Snow and ice used to keep FiveFingers wearers and other “barefoot”-style runners indoors. No longer. The Vibram Lontra, new last month for $150, is an insulated model made for temps more often dedicated to winter boots.

I’ve been putting the Lontras to the test over the past month on winter runs from GearJunkie HQ in Minneapolis, Minn.

My take? In short, the Lontra does exactly what it sets out to do — the beefed-up, multi-layer upper provides a buffer from the cold, and impressive water resistance in sloppy conditions. A light fleece liner inside the shoe adds additional warmth. And an extended neoprene cuff seals snow and moisture out at the ankle and keeps heat inside.

Even without socks, which I’ve never cared for while wearing Vibrams, the Lontra has proven comfortable down to about 20 degrees F. I should make clear that my feet are in no way immune to the cold, and I’d actually qualify my toes as pretty wimpy in cold conditions. So, I was pleasantly surprised by the level of warmth afforded by the Lontras. Many runners might not venture out at as temperature dips below freezing, but we’re confident the Lontras will be suitable for many runners at, and even below, freezing.

In an effort to test the shoes’ traction, I’ve been deliberately running on patches of ice, snow and slush. The aggressively-treaded outsole hasn’t failed me yet, as I haven’t lost my balance or taken a spill yet.

Compared to other Vibram FiveFingers models, the Lontra is a clunker at 7.6 ounces per shoe (Euro size 43). That’s at least 2 ounces more than most other VFF models. But that weight is still well below nearly every minimalist shoe out there, let alone a shoe that can handle the winter.

The Lontras are noticeably stiffer than other VFF shoes I’ve run in — specifically, in the toes. The pinky-toe “sleeve” is so stiff that I have trouble moving it at all, if I raise my foot off the ground and curl my toes. As much as I’d like to say I’m a discerning enough minimalist runner to detect a difference between the Lontras and my Bikilas during a run, I can’t. Which is a good thing. The shoes manage to keep my feet warm and dry, while staying true to their minimalist design foundations. And I get even weirder looks wearing them into the grocery store than I do during the summer.

These shoes — the winter version of the “normal” summer-weight FiveFingers — are certainly not for everyone. If you have experience running injury-free in other VFF models and live in a cold climate, give the Lontras a serious look. If you haven’t run in toe shoes before, winter’s not the time to start.

Over the past few years, I’ve logged regular mileage in my Bikilas during the warmer months in Minnesota, but am always bummed out when I’m forced to retire the shoes for the year at the first sign of winter. Thanks to the Lontra, I’ve managed to avoid my toe shoe separation anxiety this winter.

—Patrick Murphy is an assistant editor.