Short Cut (top)
Double your exercise pleasure with a copycat underlayer: Choosing a panty that mirrors the shape of your clothes is one of Nethero's key invisibility strategies. Folded edges lie flat; copper-bonded fibers in the fabric work as antimicrobial agents. Cass and Co. WearRepair Shaper Short, $68.

High Line (center)
Give thongs a chance (Nethero's rules: Buy a good one—comfort requires more fabric, higher cost—and allow two or three wearings to adjust to the new feeling). This high-tech fabric wicks away moisture from the body, so you won't get soggy while working up a sweat. Nite Sweatz, $17.

Brief Encounter (bottom)
Boy shorts are making a comeback, Nethero says: Full butt coverage prevents unattractive ride-up in back (reason enough for their popularity); unobtrusive edging keeps them looking smooth. At this price, you can buy a bunch to stash in your gym bag. Jockey No Panty Line Promise Modern Brief, $9.