The Best Base Layers For Winter Trail Running

We might technically be past the winter solstice, but there are a lot of winter runs left before we can break the split shorts out again. With months of cold weather stretching out before us, it’s a good time to build a strong base. Base layers, that is.

Layering is critical to keep you comfortable on cold-weather days. While we usually warm up after a mile or two, when the temperatures really start to drop it becomes a matter of both safety and comfort to make sure your skin is covered and your core is warm. 

Base layers are next-to-skin layers that should be soft, light and moisture wicking. More than just a long-sleeve t-shirt, base layers should be tighter fitting (without being restrictive) to improve wicking. It should feel lightly compressive, not loose and baggy.

Aim for a long-sleeve layer that could fit under a jacket or shell without limiting mobility throughout the shoulders. Think about the jacket you’ll be layering it under (find our favorites here), and make sure your base layer is a quick-drying fabric made for higher-output activity. For bottoms, look for leggings or tights that offer some compression but are lightweight enough to fit under rain pants or a thicker outer layer for the coldest days. Remember, the base layers that are great for running (high output) are different than what works for skiing (lower output). For extra protection, tuck your base top into your pants or leggings, and leggings into socks.

Our editors and testers (who live in some extra-chilly climes in the Rocky Mountains) put the pedal to the metal, testing gear in temperatures as low as -10 degrees. Here are their picks for stretchy, soft and comfortable base layers for your entire body.

Brooks Notch Thermal Long Sleeve ($60)

A heavier base layer, this long sleeve has an extra-soft interior for maximum comfort, with thumb loops to make sure that pesky inch of skin between the end of your sleeve and your gloves stays covered. It’s warm enough to be your only layer on cool days while being light enough to go under a jacket (or two) for the coldest of runs. Plus, it’s odor-resistant and extra stretchy, keeping you fresh and making it ideal for hard workouts that need a big range of motion.

Rabbit Cocoon  ($125)

Combining Polartec Power Wool and Merino features, the Cocoon is a powerful winter layer for the toughest weather. Wind-resistant and sweat-wicking, this layer is light enough to go under a jacket for truly heinous days, but tough enough to stand up to the elements on it’s own for high-output activity. A built-in hood and neck gaiter ensure protection against biting winds, and thumbholes keep sleeves in place even on the most blustery runs. 

RELATED: How Cold Is Too Cold To Run?

Tracksmith Brighton Base Layer ($88)

Over 50% merino wool makes this super lightweight top extra soft. We find that some wool base layers aren’t very stretchy, but this one blends in nylon and polyester for the best of both worlds. A completely seamless design eliminates chafing, and Tracksmith’s merino is more sustainable than engineered alternatives (plus, it’s collected humanely). Unlike some wool garments, it’s not scratchy and provides a great blend of warmth and lightness. 

Tracksmith Turnover Tights ($128)

Have you ever had a piece of gear that made you feel the way the pros look on Instagram? These might be that piece when it comes to base layers. With a soft interior and sleek outside, they’re built for moving fast when the weather is cold. Tracksmith uses a unique “backstretch” waistband to eliminate that feeling of needing to yank up your tights every other mile, and breathable panels down the inside of the leg keep moisture at bay in all the places we get sweatiest. 

Oiselle Flyout Tights ($112)

Our testers agreed that these were some of the softest tights they’d ever worn. Blending super-stretchy fabric with just the right amount of compression, they’re good for everything from a weekend long run to a yoga session. Extra high-waisted, they stay right where they’re supposed to, and a long inseam made sure the ankles of our taller testers weren’t left out in the cold.

RELATED: The Importance Of Not Getting Too Cold On Winter Runs

Icebreaker BodyFitZone Merino Baselayer ($95)

This base layer is great for high-output activities in frigid weather. Merino wool is naturally antimicrobial, odor-resistant and sweat wicking. This layer fits like a second skin for effective temperature control and wicking. The zone mapping means you have extra protection against the elements where you need it, and small perforations for ventilation where you’re sweatier. If you’re doing tough workouts in winter weather, this is a great base for runners who don’t let cold weather stop them from going hard. 

Bonus: Buff DryFlx Headband ($17)

Of all the things we sometimes forget to cover in the winter, ears might be the most painful when they get frozen. Known for its classic and popular neck gaiters (we’ve all used one as a mask at the grocery store once or twice, right?) Buff filled the frozen-ear void with this headband. A snug band on the front side keeps it from sliding back, meaning you can crank the speed as much as you want and know it’s going to stay in place. It’s lightweight and doesn’t interfere with hearing, and includes reflective logos that make you extra visible in low light.