Devoir de Philosophie

Swimming.

Publié le 14/05/2013

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Swimming. I INTRODUCTION Swimming, act of moving through the water by using the arms, legs, and body in motions called strokes. The most common strokes are the crawl, backstroke, breaststroke, butterfly, and sidestroke. Swimming is an integral part of almost all water-based activities. It is also a competitive sport itself. Some scientists believe that human beings are born with an instinctive ability to use their arms and legs to stay afloat. That instinct, however, disappears within a few months after birth. Later in life many children and adults learn to swim in order to be safe around the water, to have fun, and to participate in competition. II SWIMMING FUNDAMENTALS People can swim in any body of water large enough to permit free movement. These areas include ponds, lakes, rivers, the ocean, and pools. Most people enjoy swimming in water that is between 18° and 29°C (64° and 84°F). A Learning to Swim In many parts of the world, people learn to swim by imitating others, most often their parents, brothers, sisters, and friends. Most youngsters in North America also take lessons at swim clubs, community centers, schools, or recreational facilities. In addition, the American Swimming Coaches Association (ASCA) and the American Red Cross sponsor programs that teach children about water safety. Instructors teach students skills that will make them safe, efficient, and confident swimmers. Beginners first put their heads in the water and blow bubbles by exhaling. Gradually, students progress to floating, treading water, and ultimately, learning the techniques of the major strokes. Students use various pieces of equipment during these lessons. Water-wings are inflatables worn around the upper arms; they allow children to float easily. Kickboards are buoyant boards that students can rest their arms on; this keeps their upper bodies afloat and allows them to concentrate on kicking correctly. Pull-buoys are foam floats that swimmers hold between their thighs to keep the lower body high and flat on the surface of water; using them, students can learn the arm and upper body movements of various strokes. Paddles are small, firm boards fitted over the hands; they force students to pull their arms through the water correctly. Fins worn on the feet allow swimmers to go faster and to develop proper body position and power. B Hazards and Safety Measures Individuals should not swim in conditions that their ability and experience will not allow them to handle. For inexperienced recreational swimmers, many safety hazards exist--even in a pool. These hazards include misjudging a dive and hitting one's head on the bottom, holding one's breath too long, becoming exhausted, and experiencing sudden cramps while too far from shore or other swimmers. In rivers and oceans, all swimmers should respect the power of nature. Powerful waves, tides, and currents can easily overpower even the most experienced swimmers, sweeping them out beyond safety or throwing them into coral or rocks. Caves pose additional dangers because swimmers can be trapped inside them. Swimmers must follow the instructions of lifeguards and obey posted information about water conditions, tides, and other dangers such as jellyfish or pollution. A good precaution for children is the buddy system, in which each child is paired with another while in the water. This system ensures that no person is swimming alone and that if an emergency does happen, the lifeguard can be notified immediately. III THE MAJOR STROKES Four of the five main swimming strokes--the crawl, backstroke, breaststroke, and butterfly--are used both in competition and recreation. The fifth major stroke, the sidestroke, is slower than the competitive strokes and is used primarily as a recreational and life-saving technique. A Crawl The crawl is the fastest and most efficient swimming technique. It is also called the freestyle, because swimmers use it in freestyle events, which allow the use of any stroke. To swim the crawl, a swimmer travels through the water with the chest and head pointing downward toward the bottom. The legs move in a flutterkick, moving up and down quickly and continually. Each arm stroke begins as the right arm is brought in front and slightly to the right of the swimmer's head and into the water. When the right hand enters the water, the right elbow should be above the surface of the water and the body should be tilted slightly to the left side. At the same time, the left arm accelerates underneath the water in a pulling motion down the length of the body. After the right arm enters the water, the body naturally rolls to the right so that the body is horizontal to the water surface. The left arm continues through the stroke at the swimmer's side. The swimmer continues to extend the right arm forward, and the body begins to roll onto its right side. As the right arm begins to pull the swimmer forward, it increases the body's tilt to the right side, and the left arm exits the water near the swimmer's hip. The swimmer then brings the left arm forward to enter the water while the right arm travels down the swimmer's side. As the left arm enters the water and the right arm exits, the swimmer's body begins to turn to the left side again, and the swimmer begins the stroke sequence once more. In the crawl, turning the head to breathe is a simple, easy motion that should be coordinated with the body roll. As the body tilts completely to the right or left side, the swimmer should roll the head to the same side and take a breath. After inhaling, the swimmer puts his or her face back in the water, looking toward the bottom of the pool. The swimmer exhales slowly through the nose or mouth as the body rolls toward the other side. B Backstroke The backstroke is the only stroke that is swum on the back, with the swimmer looking up. Backstroke swimmers therefore cannot see where they are going. Because the face is out of the water, swimmers need no special breathing technique. Backstrokers use the same flutterkick that crawl swimmers do. At the beginning of each arm stroke, the swimmer extends the right arm so it enters the water slightly to the right of the head. The palm should be facing away from the swimmer and the pinky finger should enter the water first. At the same time, the swimmer moves the left arm through the water below the left side of the body. Once in the water, the right arm begins pulling the swimmer forward by bending at the elbow. At the same time the swimmer holds the left arm straight as it reaches the hip and lifts it out of the water. As the right arm continues to pull, the swimmer rotates slightly onto the right side and swings the left arm up above the head. As the swimmer finishes the right arm's stroke along the body, he or she begins to rotate toward the left side as the left arm reaches to enter the water above the head. As the left hand enters the water, the body completes its roll to the left side and the right arm lifts out of the water. Continuing these motions, the swimmer moves forward. C Breaststroke The breaststroke is one of the easiest and most relaxing strokes for novices. Competitive swimmers, however, find it difficult because it uses more energy than the crawl and backstroke when swum at a fast pace. The breaststroke has undergone major changes since it was introduced in the 17th century. Most swimmers now use a technique called the wave breaststroke, which Hungarian coach Jozsef Nagy developed in the late 1980s. To swim the wave breaststroke, the swimmer enters the water with the body streamlined, facing the pool bottom with arms and legs fully extended. To begin the stroke, the swimmer sweeps the arms out with the hands facing outward and bent slightly upward at the wrist. When the swimmer's body and arms form a T-shape, the swimmer bends each arm at the elbow. The elbows remain near the surface of the water, while the forearms and hands, pointing toward the bottom of the pool, sweep inward and underneath the chin. The swimmer shrugs the shoulders, looks down, and arches the back as the arm sweep pulls the body forward. The swimmer then raises the feet to the surface of the water, bends the knees, and spreads the legs. The thighs should remain in line with the body. As the head and upper torso clear the surface of the water, the swimmer inhales and lunges forward with the arms. During this movement the swimmer turns the feet outward and kicks backward. The swimmer then returns to the basic streamlined position and repeats the stroke. D Butterfly The butterfly stroke is powerful, graceful, and fast. More than any other stroke, the butterfly relies on good technique. Developed between 1930 and 1952, the butterfly is swum with an undulating motion. The arms are brought forward over the water's surface, then brought back together in front of the body simultaneously. Each arm stroke is complemented by two dolphin kicks, meaning the feet are kept together and brought down then up again, much like the motion of a dolphin's tail. The swimmer begins the butterfly with the body in the basic streamlined position and the head facing downward. The arms enter the water with the hands facing outward, as the swimmer lunges forward, submerging the head and chest slightly. At this point the swimmer makes a light downward kick with both feet. The body glides forward, and the hands catch water and begin to pull. The pulling stroke begins with the hands facing outward and the elbows near the water surface. The swimmer pulls the hands down so that they come together under the body. The legs start the second downward kick. When the swimmer then pulls the arms down to the hips, the motion forces the head and shoulders above the surface of the water. This positioning enables the swimmer to inhale. The swimmer finishes the arm pull with a sweeping motion that brings each arm along the sides with the palms facing in. When the second downward kick is completed, the swimmer swings the arms slightly out of the water and glides forward. Another stroke cycle begins as the swimmer plunges the arms back into the water above the head. E Sidestroke The sidestroke evolved out of the breaststroke technique in the 19th century, primarily because swimmers wanted to swim faster. Swimmers originally thought that because the body remained on one side throughout the sidestroke cycle, there would be less resistance. However, because the sidestroke generates less force than the other strokes, it turned out to be slower. The sidestroke has remained a popular recreational stroke for novices. It is also used as a life-saving technique because the lifesaver's head remains above the water at all times and one arm stays free to help the distressed swimmer. The sidestroke's propulsion comes mainly from the legs in a movement called a scissors kick, because the legs are brought together powerfully like the shears of a pair of scissors. The arms provide some propulsion but mainly serve to stabilize the body on its side. The swimmer starts the sidestroke by balancing the body on either the right or the left side. The head, back, and legs are straight, with the feet and toes pointed. The bottom arm extends ahead of the swimmer under the water, while the top arm is placed along the side, so that the hand is at the upper thigh. The face stays just above the surface to allow easy breathing. The swimmer moves the lower arm downward and then draws it back to the body and toward the feet in a sweeping motion. This pulls the body slightly forward. At the same time, the swimmer flexes the hips and knees, and brings the heels slowly up toward the buttocks. As the arms and hands come together near the chest, the swimmer extends the legs straight then brings them together in a powerful thrust. The swimmer returns to the starting position as the body glides through the water. When the glide begins to slow, the swimmer repeats the stroke cycle. IV COMPETITIVE SWIMMING Competitive swimming is one of the most popular participant sports in the world. In the United States alone, more than 250,000 individuals belong to the sport's governing organization, USA Swimming. Many leagues exist for competitive swimmers, including ones sponsored by summer programs, cities, Young Men's Christian Association (YMCA) chapters, Jewish Community Center (JCC) chapters, high schools, colleges, and Masters Swim programs. A Pools Pools for competition come in two basic sizes. Short-course pools measure 25 yd (22.8 m) or 25 m (27.3 yd) in length. (The United States is the only country that conducts competition in 25-yd pools.) Long-course pools measure 50 m (54.6 yd) in length. Most major swimming events take place in 50-m pools. Most pools for high-level competition have eight lanes--one for each swimmer. (Many public pools or pools at recreational facilities have only six lanes.) The lanes extend the full length of the pool and range up to 2.5 m (8 ft 2 in) wide. Floating plastic lane markers separate the lanes, reduce turbulence, and help each competitor swim in a straight line. Each lane also has a line painted on the bottom. This line serves as a visual reference for the competitor when swimming with the head down. At 5 m (5.5 yd) before each wall, the line becomes a T, signaling the swimmers how far they are from the wall, so that they can prepare their turns or their finish. Also at 5 m, a line of flags is strung across the width of the pool, providing the same information to backstrokers. Pools used for competition also have lines at the sides of the pool at the 15-m (16.4-yd) mark. Used by judges during competition, these lines indicate the farthest distance a swimmer is allowed to swim under water after the start and when making a turn. Crawl, breaststroke, and butterfly competitors begin racing by diving from starting blocks that are 75 cm (30 in) above the surface of the water. Backstroke swimmers start in the water by holding on to the side of the pool in a crouched position, and then lunging backward away from the wall. At most high-level competitions, electronic timing devices record how long each competitor takes to complete the course. The device starts timing when the starter's horn goes off. Each lane has an electronic touch pad on the wall that the swimmer pushes when completing the race. The pad stops the timing device and records the swimmer's time in a computer. The score is then transferred to a scoreboard that the swimmers, fans, and judges can see. Each lane also has a timekeeper with a handheld stopwatch, in case the electronic timing device fails. All timing is done to the hundredth of a second, and many races are decided by small margins. B Equipment In competition, swimmers wear a swimsuit, a swim cap, and goggles. Swimsuits are made of a material such as Lycra or Spandex that clings tightly to the swimmer but also permits a free range of motion. A swim cap worn over the hair and ears also helps to reduce the resistance a swimmer encounters when moving through the water. Swim goggles allow swimmers to see better under water. They also protect swimmers' eyes from irritation caused by chlorine and other chemicals in the pool water, and from salt or pollution in natural bodies of water. In a sport where races are decided by hundredths of a second, every advantage is important. For major meets, most swimmers shave the body hair off of their arms, legs, and any other surface area that is in contact with the water. This reduces resistance and can lower a swimmer's time by as much as 1 or 2 percent--a significant difference. C Training Most swimmers at the highest levels of competition train for four to five hours a day and five to seven days a week. They typically swim about 10,000 to 20,000 m (6 to 12 mi) per day and supplement their workouts with flexibility exercises, weight training, and other routines. As major competitions near, swimmers spend hours honing their starts and turns, trying to execute them as quickly as possible. They also spend time working on technique so they maintain as streamlined a position as possible. Most swimmers train by doing groups of distances, called sets, following strict instructions. For example, a coach may instruct a team to swim "6 x 400 meters on 5:00, descending 1-3 and 4-6." This means that a swimmer will do six 400-meter swims, one starting every five minutes. If the swimmer completes the first 400-meter segment before five minutes, he or she can rest until the five minutes have elapsed. But the second 400-meter segment must be swum at a faster pace than the first, and the third segment faster than the second. The swimmer then starts over, easing up on the fourth swim, but picking up the pace again for the fifth and sixth segments. Many training regimens exist; all are designed to build strength and endurance. D Swim Meets Swim meets are organized competitions that pit individual swimmers or swimming teams against each other. Most meets feature preliminary races, called heats, that occur before the finals. The top eight swimmers from the preliminaries compete in the finals of each event. In the finals, the fastest swimmers are assigned to the middle lanes. These lanes are considered most desirable because the swimmers in them are most aware of the positions of their competitors. Swimmers in the middle lanes also encounter the least wave action from the water as it travels from the swimmers and bounces off the sides of the pool. During competition, swimmers must obey the starter's commands. When the starter announces "Take your marks," all the swimmers must assume the starting position by crouching on the blocks. The starter's horn (or pistol) then sounds, indicating the start of the race, and the swimmers dive into the water. In most meets, any swimmer who makes a false start by leaving the starting block before the horn sounds is disqualified. In Olympic competition, two false starts are allowed for the competitors as a whole. After these two, any competitor who makes a false start is disqualified. Swimmers are also disqualified for swimming the wrong stroke or for swimming the stroke incorrectly, as judged by officials. Turning incorrectly or failing to surface 15 m after the turn can also lead to disqualification. E Officials Meet officials ensure that the swimmers compete fairly and that the meet is conducted in a safe manner. The number of such officials varies, depending on the level of competition and the number of participants. Generally, meet officials include a starter, a referee, stroke judges, and turn judges. At high-level competitions other officials are responsible for bringing the competitors to the starting blocks and for making swimmers available for drug tests and press interviews after the race. F Events Events take place in the freestyle, backstroke, breaststroke, butterfly, and individual medley. In the individual medley event, the swimmer completes an equal distance of each of the four strokes in this order: butterfly, backstroke, breaststroke, and freestyle. At major national and international competitions, the freestyle events are swum at six different lengths. They are 50-meter, 100-meter, 200-meter, 400-meter, 800meter, and 1,500-meter races. Swimmers race the backstroke, breaststroke, and butterfly at two lengths, 100 meters and 200 meters. Individual medley events are 200 meters and 400 meters in length. Meets also involve relay events, in which four swimmers compete as a team, taking turns swimming equal distances. The team with the fastest combined time wins. The relay events are the 4 × 100-meter freestyle relay, the 4 × 100-meter medley relay, and the 4 × 200-meter medley relay. In the medley relays, the first member of the team swims the backstroke, the second swims the breaststroke, the third swims the butterfly, and the fourth swims the freestyle. At some meets, swimmers not only compete on an individual level but also win points for their teams. The team that scores the most points wins the meet. G Amateur Competition Swimming has many levels of competition. In the United States six official age groups are recognized: 10 and under, 11 to 12, 13 to 14, 15 to 16, 17 to 18, and 19 and over. Each age group has predetermined time standards that ensure that swimmers almost always are competing against others of the same skill level. Other countries have similar age-group systems. State interscholastic organizations govern high school swimming. The National Interscholastic Swimming Coaches Association (NISCA) oversees all national rules for high school competition within the United States. The National Collegiate Athletic Association (NCAA) governs swimming at the collegiate level. College teams swim against one another at dual meets (involving two teams) or invitationals (involving several teams). Individual swimmers who meet qualifying standards in an event advance to the NCAA championships, which are held each March. The championships determine the national individual champion of each event as well as the team champion. Smaller colleges and universities compete in national meets governed by the National Association of Intercollegiate Athletics (NAIA) or the National Junior College Athletic Association (NJCAA). In many countries, adult swimmers who are no longer eligible for collegiate events compete at the Masters Swim level, which organizes events in five-year age groups such as 35 to 39, 40 to 44, and so on. Thousands of Masters Swim meets are held across the United States each year, including one short course (25-m) and one long course (50-m) national championship. Every two years the Masters world championship occurs, featuring more than 1,500 of the world's best adult swimmers. Representing more than 50 countries, the competitors range in age from 25 to 90. H International Competition The highest level of swimming competition occurs at the Summer Olympic Games, held every four years and governed by the International Olympic Committee (IOC). The Fédération Internationale de Natation Amateur (FINA; French for "International Federation of Amateur Swimming") governs almost all other international competitions. The two most important meets are the long-course (50-m) world championships and the short-course (25-m) world championships, which are held in alternate years. Each winter, FINA also sponsors a World Cup circuit held in 25-m pools. Many regional meets are held every two or four years. These include the Pan-Pacific Championships for nations in Asia and the Pacific Ocean region, the European championships, the Pan American Games for the countries of North and South America, and the African championships. To participate in international meets, a swimmer must be selected by his or her national federation. Many countries base the selection on performances at national championships or Olympic trials. In addition, swimmers must meet international time standards predetermined by FINA. However, each country is allowed to select one swimmer per event regardless of the swimmer's times. V OTHER SWIMMING ACTIVITIES Swimming is integral to several sports, including body boarding, snorkeling, surfing, synchronized swimming, triathlon, underwater diving, and water polo. People also should have strong swimming skills in a variety of other water-based activities, including competitive diving, fishing, jet-skiing, rowing, sailing, and waterskiing. Swimming is a valuable activity for physical therapy and exercise. Because it works the majority of the muscles in the body and provides both aerobic benefits and resistance benefits (as the swimmer pulls and pushes through the water), the sport is generally considered one of the most complete forms of exercise. Swimming does not strain joints and connective tissue as much as many other forms of exercise, and swimmers injure themselves at a lower rate than most other athletes. Athletes in other sports who are recovering from injuries often swim to stay in shape. Several exercise programs are water based. In water aerobics, the water provides extra resistance for cardiovascular workouts. Many older adults exercise by becoming involved in programs with organized coaching, workouts, and competition. Swimming laps in pools is an extremely popular exercise among people of all ages. Not all competitions take place in pools. In long-distance swimming, racers compete over lengthy courses, usually in lakes, rivers, or the ocean. Most competitions are held at distances of 5 and 25 km (3.1 and 15.5 mi), but some races are longer than 38 km (24 mi). The longest races can take seven or eight hours to complete. Several occupations require that individuals be proficient swimmers. For lifeguards, swimming skills are perhaps most important because lifeguards are responsible for the safety of other people in swimming areas. Scuba diving and snorkeling instructors also must be prepared to assist others if an emergency occurs. Physical education teachers must swim well enough to teach others. Underwater archaeologists do research while scuba diving, so strong swimming skills help them with their work. Pearl divers must be able to swim deep and hold their breath for a long time as they descend to the bottom to search for their treasures. Sailors and offshore oil workers do not swim as part of their jobs, but because they work on the water, they should be able to swim fairly well in case they accidentally fall overboard. VI HISTORY Human beings have been swimming for thousands of years. One of the earliest representations of swimming is an ancient Egyptian wall relief that shows soldiers of Pharaoh Ramses II (reigned 1290-1224 BC) pursuing their enemies by swimming across the Orontes River between ancient Egypt and Asia Minor. Swimming was highly esteemed in ancient Greece and Rome, especially as a form of training for warriors. In Japan, competitions were held as early as the 1st century BC. In Europe, swimming was less popular during the Middle Ages (5th century to 15th century), when immersion in water was sometimes associated with the recurrent epidemic diseases of the time. The crawl stroke was probably invented independently in various areas of the world several hundred years ago. Swimmers in South America and the South Pacific used crawl-like strokes long before they were used in Europe. Native Americans also used an overarm crawl stroke. In 1844 two members of the Native American Ojibwa tribe named The Flying Gull and Tobacco traveled to England, where they defeated local champions and became national celebrities. By the 19th century European misconceptions about the dangers of swimming had been dispelled. In the late 19th century amateur swimming clubs began conducting competitions in the United States and Britain. In the United States, colleges and universities such as Yale University, Indiana University, and the University of Southern California played an important role in spreading interest in swimming as a competitive sport. In 1875 Matthew Webb of Great Britain became the first person to swim across the English Channel (see Channel Swimming). Webb swam between Dover, England, and the coast of France near Calais, where the channel is more than 32 km (20 mi) in width. By 1896 swimming had become well established. It was one of the sports at the first modern Olympic Games, held that year in Athens, Greece. A Early Champions At the 1904 Olympics in St. Louis, Missouri, American swimmer Charles Daniels won gold medals in the 200-meter and 400-meter freestyle, signaling the beginning of an era of American dominance that lasted until the 1930s. Women's swimming became an Olympic sport at the 1912 Games in Stockholm, Sweden, and Australian swimmer Fanny Durack won the first gold medal in the 100meter freestyle. That same year American swimmer Duke Kahanamoku won the men's 100-meter freestyle. Kahanamoku repeated his 100-meter victory at the 1920 Games in Antwerp, Belgium, and was also a member of the winning 4 × 200-meter freestyle relay team. Later, Kahanamoku traveled worldwide as a Red Cross water safety instructor, promoting swimming and the sport of surfing. At the 1924 Olympics in Paris, France, Kahanamoku finished second in the 100-meter freestyle to fellow American Johnny Weissmuller. Weissmuller also won gold medals in the 400-meter freestyle and the 4 × 200-meter freestyle relay. That same year American swimmers Ethel Lackie and Martha Norelius won gold medals in the 100-meter and 400-meter freestyle races, respectively. In the 400-meter freestyle relay, Lackie and teammates Euphrasia Donnelly, Gertrude Ederle, and Mariechen Wehselau captured the gold medal. Two years later, in 1926, Ederle swam across the English Channel, becoming the first woman to do so. Her time for the 56-km (35mi) crossing from Cap Gris-Nez, France, to Dover, England, was 14 hours 31 minutes, breaking the previous record of 16 hours 23 minutes. In 1928 Weissmuller repeated his 100-meter and 4 × 200-meter victories at the Olympics in Amsterdam, Netherlands. Japanese swimmers ended American dominance by winning five of the six men's events at the 1932 Olympic Games in Los Angeles, California. Buster Crabbe, one of the most famous male swimmers of the period, won the only gold medal for the American men, in the 400-meter freestyle. American women continued to be successful. Leading female swimmers included Eleanor Holm and Helene Madison of the United States and Hendrika Mastenbroek of The Netherlands. Swimming became more popular in the United States in the 1940s and 1950s, partly due to American swimmer and actor Esther Williams. Because the Olympics were cancelled during World War II (1939-1945), Williams never competed in the Olympics competition, but she starred in a number of popular motion pictures that featured her in water ballets, swimming, diving, and waterskiing. She went on to develop her own line of swimming pools. In the 1950s and 1960s Australian swimmers enjoyed great Olympic success, including Murray Rose, Jon Konrads, David Thiele, and Dawn Fraser. Fraser became the first Olympic champion to win the same event at three different Olympics when she captured the gold medal in the 100-meter freestyle at the 1956 Games in Melbourne, Australia, the 1960 Games in Rome, Italy, and the 1964 Games in Tokyo, Japan. B Champions Since the 1970s At the 1972 Olympics in Munich, West Germany, American swimmer Mark Spitz produced one of the greatest athletic feats in Olympic history. Spitz won seven gold medals, all in world-record times. He remains the only swimmer ever to win seven gold medals at one Olympics. American swimmers John Naber and Bruce Furniss were two of the men's stars at the 1976 Olympics in Montréal, Québec, Canada, while swimmers from East Germany won almost all the gold medals in the women's competition. In 1972 and 1976, American Shirley Babashoff won a total of eight Olympic medals (two gold and six silver). The 1980 and 1984 Olympics, held in Moscow and Los Angeles respectively, were both affected by large boycotts involving numerous countries, and many athletes did not compete. Outstanding performers from these Games included Vladimir Salnikov of the Union of Soviet Socialist Republics (USSR), Barbara Krause of East Germany, Michael Gross of West Germany, and Rowdy Gaines and Mary T. Meagher of the United States. At the 1988 Games in Seoul, South Korea, Kristin Otto of East Germany won six gold medals and Janet Evans of the United States won three. American Matt Biondi won five gold medals in the men's events. Also at Seoul, Anthony Nesty of Suriname became the first black Olympic swimming champion when he won the 100-meter butterfly. In the late 1980s and early 1990s Aleksandr Popov of Russia and Krisztina Egerszegi of Hungary emerged as dominant swimmers. At the 1992 Games in Barcelona, Spain, Popov won gold medals in the men's 50-meter and 100-meter freestyle races. He repeated the victories at the 1996 Games in Atlanta, Georgia. Egerszegi won the 200-meter backstroke at three different Olympics: 1988, 1992, and 1996. She also won the 100-meter backstroke and the 400-meter individual medley in 1992. Outstanding American swimmers of the 1980s and 1990s include Mike Barrowman, Pablo Morales, Summer Sanders, and Jenny Thompson. Other swimmers also produced outstanding performances at the 1996 Games, including Amy Van Dyken of the United States and Michelle Smith of Ireland. Van Dyken won gold medals in the 50-meter freestyle, the 100-meter butterfly, the 4 × 100-meter freestyle relay, and the 4 × 100 medley relay. Smith won gold medals in the 400-meter freestyle, 200-meter individual medley, and the 400-meter individual medley. Australian swimmers asserted their dominance of men's long distance events during the 1990s. Kieren Perkins won gold medals in the 1,500-meter freestyle at the 1994 world championships and the 1992 and 1996 Olympics. During the 1998 world championships, Ian Thorpe and Grant Hackett took gold and silver medals in the 400-meter freestyle, and Hackett won a gold medal in the 1,500-meter freestyle. Thorpe was one of the top stars at the 2000 Olympics, held in Sydney, Australia. He won five medals, including gold in the 400-meter freestyle and in the 4 × 100meter and 4 × 200-meter freestyle relays. Other swimming stars at the 2000 Games included Pieter van den Hoogenband of The Netherlands, who won gold medals in the 100-meter and 200-meter freestyle events; Lenny Krayzelburg of the United States, who captured gold medals in the 100-meter and 200-meter backstroke races and the 4 × 100-meter medley relay; and Inge de Bruijn of The Netherlands, who won four medals, including golds in the 50-meter and 100-meter freestyle events and in the 100-meter butterfly. Veteran American swimmers Dara Torres (two gold and three bronze medals) and Thompson (three gold, one bronze) also starred in the Games in Sydney. C Performance-Enhancing Drugs Despite the popularity of swimming as a whole, the use of performance-enhancing drugs has cast a shadow over some of the individual accomplishments in the sport. Beginning in 1994, various reports of use of performance-enhancing drugs by the East German and Chinese women's teams surfaced. In the 1970s and 1980s members of the East German team, including Kristin Otto, were systematically given drugs--sometimes without their knowledge--by their coaches. Many of these athletes later suffered major health problems. In the mid-1990s evidence of drug use was also found among Chinese female swimmers. At the 1994 world championships, Chinese women won almost every event. Three weeks later, seven Chinese swimmers tested positive for banned steroids during a surprise drug test. During the late 1990s more Chinese women tested positive for drug use and one Chinese swimmer was arrested for carrying a large quantity of bioengineered human growth hormone into Australia on the way to the 1998 world championships. Also in 1998, Ireland's Michelle Smith was found guilty of tampering with her urine sample during a surprise drug test. She was suspended from competitive swimming for four years. Rumors about the use of illegal performance-enhancing drugs by swimmers continued at the 2000 Olympics, prompting calls for more research on detection. D Recent Developments Swimming techniques evolve constantly as swimmers search for ways to improve their performances. During the late 1980s American swimmer David Berkoff perfected a technique called the underwater dolphin. He found that he could swim faster by staying under water, streamlining his body, and dolphin-kicking on his back for about 30 to 40 m (33 to 43 yd). Eventually, backstroke and butterfly swimmers adopted the technique. The result was that swimmers spent much of their races under water. In 1998 FINA limited the distance a swimmer could swim under water to 15 m at the start and after each turn, returning emphasis to stroke technique. International events featured several new formats during the 1990s. The 1998 Goodwill Games used a highly successful dual meet format in which teams competed against each other in a round-robin tournament. In several countries, including Brazil and Australia, events that feature competitive swimmers racing for cash and prizes are popular with television audiences. In open water swimming, Australia's Susie Maroney performed several feats previously thought impossible. In 1997 she became the first person to swim the 169-km (105-mi) strait between Havana, Cuba, and Key West, Florida. The following year she completed a 206-km (128-mi) swim from Isla Mujeres, Mexico, to Las Tumbas beach in Cuba. In 1999 Maroney swam the 160-km (100-mi) distance from Jamaica to Cuba. Contributed By: Phillip Whitten Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.

« the swimmer and the pinky finger should enter the water first.

At the same time, the swimmer moves the left arm through the water below the left side of the body.Once in the water, the right arm begins pulling the swimmer forward by bending at the elbow.

At the same time the swimmer holds the left arm straight as it reachesthe hip and lifts it out of the water.

As the right arm continues to pull, the swimmer rotates slightly onto the right side and swings the left arm up above the head. As the swimmer finishes the right arm’s stroke along the body, he or she begins to rotate toward the left side as the left arm reaches to enter the water above thehead. As the left hand enters the water, the body completes its roll to the left side and the right arm lifts out of the water.

Continuing these motions, the swimmer movesforward. C Breaststroke The breaststroke is one of the easiest and most relaxing strokes for novices.

Competitive swimmers, however, find it difficult because it uses more energy than thecrawl and backstroke when swum at a fast pace.

The breaststroke has undergone major changes since it was introduced in the 17th century.

Most swimmers now use atechnique called the wave breaststroke, which Hungarian coach Jozsef Nagy developed in the late 1980s. To swim the wave breaststroke, the swimmer enters the water with the body streamlined, facing the pool bottom with arms and legs fully extended.

To begin thestroke, the swimmer sweeps the arms out with the hands facing outward and bent slightly upward at the wrist.

When the swimmer’s body and arms form a T-shape,the swimmer bends each arm at the elbow.

The elbows remain near the surface of the water, while the forearms and hands, pointing toward the bottom of the pool,sweep inward and underneath the chin.

The swimmer shrugs the shoulders, looks down, and arches the back as the arm sweep pulls the body forward.

The swimmerthen raises the feet to the surface of the water, bends the knees, and spreads the legs.

The thighs should remain in line with the body. As the head and upper torso clear the surface of the water, the swimmer inhales and lunges forward with the arms.

During this movement the swimmer turns the feetoutward and kicks backward.

The swimmer then returns to the basic streamlined position and repeats the stroke. D Butterfly The butterfly stroke is powerful, graceful, and fast.

More than any other stroke, the butterfly relies on good technique.

Developed between 1930 and 1952, thebutterfly is swum with an undulating motion.

The arms are brought forward over the water’s surface, then brought back together in front of the body simultaneously.Each arm stroke is complemented by two dolphin kicks, meaning the feet are kept together and brought down then up again, much like the motion of a dolphin’s tail. The swimmer begins the butterfly with the body in the basic streamlined position and the head facing downward.

The arms enter the water with the hands facingoutward, as the swimmer lunges forward, submerging the head and chest slightly.

At this point the swimmer makes a light downward kick with both feet.

The bodyglides forward, and the hands catch water and begin to pull. The pulling stroke begins with the hands facing outward and the elbows near the water surface.

The swimmer pulls the hands down so that they come together underthe body.

The legs start the second downward kick. When the swimmer then pulls the arms down to the hips, the motion forces the head and shoulders above the surface of the water.

This positioning enables theswimmer to inhale. The swimmer finishes the arm pull with a sweeping motion that brings each arm along the sides with the palms facing in.

When the second downward kick is completed,the swimmer swings the arms slightly out of the water and glides forward.

Another stroke cycle begins as the swimmer plunges the arms back into the water above thehead. E Sidestroke The sidestroke evolved out of the breaststroke technique in the 19th century, primarily because swimmers wanted to swim faster.

Swimmers originally thought thatbecause the body remained on one side throughout the sidestroke cycle, there would be less resistance.

However, because the sidestroke generates less force than theother strokes, it turned out to be slower.

The sidestroke has remained a popular recreational stroke for novices.

It is also used as a life-saving technique because thelifesaver’s head remains above the water at all times and one arm stays free to help the distressed swimmer. The sidestroke’s propulsion comes mainly from the legs in a movement called a scissors kick, because the legs are brought together powerfully like the shears of a pairof scissors.

The arms provide some propulsion but mainly serve to stabilize the body on its side. The swimmer starts the sidestroke by balancing the body on either the right or the left side.

The head, back, and legs are straight, with the feet and toes pointed.

Thebottom arm extends ahead of the swimmer under the water, while the top arm is placed along the side, so that the hand is at the upper thigh.

The face stays justabove the surface to allow easy breathing. The swimmer moves the lower arm downward and then draws it back to the body and toward the feet in a sweeping motion.

This pulls the body slightly forward.

At thesame time, the swimmer flexes the hips and knees, and brings the heels slowly up toward the buttocks.

As the arms and hands come together near the chest, theswimmer extends the legs straight then brings them together in a powerful thrust.

The swimmer returns to the starting position as the body glides through the water.When the glide begins to slow, the swimmer repeats the stroke cycle. IV COMPETITIVE SWIMMING Competitive swimming is one of the most popular participant sports in the world.

In the United States alone, more than 250,000 individuals belong to the sport’sgoverning organization, USA Swimming.

Many leagues exist for competitive swimmers, including ones sponsored by summer programs, cities, Young Men’s ChristianAssociation (YMCA) chapters, Jewish Community Center (JCC) chapters, high schools, colleges, and Masters Swim programs. A Pools Pools for competition come in two basic sizes.

Short-course pools measure 25 yd (22.8 m) or 25 m (27.3 yd) in length.

(The United States is the only country thatconducts competition in 25-yd pools.) Long-course pools measure 50 m (54.6 yd) in length.

Most major swimming events take place in 50-m pools. Most pools for high-level competition have eight lanes—one for each swimmer.

(Many public pools or pools at recreational facilities have only six lanes.) The lanes extendthe full length of the pool and range up to 2.5 m (8 ft 2 in) wide.

Floating plastic lane markers separate the lanes, reduce turbulence, and help each competitor swim in. »

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