Swimming can require a lot of sacrifice. Most competitive swimmers practice every day, and some have multiple workout sessions several times a week. Swimmers also have to deal with the effects of chlorinated water drying out their skin and hair. At competitive levels, drag can become a key issue and one that may decide the outcomes of races. To best prepare themselves for racing, many swimmers remove hair from their bodies and make adjustments to their attire to eliminate drag and improve their times.
Shave your body. Body hair may create only minor resistance in the water, but when swimming races are won by hundredths of a second, having a smooth body can make a big difference. Hair follicles can create very small amounts of drag all over your body, causing you to slow down slightly in the water. Shaving helps remove the drag.
Shave your head or wear a swim cap to improve aerodynamics. The head is the part of your body that often cuts through the water first, and it is important that minimal drag be created at this point. Most men choose to shave their heads, but girls and women usually opt for rubber caps that hold the hair in and reduce drag.
Wear a skintight swimsuit. Some men, particularly younger men, struggle with trading out baggy swimming trunks in favor of revealing, skintight swimsuits, but swimming with trunks is like pulling a parachute behind you when running. They are not an option at competitive levels. Another option is to wear swimsuits that cover your entire lower body, or even the upper body as well, similar to a wetsuit. However, these types of swimsuits are not allowed at all levels of competition.
Improve and refine your swimming technique to help streamline the body and reduce drag. Swimming stroke techniques are designed to provide advantages to the swimmer in the water, and proper technique allows the swimmer to minimize the drag created by the body when swimming -- for example, lifting the arm fully out of the water during the upstroke of the American crawl prevents the arm from creating drag. It can take years of practice to perfect these techniques, but they can provide a decided advantage in the water.
Many swimmers choose to keep their body and/or hair unshaven during training in order to practice against the extra resistance, helping to strengthen their swimming muscles. However, they usually wear swim caps during practice to improve sight when in the water.
If you're a fairly new swimmer, practice your technique when a coach or lifeguard is present.