Information AboutSwimmer |
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swimmer]] Swimming is a technique to move unaided through Water . This article concentrates on human swimming, a popular recreational activity and a competitive sport. There are many health benefits of swimming, but it also entails risks. HISTORY See Also: History of swimming Swimming has been known since prehistoric times. Drawings from the , and other sagas. In 1538 Nicolas Wynman, German professor of languages, wrote the first swimming Book "Colymbetes". Competitive swimming in Europe started around 1800, mostly using Breaststroke . The Front Crawl , then called the ''trudgen'' was introduced in 1873 by John Arthur Trudgen, copying it from Native American s. Swimming was part of the first modern Olympic Games in 1896 in Athens . In 1902 the ''trudgen'' was improved by Richard Cavill, using the flutter kick. In 1908, the world swimming association Federation Internationale De Natation (FINA) was formed. Butterfly was first a variant of Breaststroke , until it was accepted as a separate style in 1952. TECHNIQUE See Also: The ability to swim The Human Body is composed primarily of water, and thus has a very similar density. But since only roughly 70% of the body is water, it is slightly less dense than the surrounding water, which exerts a buoyant force on it. Thus, staying afloat requires only a slight propelling of water downward relative to the body, and transverse motion only a slight propelling of water in a direction opposite to the direction of intended motion, due to generally low hydrodynamic Drag . This propelling is typically accomplished by cupping the hands and using them as Paddle s, and by kicking the legs to push water away from the body. With practice, technique can convert a slow or average swimmer to at least a moderately fast swimmer. Since speed converts directly into distance, the same techniques that improve speed also aid one to move farther with the same Effort . The torso and the legs should be kept as much as possible parallel to the surface of the water. Dropped legs or a slanted torso dramatically increase drag. The hand should be extended forward of the head as much as possible. This increases the average length at the water-line, substantially increasing speed. This is an effect long used by boat designers, and unconsciously used by "naturally good swimmers." The time spent on the side should be maximized because the torso is narrower front-to-back than side-to-side on most swimmers. This reduces the frontal cross-section, reducing drag further, and also increasing the ratio between the body's water-line-length and width. Similar improvements are possible by orienting the narrowest direction of head, hands, legs and arms into the water. The torso is by far the most critical. The motion of the Hand , arm, and leg from the back to the front should be in the air for as much as possible, and in the water, oriented as perfectly as possible, because the returning appendage has to move at least twice as fast as the swimmer, and in the water generates eight times the drag (which increases with the cube of the speed) of an equal amount of torso frontal area. The basic "catch" of the water is not nearly as critical as the above items. Most swimmers simply grab water with their hand flat, or the fingers slightly spread, and then draw it smoothly down their body. None of the above techniques require improved strength. With strength training, the hands and feet can be extended further into the water, gaining more propulsion. For beginners, increased strength brings only small improvements if the above strategies (minimising drag and lengthening water-line) are not optimal. A number of Swimming Styles have been developed based on the implementation of some or all of these principles. COMPETITIVE SWIMMING Competitive swimming is swimming with the goal to maximize performance, usually the speed of swimming. Competitive swimming became popular in the nineteenth century, and currently comprises 32 events at the Summer Olympic Games . Competitive swimming's international governing body is FINA . RECREATIONAL SWIMMING The most common reason for swimming is probably recreation, where the swimmer enters the water merely for enjoyment. Swimming is a good way to relax. Many Swimming Styles are suitable for recreational swimming. Most recreational swimmers prefer a style that keeps their head out of the water and uses an underwater arm recovery. For example, Breaststroke , Side Stroke , or ' Dog Paddle ', however, out-of-water recovery of freestyle or Butterfly gives rise to better exploitation of the difference in viscosity of the two media (air and water). Butterfly, which consists of out-of-water recovery with even symmetry in body movements, is most suited to rough water swimming. For example, Vicki Keith crossed the rough waters of Lake Ontario using Butterfly. Most recreational swimming takes place in pools, where the water is calm. Therefore Freestyle (which does not work as well in rough water) is suitable. However, playing around in rough water is a common source of recreation, but is sometimes dangerous due to undertow or the risk of injury from rocks on the bottom of a lake or riverbed. Swimming Pool s are popular venues for recreational swimming, as are beaches, lakes, Swimming Hole s, Creek s, rivers, and sometimes canals. OCCUPATIONAL SWIMMING A number of people enter the water and swim as part of their work. For example, Abalone divers or Pearl divers swim and dive to obtain an economic benefit, as do Spear Fishermen . Swimming is used to rescue other swimmers in distress. There are a number of specialized swimming styles specially for rescue purposes (''see List Of Swimming Styles ''). Such techniques are studied by Lifeguards or members of the Coast Guard . The training of these techniques also evolved into competitions such as Surf Lifesaving . Swimming is also done for scientific research. Swimming is studied to improve the performances of competitive swimmers. Swimming is also used in Marine Biology to observe plants and animals in their natural habitat. Other sciences may also use swimming. Konrad Lorenz for example swam with Geese as part of his studies of Animal Behavior . Swimming also has Military purposes besides the mere need to cross waters. A swimmer in the water or under the water can be difficult to detect, especially at night. Military swimming is usually done by Special Forces , such as Navy SEALS . Swimming is used to approach a location, gather intelligence, sabotage or combat, and to depart a location. This may also include airborne insertion into water or leaving a submerged Submarine through a hatch or the torpedo tubes. Special equipment and techniques are also used to engage hostiles in and under water. Swimming has more recently become a professional sport as well. Companies such as Speedo and Tyr Sports, Inc. sponsor swimmers just as Nike sponsors basketball players. Cash awards are also given at many of the major competitions for breaking records. SWIMMING FOR EXERCISE Swimming is a good form of Exercise . Because the Density of the human body is approximately similar to that of Water , the body is supported by the water and less stress is therefore placed on joints and bones. Furthermore, the Resistance against movement depends heavily on the speed of the movement, allowing the fine tuning of the exercise according to one's ability. Therefore, swimming is frequently used as an exercise in rehabilitation after injuries or for the Disabled . Resistance Swimming is one form of swimming exercise. It is done either for training purposes, to hold the swimmer in place for stroke analysis, or to enable one to swim in a confined space for either athletic or therapeutic reasons. Resistance swimming can be done either against a stream of water set in motion by a (usually) self-contained mechanical device (often termed a '' Swimming Machine '') or by holding the swimmer stationary by means of elastic attachments. Swimming is primarily an Aerobic Exercise due to the relatively long exercise time, requiring a constant Oxygen supply to the muscles, except for short sprints where the muscles work Anaerobically . As with most aerobic exercise it is believed to reduce the harmful effects of Stress . While aerobic exercises usually burn fat and help with losing weight, this effect is limited in swimming, even though being in cold water burns more Food Energy to maintain body temperature. The reason that swimming does not significantly reduce weight is still poorly understood, but seems to be related to the better heat conduction of water. A number of reasons are suspected.
Swimming exercises almost all Muscle s in the body. Usually, the Arm s and upper body are exercised more than the Leg s. In competitive swimming, excessive leg muscles can be seen as a disadvantage as they consume more oxygen, which would be needed for the muscles in the arms, although this depends on the swimming style. While Breaststroke generates significant movement with the legs, Front Crawl propels the body mainly with the arms. Sometimes the swimming consists of swimming laps using a conventional stroke, such as the Front Crawl ; other forms can include different forms of exercise performed in the water, such as Water Aerobics . Swimming may be good for Asthma sufferers. Swimming uses all three energy systems, which are the Creatine Phosphate system, Anaerobic Glycolosis (also known as Lactic Acid system), and the Aerobic system. These three systems require energy in form of ATP to function. HEALTH RISKS Beach.]] Swimming is considered a sport with a low risk of injury. Nevertheless there are some health risks with swimming. Most lethal risks in swimming are due to the inability to swim. It is recommended to swim in an area supervised by Lifeguard s and to pay attention to the water conditions. Possible health risks, ranging from potentially lethal to minor temporary inconveniences include the following:
CLOTHING See Also: Swimsuit The desire or cultural demand of Modesty together with the awkwardness or unsuitability of conventional Clothing in the water led to the development of the Swimsuit (and in Victorian times, the Bathing Machine ). Men's swimsuits tend to be Trunks , surf or Boardshorts , Competition Briefs , or Cut-offs . Other types of swimwear include Speedos . Women's swimsuits are generally either one-piece swimsuits of traditional or competitive style (such as the Racerback ) or Bikini s. Another option would be a Tankini , more conservative than a bikini but still not a one-piece. Bodyskin s are special whole body swimsuits for competitive swimming, designed to reduce skin drag. (See Competitive Swimwear ) Nude or Topless swimming is done:
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