There are times when you just can’t avoid being uncomfortable, but when you’re not on bivvying on a ledge a decent sleeping mat is essential kit. The best sleeping mats are warm, comfortable, lightweight, pack down small, and are reliable. They are every bit as important as a good sleeping bag.
Feeling strong and ready for a big day ahead or recovering after a long route requires good sleep, and a sleeping mat is essential for that. Suddenly, even the most remote and inaccessible camp can be made to feel comfortable.
The ground conducts heat up to 60 times faster than air, and if sleeping on ice that it increases to 90 times. That means a huge amount of heat can be lost to the ground, and a sleeping mat helps negate that.
A test worth trying is to use a warm sleeping mat instead of a regular one and see how much lighter a sleeping bag you can get away with. Often the resultant combination of mat and bag is lighter, and more comfortable too.