When it comes to competitive swimming there are various strokes and distances that can be competed in at most competitions. Competitive swimming started to become increasingly popular in the in the 1800’s , and due to its popularity is and has been for a long time one of the most popular events in the summer Olympics. Competitive swimming has an international governing body that goes by the world recognised name of FINA. The governing body of FINA includes local sub groups such as Amateur Swimming Association (ASA) and Swimming Teachers Association (STA) in the United Kingdom ,USA Swimming (USAS) and United States Masters Swimming (USMS) in the United States. FINA regulates the four swimming disciplines, swum over different distances as outlined below. Freestyle, also known as front crawl’, can be swum using any technique or style the swimmer chooses, although front crawl is swum 99% of the time, and thus in swimming competitions bares no restrictions on what action the swimmers use. The only exception to this is when the swimmer is swimming the freestyle part of an individual medley event. The following events are held for freestyle in distances of 50 m, 100 m, 200 m, 400 m, 800 m and 1500 m. All of these can be swum in regular competitions and major games. Butterfly events require that the swimmer’s actions are equal at both sides