If you are looking for thermal clothing for outdoor activities you must take into account the conditions you will face. It seems logical but sometimes we overlook the obvious. A quick walk in winter, a nice trip to a rural tourism house or a car trip is not the same as a mountain climb, and the cold you will face is not even close.
The requirements are not comparable in terms of temperature, so that the quality of the materials that we find has to be higher. We cannot risk that the seams are not properly sealed and that the garment does not provide the warmth that is expected, because it could turn to be a big mistake.
But there are other aspects to consider when choosing thermal clothes to go to the mountain, and one of them is the mobility. The clothes you choose must allow freedom of movement. Materials must be durable and comfortable. We cannot end the day with a cloth that prevents the movement of the arms, for example.
Among the brands that I like for this type of clothing I’d like to recommend Haglöfs, The North Face and Helly Hansen. Similar prices and excellent qualities in all cases. Particularly the first gives extraordinary results, not only in terms of thermal insulation but also with regard to design and functionality.
Trango, Millet and Salewa also offer good products in their mountains line. Icebreaker and Arc'teryx combine quality with affordable prices, that will allow for the same budget to purchase a garment with slightly higher performance.
Finally, when choosing between natural or synthetic fibers, in this case natural fibers may not be the best idea since they retain more moisture than the other. Except in the case of Merino wool, which natural properties work well in the mountains.
Ready to go to the mountain? Wait, equip you!
The north face M flux power stretch pant
Haglöfs wigo II Q tights