Vivobarefoot Primus Trail III All Weather FG review

We think that the Vivobarefoot Primus Trail III All Weather FG is ideal for:

• Barefoot shoe fans who want a water-resistant option for trail running and hiking in wet and cold weather.
• Minimalists who value high-quality materials, excellent grip, and a highly-grounded feel for outdoor adventures.
• Runners with wide feet looking for a comfortable barefoot shoe for walks, hikes, and occasional runs.

The Vivobarefoot Primus Trail III All Weather FG runs extremely close to the ground, and that won't be everyone's cup of tea. If you prefer more protection and clearance underfoot, the Altra Lone Peak 9 is a better option.

We also think runners with narrow feet may prefer a shoe with a less generous forefoot. If that's you, the Xero Shoes Mesa Summit keeps the minimalist, low-stack design while using a more traditional toebox.

If you're going for a barefoot shoe, you should expect a low score in our shock absorption test. Otherwise, there must be some foam involved, and well... that's not barefoot.

Luckily for any Vivobarefoot fan, the Primus Trail III All Weather FG is a true barefoot shoe, delivering an ultra-low shock absorption reading of 29 SA in the heel and 31 SA in the forefoot.

The lack of foam in the midsole means there's not much energy coming back to your body. With just 42.0% in the heel and 43.5% in the forefoot, this Vivobarefoot shoe leaves the energy storage and propulsion to your muscles and tendons with every stride. And again, that's what you want in a minimalist or barefoot shoe!

You were probably expecting a very low stack height, and we certainly felt like we were running and hiking very close to the ground, as with very few shoes we've tested in recent years.

We measured the heel stack height in our lab and found just 11.3 mm of separation between our feet and the ground.

We moved our digital callipers toward the forefoot and found exactly the same result: 11.3 mm.

That looks promising for the drop section...

The Vivobarefoot Primus Trail III All Weather FG, like all shoes from the brand, is marketed as a zero-drop shoe. And we have to give Vivo credit because this is one of the few shoes that truly nails it, delivering a perfectly flat 0.0 mm offset.

There's basically no midsole here. The shoe has a paper-thin insole sitting directly above a thick rubber outsole, so we measured the rubber because it's effectively the only layer providing any cushioning.

We pressed our Asker C digital durometer against it and got a reading of 78.9 AC. Therefore, we once again confirmed that there's no soft foam in the shoe, just an ultra-firm rubber outsole.

As expected from a barefoot shoe, the Vivobarefoot Primus Trail III All Weather FG has no rocker whatsoever, delivering a completely natural ride.

Vivobarefoot is a brand known for its anatomical fit, although it's also considered one of the narrower brands within the barefoot shoe community that offers this foot-shaped forefoot. Let's see what happens here!

In our first fit measurement, the Vivobarefoot Primus Trail III All Weather FG confirmed that it's more than ready to accommodate wide feet.

In the toebox, we measured 78.5 mm. Therefore, that reputation on Reddit that Vivobarefoot isn't quite as wide as some other barefoot brands still holds true, as the toebox is slightly more tapered than those from brands that really embrace a super-wide design.

At the same time, for runners coming from conventional shoes or those with narrow feet, this Vivobarefoot will provide a perfect fit.

The toebox works particularly well for runners with high-volume feet or anyone who enjoys having plenty of room to wiggle their toes.

We found 28.9 mm of height, which is more than enough for everyday use and even day-long hikes.

This version of the Vivobarefoot Primus Trail III comes tuned for firm ground, and we were really curious to see how it would perform in our SATRA TM144 traction test.

Well, it turned out to be an impressive performance. With a coefficient of friction of 0.84, this barefoot shoe showed that it's ready to handle both dry and wet conditions as long as the terrain doesn't get too technical.

And we want to emphasise the lack of technical terrain because this shoe is specifically built for the opposite.

With 2.9 mm lugs arranged in a very dense pattern, it works wonders on packed surfaces like dirt roads.

Just don't ask it to tackle deep mud or thick grass because it's simply not built for that.

We also loved how Vivobarefoot went wild with the design, creating a clear visual path that follows the natural shift in pressure from heel to toe and giving the outsole a seriously futuristic look.

As expected from any minimalist shoe, the Primus Trail III All Weather FG delivers excellent flexibility. That said, the rugged outsole adds some stiffness, but that's no surprise, and 5.5N is still an impressively low reading.

One thing that's becoming a pattern in our lab is finding that minimalist and barefoot shoes are heavier than they look for their size. The Vivobarefoot Primus Trail III All Weather FG joins that group with a weight of 10.5 oz (298g).

Like cushioning, stability is largely up to you.

If you're a neutral runner with no need for support, you'll be trouble-free with the Primus, as running this close to the ground creates virtually no inherent instability. However, if you tend to collapse into your arches, the shoe won't provide any support to compensate.

Any Vivobarefoot shoe should be highly-twistable, and the Primus Trail III All Weather FG certainly fits the bill. We confirmed this in our lab, where it took just 5.8 Nm of force to complete the test.

The heel counter has some structure, which we believe is a smart choice for a trail shoe designed to handle twisty, undulating terrain.

When running in the Vivobarefoot Primus Trail III All Weather FG, we constantly felt like we had a solid base under our feet.

That's because Vivo added some width through the shoe's thick outsole rubber, creating a broad, confidence-inspiring platform that tops out at 113.0 mm.

Where this shoe differs from regular trail shoes is in the heel area. Here, we found just 77.7 mm, which, when you look at the natural shape of the foot, makes perfect sense and stays true to its foot-shaped design.

There are no red flags when it comes to toebox durability, as the Vivobarefoot Primus Trail III All Weather FG scored a solid 3 out of 5 in its first challenge against our Dremel.

Unfortunately, we can't say the same about the heel padding.

Here, we had to give it a 1/5, the lowest possible score in our methodology. It's comfortable, but there's a trade-off for that comfort.

Back to a more positive note, and this time a truly impressive one. With just 0.5 mm of wear, the Firm Ground outsole delivered an excellent durability result that, combined with its top-tier traction, left us seriously impressed.

As we found earlier, Vivobarefoot ditched any midsole foam and essentially made the outsole thicker for added protection. We can see the reasoning behind this decision, as some protection is always welcome on the trails.

Here, we confirmed it with a 3.7 mm reading, adding a bit of extra trail-ready protection without compromising the shoe's minimalist design.

We were very careful when measuring the insole thickness because it's razor-thin! At just 1.7 mm, it's perfectly in line with the minimalist design of this shoe.

The Ortholite insole can be removed easily. However, fitting a third-party option won't be easy, as you'll probably need to find one that follows the foot-shaped design of this Vivo.

We love it when brands use their logos to add reflectivity, so kudos to Vivo for doing exactly that here!

Vivobarefoot has ditched regular laces here and gone all in with a quick-lacing system that will surely divide opinions. Obviously, it speeds up the process a lot, but the aesthetics may not please everyone, and the cord might be a bit too long for most feet.

To be honest... you know how it goes: PR photos can look awesome, but in real life, things don't always look quite as good.

The tongue is very thin, with just 1.7 mm of padding and basically no foam to cushion the instep. However, since the quick-lacing system doesn't create much pressure, we're perfectly fine with this.

One thing we would change is attaching the tongue to the upper, both to prevent it from potentially sliding sideways and, more importantly, to fully block debris from getting inside.

The heel could've featured a finger-loop heel tab, which always adds a trail-ready vibe to a shoe, but this model comes without one. Nevertheless, the heel is nicely finished, and we were impressed by the build quality.

Vivobarefoot is well known as a premium brand in the minimalist world, and the Primus Trail III All Weather FG proves it. It's not the best pick if you're looking for a budget-friendly price or excellent value, but that's the trade-off. If you want Vivo, you've gotta pay for it!