We spent 6.7 hours reading reviews from experts and users. In summary, this is what runners think:

8 reasons to buy

  • The shoe had an efficient water drainage system, a reviewer stated.
  • A couple of users praised the grippy outsole of the Primus Trail SG.
  • Some wearers pointed out that the toggle lace feature enabled a convenient use.
  • The shoe excelled on wet terrain, including grass and soil, a runner mentioned.
  • A lot of consumers appreciated the lightness of the shoe’s weight.
  • There was enough room for a comfortable toe splay, a customer remarked.
  • Many buyers thought this running shoe was worth its price.
  • The outsole seemed to be durable despite its thinness, a runner cited.

3 reasons not to buy

  • The collar was too high and was continually hitting the ankle bone, a user commented.
  • Several runners disliked how the Vivobarefoot Primus Trail SG was too broad to give a relaxed feel.
  • A wearer said the shoe was not comfortable when worn without a sock.

Bottom line

The Vivobarefoot Primus Trail SG garnered mostly positive reviews from its users, with comments that focused on the shoe’s performance and its numerous features that proved to be effective. There were only a handful of criticisms that stemmed from fit and sizing issues.


Expert Reviews

83 / 100 based on 13 expert reviews

  • 65 / 100 |

    Vivobarefoot Primus SG: A blisteringly hardcore barefoot trail running shoe

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    The Vivoabarefoot Primus SG is one of the most rugged barefoot trail running shoes on the market.

    The Primus SG feels low profile and nimble, but it certainly protects your feet from the elements. Unfortunately, the Primus SG is not at all comfortable for my feet.



    • Barefoot ride
    • Great traction
    • Great protection


    • Uncomfortable upper
    • Heavy
    • Aesthetically unattractive
    • Expensive

    Marketed Statistics

     Weight  17.6oz (false)  Terrain  Trail
     Heel to Toe Drop  0m  Support Level  Neutral
     Price  $160    


    The Primus SG has a standard fit in the heel and midfoot and a wide toe box.

    The wide toe box allows your toes to splay: the natural way of running. Although the toebox is wide, it is quite low volume. My feet always feel the upper rub against them while running.


    Upper material

    The Primus SG does not have a tongue or heel cup; rather, it has a stretchy upper that wraps around the foot.

    The Primus SG has a speed lacing system. The laces are round and narrow, and they don’t stretch at all. These are some of the least comfortable and secure laces I have ever experience.

    The wide fit means that I have to really cinch the laces. The laces don’t provide a good fit, they cause pressure points, hot spots and really irritate a vein on the top of my foot.

    They are so uncomfortable that I would rather wear them loose, even though my feet slide around the shoe. The heel collar bites into my ankle and causes nasty blisters.   



    The toe box is constructed with a lightly perforated mesh. The upper is decently breathable, while still keeping out debris. The upper is not soft, so you need to wear socks when wearing this shoe.

    Toe Bumper

    The Primus SG has a heavy duty toe bumper. Although most runners don’t kick rocks while they run in barefoot shoes, if you do bump a rock, your foot will not feel it.


    The Insole

    The Primus SG is built with a fixed insole. The shoe also comes with a set of additional insoles if you feel that you want a slight touch of cushioning.



    The Vivobarefoot logo is printed on the outside of the shoe in reflective material. This improves visibility while running on roads at night, but since this is a trail shoe it doesn't make a big difference.


    There are three main criteria for any barefoot running shoe outsole: It must be flexible, durable and provide good traction.

    The Primus SG fulfills all three criteria. The outsole is a sheet of sticky durable rubber. Protruding from the outsole are dozens of multidirectional chevron-shaped lugs. The lugs face forward in the forefoot and rearwards in the heel to maximize traction.



    The Primus SG goes overboard with traction. When running in a barefoot shoe, most runners don’t need as much traction since they tread lightly and run cautiously.

    The aggressive outsole provides additional unneeded traction and makes the ride harsher. Running in snow and extremely sloppy conditions is the exception. The outsole is not as flexible as the standard barefoot shoe, but it is still plenty flexible.

    Best Uses

    The Primus SG works best as a barefoot trail running shoe for very sloppy terrain; however, I cannot recommend this shoe to anyone because the upper caused my feet so much grief. Personally, I would always choose a different shoe for every run.

    That does not mean the shoe is universally bad. Some may find that the Primus SG fits them perfectly. Anyone who wants a barefoot ride, along with a ton of protection should check out the Primus SG. The Primus SG could be a fun shoe if it fits your feet well.


     Shoe Brand  My Size
     Vivobarefoot  12
     Merrell  12
     Brooks  12.5
     Saucony  12
     Altra  12
     New balance  12
     Nike  12.5
     Scott  12.5
     Adidas  12.5
     Hoka One One   12.5
     Vibram  12
     Inov-8  12.5

    Vivobarefoot Primus SG Vs. Merrell Trail Glove 4

    The Trail Glove has less protection and less traction compared to the Primus SG, but it has all that a barefoot trail running shoe needs.

    Additionally, the Trail Glove is much more comfortable, lighter, and far less expensive. For most runners, the Merrell Trail Glove is a much better option for barefoot trail running shoes.


    The Primus SG is a high-quality shoe, but its construction just doesn’t make much sense. A barefoot running shoe doesn’t need a ton of protection or traction since runners tread carefully while running barefoot.

    If your feet are very different to mine, and this shoe is comfortable, it is a high performing shoe for running and hiking on a very sloppy terrain.

  • 85 / 100 |

    The Vivobarefoot Primus Trail SG (Soft Ground)

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    A shiny red shoes for trail running from the Vivobarefoot family!

    To start off, I was very impressed with the feel of lightness and the super aggressive tread outsole. I kept looking at all those details for a good period of time, trying to figure out what is the deal with these guys.

    Right out of the box, you can see there a set of inner soles and extra kit of laces if you don’t want to use the bungee cord system, sweet!


    Shoe specifications

    minimalist trail shoe with very aggressive outsole, as can be seen with the sharp treads down there. The drop is 0 mm, almost zero thickness, with only the treads jutting out.

    These shoes are very specific and you either hate or love them. The soft ground is the type of soil that you need to appreciate the performance of these shoes.



    We tested it in various types of ground: volcanic soft sand, thick grass, mud potholes with rivers beds, hard soil tracks. The feelings on these pack of terrains highly varies.


    What we did as a first test was to take the shoes to a very high altitude place with a very soft sand playground, volcanic sand to be more specific and then try to get fun running. 

    Let me tell you that these shoes are all about traction and grip on a dry surface. You'll fall in love with the gripping cornering in this kind of soil.

    That said, you can jump with confidence in soft ground with this shoes and it won’t slide down. Nice!



    Then we ran for a couple of hours on this mix of soft sand and hard pack fire road. We can notice the difference right there.

    The shoes became a mix of hard feelings, no cushion, no nice gripping, a bit of side of sliding if you put an effort running. The bungee cords lacing works perfect but the wrapping of shoes around the ankle can be annoying, sad.

    The result was a bit of pain around the ankles, not nice guys!



    Next test was a field with thick grass like the one for cows, lambs or so; the kind of grass that you don’t want for the running day. Again, we fell in love with the performance of the shoes.

    We laced a bit lose to find out if we can avoid the ankle pain from previous running sessions. While that works, the result is a lack of confidence due to side sliding of the shoes in certain circumstances.

    Nevertheless, the overall feeling was good in the grass field. 

    What's next?

    We kept running our schedule in a mix of terrain: hardpack fire roads, rocky river beds, and we found out a particular (because of the season of the year) muddy trail.

    We love the performance of the shoes on that terrain. It simply rules over the muddy soil! It has great grip and superb water draining capabilities. 

    If you care about cleaning shoes, these are particularly easy to clean. All you need to do is to take this out for a bath after your run.


    I did a quick inspection of treads, they don’t look worn after a good charge of kilometers. That's in comparison to other brands that tend to wear faster than you expect.

    On the side of shoes, there are unnoticed words that said eco rubber. Kudos to that!

    The upper is a made up of very light mesh that looks strong. While our feet tend to slide out of the shoes, the really shining thing about this shoe is the inner sole. I will say that this is the best thing that I found in this pair.

    Literally, you can see through the insole which is built to drain water fast very fast! 



    There is enough room for the foot fingers, no tight thing here.

    The lacing system is pretty similar to other brands in the bungee cord fashion. It's very effective & keeps the shoe lightweight. Don't hold or laced too tight as it hurts after a number of hours running.


    • Lightweight
    • Good looking red shoes
    • Nice lacing system
    • Great tread shape
    • Grippy outsole
    • Light, breathable insole


    • Can’t run in a loose green rocky carpet 
    • Lace system can hurt
    • No cushion for this trail shoe
    • A very specific shoes for a very specific terrain         
  • 83 / 100 | | | Level 1 expert

    ...but, all in all, I'm very pleased with them, the shoe from this very first outing...

  • 92 / 100 | Morten Lidegaard | Level 2 expert

    Their appearance give them away as being real beasts for the trails. They are low (as in no cushioning as they are made for "barefoot" running); Weight is about 285g for my size 9UK(43); They've got large multi-directional lugs on the outsole for improved traction in the mud and on loose ground, and is made from some tough rubber for a sticky grip; They've got a quick-lacing system which works pretty well, however, they do also come with normal laces if you prefer these; The toe-box is as expected large with plenty of room for your toes to spread out and feel free; The upper front-mesh provides great ventilation without letting dirt into the shoe; The structure around the heal/ankle is made as a tight fitted collar keeping dirt from entering the shoe; They are quick draining through the mesh on the sides; And they are relatively quick drying when you have soaked them in your free shoe-wash on your way back home

Become an expert
  • Vivobarefoot introduces the Primus Trail SG, a running shoe that is ideal for “soft ground,” which, in this case, translates to muddy and loose trails. It is a one-of-a-kind, barefoot-type apparel with a water-resistant property. This running shoe is suitable for neutral pronators or those with a medium to high arch.
  • The Primus Trail SG prides itself on being 100% vegan-friendly, as the shoe is built using animal-free processes and materials.
  • It has a breathable mesh upper that keeps the foot feeling fresh and ventilated. As a water-resistant shoe, it includes quick drain zones that efficiently purge water and discourage moisture retention.
  • The shoe has zero cushioning, except for a removable insole, to promote a barefoot and natural running sensation. The outsole is a puncture-resistant layer from a patented synthetic material, which claims to withstand five times more stress than standard soles.

The Primus Trail SG has a standard running shoe length, but available sizes are limited. The forefoot has a broad construction to promote a maximum toe splay, following the concept of barefoot running. The width profiles for both men’s and women’s versions are available in medium.

The outsole of the Vivobarefoot Primus Trail SG comprises eco-rubber, a no-sew material that is from recycled tires. This rubber equips the sole with high abrasion resistance and superior grip where it is most useful.

Introducing the Pro5 layer, a synthetic, ultra-thin material that aims to combat and resist punctures which could damage the shoe or injure the foot. The Pro5 is five times more puncture-resistant than the common outsole material.

Because it aims for barefoot-style running, the Primus Trail SG has no midsole or any other cushioning layer. Instead, it has a Poliyou® insole to provide comfort to the underfoot. Poliyou® has activated carbon that absorbs odor, keeping the foot dry and bacteria-free. This sock liner is removable and washable without deteriorating the quality.

The upper of the Primus Trail SG consists of 3M™ mesh and laminated synthetic material to promote breathability and maximum comfort.

There is a water-resistant layer that protects the shoe from getting wet. It includes quick-drain zones which effortlessly purge water to keep the foot dry and eliminate distractions during running.

A neoprene ankle collar is present, serving as a snug buffer to prevent debris from entering the shoe while also maintaining the mobility of the runner by delivering ample support.

The shoe uses a speed toggle lacing system for a quick wearing technique that guarantees no slipping, no unraveling, and no interferences while on the go.

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.