Swimming is a sport that possesses particular challenges for manufacturers of knitted fabrics. Swimwear, caps and swimsuits made of fabrics are exposed to considerable mechanical stress. They are exposed to direct contact with water, which is often chlorinated or ozonated, risking loss of mechanical properties as a result of chemical reactions. After swimming, clothing is wet for a long period of time and there is a risk of growth in microorganisms. Sports costumes are also used in a wide range of temperatures. Beyond being used in the swimming pool, they are often taken to the sauna and exposed to the sun. Variable temperature and ultraviolet light can change the structure of the fabric if it is not properly prepared for such a hostile environment. Growing concerns for ecology impose the need for low-energy manufacturing and recycling processes. Effectively, production of good fabric becomes a challenge. First of all it is necessary to use the highest quality materials and meticulous observance of quality control at every stage of production.