Swimming (sport)
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| Swiming |
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| Swiming |
History
Competitive swimming in Europe began around 1800, mostly in the form of the freestyle. In 1873, Steve Bowyer introduced the trudgen to Western swimming competitions, after copying the front crawl used by Native Americans. Due to a British disregard for splashing, trudgen employed a scissor kick instead of the front crawl’s flutter kick. Swimming was part of the first modern Olympic games in Athens in 1896. In 1902, Richard Cavill introduced the front crawl to the Western world. In 1908, the Fédération Internationale de Natation (FINA), which is the current governing body of the swimming world, was formed. The butterfly stroke was developed in the 1930s and was at first a breaststroke variant, until it was accepted as a separate style in 1952.
In 1912, Fanny Durack (of Australia) became the first female to win an Olympic gold medal, for the 100-meter freestyle.
Physics of swimming
The basic principle of swimming is buoyancy. The human body has a high water content and its density is close to the density of water. Due to its cavities (most prominently the lungs), the average density of the human body is lower than that of water, so it naturally floats. Terry Laughlin has summarized the relevant physical principles for effective and efficient swimming in his book Total Immersion[1] in 1996.
There are two ways to swim faster:
increase power
reduce water resistance
Because the power needed to overcome resistance increases with the third power of the velocity, the first option is not really effective. To increase velocity by 10%, one would need to increase the power by more than 30%.
Laughlin gives three physical principles to reduce drag in swimming:
Balance: how to have a horizontal water position
Due to the lungs, the center of buoyancy and the center of gravity of the human body are not the same. Therefore the lower body has a tendency to sink. If the body is not horizontal but even slightly inclined, the area it offers to drag is much higher, leading to higher resistance. An easy way to stay horizontal is to lean forward and position the head straight in the extension of the spine. In this position the eyes are directed straight downward and the head is more immersed (therefore total immersion).
At the water surface, resistance is proportional to the breadth of a boat. Lying flat on the chest in freestyle or on the back in backstroke exposes the breadth of the body to the water. Rolling on the side reduces the breadth and the resistance. In freestyle and backstroke, one should roll from one side to the other in the stroke and glide on the side as much as possible. When taking breaths, one should take them as little as possible; for beginners it is good to breathe every three strokes and the more trained you are the more strokes in between each breath.
Extended arm
Sailboats are categorized according to boat length. This is due to the wave resistance at the surface. According to Froude, a naval architect in the 19th century, a body moving at the surface of the water creates a wave. The length of the wave depends on the speed. The faster the boat, the longer the wave. Froude found that resistance goes up dramatically when the wave length reaches the length of the boat. There is a simple formula connecting wave velocity to wave length (dispersion equation, metric):
Here c is the velocity of the wave in m/s, g is the gravitational acceleration (9.81 m/s2), and l is the wave length in m. If the maximum swimming speed of c=2.1 m/s is entered, one gets a length of l=2.82 m. This is about the length of a 2 m swimmer with extended arms. So the longer you can glide with the extended arm the less wave resistance. This is also called front quadrant swimming.
Competition
Competitive swimming became popular in the nineteenth century. The goal of competitive swimming is to constantly improve upon one’s time(s), or to beat the competitors in any given event. However, some professional swimmers who do not hold a national or world ranking are considered the best in regard to their technical skills. Typically, an athlete goes through a cycle of training in which the body is overloaded with work in the beginning and middle segments of the cycle, and then the workload is decreased in the final stage as the swimmer approaches the competition in which he or she is to compete in. This final stage is often referred to as “shave and taper”; the swimmer has tapered down his or her workload to be able to perform at their optimal level. At the very end of this stage, before competition, the swimmer shaves off all exposed hair for the sake of reducing drag and having a sleeker and more hydrodynamic feel in the water.[2]
Swimming is an event at the Summer Olympic Games, where male and female athletes compete in 16 of the recognized events each. Olympic events are held in a 50-meter pool, called a long course pool.
There are forty officially recognized individual swimming events in the pool; however the International Olympic Committee only recognizes 32 of them. The international governing body for competitive swimming is the Fédération Internationale de Natation (“International Swimming Federation”), better known as FINA.
Open water
In open water swimming, where the events are swum in a body of open water (lake or sea), there are also 5 km, 10 km and 25 km events for men and women. However, only the 10 km event is included in the Olympic schedule, again for both men and women. Open-water competitions are typically separate to other swimming competitions with the exception of the World Championships and the Olympics.
Swim styles
In competitive swimming, four major styles have been established. These have been relatively stable over the last 30–40 years with minor improvements. The four main strokes in swimming are:
Freestyle
Breaststroke
Backstroke
Butterfly
Dolphin kick
In the past two decades, the most drastic change in swimming has been the addition of the underwater dolphin kick. This is used to maximize the speed at the start and after the turns. The first successful use of it was by David Berkoff at the 1988 Olympics, where he swam most of the 100 m backstroke race underwater and broke the world record on the distance during the preliminaries. Another swimmer to use the technique was Denis Pankratov at the 1996 Olympics in Atlanta, where he completed almost half of the 100 m butterfly underwater to win the gold medal. In the past few years,[when?] American competitive swimmers have shown the most use of the underwater dolphin kick to gain advantage, most notably Olympic and World medal winners Michael Phelps and Ryan Lochte.
While the dolphin kick is mostly seen in middle-distance freestyle events and in all distances of backstroke and butterfly, it is not usually used to the same effect in freestyle sprinting. That changed with the addition of the so-called sharkskin suits until the European Short Course Championships in Rijeka, Croatia in December 2008. There, Amaury Leveaux set new world records of 44.94 seconds in the 100 m freestyle, 20.48 seconds in the 50 m freestyle and 22.18 in the 50 m butterfly. Unlike the rest of the competitors in these events, he spent at least half of each race underwater using the dolphin kick.
While underwater dolphin kicking is allowed in freestyle, backstroke and butterfly, its use is not permitted in the same way in the breaststroke. In 2005, a new rule was formed stating that an optional downward dolphin kick may be used off the start and each turn, and it must occur during the breaststroke pullout. Any other dolphin kick will result in disqualification.
New rules were established to curtail excessive use of underwater dolphin kicks in freestyle, backstroke and butterfly. Currently, performing the dolphin kick past 15 meters results in a disqualification.
Competition pools
Most swimming sport events are held in special competition swimming pools, which are either long course pools such as those used in the Olympic Games (50 m) or short course pools such as those used in the FINA World Swimming Championships (25 yards or 25 m). Competition pools have starting blocks from which the competitor can dive in, and possibly also touch-sensitive pads to electronically record the swimming time of each competitor.
Seasons
Club swimming in the US has two major seasons. During the short-course season, swimmers swim in 25-yard pools. This season lasts from September to the end of March. The long-course season is swum in 50-meter Olympic pools and lasts from April to the end of August.
The longer freestyle events are actually different lengths in each season. In the short course season, the 500 yard, 1000 yard, and 1650-yard freestyle events are swum, while during the long course season the 400 meter, 800 meter, and 1500-meter freestyle events are swum instead. However, this difference in distance holds true for all meter pools, i.e. short course meter pools also swim the 400 meter, 800 meter, and 1500 meter freestyle events instead of their yard counterparts.
Officials
There are several types of officials,[4] which are needed to manage the competition.
Referee: The referee has full control and authority over all officials. The referee will enforce all rules and decisions of FINA and shall decide all questions relating to the actual conduct of the meet, and event or the competition, the final settlement of which is not otherwise covered by the rules. The referee takes overall responsibility for running the race and makes the final decisions as to who wins the competition. Referees call swimmers to the blocks with short blasts of his or her whistle. This is the signal for the swimmers to stand next to their blocks. Starters call missing swimmers if necessary. Then the referee will blow a long whistle that will tell the swimmers to step on a block. The referee will then hand over control to the starter.
Starter: The starter has full control of the swimmers from the time the referee turns the swimmers over to him or /her until the race commences. A starter sends the swimmers off the blocks and may call a false start if a swimmer leaves the block before the starter sends them.
Clerk of course: The clerk of course assembles swimmers prior to each event, and is responsible for organizing (“seeding”) swimmers into heats based on their times. Heats are generally seeded from slowest to fastest, where swimmers with no previous time for an event are assumed to be the slowest.
Timekeepers: There are three timekeepers for each lane. Each timekeeper takes the time of the swimmers in the lane assigned to him/her. Unless a video backup system is used, it may be necessary to use the full complement of timekeepers even when automatic officiating equipment is used. A chief timekeeper assigns the seating positions for all timekeepers and the lanes for which they are responsible. The chief timekeeper collects from the timekeepers in each lane a card showing the times recorded and, if necessary, inspect their watches. One timer will be timing with a stopwatch, another recording it down, and one making sure everything is valid.
Inspectors of turns: One inspector of turns is assigned to each lane at each end of the pool. Each inspector of turns ensures that swimmers comply with the relevant rules for turning as well as the relevant rules for start and finish of the race. Inspectors of turns shall report any violation on disqualification reports detailing the event, lane number, and the infringement delivered to the chief inspector of turns who will immediately convey the report to the referee.
Judges of Stroke: Judges of stroke are located on each side of the pool. They ensure that the rules related to the style of swimming designated for the event are being observed, and observe the turns and the finishes to assist the inspectors of turns.
Finish judges Finish judges determine the order of finish and make sure the swimmers finish in accordance with the rules (two hands simultaneously for breaststroke and butterfly, on the back for backstroke, etc.)
If an official catches a swimmer breaking a rule concerning the stroke he or she is swimming, that swimmer is said to be disqualified (commonly referred to as a “DQ”) and the swim is not considered valid. The referee can disqualify any swimmer for any violation of the rules that he personally observes. The referee may also disqualify any swimmer for any violation reported to him by other authorised officials. All disqualifications are subject to the decision of the referee.
Meet setup
A meet consists of a number of events classified by age, gender, distance, and stroke. For example, Event 1: Girls’ 13–14 100m fly. Each event has a certain number of heats. A heat is a group of people who swim at the same time, one person per lane, yet compete against all entries in that event. Most meets do one stroke at one time. A heat sheet tells a swimmer what they will swim and in what heat and lane. A psych sheet tells the entry position of the swimmer before the start of the meet. Larger meets, which are not national or international competitions, typically cover a three-day period, usually Friday, Saturday, and Sunday. Fridays are typically the longer events: 800 m free, 1500 m free, and the 400 IM. Saturdays consist half of the events and, most likely, free relays. Sundays consist of the remainder of the events and the other relays. In typical meets, swimmers are placed after swimming once in their heat, timed finals. In championship meets (international, national, state, regionals, district, and collegiate) and some other meets, the swimmers compete in preliminaries, sometimes semi-finals, and are placed after finals. Sometimes swimmers can enter time trials at a meet, to obtain new official times, but the results of time trials are not included in the official placing of the particular event at the meet.
Swimwear
Swimsuit
The suit covers the skin for modesty. Competitive swimwear seeks to improve upon bare human skin for a speed advantage. For extra speed, a swimmer wears a body suit, which has rubber or plastic bumps that break up the water close to the body and provides a small amount of thrust—just barely enough to help a swimmer swim faster. However, competitive swimming limits the type of suit a swimmer can wear.
Swim cap
A swim cap (a.k.a. cap) keeps the swimmer’s hair out of the way to reduce drag. Caps may be made of latex, silicone or spandex.
Goggles
Goggles keep water and chlorine out of swimmers’ eyes. Goggles may be tinted to counteract glare at outdoor pools. Prescription goggles may be used by swimmers who wear corrective lenses.
Swimfins
Rubber fins are used to help kick faster. They also improve technique by keeping the feet in the proper position while kicking.
Paddles
Swimmers use these plastic devices to build arm and shoulder strength and refine pulling technique. Hand paddles attach to the hand with rubber surgical tubing or another type of elastic material. They come in many different shapes and sizes.
Kickboard
A kickboard is a foam flotation device that swimmers use to support the weight of the upper body while they focus on kicking.
Pull buoy
Generally used at the same time as hand paddles, pull buoys support swimmers’ legs (and keep them from kicking) while they focus on pulling. Pull buoys are made of foam so they float in the water. Swimmers hold them in between the thighs.
Snorkel
A standard snorkel looks like a capital letter J. Swimmers use them to breathe while their mouths and noses are underwater, so that they can focus on keeping their heads in proper position while swimming. Snorkels are generally made out of a combination of plastic and rubber.
Regular practice and competition swimwear
Men
Men’s most used practice swimwear include briefs and jammers. Males generally swim barechested.
There has been much controversy after the Beijing Olympic Games in 2008, when many Olympic swimmers broke records an unprecedented number of times using revolutionary swimsuits. To highlight the issue, note that it is rare to break world records, but in 2008, 70 world records were broken in one year, and 66 Olympic records were broken in one Olympic Games (there were races in Beijing where the first five finishers were swimming faster than the old world record). Despite many of his records having been won in these suits, Michael Phelps stated that he might boycott the competition after his record was beaten by another swimmer with a more advanced suit.
As of New Year’s Day 2010, men are only allowed to wear suits from the waist to above the knees.[6] They are also only permitted to wear one piece of swimwear; they cannot wear speedos underneath jammers. This rule was enacted after the controversy in the Beijing Olympics and Rome World Championships.
Open-water swimming
Open water swimming is swimming outside of a regular pool, usually in a lake, or sometimes ocean. Popularity of the sport has grown in recent years, particularly since the 10km open water event was added as an Olympic event in 2005, contested for the first time in the 2008 Olympic Games in Beijing.
New recent technology has developed much faster swimsuits. Full body suits have been banned, but swimmers at the very top levels still wear suits that have been lasered together because stitching creates drag. The downfall of these suits: they are sometimes uncomfortable and tight.
Changes to the sport
Swimming times have dropped over the years due to better training techniques and to new developments.
The first four Olympics competitions were not held in pools, but in open water (1896 – The Mediterranean, 1900 – The Seine River, 1904 – an artificial lake, 1906 – The Mediterranean). The 1904 Olympics’ freestyle race was the only one ever measured at 100 yards, instead of the usual 100 meters. A 100-meter pool was built for the 1908 Olympics and sat in the center of the main stadium’s track and field oval. The 1912 Olympics, held in the Stockholm harbor, marked the beginning of electronic timing.
Male swimmers wore full-body suits until the 1940s, which caused more drag in the water than their modern swimwear counterparts did. Competition suits now include engineered fabric and designs to reduce swimmers’ drag in the water and prevent athlete fatigue. In addition, over the years, pool designs have lessened the drag. Some design considerations allow for the reduction of swimming resistance, making the pool faster. Namely, proper pool depth, elimination of currents, increased lane width, energy absorbing racing lane lines and gutters, and the use of other innovative hydraulic, acoustic, and illumination designs.
The 1924 Summer Olympics were the first to use the standard 50-meter pool with marked lanes. In the freestyle, swimmers originally dove from the pool walls, but diving blocks were incorporated at the 1936 Summer Olympics. The flip turn was developed by the 1950s and goggles were first used in the 1976 Olympics.
There were also changes in the late 20th century in terms of technique. Breaststrokers are now allowed to dip their heads completely under water, which allows for a longer stroke and faster time. However, the breaststrokers must bring their heads up at the completion of each cycle. In addition, a split stroke in the breaststroke start and turns has been added to help speed up the stroke. There have been some other changes added recently[when?] as well. Now off the start and turns, breaststrokers are allowed one butterfly kick to help increase their speed. Backstrokers are now allowed to turn on their stomachs before the wall in order to perform a “flip-turn”. Previously, they had to reach and flip backwards and a variation of it, known as a “bucket turn” or a “suicide turn”, is sometimes used in individual medley events to transition from backstroke to breaststroke.
Records
The foundation of FINA in 1908 signalled the commencement of recording the first official world records in swimming.[7] At that time records could be established in any swimming pool of length not less than 25 yards, and records were also accepted for intermediate distance split times from longer distance events. Today World Records will only be accepted when times are reported by Automatic Officiating Equipment, or Semi-Automatic Officiating Equipment in the case of Automatic Officiating Equipment system malfunction.
Records in events such as 300 yd, 300 m, 1000 yd, and 1000 m freestyle, 400 m backstroke, and 400 m and 500 m breaststroke were no longer ratified from 1948. A further removal of the 500 yd and 500 m freestyle, 150 m backstroke, and 3×100 m medley relay from the record listings occurred in 1952.
In 1952, the national federations of the United States and Japan proposed at the FINA Congress the separation of records achieved in long-course and short-course pools, however it was four more years before action to came into effect with Congress deciding to retain only records held in 50 m pools as the official world record listings.
By 1969 there were thirty-one events in which FINA recognised official world records – 16 for men, 15 for women – closely resembling the event schedule that was in use at the Olympic Games.
The increase in accuracy and reliability of electronic timing equipment led to the introduction of hundredths of a second to the time records from 21 August 1972.
Records in short course (25 m) pools began to be officially approved as “short course world records” from 3 March 1991. Prior to this date, times in short course (25 m) pools were not officially recognised, but were regarded a “world best time” (WBT). From 31 October 1994 times in 50 m backstroke, breaststroke, and butterfly were added to the official record listings.
FINA currently recognises world records in the following events for both men and women.
Freestyle: 50 m, 100 m, 200 m, 400 m, 800 m, 1500 m
Backstroke: 50 m, 100 m, 200 m
Breaststroke: 50 m, 100 m, 200 m
Butterfly: 50 m, 100 m, 200 m
Individual medley: 100 m (short course only), 200 m, 400 m
Relays: 4×100 m freestyle, 4×200 m freestyle, 4×100 m medley
Health and skin care
It is recommended[by whom?] that swimmers wear waterproof sunscreen to meets and daytime swim practices that are outside to prevent sunburns. It is also recommended that swimmers dry off well between events at meets and change into dry clothes as soon as possible after swimming to prevent rashes and skin infections.
It also is important for pool water to be properly maintained to avoid rashes and skin infections.
Swimmers should shower with mild soap after swimming to remove pool chemicals such as chlorine and salt. Swimmers should use goggles to protect the eyes from pool water and improve underwater vision.
T he images in action of swiming are:
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