Baselayer, thermal underwear, long underwear – these terms all mean the same thing, but they’re not always built the same. Often the most common types of baselayer are made of wool or synthetic fabrics. And both have their advantages – but what's the best for you and your activities? Here’s the scoop on everything you need to know about thermal underwear, so you can make an educated decision on the right type of baselayer for you.
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Wool insulates heat: Wool baselayer is unique in that it keeps you warm, even when the garment gets damp! Therefore, it may be smart to choose wool for longer mountain adventures where thermal insulation is important.
There are many reasons why we love wool. It regulates your body temperature to a comfortable level based on the ¬conditions: It cools you down on hot days, and insulates warmth on cold days. Wool also has the unique ability to keep you warm, even when it gets damp! If you are doing activities that make you sweat a lot, or there is a risk of rain; wool will absorb moisture and still manage to isolate heat. In fact, wool can hold up to 30% of its own weight in moisture and still feel dry. Wool baselayer is also perfect for camping trips because it is self-cleaning. All you have to do is hang the wool garments up for airing, and they feel fresh again for the next day. The unique breathability of the wool also makes it very comfortable to be active in, because it prevents you from becoming clammy. Read more about the benefits of wool here.
Conclusion: If you are going on longer trips on the mountain with unstable weather, you should choose wool baselayer.
Wondering how to wash the wool properly? Check out our washing guide here.
Great properties: Synthetic baselayer has the ability to transport sweat away from the skin, it dries quickly, is durable and feels comfortable to workout in.
Synthetic baselayer is usually made of artificial fibers such as polyester, often added elastane to ensure full freedom of movement. It provides a material that is excellent for high-intensity exercise because it wicks away sweat from the skin, dries quickly, is durable and feels comfortable to workout in.
Conclusion: If you're going to train hard, get sweaty (and have access to a shower afterwards …), synthetic baselayer is your best choice.
The best of both worlds: By mixing technical fibers from the synthetic baselayer with natural wool fibers, we get the best of both worlds.
We have developed several varieties of baselayer that combine wool with synthetic fabrics. The combination of quick-drying and moisture-wicking properties of synthetic fibers, and the heat-insulating properties of the wool, gives you the best of both worlds. A wool blend is therefore perfect for high-intensity activities in the cold.
Kari Traa have also made 100 % natural wool blend baselayers by adding cellulose fibers – which are actually developed from residual waste from trees! By mixing wool with these natural wood fibers, the wool garment become more durable. Like technical baselayer, cellulose fibers quickly transport moisture away from the body and helps you stay dry. They are also incredibly soft to touch, and feel twice as soft as cotton! Read more about the sustainable super fiber here.
Conclusion: If you’re up for high intensity activities in cold weather, a wool blend may be your perfect choice.