Working out in summer is hard enough (can't we just sit by the pool with a cool drink instead??) without the added challenge of finding something to breathable enough to wear. Your yoga pants and t-shirts just won't work--they aren't breezy enough for outdoor, mid-summer exercise. Instead opt for one of these open-back exercise tops--they are supremely comfortable and cool. Shop now-->[Photo: Without Walls Dri-Release Layer Tank Top]