Summary

We spent 7 hours reading reviews from experts and users. In summary, this is what runners think:

7 reasons to buy

  • Footgear experts were astonished by the TerraFlex’s superior surface traction.
  • This shoe racked truckloads of praises from numerous sources for being fantastically comfortable.
  • Professional reviewers were deeply impressed with the shoe’s spacious enough toe box.
  • Its extreme lightness left many owners in awe.
  • Several wearers swore by the short break-in period of this shoe.
  • The TerraFlex mesmerized footwear critics with its Xero-drop sole. Its non-elevated heel helped them pull off maneuvers with little-to-no constraints.
  • A couple of testers commended the footwear’s outstanding flexibility.

2 reasons not to buy

  • Some users thought the stitching of the shoe was done poorly because it looks cheap and comes undone easily.
  • Less than a handful of consumers found an issue with the shoe’s fat laces. One of them thought that they were too bulky to tie easily.

Bottom line

Xero Shoes designers should be applauded for successfully making the TerraFlex monumentally comfortable and light. They also deserve a pat on the back by giving the shoe a remarkably grippy outsole and a satisfyingly roomy forefoot space. However, they probably overlooked the gear’s overall sizing as people lambasted it for running small. Nevertheless, those who have the time and patience to get the TerraFlex in the right size are bound to experience the expansive outdoors with great freedom.

Facts

Rankings

A top rated Trail running shoe
A popular pick
It has never been more popular than this May

Expert Reviews

94 / 100 based on 42 expert reviews

  • 99 / 100 |

    Feel the earth: A review of Xero TerraFlex running shoe

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    I am a 42-year-old runner, about 170 pounds and 6’ 1” tall. I race all distances, from 5ks to Marathons, and spend at least half of my year training for an upcoming marathon.

    At first glance

    The TerraFlex is billed as a high performance, true minimalist trail running shoe. At first glance, it looks like an ordinary trail shoe – good grip, lots of rubber and cushioning around the ankles – but upon closer inspection, it becomes apparent that this is a minimalist shoe. Very flexible, wide toe-box, zero drop, and only 3 millimeters separate your feet from the ground when the insole is removed.

    Xero Shoes has done an impeccable job of adding the comforts of maximal trail shoes but maintaining the integrity of a true minimalist shoe.

     

    Shoe Length

    The Xero Shoes website advises purchasers to select a half-size larger than they usually wear since their shoes typically run a little small.

    I am a size 12 and since they did not have 12 ½ available, I just went with my normal size 12. While my toes do come near the end of the shoes, by using a heel-locking shoe-lace knot, I can keep my feet from pounding the toes.

    In addition, the very purpose of training in minimalist shoes is to re-train your feet to land correctly, which should ease the pressure on the toes and force more of a foot-strike in which the body weight is directly above the feet. So, shoe length is not a problem for me.

    Laces

    The shoe laces seem to by typical hiking shoe round laces. Nothing too fancy about them.

    The shoes do have instep, upside-down “V” straps that are not stitched down to the sides of the shoes. This allows the laces to cinch down the mid-foot a little tighter.

     

     

    Also, I am thankful for the additional eyelet at the top which allows a heel-locking tie, as well as making sure the laces do not rise above the tongue of the shoes.

    Toe Box

    The toe-box is extra-wide, resembling an Altra shoe toe box. Toes are able to flex and splay as needed, which ultimately allows the feet to strengthen.

    Arch Support

    As most minimalist shoes do, the Terra Flex does not provide much in the way of arch support.

    This may seem backward, but if our arches are to be strengthened and take the shape they were originally created to take, they need to learn how to function without a lot of support. Again, this absence of support will ultimately strengthen the arches.

    Heel Support

    The heel of the shoes is very plush and comfortable. In addition, true to the inspiration of the Huarache design, Xero Shoes has added a strap that connects from the top of the laces all the way around the back of the heels, for support. Both the heel strap and inverted “V” instep straps are highly reflective for safety.

    Upper

    The upper part of the shoe is very soft and plush. Most of the upper is made of breathable mesh.

    Midsole/outsole

    The key word here is “flexibility.” As a true minimalist shoe, the Terra Flex is extremely flexible, while providing some outer lugs for traction. The midsole is particularly minimal, with a removable 2mm cushioned insole for an even more barefoot-like feel.

     

     

    For these miles, I entered the Terra Flex shoes into a marathon training week. I had to travel, so a few runs were on the treadmill, but the other runs included recovery runs on trails, hill repeats on a combination of trails and streets, and covered every other kind of off-road terrain, including mud, water, dirt, grass.

     

     

    I want to share a few general observations before I get into the performance details:

    1. Xero Shoes has figured out the precise way to provide a thin, very flexible outsole that provides protection from rocks, acorns, and twigs.
    2. This flexible outsole allows my feet to contour with the terrain, which prevents ankle and knee twisting on uneven surfaces.
    3. Going sock-less is surprisingly doable with these shoes if that suits you.
    4. The upper part of the shoes is robust. The mesh, combined with leather and rubber on the outer portions of the shoes means your feet are protected from whatever you may encounter on the trails.
    5. The thickness of the upper has a downside. While the shoes evacuate water relatively quickly during the run, the thickness of the upper mesh requires some extra time for the shoes to dry out completely.
    6. Lastly, the Terra Flex seems to have larger lugs on the front part of the outsole than the rear portion, which almost seems to place the shoes in a heel-to-toe rise. My heels seem to sit closer to the ground than my toes do. This isn’t necessarily a bad thing, but something to take into consideration.

    Performance

    The Xero Shoes Terra Flex running shoes are adaptable to every terrain, including extreme mud and water. The breathable upper mesh allows for the clearance of any water that might find its way into the shoes. Any mud or debris that may stick to the bottom of the shoes typically sloughs off after several meters.

    The outsole lugs combined with the flexible sole provide extreme traction on every surface. This traction and flexibility allow the shoes to be used for every workout, including 400-meter hill repeats at 10k pace.

    Since I ran in these shoes for speedwork, slow recovery trail runs, and a 15-mile run, I can confidently say that these shoes provide a versatile choice for every kind of workout.

     

    Expected lifespan

    As with all Xero Shoes, the Terra Flex come with a 5,000-mile sole warranty. I will let you know when I reach that! After 50 miles, I see no reason to think these won’t last a very long time.

    Pros

    • Maximum comfort, minimal shoes
    • Great foot protection from sole and upper
    • Flexible but firm

    Cons

    • Take too long to dry out
    • Heel-to-Toe rise

    Final thoughts

    If you are looking for a versatile minimal running shoe with a barefoot-like feel on every terrain, this shoe is for you.

    Unlike other minimal shoes, you can actually throw the Terra Flex into speed workouts and expect hit your pace marks. These shoes are extremely comfortable, flexible, and provide protection for your feet while allowing them to fully flex and maintain strength throughout the run.

  • 85 / 100 |

    Xero TerraFlex: The Nothing that is…

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    The TerraFlex from Xero Shoes initially presents itself as an unassuming trail shoe. However, the TerraFlex is packed with features that make it deserving of a closer look for those considering a minimalist running shoe that can handle a variety of terrain.

     

     

    When the minimalist running shoe movement took off it just made sense. Our feet have been anatomically sculpted through thousands of years of evolution to move and run unencumbered by stiff, clunky footwear. However, those of us who lack the true grit of the barefoot purist need a little something extra between our feet and the world.

    Stats

    Weight: 9.6 oz
    Drop: 0 mm
    Stack: 4-6mm
    Category: Trail Running/Hiking Shoe

    First Impression

    When I tried on the Xero TerraFlex I was initially pleased with the roomy toe box. The shoe offers the toes ample room to splay out and connect with the ground, but not too much to feel sloppy.

    These shoes feel very natural and light. With a limited number of brands offering true zero-drop shoes, or in this case, Xero-drop, the low to the ground feel is very welcomed. These shoes were comfortable right out of the box.

    You could say that the Xero brand needed zero break-in time. My first 5 miles in these shoes were a complete joy. The zero drop and minimalist style of the sole encourage the running form to return to its natural state of forefoot striking. This might take some getting used to for heel strikers.

    Fit

    The TerraFlex has a very comfortable ergonomic fit that cradles the foot nicely. As mentioned the toe box has a more liberal fit with lots of space to do what your toes need to do.

    With a trail shoe, I feel that this is important. Rather than plodding along the trail, your feet are allowed to build connections and relationships with the trail surface.

    The ankle collar is amply padded. This offers needed protection in an area where your foot is very exposed to rocks and other debris. The inverted V strap feature is a unique innovation on Xero shoes. It's adjustable and helps you to snug up the heel counter very nicely.

     

     

    My foot felt very secure in the shoe. The tongue is very soft and works well with the lace cage to hold your foot firmly while not putting unwanted pressure on the top of your foot.

    Performance

    The FeelTrue sole of the TerraFlex is very thin and when you remove the 2mm insole you get closer to a barefoot feel. The shoe is designed to feel comfortable without the insole and even when worn without a sock it feels good. I tested this shoe in some colder weather.

    The cushioning of the upper provides some warmth which is nice compared to the extreme minimalist shoes l have run in like the Vibram Fivefingers. The TerraFlex FeelTrue® rubber stays nice and supple. One of the worries that I had was that the thin layer of rubber would get too rigid in cold weather but this was not my experience.

    The shoes weigh in at 9.6 oz and that is light but not as light as some other minimalist shoes on the market. With that said the shoes do offer more protection on the uppers and the sole than some other brands do, and a little more weight is the tradeoff. Either way, 9.6 oz is a really light shoe, and you can feel this as you ease down the trail.

    The reflective logo and stripe on the bands of the shoe are nice added safety features. I end up doing a lot of my running at night or in the early morning out of necessity, and any edge that I can gain over being struck by a car is a welcomed advantage.

    My biggest concern with the Xero TerraFlex was the tread. I was hoping for a slightly more aggressive tread pattern.

     

     

    The shoes had good traction on most surfaces but once things got really technical I found that the shoes needed a little more bite than they had. I should qualify that by saying that by technical I mean very steep, loose and rocky trails in western Montana.

    On moderate single track and rolling terrain, these shoes performed super well and had amazing grip on wet surfaces. My most recent run was on snow-dusted pedestrian paths and the grip of the Xero shoe was superlative.

    One other thing that bothered me, which is minor, was the laces. The Xero shoes come with a standard braided lace. I had difficulty with these slipping and becoming untied and as a result, I had to double knot them. A minor concern but there are so many techy laces out there these days and these shoes could stand for an upgrade.

     

    Durability

    Xero boasts an incredible 5000-mile warranty on their proprietary FeelTrue Rubber sole. This got my attention since conventional wisdom retires the average running shoe at 500-700 miles. The Xero warranty policy is stated below.

    ¨If you wear your FeelTrue® outsoles (or FeelTrue® section of Z-Trail) down to less than 1mm thick at the ball or heel of the foot (not an edge), we’ll replace them with the same product for the following price: 60% off MSRP (full, non-sale, listed, retail price) for the product, plus shipping.¨ https://xeroshoes.com/shop/terraflex/terraflex-men/

    The insanely flexible nature of the shoe made me concerned that fractures at stress points might develop over time, but with 123 miles on these shoes, I have yet to notice any sign of unusual cracking or stress marks. It is unusual and impressive to be able to squeeze this much of a shoe between two fingers.

     

     

    The upper fabric of the shoe is durable and pliable. The thickness adds a lot of plush comfort but unfortunately holds onto water longer than I liked.

    The reinforcement that is stitched around the toe area is a nice touch compared to other shoe brands that glue on the reinforcement and should add extra life to that area of the shoe.

     

    Pros 

    • Light and responsive
    • Vegan-friendly materials
    • Good foot protection
    • 5000-mile warranty

    Cons

    • Less than aggressive tread
    • Standard laces
    • Takes too long to dry out

    Overall

    Ultimately, I was pleasantly surprised by the Xero TerraFlex. This light, minimalist shoe is a well-rounded balance between a barefoot slipper-style shoe and a dedicated trail running shoe.

    A zero-drop platform with a low stack height makes it a very natural and responsive running shoe. The TerraFlex achieves a happy medium of responsivity on the trail, natural fit, and lightweight performance.

    If you are someone who's looking for a minimal trail shoe but are not quite ready for the full-on barefoot shoe, the Xero TerraFlex is definitely worth checking out. At an MSRP of $100.00, it is well worth the money. 

  • 100 / 100 | Xero Shoes | Level 4 expert

    I hope you give 'em a try as well! They're really great.

  • 100 / 100 | Xero Shoes | Level 4 expert

    Looks like they will hold up to anything you throw at them. Great shoe!

Become an expert
  • The Xero Shoes TerraFlex is a vegan-friendly footgear designed for off-road excursions. Its interior is barefoot friendly, which means it can be donned with or without socks on.
  • Fabric straps are engineered at the shoe’s heel and instep. The ones at the heel grant additional support, while those covering the instep provide a more secure fit around the midfoot zone.

The TerraFlex is a low-cut running shoe for men and women. It is listed in half and whole sizes in standard width. Its lace-up closure with adjustable instep straps enables wearers to get a customized lockdown. For natural toe spreading, the footwear is built with a wide toe box. This running gear, according to Xero Shoes, runs small. Purchasers are advised to size up to get the most accurate fit in it.

This running gear uses a company-exclusive rubber outsole called FeelTrue to help prevent users from slipping and sliding off tricky surfaces. It is also used in the Xero Shoes Prio and its grip effectiveness is primarily linked to its many V-shaped lugs. It comes embedded with Barefoam—a 3 mm thick layer that doubles down on underfoot protection and comfort.

A removable insole with a thickness of 2 millimeters is nestled right on top of the TerraFlex’s rubberized outsole. It offers extra cushioning and additional underfoot support. It also grants breathability thanks to its perforated underside.

Breathable mesh and stitched-on overlays form the Xero Shoes TerraFlex’s below-the-ankle upper. Its front tip is built with a durable toe bumper called Tough Tek for extra forefoot protection. Its midfoot and heel regions are engineered with straps that reflect light in the dark.

The shoe’s classic lacing system is made up of round laces and combination eyelets. The second and fourth pairs of eyelets are seamlessly integrated with the footwear’s reflective straps.

Author
Jens Jakob Andersen
Jens Jakob Andersen

Jens Jakob is a fan of short distances with a 5K PR at 15:58 minutes. Based on 35 million race results, he's among the fastest 0.2% runners. Jens Jakob previously owned a running store, when he was also a competitive runner. His work is regularly featured in The New York Times, Washington Post, BBC and the likes as well as peer-reviewed journals. Finally, he has been a guest on +30 podcasts on running.

jens@runrepeat.com