For base layers, the two fibres most used in winter sports are polypropylene and merino wool. There's no single best fibre: there's the right one for how you move.
Polypropylene: dry when you sweat
Polypropylene is the lightest textile fibre and one of those that absorb the least water. In DryHeat Lab tests its weight increases by 0.13% after absorbing liquid, versus 0.72% for polyester, 2.11% for nylon and 7.03% for cotton. Sweat doesn't stay in the fibre: it moves outwards and your skin stays dry.
Choose polypropylene if you move hard and sweat a lot: ski touring, winter running, fast climbs, cycling. It is the basis of DH Extreme Power.
Merino: warmth even when still
Merino wool is a natural fibre that keeps you warm even at low activity levels and handles odours well. It absorbs more moisture than polypropylene, so on its own it dries more slowly.
Choose merino if it's very cold, you don't move much or you take long breaks: chairlifts, snowshoeing, outdoor work.
Polypropylene and merino together
In the DH Drywool top the two fibres work together: polypropylene next to the skin carries sweat away, merino holds in the warmth. It's the choice for activities with effort and stops on the coldest days. Composition: 60% polypropylene, 28% merino wool, 8% polyamide, 4% elastane.
In short
- Fast pace and lots of sweat: polypropylene.
- Intense cold and little movement: polypropylene and merino.
- Alternating effort and stops: polypropylene and merino next to the skin, with a mid layer on top.
For a choice tailored to you, use Find your layer.