Layering of clothes11.05.2021
Everyone has certainly heard of layering outdoor clothing. Here we would like to summarize information and recommendations on how to dress effectively during active sports.
Layering of clothing
Thermodynamics and something more: you know that: ...two systems with different temperatures will act on each other (conduction, radiation and flow) until their temperatures equalize... Insulating materials do not warm you up; they prevent the flowing of air (the insulating medium), which they retain in their structure. The coefficient of thermal conductivity of air is more than 40-times lower than the coefficient of water. Therefore, minimizing internal humidity plays a significant role in achieving optimal thermoregulation.
Performance intensity: the more intense your physical performance, the more heat your body produces. For the body to function properly, it needs the most ideal thermoregulation possible. Internal moisture can cool the body quickly, and the body cannot compensate for such a loss. The ideal materials should be elastic, breathable, adequately insulating or divided into insulating zones in terms of body mapping.
Overheated organism: the aim of the layering strategy is to prevent the body from overheating (>39°C) – excessive sweating can reduce performance, and damp clothing can freeze or cause hypothermia (<32°C) after exposure to the wind. You can avoid overheating by putting aside one layer or using the ventilation openings on the clothes.
Hypothermia: hypothermia most often occurs in the mountains for several reasons. The clothing insulates but is unable to rapidly remove the accumulated heat; it absorbs moisture, which together with the wind quickly lowers the temperature. Without the top waterproof layer you are exposed to the risk of getting wet with the same consequence. Insufficient, but also poor quality insulation is another common reason for hypothermia with increasing elevation.
The onion strategy is based on functional layers. The bonus is a combination of various settings, but the possibility of quick exchange, replacement or reduction of any of them is essential.
The material can be a synthetic like (Polartec® Power Dry™; Polartec® Power Grid™), or a natural fabric like merino wool. Although wool does not wick away sweat as efficiently as artificial materials, it does warm when wet. Furthermore, it has antibacterial effects and thus neutralizes odours.
Function: the insulation of body heat and the transport of excess heat in the form of vapour
This layer includes thermal insulation, sweatshirts, sweaters or vests.
Function: protection against unfavourable external influences
The outer layer should be waterproof, wind resistant, adequately flexible as well as breathable.The surface of the material is often treated with a hydrophobic layer that prevents the surface from getting soaking wet. Waterproofness limits breathability and vice versa. Experience shows that the laboratory values of even the most breathable materials are not sufficient for ventilation during intensive physical activity; therefore, the clothing is supplemented with ventilation openings.
The water column shows the overall measure of water resistance under the assumption that the construction of the garment has all the seams taped. The necessary protection is provided in particular by laminated materials with a porous membrane (hardshell). The offer is supplemented by laminated softshell materials, which, aside from being waterproof, also offer optimal mobility due to their flexibility. Densely woven materials (Pertex®) with a surprising ratio of weight, waterproofness and breathability are available. The waterproof, non-porous membrane with excellent elasticity but weaker breathability – Dermizax™ – stands alone.
This parameter stands in direct contrast to waterproofness. But to solve this dilemma, it is enough to realize that external humidity in the form of a molecule of water in the liquid state is several times greater than a molecule of vapour. The pores of the membrane are too small for external moisture to enter but they do allow accumulated vapour to escape. We express breathability as the weight of the vapour released from the area of a square metre per day (g / m² / 24 hours).
We present the advantages of individual types of jackets in a clear list.
+ Membrane guarantees waterproofness
+ Taped seams
+ Hood is usually part of the jacket
– Hadrshell material is less breathable, thus it is less suitable for active sports
– Minimum insulation function
– More expensive variant
+ The jacket is breathable,
+ Softshell jackets are insulated on the back with a fine layer of fleece,
+ The material is pliable and flexible
+ Cheaper variant
– The material is partially waterproof, but in heavy rain it lets water in
– Often an absence of taped seams
Test and combine, a different combination is appropriate for each activity and temperature condition. Remember, there is no bad weather, only ...