Competition

Competitive swimming became popular in the nineteenth century. The goal of competitive swimming is to beat the competitors in any given event. Swimming in competition should create the least resistance in order to obtain maximum speed. However, some professional swimmers who do not hold a national or world ranking are considered the best in regard to their technical skills. Typically, an athlete goes through a cycle of training in which the body is overloaded with work in the beginning and middle segments of the cycle, and then the workload is decreased in the final stage as the swimmer approaches competition. The practice of reducing exercise in the days just before an important competition is called tapering. A final stage is often referred to as "shave and taper": the swimmer shaves off all exposed hair for the sake of reducing drag and having a sleeker and more hydrodynamic feel in the water

World record holder and Olympic gold medalist Michael Phelps in the 400 IM.

Swimming is an event at the Summer Olympic Games, where male and female athletes compete in 16 of the recognized events each. Olympic events are held in a 50-meter pool, called a long course pool.
There are forty officially recognized individual swimming events in the pool; however the International Olympic Committee only recognizes 32 of them. The international governing body for competitive swimming is the Fédération Internationale de Natation ("International Swimming Federation"), better known as FINA.

Open water

In open water swimming, where the events are swum in a body of open water (lake or sea), there are also 5 km, 10 km and 25 km events for men and women. However, only the 10 km event is included in the Olympic schedule, again for both men and women. Open-water competitions are typically separate to other swimming competitions with the exception of the World Championships and the Olympics.

Swim styles

In competitive swimming, four major styles have been established. These have been relatively stable over the last 30–40 years with minor improvements. The four main strokes in swimming are:

• Butterfly (fly)
• Backstroke (back)
• Breaststroke (breast)
• Freestyle (free)

Events in competition may have only one of these styles except in the case of the individual medley, which contains all four. In this latter event, swimmers swim equal distances of butterfly, then backstroke, breaststroke, and finally, freestyle. In Olympic competition, this event (called the "IM") is swam in these distances - 200 or 400 meters or yards. Some competition also swims the 100 yard or meter IM - particularly, for younger swimmers (typically under 14 years) involved in club swimming, or masters swimming (over 18).

Dolphin kick

In the past two decades, the most drastic change in swimming has been the addition of the underwater dolphin kick. This is used to maximize the speed at the start and after the turns. The first successful use of it was by David Berkoff. At the 1988 Olympics, he swam most of the 100 m backstroke race underwater and broke the world record on the distance during the preliminaries. Another swimmer to use the technique was Denis Pankratov at the 1996 Olympics in Atlanta, where he completed almost half of the 100 m butterfly underwater to win the gold medal. In the past decade, American competitive swimmers have shown the most use of the underwater dolphin kick to gain advantage, most notably Olympic and World medal winners Michael Phelps and Ryan Lochte.
While the dolphin kick is mostly seen in middle-distance freestyle events and in all distances of backstroke and butterfly, it is not usually used to the same effect in freestyle sprinting. That changed with the addition of the so-called "technical" suits around the European Short Course Championships in Rijeka, Croatia in December 2008. There, Amaury Leveaux set new world records of 44.94 seconds in the 100 m freestyle, 20.48 seconds in the 50 m freestyle and 22.18 in the 50 m butterfly. Unlike the rest of the competitors in these events, he spent at least half of each race submerged using the dolphin kick.