Swimming is a sport, but also a workout for every part of your body. Swimming requires a body of water such as a pool or the ocean. You'll also need a bathing suit and goggles to see underwater. Swimming is popular all around the world and has been around since the beginning of time when humans needed to cross bodies of water.
Swimming was first practiced as a form of training in ancient Greece and Rome, and competitive forms of the sport were documented as early as the first century B.C. in Japan. Some European authorities in the Middle Ages feared that swimming spread infections and caused epidemics, but teaching swimming was mandatory in Japanese schools by the 17th century A.D. The first European swimming organization formed in the 19th century, and swimming made its way into the Olympics for the 1896 games.
Olympic swimming events were only for men until 1912, when women's events were added. Before the formation of FINA, the international swimming federation, in 1909, Olympic swimming events included such things as a 200-meter obstacle course. Modern-day competitive swimming events are typically still measured in meters. Olympic-size pools are 50 meters long.
Races are performed in some combination of one of four strokes: butterfly, backstroke, breaststroke and freestyle. Of these, breaststroke is the earliest to have been practiced. Swimming a certain number of laps of each of the four strokes is known as an individual medley (IM). Modern-day races range from 50 to 1500 meters in distance. Freestyle is raced at distances of 50, 100, 200, 400, 800, and 1,500 meters, and the other three strokes are only raced at distances of 100 and 200 meters. IM is raced at distances of 200 and 400 meters. There are also three relay events, where groups of four swimmers complete a given distance one after the other: there are 4 x 100 and 4 x 200-meter freestyle relays and a 4 x 100 medley relay.
The objective is to finish a distance before the rest of the swimmers in the other lanes. Events begin with the sound of a buzzer, at which time athletes jump into the pool from raised starting blocks, or push off the wall from in the water with backstroke races. Since 1972, world records for races have been measured in hundredths of a second.
Swimmers initially trained by simply swimming as much as possible at every workout. By the 1950s, this became replaced by interval training. Interval training workouts involve swimming the same distance repeatedly, with controlled amounts of rest in between.