The Rho bottoms from Arc’teryx are heavyweight thermal underwear for days when the temperature dramatically drops. They’re designed to perform on the slopes, but they’ll serve you well on a windy and cold day in the city, too.
The Polartec Power Stretch fabric is made with a nylon face and a brushed, soft polyester inside. These thermals are very durable and wick moisture quickly, keeping you warm and dry even during high-output activity.
The trim fit makes for easy layering under ski pants or jeans, and the laminated zip pocket at the thigh keeps small essentials like keys secure. This pair runs small for some so consider sizing up, though I took my normal size and found them comfortable.
I use the Rho bottoms mostly for lounging around because of the cozy brushed interior. It’s super soft against the skin and feels like a pair of fleece sweatpants. The pocket means they can double as running tights, but since they’re so warm, I only use them if it’s really cold.
The waistband isn’t as wide as others but it still stays in place and doesn’t chafe or get uncomfortable. They’re too hot for high-output activities on mild days, but the brand also makes a lightweight version if you want more versatility.
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