Women's swimsuits have come a long, long way over the past 100 years. While women in the early 20th century were expected to keep the majority of their bodies covered while swimming, modern swimsuits expose a great deal more than they conceal. When it comes to women's swimsuits today, there are a lot of choices. Even though most women's suits can be categorized as either one-piece or two-piece, both categories have a number of subdivisions. French cut one-pieces, string bikinis, thongs-all are possible options for women heading to the beach or the pool. However, when considering those women's swimsuits used for competitive purposes, the choices become a bit more limited. While most swimsuits are designed almost solely for appearance, athletic swimsuits are designed to improve the athlete's performance in the water.

Racing swimsuits are designed to minimize water resistance as much as possible. Human bodies are not designed to operate efficiently in the water; our skin is far too porous, creating "drag" when we try to swim. Animals that live in the water, such as sharks, have skin that produces almost no drag. A racing swimsuit tries to mimic this quality, allowing the human body to move through the water with less friction and greater speed.

Speedo, TYR, Arena, Nike and other athletic wear manufacturers all carry racing suits designed to reduce drag. Women's racing suits are very traditional in construction, having two straps and fairly low-cut leg holes. The straps often meet at a single point on the upper back, which prevents them from falling off the shoulders while the wearer is racing. Racing swimsuits are extremely tight, which helps further decrease drag in the water.

As highlighted during the last Olympic Games, there has been a recent revolution in swimsuits designed for racing. The new suits cover the wearer from the neck to just above the knee, or sometimes down to the ankle. The material is lightweight and ultra thin, helping to streamline the wearer's shape. The swimmer's body is compressed in critical areas, which maintains optimal swimming posture and dampens muscle oscillation, making the racer's movements more efficient. These swimsuits also repel water, which further decreases the body's drag. Overall, the new racing suits are so efficient in improving the swimmer's speed that there was actually talk of banning them at the Beijing Olympics. This did not occur, resulting in numerous new speed records. Clearly, these racing suits are in the process of revolutionizing aquatic sports.

Of course, swimsuits are not only worn in the water. One of the only two-piece suits to be used in athletics is the sports bikini, which is favored by professional female beach volleyball players. These bikinis are much more modest than many of their recreational-use-only counterparts. Sports bikini bottoms are fairly basic, modest and resemble the bottoms of other bikinis. The tops, however, provide a great deal more coverage and support than other bikini tops. Sports bikini tops are essentially sports bras, designed to allow the wearer maximum movement without falling off.