Barefoot is out; cushioning is in.  But what if you could combine all the great elements of barefoot running with the comfort of cushioning?  You’d have a shoe that looks a lot like the Altra One2 Squared.

Altra One2 Features:

  • Weight: 5.9 oz
  • Stack height: 23mm in heel and forefoot
  • Fully cushioned Zero Drop platform
  • Foot-Shaped Toe Box
  • Midsole: Ultralight EVA/A-Bound blend
  • FootPod Outsole
  • Insole: 5mm contour footbed
  • Lightweight quick dry air mesh upper
  • Asymmetric lacing
  • 2 color options
  • MSRP $100

altra the one squared running

Altra One2 Delivers Cushioned Minimalism

Altra was a relatively late arrival to the minimalist bandwagon, but they shrewdly staked out the sweet spot where the majority of runners – and accordingly, the shoe industry as a whole – would ultimately settle: making well-crafted shoes that combine all the biomechanical benefits of natural running with a modest amount of comfort and protective features to keep going for miles on end.

In just a few years of existence, the company has jettisoned its purely minimal offerings (anyone remember the Adam?), but stuck with several minimalist features that can be incorporated in to traditional shoe design.  And the One Squared is an example of just how brilliant this combination can be; it’s a remarkably comfortable, amazingly lightweight, and highly flexible road shoe built upon a zero-drop platform that allows for natural biomechanics without compromising speed or performance.

Altra One Squared Running Shoes

Although the One Squared is an update of Altra’s previous One model, it has so many design changes that the name is one of the few similarities remaining.  Two particular specs are telling indicators of the current industry trend: although the stack height is higher – 23mm compared to 17mm – the overall weight is almost 20% lighter, at 5.9 oz compared to 7.3oz.  (For a point of reference as to how light that is, recall that Vibram’s original KSO weighed in at 5.7 oz.)  The weight savings is possible primarily thanks to Altra’s Ultralight EVA midsole material, and also due to the removal of outsole rubber on the majority of the bottom surface.

The combination of outsole and midsole componentry are referred to as a Natural Ride System, which is a fancy way of saying Altra does everything they can to make sure the structure of the shoe interferes as little as possible with natural motion of the foot.  Deep longitudinal grooves in the midsole provide natural anterior-posterior flexibility.  Metatarsal pods along the width of the forefoot are built to mirror and flex with the bony structure of the foot.  And an anatomic toe box allows the toes to splay naturally on foot strike.

Altra One Squared Running Shoes Review

One drawback of the new outsole design that became apparent during testing was a substantial amount of wear right smack in the middle of the metatarsal heads after about 50 miles of running.  High abrasion rubber is strategically placed on the lateral heel and along the first metatarsal, but for runners who land consistently on their middle foot, a bit of rubber across the metatarsal heads would improve durability of this shoe significantly.

Altra One Squared Upper

The upper of the One Squared is redesigned as well, with a softer, more closed mesh pattern than its predecessor; this makes the new version slightly warmer and less breathable, but not so much to affect performance.  The tongue and lacing system is now asymmetric, creating less pressure on the top of the midfoot.  Overall comfort of the shoe is outstanding, from the upper to the smooth and responsive ride, even for runs of several hours.

The Good:

  • Super lightweight
  • Highly flexible
  • “Sweet spot” combination of comfort and natural motion

The Bad:

  • Outsole EVA vulnerable in key midfoot strike area
  • Poor outsole traction if venturing off road

Bottom Line: Altra One2

With an almost ideal combination of light weight, deluxe comfort and high performance, the One Squared represents the best elements of where modern running shoe design should be.

Buy Now: Available at

About Author

Donald is a physical therapist, ultrarunner, barefoot aficionado, and father of three with more than 20 years of experience in endurance sports. When he's not training for ultramarathons, he enjoys hiking or slacklining with his family in Monterey County, CA.

Leave A Reply