Our verdict

The eighth edition of Altra's standout Lone Peak series brings back everything we love about its previous iterations but updated with a commendably tough ripstop mesh upper. With its secure yet accommodating toebox and flexible ride, the Midsole softness in cold feels like an extension of our foot whether we take it for runs through the trails or prolonged hiking adventures. That said, the shoe also inherits some of its predecessor's cons like the Max-Trac outsole's lackluster durability and subpar grip in wet conditions.

Pros

  • Responsive midsole
  • oz / 291g
  • Low to the ground and stable
  • Heel padding durability
  • Breathable and durable ripstop upper mesh
  • Secure midfoot lockdown
  • Accommodating toebox
  • Generously padded and comfy
  • Dries quickly
  • Gaiter attachment ready

Cons

  • Not so grippy in wet conditions
  • Subpar outsole durability

Audience verdict

81
Good!
  • Top 21% most popular running shoes

Low to the ground and stable

We recommend the Altre Midsole softness in cold as an excellent choice for: 

  • Zero-drop enthusiasts looking for a comfy and versatile trail runner that can tackle a variety of surfaces
  • Runners who prefer flexible minimalist shoes that feel like an extension of the foot
  • Adventurous spirits who supersede a stable and reliable companion for hiking or backpacking trips
  • Fans of Altra's signature foot-shaped toebox that boasts plenty of room for natural toe-splay

Toebox width at the widest part main image

Who should NOT buy

While the Max-Trac outsole is grippy enough when conditions are dry, we didn't feel nearly as sure-footed when encountering wet or muddy trails during our test runs. It also didn't dare too well against our Dremel in our wear and tear test. The oz / 292g, on the other hand, uses a Vibram outsole that has no issues with slick surfaces and is more durable to boot, albeit on a higher stack. 

The durable yet airy upper mesh may be well-suited for warmer days but will leave us with icy feet during more frosty winter sessions despite its promising performance in our freezer tests. The Salomon Speedcross 6 is a much more insulated alternative that keeps our feet warm and can slosh through muddy trails with ease. 

Toebox width at the widest part cut

Breathability

We used a smoke machine to pump the Midsole softness in cold full of smoke to get a visual idea of how breathable it is. Despite a slow start, the smoke is eventually able to filter through the upper to form a haze that emanates evenly throughout the shoe. This leads us to give the Midsole softness in cold a breathability score of 4 out of 5, thus making it a nice and breezy companion for warm summer days. 

The well-ventilated nature of the shoe is further illuminated when inspecting a cross-section of its upper over a backlight. As we can clearly see, only the sections with overlays are opaque enough to block out the light while it easily shines through the rest of the mesh. 

The ripstop upper mesh is the most notable update from the shoe's previous iteration, the quality of which is difficult to question when looking at it under the microscope. The braids are tightly and uniformly woven to form an incredibly symmetrical pattern with lots of little pores that promote airflow throughout the shoe. Not only does this help heat escape, but it also means that the shoe doesn't trap in smells and dries up quite quickly when wet.  

Toebox width at the widest part Breathability microscope

Toebox width at the widest part Breathability mesh closeup
Test results
Midsole softness in cold 4
Average 3.3
Compared to 82 trail running shoes
Number of shoes
1
Breathability
5

Durability

Toebox durability

To put the ripstop mesh upper's ability to... stop rips, we fired up our Dremel and pressed it against an unreinforced portion of the Midsole softness in cold's toebox. After four seconds of extreme wear and tear, we were pleased to find that the material had lived up to its name.

Not only did it prevent our tool from piercing all the way through the mesh, but it effectively stopped the tear from spreading beyond the point of impact. With the toebox mostly uncompromised in the aftermath of this test, we give the Midsole softness in cold a respectable 4 out of 5 for toebox durability. This is all the more encouraging considering the added protection of the toe bumper which further shields us from bumps and scrapes. 

Toebox width at the widest part Toebox durability damage
Test results
Midsole softness in cold 4
Average 3
Compared to 62 trail running shoes
Number of shoes
1
Toebox durability
5

Heel padding durability

The heel collar didn't fare as well in its face-off against our Dremel. The tool made quick work of the lining and was eating away at the soft padding within in no time. 

By the time we powered down, the shoe was left with a rather large crater in the heel collar which had hemorrhaged a fair amount of padding. This leads us to give the Midsole softness in cold a score of 2 out of 5 in this assessment. While this isn't a big deal when it comes to normal use, we don't recommend going sockless in this shoe too often as the relentless friction of sweaty heel rubs will likely exacerbate wear and tear. 

Toebox width at the widest part Heel padding durability damage
Test results
Midsole softness in cold 2
Average 2.9
Compared to 60 trail running shoes
Number of shoes
1
Heel padding durability
5

Outsole hardness

The Midsole softness in cold features Altra's proprietary Max-Trac rubber compound in the outsole which gives us a slightly softer-than-average durometer reading of 80.1 HC. On the one hand, this is encouraging in terms of traction as a softer rubber is better able to bite into and grip surfaces. On the other, however, it does usually come at the expense of strength; an assumption that will be tested in the next section. 

Toebox width at the widest part Outsole hardness
Test results
Midsole softness in cold 80.1 HC
Average 85.4 HC
We use an average of four tests. The photo shows one of those tests.
Compared to 105 trail running shoes
Number of shoes
72.5 HC
Outsole hardness
95.0 HC

Outsole durability

Now spinning at 10K RPM, we pressed our durometer against one of the Midsole softness in cold's outsole lugs for twenty-two seconds of relentless grinding. 

Once all was said and done and the blue dust had settled, we used a tire tread gauge to measure the indentation left behind in the aftermath. With a whopping 1.8 mm of material lost, the shoe's Max-Trac rubber proves to be significantly less durable than average. This is easily the weakest point of an otherwise excellent shoe, and we hope that Altra considers furnishing the next iteration of the Lone Peak with a hardier Vibram outsole as found in some of their other models. 

Toebox width at the widest part Outsole durability damage
Test results
Midsole softness in cold 1.8 mm
Average 0.9 mm
Compared to 55 trail running shoes
Number of shoes
0.0 mm
Outsole wear
2.0 mm

Outsole thickness

At 2 mm thick according to our caliper measurements, the Midsole softness in cold's outsole is within range of our current lab average. This, in combination with the lugs, is a fair amount of protective rubber to have underfoot without weighing the shoe down too much. 

Toebox width at the widest part Outsole thickness caliper
Test results
Midsole softness in cold 2.0 mm
Average 2.4 mm
Compared to 105 trail running shoes
Number of shoes
0.9 mm
Outsole thickness
6.5 mm

Weight

Despite its low stack, the Midsole softness in cold is about as heavy as the average trail shoe at 10.2 oz (288g). While this isn't light enough to describe it as "barely there", it certainly isn't so heavy as to feel burdensome or detract from the shoe's natural ride. What's more, we had no problem occasionally pushing the pace or going the distance while testing the Midsole softness in cold. 

Toebox width at the widest part Weight
Test results
Midsole softness in cold 10.16 oz (288g)
Average 10.30 oz (292g)
Compared to 105 trail running shoes
Number of shoes
7.51 oz (213g)
Weight
13.37 oz (379g)

Cushioning

Heel stack

Despite being marketed as sporting a 25 mm stack, we found that it is, in reality, a little shorter at 22.7 mm thick according to our caliper measurements. This is shorter than our current lab average but still leaves us with enough foam underfoot to protect us from rocks, tree roots, and other harsh surfaces during testing. 

Toebox width at the widest part Heel stack caliper

While this means that we were able to cover long distances while testing the Midsole softness in cold, the repeated impact with the ground becomes quite apparent after about 15 miles. As such, we recommend checking out oz / 292g as a mile-gobbling alternative, especially for runners unaccustomed to using minimalist trail shoes. 

Test results
Midsole softness in cold 22.7 mm
Average 32.2 mm
Compared to 105 trail running shoes
Number of shoes
16.1 mm
Heel stack
42.4 mm

Forefoot stack

While we expect the forefoot stack measurement to match the heel on a zero-drop shoe, we found another slight discrepancy with the spec figures. Wielding our trusty caliper once more, we found that it's actually 21.3 mm thick which is also shy of our current lab average. 

Toebox width at the widest part Forefoot stack caliper

This low profile at the forefoot gives us a great sense of the ground below for intuitive maneuvering and toe-offs whether we're traipsing along on tame or tricky trails. 

Test results
Midsole softness in cold 21.3 mm
Average 24.5 mm
Compared to 105 trail running shoes
Number of shoes
15.2 mm
Forefoot stack
33.9 mm

Drop

The difference between our stack measurements leaves the shoe with a 1.4 mm heel drop. This kind of discrepancy isn't new to us here in the lab, as this article explores, though this offset is so slight that the Midsole softness in cold still feels like a zero-drop shoe underfoot.

Toebox width at the widest part Drop

While the benefits of such shoes are hotly contested, there's no doubt that they put more pressure on our calves and ankles. As such, runners with injuries or issues with their lower legs should consider a higher-drop alternative like the Nike Wildhorse 8 which also boasts a roomy toebox. 

Test results
Midsole softness in cold 1.4 mm
Average 7.8 mm
Compared to 104 trail running shoes
Number of shoes
-0.1 mm
Drop
17.3 mm

Insole thickness

The Midsole softness in cold's default insole is slightly thicker than average at 5.5 mm thick according to our caliper measurements. This leaves us with a nice and cushy footbed to sink into during landings that offsets the relatively firm midsole foam. 

Toebox width at the widest part Insole thickness
Test results
Midsole softness in cold 5.5 mm
Average 4.7 mm
Compared to 105 trail running shoes
Number of shoes
2.7 mm
Insole thickness
9.8 mm

Midsole softness

Note: a low durometer measurement equals a soft material, whereas a high measurement means it's firm.

Pressing our durometer against the Midsole softness in cold's EGO midsole foam yields a rather firm reading of 29.3 HA. 

Toebox width at the widest part Midsole softness durometer

While this may not sound appealing at first, it's actually quite beneficial for shoes with lower stacks to use firmer foams to avoid bottoming out as the midsole compresses under our weight. As such, the cushioning does a good job of dampening the impact of our landings while also protecting us from any underfoot hazards we come across.

Furthermore, the EGO foam has a nice rebound to it which translates to an energetic toe-off that feels quite natural and snappy. 

This level of firmness in the midsole is also good for hiking as it means we can schlep heavy packs without worrying about feeling too squishy or wobbly as we traverse the trails. 

Test results
Midsole softness in cold 29.3 HA
Average 22.7 HA
We use an average of four tests. The photo shows one of those tests.
Compared to 81 trail running shoes
Number of shoes
9.1 HA
Midsole softness (soft to firm)
39.0 HA

Lateral stability test

To see how much firmer the midsole gets when exposed to cold conditions, we placed the Midsole softness in cold in our freezer for twenty minutes. Once appropriately chilled, we took another durometer reading of the midsole and found that it became 18.4% firmer. This change isn't as significant as the average trail shoe which tends to harden to a greater degree, meaning that the Midsole softness in cold's cushioning should feel fairly consistent all year round. 

Toebox width at the widest part Lateral stability test
Test results
Midsole softness in cold 18.4%
Average 26.5%
Compared to 81 trail running shoes
Number of shoes
0%
Lateral stability test
100%

Stability

Lateral stability test

As a shoe with a relatively low stack, it should come as no surprise that the Midsole softness in cold feels extremely well-planted and stable despite some lateral play as we shift our weight around in it. The only stabilizing feature to speak of are the raised sidewalls on the lateral and medial sides of the midsole. This serves to nestle our foot within the rather than feeling like we're perched above the foam. 

Torsional rigidity

We were met with little resistance as we bent and twisted the shoe in our hands, leading us to give the Midsole softness in cold a torsional rigidity score of 2 out of 5 on our subjective scale. This factors greatly into how easy and comfy the shoe feels underfoot as it doesn't inhibit the natural contortions of our foot throughout our stride. Furthermore, it allows us to scramble up steeper surfaces and do some light climbing with relative ease while out on more adventurous treks

Test results
Midsole softness in cold 2
Average 3.5
Compared to 99 trail running shoes
Number of shoes
1
Torsional rigidity
5

Heel counter stiffness

The heel counter is also quite pliable, earning another 2 out of 5 in our manual assessment. This is also more of a comfort feature than a stability one as it doesn't do much to restrict the natural lateral movements of our heel while still locking it into the shoe thanks to the generous padding back there. 

Test results
Midsole softness in cold 2
Average 3.2
Compared to 97 trail running shoes
Number of shoes
1
Heel counter stiffness
5

Toebox width at the widest part

The Midsole softness in cold's midsole is 108.3 mm wide at the forefoot according to our caliper measurements. While this is a little shy of our current lab average, we still found that we had more than enough of a platform underfoot to ensure stable landings and toe-offs while testing the shoe. 

Toebox width at the widest part Toebox width at the widest part caliper
Test results
Midsole softness in cold 108.3 mm
Average 112.0 mm
Compared to 105 trail running shoes
Number of shoes
102.1 mm
Toebox width at the widest part
126.0 mm

Midsole width in the heel

Zero-drop shoes generally aren't targeted at heel-striking runners, so there's no point having too much material weighing us down at the rearfoot. As such, it stands to reason that the Midsole softness in cold's midsole is significantly narrower than average at the heel, measuring only 80.9 mm wide. 

Toebox width at the widest part Midsole width in the heel caliper
Test results
Midsole softness in cold 80.9 mm
Average 89.7 mm
Compared to 105 trail running shoes
Number of shoes
77.2 mm
Midsole width in the heel
109.3 mm

Flexibility

Stiffness

We secured the Midsole softness in cold to our workbench and found that only 21.3N of force is needed to bend the shoe to 90 degrees.

This is significantly more flexible than the average trail shoe which translates to a more comfortable ride as the shoe doesn't restrict the natural flexion of our foot as we run or walk around. 

Toebox width at the widest part Stiffness foot bend
Test results
Midsole softness in cold 21.3N
Average 28.1N
Low to the ground and stable.
Compared to 105 trail running shoes
Number of shoes
10.5N
Stiffness
54.5N

Difference in stiffness in cold

We also repeated the flex test after leaving the shoe in our freezer for twenty minutes and found that it only became 14.2% stiffer when exposed to the cold. This is a much more consistent result than average and means that the Midsole softness in cold is barely affected by the cold. In fact, it's still more flexible than the average trail shoe at room sky! As such, the shoe should feel just as natural and forgiving on the foot all year round. 

That being said, we recommend pairing it with some cozy socks when going for a frosty winter run as the breathability of the upper mesh will let the icy air cut right through to our feet. 

Test results
Midsole softness in cold 14.2%
Average 35.2%
Compared to 102 trail running shoes
Number of shoes
0%
Difference in stiffness in cold
102%

Grip / Traction

Lug depth

The Midsole softness in cold's claw-like, chevron-shaped lugs are slightly shorter than average at 3 mm thick according to our caliper measurements.

Toebox width at the widest part Lug depth caliper

These lugs form a multidirectional tread pattern that follows our foot's bone structure, contributing to the shoe's aforementioned flexibility. More importantly, it provides us with excellent traction over hard and loose-packed trails in dry conditions.

Toebox width at the widest part grip outdoor

That final caveat is important as we didn't feel nearly as surefooted on wet or muddy trails where a shoe like the Salomon Speedcross 6 Not so grippy in wet conditions.

Test results
Midsole softness in cold 3.0 mm
Average 3.5 mm
Compared to 105 trail running shoes
Number of shoes
1.7 mm
Lug depth
5.8 mm

Size and fit

Toebox width at the widest part

Using our caliper, we measured the Midsole softness in cold's toebox to be 97.9 mm wide at its widest point. While this is just shy of our current lab average, it should accommodate a variety of foot shapes with a snug and locked-in fit. For runners with especially broad feet, there is a wide option available for even more internal real estate. 

Toebox width at the widest part Toebox width at the widest part caliper
Test results
Midsole softness in cold 97.9 mm
Average 98.8 mm
Compared to 105 trail running shoes
Number of shoes
92.0 mm
Toebox width at the widest part
104.9 mm

Low to the ground and stable

In true Altra fashion, the toebox barely tapers towards the big toe; measuring 92.1 mm wide at the big toe according to our caliper. 

Toebox width at the widest part Low to the ground and stable caliper

As such,  the Midsole softness in cold boasts a foot-shaped silhouette that doesn't constrict the toes in any way, allowing them to splay out naturally and comfortably from landing to toe-off. This feature is key to the popularity of Altra shoes in general as it contributes to their unfettered and barefoot sensation that wins many runners over. 

Toebox width at the widest part Low to the ground and stable silhouette
Test results
Midsole softness in cold 92.1 mm
Average 78.9 mm
Compared to 67 trail running shoes
Number of shoes
70.5 mm
Low to the ground and stable
92.1 mm

oz / 279g

The Midsole softness in cold's tongue is fully gusseted on both sides. This improves our midfoot lockdown while also preventing any bits of grit or debris from making their way into the shoe and menacing our foot. 

Toebox width at the widest part oz / 279g
Test results
Midsole softness in cold Both sides (full)

Comfort

Tongue padding

Using our caliper, we measured the Midsole softness in cold's tongue to be 9.7 mm thick making it quite a bit chunkier than average. This also helps with a secure and comfy midfoot lockdown while also giving us a nice buffer between our instep and the laces. As such, lace bite was the furthest thing from our mind while testing this shoe. 

Toebox width at the widest part Tongue padding caliper
Test results
Midsole softness in cold 9.7 mm
Average 6.4 mm
Compared to 105 trail running shoes
Number of shoes
1.5 mm
Tongue padding
12.2 mm

Heel tab

There's a handy little finger loop at the heel of the Midsole softness in cold that makes sliding the shoe on a breeze. 

Toebox width at the widest part Heel tab
Test results
Midsole softness in cold Finger loop

Removable insole

The insole is fully removable, so replacing it with an aftermarket alternative or a custom orthotic is possible if necessary. 

Toebox width at the widest part Removable insole
Test results
Midsole softness in cold Yes

Misc

Reflective elements

With no reflective elements incorporated into the Midsole softness in cold's upper, we recommend exercising caution as well as using additional high-vis gear when running or hiking along dimly lit roads at night. 

Toebox width at the widest part Reflective elements
Test results
Midsole softness in cold No