Modern base layers have come a long way from the waffle-knit long johns that were wetted out by lunchtime after a few freeze-thaw cycles. From natural temperature-regulating fabrics like Merino wool to synthetic options engineered to wick moisture, today’s base layers are marvels of technology. Our test crew put 50 items through their paces last winter in locations across North America. Testers skied at resorts and in the backcountry, went backpacking and camping, and ran on both snow-packed trails and city paths to bring you this list of the top performers in the category.
At a Glance
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Editor’s Choice
Helly Hansen LIFA Merino Midweight Graphic Crew and Pant
$110 at REI (Top) $110 at REI (Bottom)
Sizes: XS-XL
Key materials: Merino wool, polypropylene
Comfort rating: 9/10
Breathability rating: 10/10
Warmth rating: 8/10
Pros and Cons
⊕ Two-layer construction ideal for wool-sensitive people
⊕ Excellent moisture management
⊕ Flat…
