Diving
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- This article refers to the sport of jumping into water, often acrobatically. For swimming below the surface of the water, see underwater diving. For other meanings of the term, see dive.
Diving refers to the sport of acrobatically jumping or falling into water. Diving is an internationally-recognized sport that is part of the Olympic Games. In addition, unstructured and non-competitive diving is a common recreational pastime in places where swimming is popular.
While not a particularly popular participant sport, diving is one of the more popular Olympic sports with spectators. Successful competitors possess many of the same characteristics as gymnasts and competitive cheerleaders, including strength, flexibility, kinaesthetic judgment and air awareness.
In the recent past, the success and prominence of Greg Louganis led to American strength internationally. More recently, the greatest diving nation has been China, which came to prominence several decades ago when the sport was revolutionized by national coach Boxi Liang. China has lost few world titles since. Other powers are generally those which import Chinese coaches, including Australia and Canada.
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[edit] Competitive Diving
Most diving competitions consist of three disciplines: 1m, 3m and tower, aka platform.ɳ Competitive athletes are divided by gender, and often by age groups as well. In tower events, competitors are allowed to perform their dives on either the five, seven and a half (generally just called seven) or ten metre towers, although high level meets, including the Olympic Games and world championships, usually require all dives to be executed from the ten metre.
One and three meter dives are performed from a springboard. Five through ten meter dives are performed from concrete or wooden platforms, and such platforms also exist at one and three metre heights as training tools.
Divers must perform a set number of dives according to various established requirements, including somersaults and twists in various directions and from different starting positions (see Components of a Dive below). Divers are judged on whether and how well they completed all aspects of the dive, the conformance of their body to the requirements of the nominated dive, and the amount of splash created by their entry to the water (less being better). A perfect entry, with no splash, is called a "rip," after the loud tearing sound it creates, and is usually accompanied by a "pop" caused by the diver's hands impacting the water (as well as a sometimes painful bursting feeling on the hands of the diver). A bad entry, in which the diver enters the water at an angle not nearly vertical, is called a "wash". In some cases, the diver lands completely horizontal, in what casually would be called a "belly flop" but most divers refer to as a "smack". Theoretically, a score out of ten is supposed to be broken down into three points for the takeoff, three for the flight, and three for the entry, with one more available to give the judges flexibility. However, since judges must give their scores instantaneously, they base their scores more on a gut instinct and overall impression than actual calculations.
The raw score is multiplied by a difficulty factor, derived from the number and combination of movements attempted. The diver with the highest total score after a sequence of dives (which depend on age group and skill level in elite competition) is declared the winner.
While diving is closely related to gymnastics, it differs in one large way: Male and female gymnasts compete vastly different skills on vastly different apparatus, while male and female divers compete the same dives on the same boards. Women are often required to perform one fewer dive than men (10 as opposed to 11, or 5 as opposed to 6), but there has been a movement in recent years to change this fact.
Synchronized diving was adopted as an Olympic sport in 2000. In this event, two divers form a team and attempt to perform dives simultaneously. The dives are usually identical; however, sometimes the dives may be opposites, in what is called a pinwheel. This is an impressive spectacle, and requires great coordination between the team-mates. In these events, synchronicity is valued as highly as technical skill. Thus, if both divers perform their individual dives badly, but in the same way, they will still score fairly well.
[edit] Scoring the Dive
Ultimately, the judges' scores given on each dive are subjective. However, there are specific rules governing how a dive is supposed to be scored. Usually a score factors three elements of the dive: the approach, the flight, and the entry. The primary not be too far away, but should ideally be within 2 feet of the board/platform), (3) the properly defined body position of the diver according to the dive being performed, including pointed toes and feet touching at all times, (4) the proper amounts of rotation and revolution upon completion of the dive and entry into the water, and (5) angle of entry (a diver should enter the water straight, without any angle). Many judges award divers for the amount of splash created by the diver on entry, with less splash resulting in a higher score.
To reduce the subjectivity of scoring in major meets, panels of five or seven judges are assembled. In the case where five judges are assembled, the highest and lowest scores are discarded and the middle three are summed and multiplied by the DD (Degree of Difficulty -- determined from a combination of the moves undertaken, in which position and from what height). In major international events, seven judges are assembled. In these circumstances, the highest and lowest scores are again discarded and the middle five are summed, then ratioed by 3/5, and multiplied by the DD, so as to provide consistent comparison with 5-judge events. Accordingly, it is extremely difficult for one judge to manipulate scores.
There is a general misconception about scoring and judging. In serious meets, the absolute score is somewhat meaningless. It is the relative score, not the absolute score that wins meets. Accordingly, good judging implies consistent scoring across the dives. Specifically, if a judge consistently gives low scores for all divers, or consistently gives high scores for the same divers, the judging will yield fair relative results and will cause divers to place in the correct order. However, absolute scores have significance to the individual divers. Besides the obvious instances of setting records, absolute scores are also used for rankings and qualifications for higher level meets.
[edit] Competitive Strategy
To win dive meets, divers create a dive list in advance of the meet. To win the meet the diver must accumulate more points than other divers. Usually simple dives with low DDs will look good to spectators but will not win meets. The competitive diver will attempt the highest DD dives possible with which they can achieve consistent, high scores. If divers are scoring 8 or 9 on most dives, it may be a sign of their extreme skill, or it may be a sign that their dive list is not competitive, and they may lose the meet to a diver with higher DDs and lower scores.
In competition, divers must submit their lists beforehand, and past a certain deadline (usually when the event is announced shortly before it begins) they cannot change their dives under any circumstances. If they fail to perform the dive announced, even if they physically cannot execute the dive announced, even if they perform a more difficult dive, they will receive a score of zero. Under exceptional circumstances, a redive may be granted, but these are exceedingly rare (usually for very young divers just learning how to compete, or if some event outside the diver's control has caused them to be unable to perform).
There are some American meets which will allow changes of the position of the dive even after the dive has been announced immediately before execution, but these are an exception to the rules generally observed internationally.
Generally, NCAA rules allow for dives to be changed while the diver is on the board, but the diver must request the change directly after the dive is announced. This applies especially in cases where the wrong dive is announced. If the diver pauses during his or her hurdle to ask for a change of dive, it will be declared a balk and the change of dive will not be permitted.
Under FINA law, now dive may be changed after the deadline for the dive-sheet to be submitted (generally a period ranging from one hour to 24 hours, dependending on the rulings made by the event organiser.
It is the diver's responibility to ensure that the dive-sheet is filled in correctly, and also to correct the referee or announcer before the dive if they describe it incorrectly. If a dive is performed which is as submitted but not as (incorrectly) announced, it is declared failed and scores zero according to a strict reading of the FINA law. But in practice, a re-dive would usually be granted in these circumstances.
[edit] Diving and Other Sports
In the United States scholastic diving is almost always part of the school’s swim team. Diving is a separate sport in Olympic and Club Diving. The NCAA will separate diving from swimming in special diving competitions after the swim season is completed.
Divers do not consider themselves swimmers. Sometimes in High School meets, a diver must swim, but often they don't practice swimming. While each sport shares a pool, and may compete side by side when doing so for their schools, the two sports are very different. Swimming is about times, diving is about art; swimming is a full body exercise with emphasis on upper body strength and speed, diving is a full body exercise with emphasis on grace and execution; swimmers most frequently suffer overuse injuries, divers most frequently suffer impact injuries or strains. And, of course, swimming takes place in the water, and diving takes place in the air.
The sister sport of diving is in fact gymnastics and cheerleading. Many divers begin their training as gymnasts or cheerleaders, and switch sports for one reason or another. Two of the most common are that they simply prefer diving, or that they develop a chronic injury that makes continuing gymnastics impossible. Gymnastics and cheerleading provides young divers with unique skills that help them perform complex and risky dives, but there are downsides; some habits developed in gymnastics and cheerleading can interfere with the correct technique of diving.
[edit] Safety
There is a general perception of Diving as being a dangerous activity, and this has contributed to the decline in availability of facilities. In fact, despite the apparent risk, the statistical incidence of injury in supervised training and competition is extremely low.
The majority of accidents that are classified as 'diving-related' are incidents caused by individuals jumping from structures such as bridges or piers into water of inadequate depth.
[edit] Dive Groups
There are six "groups" into which dives are classified: Forward, Back, Inward, Reverse, Twist, and Armstand. The latter applies only to Platform competitions, whereas the other five apply to both Springboard and Platform.
- In the Forward Group (Group 1), the diver takes off facing forwards and rotates forwards
- In the Back Group (2), the diver takes off with their back to the water and rotates backwards
- In the Reverse Group (3), the diver takes off facing forwards and rotates backwards
- In the Inward Group (4), the diver takes off with their back to the water and rotates forwards
- Any dive incorporating an axial twisting movement is in the Twist group (5).
- Any dive commencing from a handstand is in the Armstand group (6).
[edit] Dive positions
During the flight of the dive, one of the four positions may be specified:
- Straight - with no bend at the knees or hips
- Pike - with knees straight but a tight bend at the hips
- Tuck - body folded up in a tight ball, hands holding the shins and toes pointed.
- Free - Some sequence of the above positions.
These positions are referred to by the letters A, B,C and D respectively.
[edit] Dive Numbers
In competition, the dives are referred to by a schematic system of three- or four-digit numbers. The letter to indicate the position is appended to the end of the number.
The first digit of the number indicates the dive group as defined above.
For groups 1 to 4, the number consists of three digits. The third digit represents the number of half-somersaults. The second one is either 0 or 1; with 1 signifying a "flying" variation of the basic movement: ie the first half somersault is performed in the straight position, and then the piked or tucked shape is assumed.
For example:
- 101A - Forward Dive Straight
- 203C - Back one-and-a-half somersaults, tuck
- 307c - Reverse three-and-a-half somersaults, tuck
- 113B - Flying forward one-and-a-half somersaults, pike
For Group 5, the dive number has 4 digits. The second one indicates the group (1-4) of the underlying movement; the third digit indicates the number of half-somersaults, and the fourth indicates the number of half-twists.
For example:
- 5211A - Back dive, half twist, straight position.
- 5337D - Reverse one and a half somersaults with three and a half twists, in the Free position.
For Group 6 - Armstand - the dive number has either three or four digits: Three digits for dives without twist and five for dives with twists.
In non-twisting armstand dives, the second digit indicates the direction of rotation (0 = no rotation, 1 = forward, 2 = backward, 3 = reverse, 4 = inward) and the third digit indicates the number of half-somersaults. Inward-rotating armstand dives have never been performed, and are generally regarded as physically impossible.
For example:
- 600 - Armstand dive
- 612 - Amstand forward somersault
- 624 - Armstand back double somersault
For twisting Armstand dives, the second digit is a five to denothe twisting, the third indicates the direction of rotation - as above, the fourth is the number of half-somersaults, and the fifth the number of half-twists:
e.g. 65221 - armstand back somersault with one-half twist
All of these dives come with DD (degree of difficulty) this is an indication of how difficult/complex a dive is. The score that the dive receives is multiplied by the DD (also known as tariff) to give the dive a final score. Before a diver competes they must decide on a "list" this is a number of optional dives and compulsory dives. The optionals come with a DD limit, this means that you must select X number of dives and the combined DD limit must be no more than the limit set by the competition/organisation etc.
[edit] Mechanics of Diving
At the moment of take-off, two critical aspects of the dive are determined, and cannot subsequently be altered during the execution. One is the trajectory of the dive, and the other is the magnitude of the angular momentum.
The speed of rotation - and therefore the total amount of rotation - may be varied from moment to moment by changing the shape of the body, in accordance with the law of conservation of angular momentum.
The center of mass of the diver follows a parabolic path in free-fall under the influence of gravity (ignoring the effects of air resistance, which are negligible at the speeds involved).
[edit] Trajectory
Since the parabola is symmetrical, the travel away from the board as the diver passes it is twice the amount of the forward travel at the peak of the flight. Excessive forward distance to the entry point is penalised when scoring a dive, but obviously an adequate clearance from the diving board is essential on safety grounds.
The greatest possible height that can be achieved is desirable for several reasons:
- The height attained is itself one of the factors that the judges will reward.
- A greater height gives a longer flight time and therefore longer to execute the moves.
- For any given clearance when passing the board, the forward travel distance to the entry point will be less for a higher trajectory.
[edit] Control of rotation
The magnitude of angular momentum remains constant throughout the dive, but since
-
- angular momentum = rotational velocity × moment of inertia,
and the moment of inertia is larger when the body has an increased radius, the speed of rotation may be increased by moving the body into a compact shape, and reduced by opening out into a straight position.
Since the tucked shape is the most compact, it gives the most control over rotational speed, and dives in this position are easier to perform. Dives in the straight position are hardest, since there is almost no scope for altering the speed, so the angular momentum must be created at take-off with a very high degree of accuracy. (A small amount of control is available by moving the position of the arms and by a slight hollowing of the back).
Notice that the opening of the body for the entry does not stop the rotation, but merely slows it down. The vertical entry achieved by expert divers is largely an illusion created by starting the entry slightly short of vertical, so that the legs are vertical as they disappear beneath the surface. A small amount of additional tuning is available by 'entry save' techniques, whereby underwater movements of the upper body and arms against the viscosity of the water affect the position of the legs.
[edit] Twisting
Dives with multiple twists and somersaults are some of the most spectacular movements, as well as the most challenging to perform.
The rules state that twisting 'must not be generated manifestly on take-off'. This leaves a puzzle of how a twisting movement can be generated in free-fall without any purchase for applying a turning force. The solution is that some of the somersaulting angular momentum is resolved to produce the twisting action.
[edit] Entry
The rules state that the body should be vertical, or nearly so, for entry. The arms must be beside the body for feet-first dives and extended forwards in line for "head-first" dives. It used to be common for the hands to be interlocked with the fingers extended towards the water, but a different technique has become favoured during the last few decades. Now the usual practice is for one had to grasp the other with palms forward to strike the water with a flat surface (the so-called "rip entry"). Surprisingly, this produces less splash than attempting to hold the hands in a "streamlined" position.
[edit] Diving Venues
Divers can compete in several venues; the categories listed below refer only to diving in the United States. Each may have age and experience limitations.
[edit] Summer Diving
In the United States, summer diving is usually limited to one meter diving at community or country club pools. Some pools organize to form intra-pool competitions. These competitions are usually designed to accommodate all school-age children. One of the largest and oldest competitions in the United States is found in the Northern Virginia area where 47 pools compete against each other every summer (with over 380 divers in NVSL's "Cracker Jack" meet).
[edit] High School Diving
In the United States scholastic diving at the high school level is usually limited to one meter diving (But some schools use 3 meter springboards.). Scores from those one meter dives contribute to the swim team's overall score.
In each state there are usually two high school venues. The first is the public school competitions. The second is the independent school venue. In the United States public schools rarely compete with independent schools (see ISL) and almost never compete at the state championship level.
[edit] Club Diving
In the United States, pre-college divers interested in three meter or tower diving should consider a club sanctioned by USA Diving or AAU Diving. Top club divers are usually called "junior Olympic," or JO divers. JO divers compete for spots on national teams. Divers over the age of 19 years of age cannot compete in these events as a JO diver.
USA Diving sanctions one East-West one and three meter event in the winter time with an Eastern champion and Western champion determined. In the summer USA Diving sanctions a national event with tower competitions offered.
AAU Diving sanctions one national event per year in the summer. AAU competes on the one, three, and tower to determine the All-American team.
[edit] College Diving
In the United States scholastic diving at the college level requires one and three meter diving. Scores from the one and three meter competition contribute to the swim team's overall meet score. College divers interested in tower diving may compete in the NCAA separate from swim team events. NCAA Divisions II and III do not usually compete platform; if a diver wishes to compete platform in college, he or she must attend a Division I school.
A number of colleges and universities offer scholarships to men and women who have competitive diving skills. These scholarships are usually offered to divers with age-group or club diving experience.
The NCAA limits the number of years a college student can represent any school in competitions. The limit is four years, but could be less under certain circumstances.
The University of Texas at Austin is an exceptionally famed college concerning its diving program, with some of the worlds greatest divers hailing from there. Laura Wilkinson being the most famous of them, there are still many more that are generated every year.
[edit] Master Diving
In the United States divers who continue diving past their college years can compete in Master Diving programs. Master diving programs are frequently offered by college or club programs.
Masters' Diving events are normally conducted in age bands of 5 or 10 years, and attract competitors up to 80+ years of age on occasion. European Masters' Championships are held annually and World Masters' Championships are held biennially. These attract an enthusiastic following in all age-groups. In Britain National Masters' Championships are held two or three times per year.
[edit] British Diving
In Britain, diving runs throughout the year as it does in all countries. However in Britain there is no discipline restrictions with regards to only competing 1m in the summer etc. They compete all boards all year round. Age groups have different limits of heights of platform available to compete on, depending on age and competence; meaning that some divers may have to dive up an age group depending on ability.
Group D (11 & under): 5m
Group C (12/13 year): 5m & 7.5m
Group B (14/15 year): 5m, 7.5m & 10m
Group A (16/18 year): 5m, 7.5m & 10m
(These are FINA-specified Age-Groups, and so not limited to Britain).
This means that Group C divers, if capable are eligible to dive in Group B is they wish to compete on the 10m platform.
[edit] Famous Divers
[edit] Olympic and World Cup Divers
- Australia: Rebecca Gilmore, Mathew Helm, Chantelle Newbery, Robert Newbery, Dean Pullar, Melissa Wu and Loudy Tourky
- Canada: Annie Pelletier, Myriam Boileau, Philippe Comtois, Alexandre Despatie, Blythe Hartley, Émilie Heymans, and Anne Montminy
- China: Fu Mingxia, Gao Min, Guo Jingjing, Hu Jia, Lao Lishi, Na Li, Li Ting, Wu Minxia, Peng Bo, Xue Sang, Tian Liang, Hailiang Xiao, Ni Xiong and Yang Jinghui
- Italy: Klaus Dibiasi, Franco "Giorgio" Cagnotto
- Malaysia: Yeoh Ken Nee, Bryan Nickson
- Mexico: Rommel Pacheco and Fernando Platas
- Russia: Alexander Dobroskok, Vera Ilina, Igor Lukashin, Ioulia Pakhalina, and Dmitri Sautin
- Switzerland: Jacqueline Schneider, Catherine Maliev-Aviolat
- United Kingdom: Leon Taylor and Peter Waterfield
- United States: Hobie Billingsley, Bruce Kimball, Beatrice Kyle, Pat McCormick, Mark Lenzi, Greg Louganis, Aileen Riggin, Laura Wilkinson, Jennifer Chandler, Adam Kaplan, Bob Webster, and Scott Donie, Troy Dumais, Bailey Richardson
[edit] All-America College Divers
Bill Ferry (University of Tennessee) - first All-America diver for the Volunteers, six-time SEC individual Champion (1968-1972). First diver in University of Tennessee history to finish four year career and remain undefeated. High school All-America and state champion from Moline, Illinois.
[edit] Non-competitive Diving
Diving is also popular as a non-competitive activity that is often simply done for pleasure or thrills. Such diving usually emphasizes the airborne experience, and the height of the dive, but does not emphasize what goes on once the diver enters the water. The ability to dive underwater can be a useful emergency skill, and is an important part of watersport and navy safety training. More generally, entering water from a height is an enjoyable leisure activity, as is underwater swimming.
