Hiking clothes share a lot of common purposes with normal everyday clothing. While clothing in general is supposed to keep you warm, dry, and protected, the purpose of hiking clothes is about the same, but with added protection against weather conditions, terrain conditions, and other situations you expect to encounter on your hike.
However, this does not mean that you should choose your hiking clothes without even the semblance of care. Your attitude should not be, "as long as I carry lots of extra clothes with me, I should be okay." That's because the general rule about traveling light still applies.
Just like hiking boots, hiking tents, and all other gear, weight and bulk are serious considerations when it comes to hiking clothes.
Below are some of the basic purposes of having appropriate hiking clothes to wear while on the trail:
People often refer to hiking clothes like sweaters and jackets as "warm clothing" when actually, the purpose of hiking clothes like these is not to increase your body temperature. What they do instead is to help you keep and maintain a thermal equilibrium.
What does thermal equilibrium mean? The term simply means that your body is generating as much heat as you are loosing it. That way, your body does not have to produce extra heat or lose it through sweating. Producing extra heat or sweat can be very taxing on your body, draining down your total energy. By wearing hiking clothes that help maintain your thermal equilibrium, you thus save your body's energy to last you for the entire trek.
One obvious function of hiking clothes is to keep you dry. If your skin is dry, your body is able to preserve more of its heat. Not only that, dry skin increases general comfort. Face it, no one wants to feel all sweaty all the time.
First, protection from outside moisture. Your hiking clothes should be able to protect you from rain, snow, and other possible sources of water. And second, protection from body moisture. Your hiking clothes should move body moisture (sweat) away from your body. The process of protecting against outside moisture while keeping body moisture away from your skin is a difficult combination that requires your hiking clothes to work in a waterproof but breathable way. That's why choosing the right set of hiking clothes is very important.
The third important aspect of your hiking clothes is its ability to provide you with protection from environmental factors other than moisture through padding. While the human skin is an absolute marvel, it is not very strong. It can get easily cut by anything that's sharp or moving in high velocity. It could get bruised, dried, and break.
The outdoors possesses a lot more danger to our precious skin than our everyday city surroundings. Thus, a lot of padding and reinforced materials through the wearing of hiking clothes are used to protect you from the possible damage your skin might undergo because of rough terrain or chaffing of equipment.