You know the dri-fit type shirts people use when they work out? Yeah, the fabric that wicks sweat away and keeps you cool and dry. These bed sheets, by Sheex, are made from that same material. The idea is that the microfiber polyester/Lycra Spandex fabric blend makes your bed sheets breathable, keeps them stretchy and wicks the sweat from your body from tumbling around with your workout partner. That way you can focus on performance rather than getting sweaty and stuffy.