Functional base layer - sets 👚🩳

Functional underwear sets (often called thermal underwear) are designed to act like your “second skin.” Their main job is to keep you dry, warm, and ensure that your other layers of clothing can perform at their best.

Why choose a whole set instead of individual pieces?

Buying a set (shirt and pants) is not just about aesthetic coordination. It also has practical advantages:

Better price: Buying a set usually saves you money compared to buying the top and bottom pieces separately.
Coordinated functionality: The entire set is made of the same material, which means that your body is provided with even moisture wicking and thermal insulation across the entire surface.
Ideal layering: Sets are designed so that individual pieces build on each other and nothing presses or hinders you under other layers.

What materials are used in functional underwear sets?

The choice of material depends on your activity and how much you sweat:

Synthetic materials (Polyester, Polypropylene): Master at wicking moisture. Ideal for high-intensity activities (fast hill climbing, running) where you need sweat to disappear from your skin in record time.
Merino wool: A natural wonder that keeps you warm even when wet. Merino sets are great for long, leisurely hikes and have natural antibacterial properties – they won’t smell even after wearing them all day.
Hybrid knits: Combine the best of both worlds – the durability and quick-drying of synthetics with the warmth of wool.

How should a set of thermal underwear fit my body?

For functional underwear to work properly, it needs to fit snugly. If it hangs down, an air pocket will form between your skin and the fabric, which will cool the sweat and make you feel cold. So don't be afraid of a tight fit - modern materials are elastic enough not to restrict your movement.

Is there a difference between a bike set and a ski set?

The basic function is the same, but cycling sets often have a specific cut - an extended back on the shirt (so that the wind doesn't blow on your lower back when you bend forward) and ergonomically shaped knees on the pants. However, most of our sets are universal and will serve you well for any outdoor sport.

How should I care for functional underwear so that it lasts for years?

We recommend washing functional underwear at 30°C in special detergents for sportswear or wool. Fabric softener is the biggest enemy – it coats the fibers and completely destroys their ability to wick away sweat. Also, avoid using a dryer, which could damage the elasticity of the material.

How thick should the fabric be?

With thermal underwear, you will often come across a number in grams per square meter (g/m2):

Lightweight (up to 150 g): Ideal for summer under a jersey or for intense sports in the transition period.
Midweight (150-250 g): A versatile choice for fall and regular winter.
Heavyweight (over 250 g): For extreme cold or activities where you move little.

Check out our video "How to choose thermal bottom layers for winter"

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