Anyone who lives an active life, does sports and spends a lot of time outdoors, knows how important proper layering of clothing is.
Functional underwear is a solid foundation, on which your comfort is based during every sporting activity. It performs several functions and all make you pleasantly warm and dry.
Functional underwear allows for the sweat to evaporate from the skin in summer, or it leads the sweat to other layers of clothing and prevents a loss of heat in winter.
You need thinner functional underwear in summer and warmer functional underwear in winter, so that it can properly fulfil its function - to take care of your comfort during active movement in any weather.