This lightweight but high-performing base layer needs to be part of our essential kit for moving comfortably in cold-weather conditions
Light, comfortable and warm
Precise fit with superior freedom of movement
Ultra breathable with fast-drying moisture management
Thermo-regulation for high intensity activities in cold conditions
No thumb hoops
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Smartwool Intraknit Merino 200 Crew: first impressions
On the rack, this light, minimalist base layer boasts a classic long-sleeve crew design to keep you warm in cold weather conditions. This is a medium weight, slim-fitting base layer combining the moisture-wicking capability of merino wool with the fast-drying time and durability of polyester.
This top provides thermoregulating, sweat management and odor-resistant technology so it’s what you need when you plan to get hot and sweaty in cold weather. The design uses 3D knitting technology to result in a snug, precise fit without adding annoying, scratchy seams while mesh panels are knit into the garment where you need them to enhance breathability. This allows you to move easily and break a sweat in colder weather without sacrificing comfort.
This high quality garment comes with a high price tag but should keep you warm and comfortable through a lot of winters and makes a worthy addition to your outdoor kit in colder months.
• RRP: $120 / £119
• Sizes available: Men’s S - XL, Women’s XS - XL
• Materials: Merino (52%), polyester (45%), elastane (2%), polyamide (1%)
• Colors: Black/white, Blue spruce, Pomegranate, Tibetan red, Military olive, Deep navy, Forged iron
• Best use: hiking, mountaineering, camping, winter sports, winter trail running
Smartwool Intraknit Merino 200 Crew: on the trails
This is not my first rodeo with a Smartwool base layer but they last so long and so well that it’s over a decade since I’ve needed a new one, so I was excited to test this one out and it didn’t disappoint.
I really like my base layers to be slim fitting without feeling restrictive and Smartwool have got this down to a fine art. This one fits like a glove yet I can easily move in all the ways I want to for winter sports from cold-weather trail running to skiing uphill.
I worked up a good sweat in this top and it was definitely super breathable and I was dry again soon after which is just what I’m looking for in a base layer. Also, because it’s made of Merino wool, it didn’t get stinky afterwards. I don’t like to wash my base layers after every use to make them last longer so this is really important to me.
The design is super minimalist. All of my other Smartwool base layers feature a 3/4 zip which I do typically unzip when I’m uphilling on skis and snowshoes, but I found I didn’t miss it with this top, owing to its breathability. It doesn’t feature thumb loops which is not a big deal for me but I know it can be a dealbreaker for some.
Finally, it looks good on and I’d be happy to wear it around town as well as on the hill, which is a bonus.
It certainly runs pricier than a lot of other base layers, but as I already attested, if you take care of these (meaning, cold gentle wash and don’t tumble dry them) they’ll last you over a decade even if you give them a beating every winter like I do. In the long run, you’ll probably save money buying one of these instead of one at half the price which needs replacing every couple of years.
As I said, it’s not my first Smartwool base layer and it’s unlikely to be my last.
Here’s how they performed:
True to size. The only reason to size up would be if you like a looser fit but remember, this is very stretchable and I’m convinced you want your base layers to be skin tight.
Slim fitting, long sleeved crew. The company uses 3D knitting technology to produce what they call a more precise fit and while I don’t fully understand what that is, it works and looks good.
Very comfortable in terms of movement and barely any of that scratchy wool feel at all.
This base layer does the job it’s supposed to do: keeps you warm in cold weather and cools you off when you start sweating by wicking the moisture away and drying quickly. It’s a medium weight so good for very cold temperatures, but might be too warm under some conditions.
No ventilation chest zip but with this breathable fabric, you won’t need one. If you get sweaty, you’ll dry out quickly in this top and won’t feel too hot unless you’re wearing it in warm weather.
Though I haven’t had this for a decade like my other Smartwool base layers, based on the quality I expect it to last at least as long.
Here’s where we tested the Smartwool Intraknit Merino 200 Crew:
Ben Arthur, otherwise known as The Cobbler, is a distinctive peak at the head of Loch Lomond. The true summit requires some technical scrambling that many choose to miss.
Julia Clarke is a staff writer for Advnture.com and the author of the book Restorative Yoga for Beginners. She loves to explore mountains on foot, bike, skis and belay and then recover on the the yoga mat. Julia graduated with a degree in journalism in 2004 and spent eight years working as a radio presenter in Kansas City, Vermont, Boston and New York City before discovering the joys of the Rocky Mountains. She then detoured west to Colorado and enjoyed 11 years teaching yoga in Vail before returning to her hometown of Glasgow, Scotland in 2020 to focus on family and writing.