The document discusses the technological development of sports textiles and provides an overview of synthetic fibers like nylon, spandex, and acrylic that are essential materials for athleisure due to their performance properties. These man-made fibers provide attributes like stretchability, moisture-wicking, easy care, and durability that make them suitable for active and comfortable clothing. While synthetic fibers have environmental impacts, their benefits have led to their increased use in athleisure and other active and comfortable clothing applications.