Sportswear is typically designed to be lightweight so as not to encumber the wearer. The best athletic wear for some forms of exercise, for example cycling, should not create drag or be too bulky.
On the other hand, sportswear should be loose enough so as not to restrict movement. Some sports have specific style requirements.
Standardized sportswear may also function as a uniform. In team sports the opposing sides are usually identified by the colors of their clothing, while individual team members can be recognized by a back number on a shirt. In some sports, specific items of clothing are worn to differentiate roles within a team. Spandex is the preferred material for form-fitting sportswear.