Moisture Wicking & Breathability: The Most Important Properties of Bike Underwear
Good bike underwear is made of functional materials. Materials are able to absorb a lot of moisture and release it quickly. This is the basis for the onion layering system and is commonly referred to as a "base layer". Common materials used for this purpose include polyamide (nylon), polyester, polypropylene and the natural material Merino wool. Clever material blends are also often used. Manufacturers of bike undergarments include established outdoor brands such as Patagonia, GORE Wear and VAUDE, as well as specialists for cycling underwear, e.g. ASSOS. E.g. ASSOS, Endura, Craft, GripGrab or 7Mesh. Cotton is not optimal because it absorbs moisture but dries extremely slowly. This creates a vapour barrier that prevents any further breathability and causes you to stew in your own juices. In addition, moist skin chafes much more easily.
Functional underwear, on the other hand, stays dry even during exertion, which is more comfortable because you don't cool down or overheat. This ensures you remain comfortable at all times. You benefit from this not only during sports, but also on the way to work or university, because you won't arrive soaking wet. One thing cycling underwear cannot and should not do, however, is prevent sweat. Perspiration is an important bodily function to regulate your temperature. You don't want to pant like a dog, do you?