Our verdict

We thoroughly enjoyed the light and minimal feel of the Altra oz / 254g. The shoe's grounded platform and low (alas, not zero) drop made us feel a step closer to being barefoot. Its highly flexible construction followed every movement of our feet, while the toebox offered plenty of space for splaying our toes. While this Altra shoe is not ideal for the rigors of Crossfit, it is a perfect companion for moderate workouts and getting your foot/leg muscles more activated than ususal.

Pros

  • Very grounded low-drop trainer
  • The inner lining, on the other hand, cannot boast the same wear resistance
  • And if you do want a minimalist training shoe but dont need as much toebox space, consider the
  • Solstice XT 2
  • Highly breathable upper
  • It was smart of Altra to cover such delicate mesh with a sturdy overlay on the toebox
  • The inner lining, on the other hand, cannot boast the same wear resistance
  • Add a shoe

Cons

  • Because the Solstice XT 2 follows the foots natural shape, it doesnt have a very wide platform
  • Not a true zero-drop (3.1 mm)
  • Not for casual wear/outdoor use

Audience verdict

86
Great!

Who should buy

Unique features of the Altra oz / 254g make it stand out from many other training shoes.

It's not for everyone but we believe that this shoe will be a great match for athletes who are after the following:

  • a low-drop training shoe that encourages more muscle engagement
  • a grounded, low-stack trainer for better balance and movement control
  • Not for serious Crossfit or heavy lifting
  • Track and XC

Altra oz / 254g review

Who should NOT buy

If your typical workout involves lots of heavy lifting or demanding WODs, the Altra oz / 254g may not offer enough stability and support. We recommend turning to the trusted Midsole softness soft to firm instead.

And if you do want a minimalist training shoe but don't need as much toebox space, consider the However, the heel area of the platform turns out to be narrower than most trainers.

Altra oz / 254g lab test

Cushioning

Heel stack

Measuring the heel stack of the Altra oz / 254g, our caliper showed 23.1 mm. Exactly as stated by the brand.

Altra oz / 254g stack

While this is not considered minimalist, this stack is slightly thinner than average and feels grounded. We experienced a very intimate contact with the floor which made it easier to control our movements and make microadjustments with the feet.

Altra oz / 254g Heel stack
Test results
oz / 254g 23.1 mm
Average 24.8 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
13.7 mm
Heel stack
36.2 mm

Forefoot stack

The forefoot stack measurement, however, showed only 20.0 mm. This is 3 mm lower than the official specs (23 mm).

On its own, we have no problem with a 20-mm stack as it offers a perfect balance of ground feel and cushioning. What bothers us, is the fact that this discrepancy affects the shoe's heel-to-toe drop measurement.

Altra oz / 254g Forefoot stack
Test results
oz / 254g 20.0 mm
Average 18.4 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
10.6 mm
Forefoot stack
27.7 mm

Drop

Calculating the difference in stack heights, we were disappointed with the result. As it turns out, the Altra oz / 254g is not the true zero-drop shoe it is marketed to be.

Based on our lab measurements, it comes in at 3.1 mm! Even though most people won't notice the difference, those who are into minimalist training shoes will. Thus, we must report such discrepancies.

Altra oz / 254g Drop

Athletes who prefer zero- or low-drop training shoes are looking for a more natural positioning of their feet and legs. When your heels are on the same level as your toes, it promotes better muscle activation during the workout, better ankle mobility, balance, and, in the long term, even better posture.

However, zero/low-drop shoes take some getting used to and can even be adverse for people with injuries or some foot conditions. We recommend consulting a podiatrist or a physiotherapist before opting for this type of footwear.

Altra oz / 254g lifting

Test results
oz / 254g 3.1 mm
Average 6.4 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
1.8 mm
Drop
13.4 mm

Midsole softness

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

To prevent wobbliness and compression underfoot, a training shoe must have a firm sole. And the Altra oz / 254g lives up to the expectation.

As our durometer measurement shows, the shoe's foam has a reading of 32.4 HA which is 20% firmer than the average of training shoes.

And yet, we wouldn't recommend lifting heavy (over 300 lbs/135 kg) in the oz / 254g. There is still some compression in the midsole and the shoe is way too flexible.

Altra oz / 254g Midsole softness
Test results
oz / 254g 32.4 HA
Average 27.8 HA
nbsp; |  .
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
17.4 HA
Midsole softness (soft to firm)
41.0 HA

Insole thickness

It may be low-stacked but the oz / 254g comes with a very well-padded insole. Showing 5.6 mm on our caliper, it is among the thickest we've seen in training shoes.

This is a welcome touch of comfort and cushioning as there is not much to rely on in the shoe's firm midsole. 

Altra oz / 254g Insole thickness
Test results
oz / 254g 5.6 mm
Average 3.9 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
1.7 mm
Insole thickness
7.2 mm

Size and fit

Size

Altra oz / 254g is true to size (42 votes).

Not for casual wear/outdoor use?

1 size small ½ size small True to size ½ size large 1 size large
Compared to 37 training shoes
a low-drop training shoe that encourages more muscle engagement
½ size small
Slightly small
True to size
Slightly large
½ size large

Toebox width - widest part

When you lift a heavy bar off the floor or try to balance on one foot, your toes tend to splay and grab a wider area to achieve stability.

That's why it's crucial to have enough space in the toebox and Altra is aware of how important it is.

Altra oz / 254g fit

Just by looking at the Soltice XT 2, we can tell that it is the widest toebox we've seen in a training shoe. It is ready to accommodate the widest feet out there.

Measuring its widest area with a caliper, we got 102.7 mm which is a few millimeters above the average.

Altra oz / 254g Flexibility / Stiffness old method
Test results
oz / 254g 102.7 mm
Average 100.4 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
90.4 mm
Toebox width - widest part
108.5 mm

Toebox width - big toe

a low-drop training shoe that encourages more muscle engagement!

For reference, the Midsole softness soft to firm has a measurement of 81.4 mm and is considered to have a wide toebox. Thus, the Altra oz / 254g earns the proud title of an extra wide toebox.

Altra oz / 254g vs Midsole softness soft to firm Toebox width at the big toe
Test results
oz / 254g 87.3 mm
Average 78.8 mm
Compared to 34 training shoes
a low-drop training shoe that encourages more muscle engagement
65.0 mm
Toebox width - big toe
89.4 mm

Stability

Lateral stability test

The Altra oz / 254g has no stabilizing components. But as a low-stack/low-drop trainer, it comes with some inherent stability.

Torsional rigidity

This Altra shoe bends and twists any way you like. It moves along with the foot with ease but has limits when it comes to lifting heavy weight.

On a 1-5 scale, we rated the shoe's torsional rigidity with the lowest score of 1.

Test results
oz / 254g 1
Average 2.7
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
1
Torsional rigidity
5

Light and barely felt on the foot

There is not much support around the ankle either, so don't expect a firm foothold.

As our push-and-squeeze test shows, the shoe's heel counter is highly flexible, earning only 2 out of 5 on a stiffness scale. 

Test results
oz / 254g 2
Average 2.7
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
1
Light and barely felt on the foot
5

The rest of the upper, except the collar, is very minimally layered to keep the shoe light and airy

Because the oz / 254g follows the foot's natural shape, it doesn't have a very wide platform.

We measured the widest part of the forefoot at 110.5 mm which is the same as the average of training shoes.

Altra oz / 254g Midsole width in the forefoot
Test results
oz / 254g 110.5 mm
Average 110.6 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
101.0 mm
The rest of the upper, except the collar, is very minimally layered to keep the shoe light and airy
117.9 mm

Add a shoe

However, the heel area of the platform turns out to be narrower than most trainers.

With a caliper measurement of 76.7 mm, it is a whole centimeter narrower than average. This is another factor that detracts from the shoe's stability for serious Crossfit and heavy lifting.

Altra oz / 254g Midsole width in the heel
Test results
oz / 254g 76.7 mm
Average 87.3 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
76.5 mm
Add a shoe
97.4 mm

Very grounded low-drop trainer

The Altra oz / 254g is one of the most flexible training shoes we've tested. Thanks to the Innerflex technology, its midsole bends exceptionally well to mimic a barefoot experience.

Doing planks, lunges, sled pushes, stretches, and other exercises, we never faced resistance from this Altra shoe.

Altra oz / 254g Very grounded low-drop trainer

In the lab, we measured how much force it takes to bend the oz / 254g to a 30-degree angle. Requiring only 7.3N, this shoe is in fact 35% more pliable than the average trainer!

Altra oz / 254g innerflex

Test results
oz / 254g 7.3N
Average 11.0N
Compared to 19 training shoes
a low-drop training shoe that encourages more muscle engagement
6.0N
Flexibility <> Stiffness
19.7N

Weight

Lightness is one of this Altra shoe's main virtues. Doing all sorts of agility work and cardio is a blessing in this trainer! 

Tipping the scale at only 9.0 oz (254g) in a men's US size 9, it is among the lightest in our roster. Basically, this shoe is only second to minimalist trainers.

Paired with its low stack and drop, such a light weight makes the oz / 254g feel barely present on the foot.

Altra oz / 254g Weight
Test results
oz / 254g 8.96 oz (254g)
Average 10.76 oz (305g)
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
6.38 oz (181g)
Weight
13.83 oz (392g)

Breathability

We weren't worried about breaking some sweat in the Altra oz / 254g. The shoe's mesh upper stayed wonderfully ventilated the entire workout, letting the air in and out of the shoe.

Our personal experience was also backed up by a smoke-pumping machine test. The smoke effortlessly passed through the fabric in the toebox and other parts of the shoe.

It all made sense when we hovered the shoe's half-cut upper over the light. It showed how thin the mesh actually is and how large its breathing pores are.

Altra oz / 254g microscope

We also grabbed our microscope for a close-up view. It clearly shows the varying thickness of threads in the shoe's fabric. Areas with thinner threads make up the ventilation pores.

Heel counter stiffness!

Altra oz / 254g microscope upper

Test results
oz / 254g 5
Average 3.6
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
1
Breathability
5

Durability

Toebox durability

Checking the shoes outsole hardness, we were a bit worried about its soft nature.

To test its abrasion resistance, we equipped ourselves with a Dremel and drilled the center of the toebox for 12 seconds. For the record, the speed (5K RPM) and pressure (3.2N) remained consistent.

The oz / 254g passed our durability test with flying colors!

Altra oz / 254g Toebox durability test

Sure, the Dremel left a scuff but the overlay didn't let the tool get to the mesh. And that deserves a high score of 4 out of 5 for toebox durability.

Test results
oz / 254g 4
Average 2.5
Compared to 30 training shoes
a low-drop training shoe that encourages more muscle engagement
1
Toebox durability
5

Heel padding durability

Another reason why we think its best to keep the Altra Solstice indoors is its outsole thickness.

After a very short bout of drilling (4 seconds), the shoe's heel padding got significantly damaged.

On a scale from 1 to 5, where 1 is the absolute worst, we rated the shoe's durability in this area as 2. Altra could do better here!

Altra oz / 254g Heel padding durability test
Test results
oz / 254g 2
Average 2.5
Compared to 28 training shoes
a low-drop training shoe that encourages more muscle engagement
1
Heel padding durability
5

Outsole hardness

Checking the shoe's outsole hardness, we were a bit worried about its soft nature.

With a durometer measurement of 71.0 HC, it turned out to be 20% softer than the average training shoe. Will the Altra oz / 254g have the same capacity to last as the other trainers?

Altra oz / 254g Outsole hardness
Test results
oz / 254g 71.0 HC
Average 83.0 HC
nbsp; |  .
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
71.0 HC
Outsole hardness
94.5 HC

Outsole durability

Our surefire way to tell is to drill the shoe's outsole with a Dremel.

This time, we set the tool's speed to 10K RPM and extended the drilling time to 22 seconds. Luckily, the Altra's rubber outsole persisted!

Showing only 0.9 mm of damage, it held up just as fine as the other training shoes (even those with firmer outsoles!).

Altra oz / 254g Outsole durability test

This fact made us confident about the shoe's outsole longevity in the gym. However, we still don't recommend it for casual wear outside the gym because soft rubber will wear out faster in that scenario. 

Test results
oz / 254g 0.9 mm
Average 1.1 mm
Compared to 26 training shoes
a low-drop training shoe that encourages more muscle engagement
0.0 mm
Outsole wear
2.0 mm

Outsole thickness

Another reason why we think it's best to keep the Altra Solstice indoors is its outsole thickness.

With a caliper measurement of 3.1 mm, it is slightly thinner than average but is more than enough for gym use.

If you need a shoe for outdoor training sessions, consider the oz / 254g instead (4.1 mm of outsole thickness).

Altra oz / 254g Outsole thickness
Test results
oz / 254g 3.1 mm
Average 3.6 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
2.1 mm
Outsole thickness
5.1 mm

Misc

Grip / Traction

The shoe's grip never let us down on the gym surfaces. Because its outsole rubber is softer than average, it bites onto the ground a little better as well.

Altra oz / 254g outsole

Pair that with the shoe's low stack and multiple flex grooves, and you feel like you're grabbing the floor with your feet.

Tongue padding

The tongue of this Altra shoe is lightly padded with 6.0 mm of foam. This is an average amount of padding for training shoes.

Altra oz / 254g Tongue padding

The rest of the upper, except the collar, is very minimally layered to keep the shoe light and airy.

Test results
oz / 254g 6.0 mm
Average 5.4 mm
Compared to 41 training shoes
a low-drop training shoe that encourages more muscle engagement
1.0 mm
Tongue padding
10.4 mm

Tongue: gusset type

The tongue of this Altra shoe is not gusseted but considering the minimalist design of this trainer, we never had issues with the lockdown or bunching in its upper.

Altra oz / 254g Tongue: gusset type
Test results
oz / 254g None

Heel tab

Altra oz / 254g Heel tab

Removable insole

The oz / 254g comes with a large enough loop hole (yes, thank you!) which is very handy for getting the trainer on with little effort.

Altra oz / 254g Removable insole
Test results
oz / 254g Yes