Multilayered clothing
Layering has caused a veritable revolution in outdoor sports. This principle allows people to be active outside in the cold or humidity while remaining dry and without shivering.
Buying
First Layer: Undergarments
Worn directly against the body and made of synthetic waterproof material (polyester or polypropylene) or other fabric (such as merino wool), the undergarment (or the base layer) removes most humidity released by the body.
Depending on the activity, it will be thin (for sports with high energy expenditure, such as cross-country skiing), medium (relatively strenuous activities) or thick (for activities that require less effort, such as downhill skiing).
In warmer weather, silk can be used instead of synthetic fibres, but cotton should be avoided at all costs: it absorbs humidity and dries very slowly, which results in losing body heat.
Second Layer: Fleece
This layer has two purposes: it insulates and it gets rid of humidity that was not absorbed and eliminated by the first layer. Here, merino wool is very effective, but synthetic fibres are the most widely used. For synthetic fibres, depending on the outside temperature, you can choose fleece 100 or fleece 200.
Fleece 100 is light and provides optimal humidity evaporation. It is worn directly on the skin as an undergarment (average temperatures) or over the undergarment (cold temperatures).
Fleece 200, which is thicker, is designed to keep the body warmer. It also eliminates humidity, but offers higher insulation. Certain high-end models have vents to promote the evacuation of humidity during intense physical activities.
In very cold temperatures, the second layer can also be an insulating garment (ideally made of synthetic fibres) or a soft shell garment (made of elastic material, which breathes while providing good insulation).
Third Layer: The Shell
It is not because the external layer is thin that it does not protect well against the cold: its main function is to break the wind and prevent it from reaching the body, and thus losing heat.
Some shells are made of windbreaking material, which simply prevents gusts of wind from cooling the body; others are fully waterproof and prevent the rain from soaking the inner layers of clothing.
However, the best shell is the one that always keeps the body warm and is breathable. Its main design feature is to fully protect against the wind and rain while eliminating body humidity. The result: Inner clothing remains dry and the body retains heat in all conditions.
Use
The advantage of a layered system is that you can add or remove a piece of clothing under the shell depending on the level of intensity of the activity. Regardless of the temperature outside, there are always ways of building your own system to protect against the cold and be comfortable under any conditions, which is impossible with an insulated garment.
To do this, you must wear the correct number of layers (generally two or three) and ideally put an additional layer (polar fleece) in your backpack to possibly add on or to replace a layer that has become soaked.
The fleece must be worn as close to the body as possible to store and eliminate humidity released through the bodys perspiration.
If the intensity level of an activity quickly increases, simply open the closures in the shell (and in the fleece if applicable) to promote the evacuation of humidity to the outside. Simply do up the closures if the activity becomes less intense.
If you know that you are going to be doing an intense activity, you can remove a layer right at the start, since the large energy expenditure will quickly warm up the body.
Maintenance
In general, wash technical clothing as soon as it needs to be.
Wash and dry clothing by closely following the manufacturers label.
Always thoroughly rinse clothing to remove any excess detergent. Avoid fabric softeners: they encourage water penetration in the tissues, and tend to remain in the clothing fibres.
When travelling, rinse any piece of clothing exposed to salt water with fresh water.
Never dry clothing near a fire (especially because of the sparks) or under the hot sun.