The first thing most people notice about any of the shoes in the Altra line is the foot shaped design. This feature alone sets the Altra shoe line apart from most of their peers. The distinctive toe box follows the shape of the foot and allows plenty of room for your toes to splay naturally. The Altra Instinct skirts the boundary of the minimalist running shoe category. The Instinct is definitely minimal because of its zero heel-to-toe drop and anatomically correct shape (custom for women and men) resulting in a nice wide toe box for proper toe splay and the weight is a modest 8.8 oz (249 gr). According to Altra the stack height is 20.0mm (8.5mm EVA, 3mm A-Bound, 5mm Rubber Outsole, 3.5mm insole), I measured them to be 13.7mm + 3.5mm insole = 17.2mm stack height. So this does limit the amount of ground feel or prioproception however the relatively firm A-Bound™ midsole does still allow some ground feedback, but no where as near as much as a VFF or midsoleless shoe. Then again that’s sort of the point! Full review and photos after the jump!

The Upper

As can be seen in the photographs the Instinct upper materials use a very large open weave mesh that is extremely breathable. There is a liner on the inside of the mesh that prevents trail grit and particulates from getting the shoe while still allowing ample air circulation. In addition to the asymmetric lacing, the Instinct utilizes what Altra calls the ‘A’-Wrap (the gray strips at the midfoot) and the HeelClaw™ (gray strips in the heel) to lock your heel and midfoot into the shoe while still allowing ample toe room. A nice feature of the entire Altra line is the minimization of seams. I can’t evaluate how these shoes would handle running sockless, but I’ve encountered no foot discomfort: abrasions, blisters, etc… even with the thin socks I wear. All the Altra line comes with removable, thin foam footbeds. There is absolutely no arch support in the Instinct, the foot bed of the shoe is completely flat and shaped like your foot. So w/o an insole there will be a void between the top of your arch and the food bed. So if you want to “fill that void” use one of the provided foam insoles. The Instinct, along with all the other Altra models, is designed gender specific to accommodate the unique female and male foot forms. In general this means that the female version, called the Intuition, runs narrower in the heel than the male version and the toe box of the female is a bit narrower than the mens. Overall my first impressions were very positive. I’d been so used to slipping my feet into typical road running shoes that ended up crowding my toes together; not so with the Instinct. I think the large open weave mesh will help keep my feet cool during the swelteringly humid summers where I live. Can’t really highlight any obvious flaws with the initial design although from a stylistic point of view the “looks” may be a bit old fashioned. But I like the “old is new” kind of look. It’s a sort of a throwback to the early running shoes. But a few more upper color/designs would be good. Here are some photos of the Altra Instincts, which I picked up in both colorways:

The midsole

The midsole of the Instinct consists of two sandwiched layers. The first layer, immediately below the footbed is what Altra calls A-Bound™ which they describe as an: Environmentally friendly, this energy-return compound is made of recycled materials. Offering extra protection, this unique layer sits directly under the foot to return energy back into each stride. It reduces the impact of hard surfaces while still maintaining ground feedback. Traditional running shoe foam compresses 70-90% while A-Bound™ compresses 2-3x less so it won’t deform over time. The second layer is rather stiff EVA foam, more of the A-Bound™ material but slightly firmer than the first thin layer. If you’re thinking this is a “cushy” road shoe you’d be surprised to learn that the Instinct midsole is far from it. In fact the overall feel is very firm and ground feel, while much reduced, isn’t completely eliminated. I could still notice gravel and road inconsistencies underfoot but the relative thickness of the midsole definitely was doing its job to protect my feet.

The sole

Altra calls it the FootPod™ Outsole and it is indeed one of the most unique road sole designs I’ve ever encountered. The skeleton looking sole is also another conversation starter. This outsole was designed: “For maximum flex and responsiveness, this outsole maps the bones and tendons of the human foot. With canted lugs mapping your foot, this unique outsole provides a natural, all-purpose traction system for a variety of surfaces from road to treadmill to dirt paths.” I can definitely attest that the outsole is definitely adequate for running on most dry surfaces even on some buffer trails I felt comfortable and in control with the simple tread pattern. Now wet and muddy trails would be a different story, but as this is primarily a road running shoe it’s no big deal. I had more than a few wet pavement runs with these shoes and they definitely don’t slip!


As of this review I have tested the Altra Instinct running on paved and gravel roads, on easy dry trails and even on a rubberized track. In short, I’ve tested these shoes on most surfaces it was intended for. At the time of this review I’ve logged almost 200 miles between the two pair of Instincts I own. Here are my impressions: Pavement — Simply superb; what this shoe is designed for. Plenty of traction and the firm cushioning is neither too squishy or bricklike. Most of my mileage in the Instinct has been on pavement or concrete and I can say they’ve performed very effectively. I recently ran the Mercedes Marathon in Birmingham, Alabama in my black pair of Instincts. They felt great the entire way and my feet felt pretty good after. The only thing I noticed was the outside bottom of my right foot felt a little bruised but I think that had more to do with a tough power line workout I did a couple days before the race than from wearing the Instinct in the race. Gravel — Very effective. While I could notice larger chunks of gravel I stepped on (sometimes purposefully just to see) it definitely was muted and not painful. For normal gravel I still could sense the ground so there is some ground feel transmitted due to the hard rubber sole and firm midsole. One very slightly annoying thing about running on gravel is the possibility of getting a small rock embedded in one of the grooves on the bottom of the shoe. Didn’t happen super often, but it happened enough to mention. Non-Technical Trails — Definitely adequate. A lot of my evening runs with my spouse are on a wooded trail behind our home. Never had any issues. The lower profile (stack height) is a plus on the trails. I even ran some on these same trails in less than favorable conditions, mud, standing water, etc… and they still did surprisingly well; slippage was kept to a minimum; definitely better than some other trail dedicated shoes I’ve worn! I never tried the Instincts on some of my more “hard core” routes, but I’d suspect they’d do just fine; probably better in drier conditions. I wouldn’t hesitate to use the Instinct as a go-to hybrid road/trail shoe for races or routes that would require such a shoe. Rubberized Track — Not a whole lot of running here, just a weekly speed session on a local track. As expected the Instinct worked just fine, but then again about any shoe will work well on a cushy rubber track! Just good to know there weren’t any obvious flaws. Casual Wear — Finding myself gravitating to wearing the Instinct around even when non running (one reason I bought two pair!). I think the looks are pretty sharp and they go well with a pair of jeans. Very comfortable.


Above are the two colorways of the Altra Instinct.
In short this is probably the most comfortable road shoes I’ve ever worn in my 20+ years of running. After about 100 miles in each pair of Instincts I can hardly notice any significant wear in the either the uppers or the sole; even the midsole hardly seems compressed to any degree. I’ll caveat this statement with the disclosure that I rotate through A LOT of different shoes. I rarely wear the same pair of shoes on back to back runs. However, since my introduction to the Instinct I’m finding myself in a much smaller shoe rotation that mostly involves this shoe! I’ll also add, in reference to my recent review of the Altra Lone Peak, that I never noticed any slippage in my heel in the Instincts. The overall fit is superb and my toes have never been happier having plenty of room to splay! It should be noted that Altra is a very, very new company and I don’t think they’ve even been making their products for over a year yet. So what you see from them at this moment are akin to prototypes. I can only envision more improvements to come as more and more folks provide feedback back to Altra. As far as my own feedback I’d just have to add that it would be nice if the Instinct was a bit more flexible in the forefoot and a bit lighter. I think that with some cosmetic and material changes the shoe could be made significantly lighter. One other odd thing I noticed about the Instinct; the longer distances I seem to run, the more likely I end up stepping on the inside toe or else kicking the inside toe of the shoe. I think this is because the overall shape of the shoe is curved a bit more inward than I’m accustomed to (to be anatomically correct to one’s foot) and with my running style, especially after I start to really fatigue I tend brush my ankles and calves together. I’ve finished many a run on trails with mud all along the inside of my calves and ankles from kicking myself! Even on road runs I’ll wear a hole on the inward side of my socks and tear up the inside ankle area of my shoes over time. So with the added protrusion of the big toe of the shoe slightly to the inside I have the tendency now to kick that toe (or rub it) with the other foot. Not a big deal and certainly not that noticeable but something to think about. Even my father-in-law who my wife and I bought a pair of Instincts for over the holidays (he has a condition where he needs ample toe room) commented that more than once, while going downstairs, accidently stepped on the opposing toe and almost lost balance! One time he said he stepped on the opposing toe and his foot came right out of the shoe! (He doesn’t lace them very tight most of the time I noticed). Those comments aside, he loves the shoe and, according to my mother-in-law, wears them everywhere. If you’re an avid runner who is dabbling in (or thought about it) minimalism but doesn’t want to sacrifice ample underfoot cushioning this is the shoe for you. Or even if you’re not a big runner but want a shoe with ample toe room that fits well, this is the shoe for you. The fact that it’s zero drop, has enough firm cushioning without going over board and has an ample toe box that allows natural toe splay should be enough! Try it out, you’ll like it!

Official specs and where to get it.

The Altra Instinct is available from AltraZeroDrop.com for $99.99 (shipped free with free returns, no less). It’s also starting to show up around the country at specialty running stores near you! Finally, if you liked this review, share it on twitter (that link will auto-write the tweet for you!)! Here are the official specs on it from Altra, including Altra’s take on sizing the Altra Instinct:
Introducing the first shoe to truly marry the form-improving benefits of a minimalist shoe with the comfort, cushioning and support of a traditional running shoe. The Zero Drop™ platform and innovative foot-shaped design work together to help runners maintain proper running technique and reduce joint impact while freeing their toes to help alleviate foot pain. Trust your instincts and experience the world’s first fully cushioned, foot-shaped, Zero Drop™ running shoe! The Instinct runs slightly short in size. If you are between sizes please go up 1/2 size larger than your regular size. Product Details
  • Weight: 8.8 oz
  • Foot Shaped Design: Male FS-1 Last
  • NRS: Natural Ride System
  • FootPod Outsole Encouraging Natural Motion
  • Quick dry air mesh upper with minimal seams
  • Asymmetrical Lacing, Heel Claw, and A-Wrap for superior fit
  • Drilex Premium Liner
  • Strengthen and Support Insoles
  • Designed to be worn without any insoles for Minimalist Runners or for those who prefer less cushion or more room.