Devoir de Philosophie

Diving (sport).

Publié le 14/05/2013

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Diving (sport). I INTRODUCTION Diving (sport), act of plunging into water headfirst or feetfirst from diving boards, poolsides, the shore, docks, or cliffs. People dive as a way to enter the water, but they also dive for fun and in competition, attempting to perform airborne acrobatics before entering the water gracefully. This article addresses the sport of competitive diving from diving springboards and platforms. For information on scuba diving, Diving (underwater). Water depth is usually well marked in pools, but in natural bodies of water the depth is usually not indicated. To decide whether or not a location is safe for diving, anyone planning to dive should first check the depth of the water and make sure it is free from underwater obstructions. At an unfamiliar location, divers should ease into the water slowly and feetfirst. In competitive diving, divers perform basic dives, somersaults, and twists, which they complete with an entry into the water. Separate events are held for platform divers, who dive from a fixed, rigid platform, and springboard divers, who dive from a narrower, springy board that flexes under weight and movement. Event heights range from 1-m (3.2-ft) low springboards to 10-m (32.8-ft) high platforms. Judges evaluate each dive and assign a score. II DIVING TECHNIQUES A basic dive has four distinct phases: the starting position, the take-off, the in-flight maneuvers, and the entry into the water. Divers learn each of these components by repeating the dive or skill over and over. Divers also use skill progressions to learn more difficult dives. They first master simple skills such as feetfirst jumps before learning body positions, alignment, somersaults, and twists. These complex skills are often taught on dry land using special equipment such as trampolines combined with safety harnesses that can suspend the diver in the air with ropes. Foam pits that cushion landings from low springboards are also used. A Starting Position Each dive begins from a starting position, and there are two basic types of starts: standing and running. For standing dives the diver stands on the edge of the platform or springboard with the body held straight, the head erect, and the arms straight. In front and reverse dives from the standing position, the diver looks forward out over the pool. In back and inward dives, the diver turns around to face the platform or springboard. For so called running dives, the diver takes the starting position far enough back from the edge of the platform or tip of the springboard to take a few steps and build up forward momentum before take-off. While in the starting position, divers relax, think about the movements they will do, and visualize themselves completing the dive perfectly. A referee signals for the dive to begin, usually by blowing a whistle. In a standing dive, the diver moves straight into the take-off without a bounce. In a running dive, the diver first moves into the approach, which must be at least four steps long. The approach should be smooth, straight, and without hesitation. B Take-Off The take-off is the portion of the dive prior to flight when the diver prepares to jump up and away from the platform or springboard. Because the take-off determines the diver's path through the air, divers at all levels must respond quickly to mistakes at take-off to make corrections and complete the dive as intended. Platform divers begin the take-off with a squat, then jump high and away from the platform. Springboard divers make an initial hop before taking off, then land on the board with both feet while it flexes down and back up. This allows them to capture the force in the board's recoil and launch themselves high in the air. C Flight The in-flight maneuvers define which dive the athlete is performing. During the passage through the air, a diver can hold his or her body in one of several positions. These positions are straight, pike, tuck, and free. In all four positions, flexibility and strength play a role in whether the dive is on target or a miss. A diver must be flexible enough to move in and out of these positions while completing twists and somersaults, and strong enough to hold the position while spinning rapidly. In the straight position, a diver may not bend the body at the hips or the knees. In the pike position, a diver bends at the hips while keeping the legs straight at the knees. In both the straight and pike positions the diver's arm position is optional. In the straight position the arms may be held above the head or at the sides. The closed pike position has the diver touching the ankles or grabbing the legs with the hands. During an open pike, the hands remain at the diver's sides. In the tuck position the diver folds the body into a compact ball, bent at the knees and hips with the knees together, and with the hands on the lower legs. In the free position, a diver may use any or all of the other positions. In all positions the diver should hold the feet together and keep the toes pointed. Divers can make a variety of dives from these four positions. The jackknife is a front dive in the pike position, in which the diver bends at the hips on the ascent to the highest point of the dive, then straightens before entering the water headfirst. Forward somersaulting dives, in which the diver executes one or more somersaults before entering the water headfirst or feetfirst, usually start in the pike or tuck position. A tight tuck or pike position enables the diver to spin faster. The reverse dive, or half gainer, begins with a front takeoff, but as the diver jumps forward to clear the board he or she reverses the direction of rotation and spins back toward the board, performing a half-somersault. The diver then enters the water headfirst facing the board. The reverse somersault, also called a full gainer, is a back somersault in which the diver begins from a front takeoff, rotates back toward the board, and enters the water feetfirst. Another dive is the inward dive, or cutaway, in which the diver stands backward on the board during take-off and spins toward the board, entering the water headfirst. The forward, backward, reverse, and inward dive groups form the basis for competitive diving, and advanced divers perform combinations or variations on these somersaulting dives. The dives increase in complexity and difficulty as the level of competition rises. Some Olympic divers can perform up to four and one-half somersaults or twists in a dive. For all divers, performing multiple somersaults and twists may cause the athlete to become disoriented, losing sense of where he or she is in the air. To avoid this problem, many divers focus their eyes on certain spots in the pool area during each rotation; this helps them reference their position. D Entries Divers have less than two seconds in the air to complete the dive. During this time they must complete their rotations and line the body up to enter the water in a nearly vertical position. During a headfirst entry divers clasp their hands overhead and interlock their thumbs. The divers also lock the elbows, elevate the shoulders to the ears, form a slightly curved body shape, and tighten the body muscles. From this body position, a diver can make a rip entry, and avoid a large splash. As the diver enters the water, there is a small initial splash followed by an upjet of water that creates a larger, more noticeable splash after the diver's body displaces water under the surface. To minimize this upjet, top-level divers make a quick swimming motion by releasing their hands and collapsing their arms as they submerge. Instead of a large splash, the surface of the water appears to boil as the air bubbles rise from the diver's entry. For feetfirst entries, which are rare in top-level competitions, divers place their legs and feet together while pointing their toes down towards the water. The neck and head are held as if looking straight ahead. III DIVING FACILITIES AND EQUIPMENT Diving facilities provide enough room for athletes to complete dives without colliding with the ceiling, poolsides, pool walls, or pool bottom. The Fédération Internationale de Natation Amateur (FINA, International Federation of Amateur Swimming), which serves as the governing body for Olympic diving, recommends minimum dimensions for diving facilities. A Platforms Platform competitions use three heights: 5 m (16.4 ft), 7.5 m (24.6 ft), and 10 m (32.8 ft). The platforms vary in width and length depending on their height. The 10-m platform is 2 m (6.6 ft) wide and 6 m (19.7 ft) long. A nonslip material covers the surface and the front edge of the platform, and handrails surround the back and sides. Many pools have stacked platforms, with one platform built directly above another. The platform above projects a minimum of 76 cm (30 in) beyond the platform below, so that the diver does not hit the lower one on the way down. Collegiate divers may use all three platform heights during competition. In platform competitions at the Olympic Games, world championships, and World Cup, 10 m is the standard height. B Springboards Competitive springboards are 1 m (3.3 ft) and 3 m (9.8 ft) above the surface of the water. They are made of an aluminum alloy and measure 4.9 m (16 ft) long and .5 m (1.6 ft) wide. Springboards hang over the pool at least 1.5 m (5 ft) beyond the edge. The last portion of the board is made of a lightweight material that minimizes the potential for serious injury if a diver accidentally hits it with the hands, arms, feet, or head. High school divers use 1-m springboards. Both 1-m and 3-m boards are used in collegiate competitions, as well as the world championships and World Cup. Olympic springboard diving is limited to the 3-m competition. C Other Rules The diver must be able to see the surface of the water during the dive, and FINA has several requirements to ensure this. Springboards and platforms in outdoor pools must face north in the northern hemisphere and south in the southern hemisphere; this avoids glare from the sun, which lies to the south in the northern hemisphere and to the north in the southern hemisphere. For indoor pools and for diving at night in outdoor pools, lighting must be sufficient. Any sources of illumination should prevent glare. A smooth surface of water can make it difficult for athletes to judge the distance to the water. Therefore, many competition pools have machines that agitate the water under the springboards and platforms, making the surface more visible. Some pools that host major events have elevators that take divers to the top of the platform and underwater windows below the surface of the pool for observers and television cameras. D Designation and Degree of Difficulty Divers submit a list of dives they intend to perform prior to competition. Every dive is indicated in a code of three or four numbers followed by a single letter. Each of these indicators represents an aspect of the dive and tells the judges what dive they will be scoring. Before each dive, the dive number is displayed visibly to divers and judges. To prepare young divers for competition, coaches test the students' knowledge in practice by referring to the dive by number rather than description. IV COMPETITION The number of dives in a competition varies by age group. Olympic and world championship competitions have three sessions. Before the first session, called the preliminaries, the dive order is randomly selected and posted for the divers to see. During the preliminaries divers perform a list of dives without regard to degree of difficulty. Men perform six dives and women perform five. The top 18 divers advance to the next session, the semifinals, and follow the same dive order. Each diver performs another list of dives that may not exceed the degree of difficulty established by the rules. Men and women diving from the 3-m springboard perform five dives, while only four dives are performed from the 10-m platform. The preliminary and semifinals scores are then added together and the top 12 divers advance to the finals. In the finals, divers compete in the reverse order of their standing, with the lowest-scoring diver going first. Men perform six dives while women perform five dives. After the finals are completed, the semifinals scores and finals scores are added together. The diver who scores the most points wins the competition. A Scoring a Dive Each dive has a degree of difficulty. Points are assigned to five areas: somersaults, flight position, twists, approach, and entry. The degree of difficulty of each dive is calculated according to a formula that adds points for each of these categories. Rulebooks provide a list of previously calculated degrees of difficulty for about 75 different dives on the springboard and about 100 different dives on the platform. When a diver performs a new dive, the competition's officials assign it a number and determine its difficulty using a specific formula. The dive is then registered with FINA. At most diving competitions a panel of five judges scores each dive and awards points. The Olympic Games and world championships use seven judges. After each dive the judges immediately and simultaneously indicate the points they award to the diver without communicating with one another. The judges rate the technique and execution of the dive, including the starting position, run, take-off, flight, and entry. Whole points or half points are awarded from zero to ten according to the opinion of the judges as follows: Completely failed: 0 points Unsatisfactory: 0.5-2.0 points Deficient: 2.5-4.5 points Satisfactory: 5.0-6.0 points, Good: 6.5-8.0 points Very Good: 8.5-10.0 points Judges subtract points, called deductions, when a dive is completely or partially performed in a position other than the one listed. No points are awarded when a diver executes a dive with a different dive number than listed or makes no dive at all. To determine a diver's total score, the highest and lowest judges' marks are canceled. The total of the remaining marks is multiplied by the degree of difficulty. In competitions with seven judges, the total score is divided by five, and then multiplied by three. This yields a score that can be compared to dives scored by a five-judge panel. For example: Five Judges' Awards - (High Score and Low Score) = Total × Difficulty = Score 8 + 7 + 7 + 7 + 6.5 - (8 and 6.5) = 21 × 2.0 = 42.0 Seven Judges' Awards Total - (High Score and Low Score) = Subtotal × Difficulty = Second Subtotal ÷ 5 = Total × 3 = Score 8 + 7 + 7 + 7 + 7 + 7 + 6.5 - (8 and 6.5) = 35 × 2.0 = 70 ÷ 5 = 14 × 3 = 42.0 B Governing Bodies Diving events are held for many different age groups. FINA governs international competitions. In the United States several organizations supervise the various levels of competition: the National Federation of State High School Associations (NFHS), the National Junior College Athletic Association (NJCAA), the National Collegiate Athletic Association (NCAA), and United States Diving, Inc., which selects and prepares the teams that represent the United States in international competition. V HISTORY Diving has been a human activity as long as swimming has been, from simple entries into the water to jumps for fun from natural high points such as cliffs and outcroppings. During the 1800s diving headfirst into the water to swim became popular, and a sport called plunging developed. Participants would plunge from the side of a pool or dock or any other high point above the water, hold their breath, and glide beneath the water for as far as possible. From 1893 to 1937, plunging championships were held, and the plunge was an event at the 1904 Olympic Games in St. Louis, Missouri. Diving evolved as plunging participants attempted take-offs from greater and greater heights. In Europe and the United States, bridges served as locations from which to plunge. In Acapulco, Mexico, jumps and dives from high cliffs into the sea were attempted when the tide came in. In Hawaii, people jumped, dived, and somersaulted from great heights into deep pools at the bottom of waterfalls. The modern sport of diving originated in Germany and Sweden at the beginning of the 19th century. At this time, people began moving gymnastics equipment outside onto beaches during the summer months. There, athletes practiced routines from flying rings, trapezes, and springboards built on high platforms, landing in the water after aerial maneuvers. The trapeze and rings were eventually discarded and diving from platform and springboard alone became popular. The sports were named springboard diving, plain high diving, and fancy high diving. Competitive diving first gained international prominence in the early 20th century, when men's plain high diving debuted as an Olympic event at the 1904 Games. Springboard diving joined the Games four years later in London, England. Men's fancy high diving and women's plain high diving became Olympic sports at the 1912 Games in Stockholm, Sweden. The women's event, however, prohibited the twists and somersaults that made the men's fancy high diving competition exciting. Women's springboard diving joined the Olympics at the 1920 Games in Antwerp, Belgium. By the 1928 Games in Amsterdam, Netherlands, men's plain and fancy diving events were combined into one event. Rules were also adopted that allowed women to use twists and somersaults. Divers from Germany and Sweden dominated early international competition. After Swedish coach Ernst Bransten immigrated to the United States, however, American divers improved dramatically. Bransten introduced dry-land training, in which he mounted a diving board over a sandpit, enabling divers to practice the approach and take-off, then land feetfirst. Using this form of training, divers could practice more repetitions in a shorter time period, without getting wet. During the 1920s Bransten's work resulted in a series of successful American divers, including Al White, who won gold medals in the men's springboard and platform diving at 1924 Games in Paris, France, and Pete Desjardins, who did the same at the 1928 Games. Another prominent American coach was Mike Peppe, who headed the swimming and diving program at Ohio State University from 1931 to 1963. Peppe treated swimming and diving with equal importance and encouraged other schools do the same. His influence on college programs resulted in improved facilities for diving, more practice time for divers, greater respect for the sport, and the hiring of specialized diving coaches. From the 1932 Games in Los Angeles, California, through the 1956 Games in Melbourne, Australia, American men and women won gold medals in each diving event except the 1956 men's platform competition. One notable Olympic performer was Sammy Lee, who won gold medals in men's platform in 1948 in London, England, and in 1952 in Helsinki, Finland. In the women's events, Pat McCormick won four gold medals, capturing springboard and platform titles in both 1952 and in 1956. During the 1960s and 1970s, American divers began to share the world stage with Europeans. Bob Webster of the United States won the platform titles at the 1960 Games in Rome, Italy, and the 1964 Games in Tokyo, Japan, but in the women's competition German diver Ingrid Kramer rose to prominence. She won three gold medals, capturing the springboard and platform titles in 1960 and repeating her victory in the springboard in 1964. Italian diver Klaus Dibiasi also won three gold medals, all in the men's platform: in 1968 in Mexico City, Mexico; in 1972 in Munich, Germany; and 1976 in Montréal, Québec, Canada. American divers dominated Olympic 3-m springboard competition during the 1960s and 1970s. Gary Tobian took the gold medal in 1960, followed by Ken Sitzberger in 1964; divers Bernie Wrightson and Sue Gossick won gold medals in 1968; Micki King took the gold in the 1972; and Phil Boggs and Jennifer Croudler captured gold medals in 1976. American diver Greg Louganis dominated men's competition during the 1980s. He had won a silver medal in men's platform diving at the 1976 Games and then missed the 1980 Games in Moscow, Russia, because of a boycott by the U.S. team, but he won gold medals in springboard and platform at both the 1984 Games in Los Angeles and the 1988 Games in Seoul, South Korea. In the 1980s Chinese divers emerged as the top divers in the women's events. With the exception of Canadian diver Sylvie Bermier's springboard gold medal in 1984, Chinese divers placed first at every Olympic competition from 1984 through 1996. Outstanding Chinese divers included Gao Min, who won springboard gold medals at the 1988 Games and the 1992 Games in Barcelona, Spain, and Fu Mingxia, who won her first gold in 1992 on the platform and then won both springboard and platform at the 1996 Games in Atlanta, Georgia. A Recent Developments In 1999 the International Olympic Committee approved synchronized diving as a sport at the 2000 Olympic Games in Sydney, Australia. The ruling allowed for two events (3-m springboard and 10-m platform) for both men and women. In synchronized diving, a pair of divers form a team that simultaneously dives from the same height. Over five rounds, pairs must perform one round with forward facing take-offs by both divers, one round with backward facing take-offs by both divers, and one round with one diver taking off forward and one taking off backward. In the other two rounds, take-off position is optional. Judges score each individual diver's execution, as well the synchronization of the pair's performance. Judges consider factors such as the approach and the take-off; the similarity of height the divers reach during the dive; the coordinated timing of the movements during the flight; the similarity of the angles of the entries; the comparative distance from the board at entry; and the coordinated timing of the entries. Contributed By: Janet L. Gabriel Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.

« water that creates a larger, more noticeable splash after the diver’s body displaces water under the surface.

To minimize this upjet, top-level divers make a quickswimming motion by releasing their hands and collapsing their arms as they submerge.

Instead of a large splash, the surface of the water appears to boil as the airbubbles rise from the diver’s entry. For feetfirst entries, which are rare in top-level competitions, divers place their legs and feet together while pointing their toes down towards the water.

The neck andhead are held as if looking straight ahead. III DIVING FACILITIES AND EQUIPMENT Diving facilities provide enough room for athletes to complete dives without colliding with the ceiling, poolsides, pool walls, or pool bottom.

The Fédération Internationalede Natation Amateur (FINA, International Federation of Amateur Swimming), which serves as the governing body for Olympic diving, recommends minimum dimensionsfor diving facilities. A Platforms Platform competitions use three heights: 5 m (16.4 ft), 7.5 m (24.6 ft), and 10 m (32.8 ft).

The platforms vary in width and length depending on their height.

The 10-mplatform is 2 m (6.6 ft) wide and 6 m (19.7 ft) long.

A nonslip material covers the surface and the front edge of the platform, and handrails surround the back andsides.

Many pools have stacked platforms, with one platform built directly above another.

The platform above projects a minimum of 76 cm (30 in) beyond the platform below, so that the diver does not hit the lower one on the way down.

Collegiate divers may use all three platform heights during competition.

In platform competitionsat the Olympic Games, world championships, and World Cup, 10 m is the standard height. B Springboards Competitive springboards are 1 m (3.3 ft) and 3 m (9.8 ft) above the surface of the water.

They are made of an aluminum alloy and measure 4.9 m (16 ft) long and .5m (1.6 ft) wide.

Springboards hang over the pool at least 1.5 m (5 ft) beyond the edge.

The last portion of the board is made of a lightweight material that minimizesthe potential for serious injury if a diver accidentally hits it with the hands, arms, feet, or head.

High school divers use 1-m springboards.

Both 1-m and 3-m boards areused in collegiate competitions, as well as the world championships and World Cup.

Olympic springboard diving is limited to the 3-m competition. C Other Rules The diver must be able to see the surface of the water during the dive, and FINA has several requirements to ensure this.

Springboards and platforms in outdoor poolsmust face north in the northern hemisphere and south in the southern hemisphere; this avoids glare from the sun, which lies to the south in the northern hemisphereand to the north in the southern hemisphere.

For indoor pools and for diving at night in outdoor pools, lighting must be sufficient.

Any sources of illumination shouldprevent glare. A smooth surface of water can make it difficult for athletes to judge the distance to the water.

Therefore, many competition pools have machines that agitate the waterunder the springboards and platforms, making the surface more visible.

Some pools that host major events have elevators that take divers to the top of the platformand underwater windows below the surface of the pool for observers and television cameras. D Designation and Degree of Difficulty Divers submit a list of dives they intend to perform prior to competition.

Every dive is indicated in a code of three or four numbers followed by a single letter.

Each ofthese indicators represents an aspect of the dive and tells the judges what dive they will be scoring.

Before each dive, the dive number is displayed visibly to divers andjudges.

To prepare young divers for competition, coaches test the students' knowledge in practice by referring to the dive by number rather than description. IV COMPETITION The number of dives in a competition varies by age group.

Olympic and world championship competitions have three sessions.

Before the first session, called thepreliminaries, the dive order is randomly selected and posted for the divers to see.

During the preliminaries divers perform a list of dives without regard to degree ofdifficulty.

Men perform six dives and women perform five.

The top 18 divers advance to the next session, the semifinals, and follow the same dive order.

Each diverperforms another list of dives that may not exceed the degree of difficulty established by the rules.

Men and women diving from the 3-m springboard perform fivedives, while only four dives are performed from the 10-m platform.

The preliminary and semifinals scores are then added together and the top 12 divers advance to thefinals.

In the finals, divers compete in the reverse order of their standing, with the lowest-scoring diver going first.

Men perform six dives while women perform fivedives.

After the finals are completed, the semifinals scores and finals scores are added together.

The diver who scores the most points wins the competition. A Scoring a Dive Each dive has a degree of difficulty.

Points are assigned to five areas: somersaults, flight position, twists, approach, and entry.

The degree of difficulty of each dive iscalculated according to a formula that adds points for each of these categories.

Rulebooks provide a list of previously calculated degrees of difficulty for about 75different dives on the springboard and about 100 different dives on the platform.

When a diver performs a new dive, the competition’s officials assign it a number anddetermine its difficulty using a specific formula.

The dive is then registered with FINA. At most diving competitions a panel of five judges scores each dive and awards points.

The Olympic Games and world championships use seven judges.

After each divethe judges immediately and simultaneously indicate the points they award to the diver without communicating with one another.

The judges rate the technique andexecution of the dive, including the starting position, run, take-off, flight, and entry.

Whole points or half points are awarded from zero to ten according to the opinionof the judges as follows: Completely failed: 0 pointsUnsatisfactory: 0.5-2.0 pointsDeficient: 2.5-4.5 pointsSatisfactory: 5.0-6.0 points, Good: 6.5-8.0 pointsVery Good: 8.5-10.0 points. »

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