Our colleagues at Snow and Rock have prepared some notes about the layer system of clothing. I'm going to put these up as a number of separate posts over the next few days, so look out for the next installments. Here's the introduction:

Clothes are there to do a job, keep us warm dry and not naked. The way we keep ourselves warm in the various climates of the world is by applying layers. This system is the same for whatever sport you are playing or doing from rugby on a bitter winter day to the skiing in the Alps through to climbing Everest, the principal is the same keep the body warm and protected.

The Layering system is built up of three different sections that each does a specific job it is possible to wear several garments of any of the layers but for simplicity this is how they are broken down.
Base Layer – Keeps you warm and dry transporting the sweat or wick it way from the skin.
Mid Layer – This is the thermal layer there to keep you warm
Outer Layer – This is the outer protection or armor from the elements wind proof and waterproof.

The bodies’ core temperature is 37.5º C; this is the optimal temperature where the body is most efficient. The brain regulates this, as the temperature drops it will bring the blood from the extremities into the core of the body which contains the vital organs. If the temperature would drop by 3hi there
ºC in the torso you would be suffering from severe hypothermia.

The basis for the layering system comes from the animal world. Look at a gooses feathers the small down feathers take moisture from the skin the next set of feathers provide the warmth and the outer feathers are coated so that water does not penetrate through.

Coming soon, Episode 2 ... The Base Layer