressed by how breathable and comfortable they were during hotter days. My feet stayed cool, and the materials still felt robust enough for rugged use. Add in the Gore-Tex liner, and I had no worries crossing shallow streams or getting caught in a shower the waterproofing was solid throughout.
Lastly, I’ve got to mention the tongue and lacing system. The laces have just enough stretch to accommodate foot swelling over long hikes without creating pressure points, and the pre-shaped tongue sits flush with no rubbing or discomfort. It’s a subtle but meaningful touch that reinforces what this shoe is all about: delivering all-day comfort in a lightweight but capable package.
In the wild
As promised, the Aenergy Hike Low GTX was the only footwear I took with me to the Lake District – a bold decision given the region’s famously wet and unpredictable weather. Luckily, we were blessed with mostly dry conditions and clear trails. On average, we were covering 15–18 miles a day across a mix of terrain: damp woodland paths while chasing waterfalls, and steep, rocky trails winding toward the peaks of the Lakes. In both scenarios, the Aenergy held its own, providing consistent comfort and reliable stability throughout.
The 4mm lugs on the Vibram sole handled everything I threw at them, with only very wet, slick rock presenting the usual challenges. On more technical sections, I found the reinforced toe bumper especially useful – after several long days, I was definitely kicking the odd rock, and this protective element, combined with the durable EVA fabric wrapping the lower section of the upper, helped keep the shoe in great condition. I think if the more open, breathable synthetic fabric extended all the way down, it would wear out faster- so this layered construction is a smart move toward long-term durability, which is often a weak point in lighter synthetic shoes.
Overall, the Aenergy exceeded my expectations in the Lakes. It proved that a lightweight, cushioned shoe absolutely can cope with British landscapes and weather. Even while carrying a full pack with all the gear we needed—including kit for the dog—I remained stable, supported, and blister-free.
A few weeks later, we headed to the Cornish coast for a different kind of challenge. The South West Coast Path is a relentless mix of steep climbs, sharp descents, narrow cambered trails, and exposed cliff edges – all of which push footwear in ways that mountain trails often don’t. Although the daily mileage was lower, the physical toll was just as demanding. Loose gravel sections had me relying on grip and foot placement, while uneven steps and deep ruts required careful balance. Wet grass, hidden roots, and slick mud after rain meant I was constantly moving between traction types, and I never once felt unsure of my footing in the Aenergy.
There’s also a lot of hardpack underfoot on the Cornish path, especially near villages and harbours, and this can be punishing over time—but again, the generous cushioning came into its own here, soaking up the repetitive impact that normally makes your feet ache by mid-afternoon. The rocker sole really shone on this terrain too, helping me maintain pace on long stretches where the trail flattens out along headlands.
Perhaps the biggest test, though, was versatility. On the coast, you transition quickly – from muddy climbs to gravel switchbacks, from rocky outcrops to walking through town streets – and this is where I saw just how well-rounded the Aenergy really is. It handled every surface without hesitation, drying quickly when it got wet, keeping my feet cool on hotter days, and never feeling out of place whether I was on trail or tarmac.
Pros and Cons
Pros
- Very Comfortable for longer hikes
- Breathable but still capable
- Robust but very lightweight
Cons
- Makes me not want to go back to my harder Altbergs
- Lower ankle profile takes some getting used to after wearing boots
So, has the Aenergy changed my mind? Has it earned a place in my kit?
Simply – yes.
I’ve been genuinely impressed with them, and I’m glad I gave in to the growing shift toward ‘light and fast’ footwear. The Aenergy offers a noticeably more cushioned, more comfortable alternative for those times when you’re moving quickly and packing light. No, they won’t replace my trusty old leather boots; they still have their place in tougher, more punishing conditions, but the Aenergy will now be my go-to whenever the terrain and weather allow. They give my feet a welcome break from the rigidity and weight of traditional boots.
It’s rare that a piece of footwear changes your mindset on what you reach for before a day on the trail, but the Aenergy has done exactly that, offering a new perspective, and most importantly, a new level of comfort, without sacrificing capability.
