Swimming is one of the top public recreational activities. In few countries, swimming lessons are a compulsory part of the educational curriculum.
There are many reasons why people swim, from swimming as a recreational pursuit to swimming as a necessary part of a job or other activity. Swimming may also be used to rehabilitate injuries, especially various cardiovascular injuries and muscle injuries. As a formalized sport, swimming features in a range of local, national, and international competitions, including every modern summer Olympics, which takes place every four years.
The best part of swimming is it doesn`t tire you as much as other recreational activities for fitness. This is because human body is only slightly less dense than water, water supports the weight of the body during swimming. As a result, swimming is `low-impact` compared to land activities such as running. The density and viscosity of water also create resistance for objects moving through the water. Swimming strokes use this resistance to create propulsion, but this same resistance also generates drag on the body.
Swimming as a sport is an individual or team sport that involves using arms and legs to move the body through water. Typically, the sport takes place in pools or in open-water (e.g., in a sea or lake). Competitive swimming is one of the most popular Olympic sports, with events in butterfly, backstroke, breaststroke, freestyle, and individual medley. In addition to these individual events, swimmers also take part in relays. Swimming each stroke requires specific techniques, and in competition, there are specific regulations concerning the acceptable form for different strokes.