I have always been under the impression that cotton is the enemy of a hiker - it absorbs moisture and just becomes a horrible wet casing around you, transferring away all the heat.
I was therefore quite surprised to find that a new sleeping bag I had purchased actually has cotton lining. Is this not counterproductive? Or does it not matter so much, assuming I do not get into the sleeping bag all sweaty and wet? Should I take any special precautions with this bag?