I only wear leggings under dresses or long tops/tunics. And this pair of leggings on perfect for that. It holds the body well and it's slimming from top to bottom.. If you want it to have the effect it's supposed to have, then buy your true size. If you are looking for a more relaxed yet slimming fit, then go one size up. It is perfect for spring and fall. I haven't used these in the summer or winter, so can't really comment on that.