The Patagonia Women's Capilene Thermal Weight Bottoms will do better than your average long-johns. First off, The Polartec® panels do their job to lock in heat, but also let the breeze through while you are on the move. The seams all lay flat, the finish is soft, and everything layers easily. The fabric has enough spandex to keep your movement free but not too much to make you over-heat. They feel like skinny yoga pants that also keep you warm. Layer them in the winter, take them into the back country, or wear them under your ski gear.