Spandex, also called elastane or lycra, is a synthetic fiber highly valued for its incredible elasticity. Since the 1950s, spandex has been used to replace rubber in several garments, such as tops, underpants, swimwear, shorts, bras, and leggings. The material is perhaps most useful in workout undergarments and in the best women’s underwear for sweating, spandex is mixed with cotton, nylon or polyester, to offer several benefits including the following;

i.) Optimal sweat absorption– when used alone, some materials like nylon and polyester don’t absorb sweat and you have put up with the discomfort of being watery down there, which dampens your psyche to work out. However, materials like spandex and cotton do absorb as much sweat as possible, thus allowing you to continue working out while feeling dry.

ii.) Breathability and sweat-wicking– spandex is the most expandable synthetic material and thus the absorbed sweat evaporates through the expanding pores. Unlike cotton which remains wet and soggy once it absorbs sweat, spandex wicks away the sweat so that the workout panty remains almost dry. This is an important feature because the accumulated sweat in cotton becomes a breeding ground for yeast and other bacteria that can infect you with diseases.

iii.) Softness and comfort– once you sweat, synthetic materials like nylon and polyester start sticking to your skin and thus you have to keep on sloughing it off. The creases of nylon and some other materials are also don’t have a pleasant feel to the skin. In contrast, spandex is soft and keeps you feeling comfortable throughout the workout session.

iv.) Hypoallergenic- the creases and rubbing of nylon and other synthetic materials will irritate your skin and can even cause you allergic reactions. However, spandex based material remains soft and dry and it less likely to irritate you.

v.) Odorless– if your underpants are made of polyester, nylon or even cotton, once you have tanks of sweat down there, the growing bacteria and yeast make you unpleasantly smelly. The sweat wicking and expandable spandex remains dry and aerated thus free from odor-producing bacteria. 

vi.) Stain free and easy to clean– the sweat-absorbing cotton stains and turns yellowish with time, a factor that also contributes to faster aging of the garment. By releasing the absorbed sweat to the environment, the elastic spandex doesn’t get stained and it’s also a breeze to wash.

vii.) Shape retention– unlike pure cotton, spandex’s elasticity ensures that whatever the type of women’s workout underwear, it can stretch or shrink and still get back into original shape once you wash and dry it.