Of the four swim techniques used in competition (the others being breaststroke, backstroke, and freestyle), the butterfly is the most recently invented, dating back to 1933. It is the fastest of the four competitive swim styles but also one of the hardest as it requires near perfect technique and extremely strong shoulder strength for it to be workable. The butterfly’s unforgiving nature when it comes to technique leads to many coaches listing it as the most difficult of the four main swim styles.
The butterfly is performed from a starting position on the chest with the arms extended above the head and the legs straight back. The propulsion of the butterfly is created by synchronous motion in both the arms and the legs. From the starting position, the arms are moved similar to the breaststroke. With palm outward, the arms are arced back until they create a Y-shape with the torso.
From this position, the arms are quickly pulled downward towards the torso, keeping the palms facing downward to catch water and push the body forward. Once the arms are down by the swimmers side, immediately pull them slightly above the surface of the water and return them to the starting position. While the arms repeat the above motion, the legs are moved in what is referred to as a “dolphin kick”. To perform the dolphin kick, the legs and feet are kept together and moved in an up-down motion as though it were the tail of a dolphin, hence the name of the kick.
The butterfly is one of the fastest swim method used in competition. With proper technique, a swimmer can swim the butterfly up to 2.18 meters/second. In competition, the butterfly is performed in 50, 100, and 200-meter races.