USE COUNCIL
Dressing too warmly after heavy physical exertion can make you feel cold. Perspiration can't evacuate properly, so it remains in permanent contact with the skin. This is why it's a good idea to wear an under-jacket, which you can remove in milder weather. It's also important to open the vents before you get too hot, and close them again before you get cold when the intensity of the effort decreases, as on the ski lifts.
What should I wear under my ski pants?
To stay warm and dry, apply the 3-layer rule: 1 breathable ski undergarment, 1 under-jacket for warmth and 1 ski jacket for protection from the elements.
The first layer
It keeps you dry by transferring perspiration from the skin to the other layers.
The second layer
For warmth, you need a second layer to insulate you from the cold. This is the role of sweaters, fleeces and down jackets.
The third layer:
Protection from the elements (snow, rain and wind) by keeping them out (while still allowing perspiration to escape, so you don't get "wet from the inside"). So, ideally, it's waterproof AND breathable. The third layer can also help insulate lined jackets or pants, thus complementing the action of the second layer.
