“How can I choose a modest swimming suit?” New Era, March 2011, 34
The Church encourages modesty in dress for all occasions, including swimming. The dilemma comes when people want pictures or measurements or definitions of exactly what is OK to wear. Since fashions change from place to place and time to time, this is not possible.
For example, several years ago Church guidelines said not to wear two-piece swimsuits. At that time, “two-piece swimsuits” meant bikinis, which are very revealing. Now fashion has changed, and some two-piece swimsuits are actually among the most modest swimsuits you can buy. They are better fitting and have longer tops that cover the torso. The bottoms come in more modest styles too. So the guideline not to wear a two-piece swimsuit is not as helpful as it once was, but the goal to dress modestly remains.
In sports, recreation, and all aspects of our lives, we need to practice the principle of modesty.
“Modesty is a gospel principle that applies to people of all cultures and ages. In fact, modesty is fundamental to being worthy of the Spirit. …
“… When we recognize our bodies as the gifts they are and when we understand the missions they help us fulfill, we protect and honor them by how we act and dress.
“In everyday living, immodest clothing such as short shorts, miniskirts, tight clothing, shirts that do not cover the stomach, and other revealing attire are not appropriate” (Robert D. Hales, “Modesty: Reverence for the Lord,” Ensign, Aug. 2008, 34–35).
Concerning modesty, it is best when we no longer ask, “How far can I go?” but rather, “How well can I follow gospel standards?”