The term "American sportswear" is being taken quite literally this week with many designers churning out collections that are, well, sporty. The clothes not only channel the sporty lifestyle, but the gear as well, which is why mesh is having a moment. Alexander Wang's first five exits were completely covered in it. Meanwhile, the fabric hasn't been limited to just clothing. Those sleek ponytails at Donna Karan? Wrapped in mesh, of course.