One-piece swimsuits are generally not recommended to wear underwear. One-piece swimsuits are mostly made of nylon, polyester fiber and other materials. The fabric is thick and elastic, and generally does not sag or swell when it meets water. In addition, although the one-piece swimsuit is close to the body, if you put on underwear, it will strangle your skin and cause physical discomfort. One-piece swimsuit should wear underwear? One-piece swimsuits usually use high-elastic fabrics, and some loose underwear may not fit the body as well as swimsuits. If you wear underwear in a one-piece swimsuit, it may show a more obvious underwear shape, which is not very beautiful when swimming. At the same time, underwear is mostly cotton, which is easy to absorb water, but it is easy to absorb bacteria after entering the water. One-piece swimsuits generally have chest pads and pads, which can play a certain role in fixing, and generally do not need to wear extra underwear when swimming. When buying a swimsuit, you'd better choose a swimsuit that suits your body shape, not too tight or too loose. If you are worried about running out, it is best not to choose a split swimsuit and choose a one-piece swimsuit with better wrapping.