Popsugar Health & Fitness Fitness Shopping The Bestselling Amazon Workout Clothes 15 of the Cutest Bestselling Workout Clothes on Amazon, Starting at Just $5 5 August 2020 by India Yaffe View On One Page Photo 10 of 15 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 10 Under Armour Fly By 2.0 Running Shorts These lightweight Under Armour Fly By 2.0 Running Shorts ($19, originally $25) are so easy to wear. Under Armour Fly By 2.0 Running Shorts $19 from amazon.com Buy Now Previous Next Start Slideshow ShoppingFitness ShoppingProducts Under $50Workout ClothesAmazon