Do I need to wear bra inside swimsuit?
Do I need to wear bra inside swimsuit? So, should you wear underwear underneath swimwear? In general, you should never have to wear any underwear under your swimsuit. If it is a one piece, you don't need to wear a bra or panties. If it is swim trunks, swim shorts or swim briefs, you usually shouldn't wear underwear underneath those either.
What are the rules for swimsuits?
Men: suit may not extend above the naval or below the knees. Women: suit may not cover the neck, go past the shoulder, or extend below the knee. Only FINA-approved suits may be worn in USA Swimming competitions. Swimsuits must be non-transparent and appropriate.