Swimming is the self-

propulsion Propulsion is the generation of force by any combination of pushing or pulling to modify the translational motion of an object, which is typically a rigid body (or an articulated rigid body) but may also concern a fluid. The term is derived f ...

of a person through

water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...

, or other liquid, usually for recreation, sport, exercise, or survival. Locomotion is achieved through coordinated movement of the limbs and the body to achieve hydrodynamic thrust that results in directional motion. Humans can hold their breath underwater and undertake rudimentary locomotive swimming within weeks of birth, as a survival response. Swimming is consistently among the top public recreational activities, and in some countries,

swimming lessons Swimming lessons are the process of learning to swim. In most countries there is a definition of a number of swimming levels that are reached in the process of the curriculum. The respective certificates of swimming tests are required for furt ...

are a compulsory part of the educational curriculum. As a formalized sport, swimming is featured in a range of local, national, and international competitions, including every modern Summer Olympics. Swimming involves repeated motions known as

strokes A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop funct ...

in order to propel the body forward. While the

front crawl The front crawl or forward crawl, also known as the Australian crawl or American crawl, is a swimming stroke usually regarded as the fastest of the four front primary strokes. As such, the front crawl stroke is almost universally used during a f ...

, also known as freestyle, is widely regarded as the fastest out of four primary strokes, other strokes are practiced for special purposes, such as for training. There are various risks present during swimming, mainly due to it taking place in water. Swimmers are at risk of incapacitation due to

panic Panic is a sudden sensation of fear, which is so strong as to dominate or prevent reason and logical thinking, replacing it with overwhelming feelings of anxiety and frantic agitation consistent with an animalistic fight-or-flight reactio ...

and

exhaustion Fatigue describes a state of tiredness that does not resolve with rest or sleep. In general usage, fatigue is synonymous with extreme tiredness or exhaustion that normally follows prolonged physical or mental activity. When it does not resolve ...

, which may cause death due to

drowning Drowning is a type of suffocation induced by the submersion of the mouth and nose in a liquid. Most instances of fatal drowning occur alone or in situations where others present are either unaware of the victim's situation or unable to offer as ...

. Other dangers include getting an

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dis ...

or contact with hostile aquatic fauna. To minimize these risks, most facilities employ a lifeguard to look for signs of distress. Swimmers often wear specialized swimwear, although depending on the culture of the area, some swimmers may also swim nude or wear their day attire. In addition to this, a variety of equipment can be used to enhance the swimming experience or performance, including but not limited to the use of

swimming goggles Goggles, or safety glasses, are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and i ...

floatation device A personal flotation device (PFD; also referred to as a life jacket, life preserver, life belt, Mae West, life vest, life saver, cork jacket, buoyancy aid or flotation suit) is a flotation device in the form of a vest or suite that is worn by a ...

swim fins Swimfins, swim fins, diving fins, or flippers are finlike accessories worn on the feet, legs or hands and made from rubber, plastic, carbon fiber or combinations of these materials, to aid movement through the water in water sports activities s ...

, and snorkels.

Science

Swimming relies on the nearly

neutral buoyancy Neutral buoyancy occurs when an object's average density is equal to the density of the fluid in which it is immersed, resulting in the buoyant force balancing the force of gravity that would otherwise cause the object to sink (if the body's densi ...

of the human body. On average, the body has a relative density of 0.98 compared to water, which causes the body to float. However, buoyancy varies on the basis of body composition, lung inflation, muscle and fat content, centre of gravity and the salinity of the water. Higher levels of body fat and saltier water both lower the relative density of the body and increase its buoyancy. Human males tend to have a lower centre of gravity and higher muscle content, therefore find it more difficult to float or be buoyant. See also: ''

Hydrostatic weighing Hydrostatic weighing, also referred to as underwater weighing, hydrostatic body composition analysis and hydrodensitometry, is a technique for measuring the density of a living person's body. It is a direct application of Archimedes' principle, t ...

.'' Since the human body is less dense than water, water is able to support the weight of the body during swimming. As a result, swimming is “low-impact” compared to land activities such as running. The density and

viscosity The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the inte ...

of water also create resistance for objects moving through the water. Swimming strokes use this resistance to create propulsion, but this same resistance also generates drag on the body. Hydrodynamics is important to stroke technique for swimming faster, and swimmers who want to swim faster or exhaust less try to reduce the drag of the body's motion through the water. To be more hydrodynamically effective, swimmers can either increase the power of their strokes or reduce water resistance, though power must increase by a factor of three to achieve the same effect as reducing resistance. Efficient swimming by reducing water resistance involves a horizontal water position, rolling the body to reduce the breadth of the body in the water, and extending the arms as far as possible to reduce wave resistance. Just before plunging into the pool, swimmers may perform exercises such as squatting. Squatting helps in enhancing a swimmer's start by warming up the thigh muscles.

Infant swimming

Human babies demonstrate an innate swimming or

diving reflex The diving reflex, also known as the diving response and mammalian diving reflex, is a set of physiological responses to immersion that overrides the basic homeostatic reflexes, and is found in all air-breathing vertebrates studied to date. It o ...

from newborn until the age of approximately 6 months. Other mammals also demonstrate this phenomenon (see

mammalian diving reflex The diving reflex, also known as the diving response and mammalian diving reflex, is a set of physiological responses to immersion that overrides the basic homeostatic reflexes, and is found in all air-breathing vertebrates studied to date. It o ...

). The diving response involves apnea,

reflex bradycardia Reflex bradycardia is a bradycardia (decrease in heart rate) in response to the baroreceptor reflex, one of the body's homeostatic mechanisms for preventing abnormal increases in blood pressure. In the presence of high mean arterial pressure, t ...

, and peripheral

vasoconstriction Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vess ...

; in other words, babies immersed in water spontaneously hold their breath, slow their heart rate, and reduce blood circulation to the extremities (fingers and toes). Because infants are innately able to swim, classes for babies of about 6 months old are offered in many locations. This helps build muscle memory and makes strong swimmers from a young age.

Technique

Swimming can be undertaken using a wide range of styles, known as 'strokes,' and these strokes are used for different purposes, or to distinguish between classes in competitive swimming. It is not necessary to use a defined stroke for propulsion through the water, and untrained swimmers may use a '

doggy paddle The dog paddle or doggy paddle is a simple swimming style. It is characterized by the swimmer lying on their chest and moving their hands and legs alternately in a manner reminiscent of how dogs and other quadrupedal mammals swim. It is effectiv ...

' of arm and leg movements, similar to the way four-legged animals swim. There are four main strokes used in competition and recreation swimming: the

, also known as freestyle, breaststroke,

backstroke Backstroke or back crawl is one of the four swimming styles used in competitive events regulated by FINA, and the only one of these styles swum on the back. This swimming style has the advantage of easy breathing, but the disadvantage of swimm ...

and

butterfly Butterflies are insects in the macrolepidopteran clade Rhopalocera from the order Lepidoptera, which also includes moths. Adult butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. The group comprise ...

. Competitive swimming in Europe started around 1800, mostly using the breaststroke. In 1873, John Arthur Trudgen introduced the

trudgen The trudgen is a swimming stroke sometimes known as the ''racing stroke'', or the ''East Indian stroke''. It is named after the English swimmer John Trudgen (1852–1902) and evolved out of sidestroke. One swims mostly upon one side, making an o ...

to Western swimming competitions. Butterfly was developed in the 1930s, and was considered a variant of the breaststroke until accepted as a separate style in 1953. Butterfly is considered the hardest stroke by many people, but it is the most effective for all-around toning and the building of muscles. It also burns the most calories and can be the second fastest stroke if practiced regularly. In non-competitive swimming, there are some swimming strokes including

sidestroke The sidestroke is a swimming stroke, so named because the swimmer lies on one's side with asymmetric arm and leg motion. It is helpful as a lifesaving technique and is often used for long-distance swimming. The sidestroke allows the swimmer increa ...

. The sidestroke toward the end of the 19th century, this pattern was changed by raising one arm above the water first, then the other, and then each in turn. It is still used in lifesaving and recreational swimming. Other strokes exist for particular reasons such as training, school lessons, and rescue, and it is often possible to change strokes to avoid using parts of the body, either to separate specific body parts, such as swimming with only arms or legs to exercise them harder, or for amputees or those affected by paralysis.

History

Swimming has been recorded since prehistoric times, and the earliest records of swimming date back to Stone Age

paintings Painting is the practice of applying paint, pigment, color or other medium to a solid surface (called the "matrix" or "support"). The medium is commonly applied to the base with a brush, but other implements, such as knives, sponges, and ai ...

from around 7,000 years ago. Written references date from 2000 BC. Some of the earliest references include the

Epic of Gilgamesh The ''Epic of Gilgamesh'' () is an epic poem from ancient Mesopotamia, and is regarded as the earliest surviving notable literature and the second oldest religious text, after the Pyramid Texts. The literary history of Gilgamesh begins with ...

, the

Iliad The ''Iliad'' (; grc, Ἰλιάς, Iliás, ; "a poem about Ilium") is one of two major ancient Greek epic poems attributed to Homer. It is one of the oldest extant works of literature still widely read by modern audiences. As with the '' Odys ...

, the

Odyssey The ''Odyssey'' (; grc, Ὀδύσσεια, Odýsseia, ) is one of two major ancient Greek epic poems attributed to Homer. It is one of the oldest extant works of literature still widely read by modern audiences. As with the ''Iliad'', th ...

, the

Bible The Bible (from Koine Greek , , 'the books') is a collection of religious texts or scriptures that are held to be sacred in Christianity, Judaism, Samaritanism, and many other religions. The Bible is an anthologya compilation of texts ...

(Ezekiel 47:5, Acts 27:42, Isaiah 25:11), Beowulf, and other sagas. The coastal tribes living in the volatile

Low Countries The term Low Countries, also known as the Low Lands ( nl, de Lage Landen, french: les Pays-Bas, lb, déi Niddereg Lännereien) and historically called the Netherlands ( nl, de Nederlanden), Flanders, or Belgica, is a coastal lowland region in N ...

were known as excellent swimmers by the

Romans Roman or Romans most often refers to: *Rome, the capital city of Italy * Ancient Rome, Roman civilization from 8th century BC to 5th century AD *Roman people, the people of ancient Rome *''Epistle to the Romans'', shortened to ''Romans'', a lette ...

. Men and horses of the Batavi tribe could cross the

Rhine ), Surselva, Graubünden, Switzerland , source1_coordinates= , source1_elevation = , source2 = Rein Posteriur/Hinterrhein , source2_location = Paradies Glacier, Graubünden, Switzerland , source2_coordinates= , so ...

without losing formation, according to

Tacitus Publius Cornelius Tacitus, known simply as Tacitus ( , ; – ), was a Roman historian and politician. Tacitus is widely regarded as one of the greatest Roman historians by modern scholars. The surviving portions of his two major works—the ...

. Dio Cassius describes one surprise tactic employed by

Aulus Plautius Aulus Plautius was a Roman politician and general of the mid-1st century. He began the Roman conquest of Britain in 43, and became the first governor of the new province, serving from 43 to 46 CE. Career Little is known of Aulus Plautius's e ...

against the

Celts The Celts (, see pronunciation for different usages) or Celtic peoples () are. "CELTS location: Greater Europe time period: Second millennium B.C.E. to present ancestry: Celtic a collection of Indo-European peoples. "The Celts, an ancien ...

at the

Battle of the Medway The Battle of the Medway took place in 43 AD, probably on the River Medway in the lands of the Iron Age tribe of the Cantiaci, now the English county of Kent. Other locations for the battle have been suggested but are less likely. This was an ...

The ritish Celtsthought that Romans would not be able to cross it without a bridge, and consequently bivouacked in rather careless fashion on the opposite bank; but he sent across a detachment of atavii who were accustomed to swim easily in full armour across the most turbulent streams. . . . Thence the Britons retired to the river Thames at a point near where it empties into the ocean and at flood-tide forms a lake. This they easily crossed because they knew where the firm ground and the easy passages in this region were to be found, but the Romans in attempting to follow them were not so successful. However, the ataviiswam across again and some others got over by a bridge a little way up-stream, after which they assailed the barbarians from several sides at once and cut down many of them."

In 1538, Nikolaus Wynmann, a Swiss–German professor of languages, wrote the earliest known complete book about swimming, ''Colymbetes, sive de arte natandi dialogus et festivus et iucundus lectu'' (''The Swimmer, or A Dialogue on the Art of Swimming and Joyful and Pleasant to Read'').

Purpose

There are many reasons why people swim, from swimming as a recreational pursuit to swimming as a necessary part of a job or other activity. Swimming may also be used to rehabilitate injuries, especially various cardiovascular and muscle injuries. People may also pursue swimming as a career or field of interest. Some may be gifted and choose to compete professionally and go onto claim fame.

Recreation

Many swimmers swim for recreation, with swimming consistently ranking as one of the physical activities people are most likely to take part in. Recreational swimming can also be used for exercise, relaxation or rehabilitation. The support of the water, and the reduction in impact, makes swimming accessible for people who are unable to undertake activities such as running. Swimming is one of the most relaxing activities, water is known to calm us and can help reduce stress.

Health

Swimming is primarily a cardiovascular/aerobic exercise due to the long exercise time, requiring a constant oxygen supply to the muscles, except for short sprints where the muscles work anaerobically. Furthermore, swimming can help tone and strengthen muscles. Swimming allows sufferers of arthritis to exercise affected joints without worsening their symptoms. However, swimmers with arthritis may wish to avoid swimming breaststroke, as improper technique can exacerbate arthritic knee pain. As with most aerobic exercise, swimming reduces the harmful effects of stress. Swimming is also effective in improving health for people with cardiovascular problems and chronic illnesses. It is proven to positively impact the mental health of pregnant women and mothers. Swimming can even improve mood. Although many forms of physical activity have been shown to improve

bone density Bone density, or bone mineral density, is the amount of bone mineral in bone tissue. The concept is of mass of mineral per volume of bone (relating to density in the physics sense), although clinically it is measured by proxy according to optic ...

and health, this is where swimming has its downfalls. Due to the low-impact nature of the sport, studies have demonstrated that bone mass acquisition will be negatively impacted, which could be an issue for adolescent athletes in particular. Regular swimming activities contribute to the restoration of health, and in many cases, complete recovery. Activity in water is the basis for a good work of the heart muscle, the endocrine system of the body, stable blood pressure, full blood circulation in the vessels, which is not only the prevention of a lot of problems but also a powerful healing effect without any side effects.

Disabled swimmers

Since 2010, the Americans with Disabilities Act has required that swimming pools in the United States be accessible to disabled swimmers.

Elderly swimmers

"Water-based exercise can benefit older adults by improving quality of life and decreasing disability. It also improves or maintains the bone health of post-menopausal women." Swimming is an ideal workout for the elderly, as it is a low-impact sport with very little risk of injury. Exercise in the water works out all muscle groups, helping with conditions such as muscular dystrophy which is common in seniors. It is also a common way to relieve pain from arthritis.

Sport

Swimming as a sport predominantly involves participants competing to be the fastest over a given distance in a certain period of time. Competitors swim different distances in different levels of competition. For example, swimming has been an

Olympic sport Olympic sports are contested in the Summer Olympic Games and Winter Olympic Games. The 2020 Summer Olympics included 33 sports; the 2022 Winter Olympics included seven sports. Each Olympic sport is represented by an international governing ...

since 1896, and the current program includes events from 50 m to 1500 m in length, across all four main strokes and medley. During the season competitive swimmers typically train several times a week, this is in order to preserve fitness as well as promoting overload in training. Furthermore when the cycle of work is completed swimmers go through a stage called taper where intensity is reduced in preparation for racing, during taper power and feel in the water are concentrated. The sport is governed internationally by the Fédération Internationale de Natation (FINA), and competition pools for FINA events are 25 or 50 meters in length. In the United States, a pool 25 yards in length is commonly used for competition. Other swimming and water-related sporting disciplines include

open water swimming Open water swimming is a swimming discipline which takes place in outdoor bodies of water such as open oceans, lakes, and rivers. The beginning of the modern age of open water swimming is sometimes taken to be May 3, 1810, when Lord Byron swam s ...

diving Diving most often refers to: * Diving (sport), the sport of jumping into deep water * Underwater diving, human activity underwater for recreational or occupational purposes Diving or Dive may also refer to: Sports * Dive (American football), a ...

, synchronized swimming,

water polo Water polo is a competitive sport, competitive team sport played in water between two teams of seven players each. The game consists of four quarters in which the teams attempt to score goals by throwing the water polo ball, ball into the oppo ...

triathlon A triathlon is an endurance multisport race consisting of swimming, cycling, and running over various distances. Triathletes compete for fastest overall completion time, racing each segment sequentially with the time transitioning between the ...

, and the modern pentathlon.

Safety

As a popular leisure activity done all over the world, one of the primary risks of swimming is

. Drowning may occur from a variety of factors, from swimming fatigue to simply inexperience in the water. From 2005 to 2014, an average of 3,536 fatal unintentional drownings occurred in the United States, approximating 10 deaths a day. To minimize the risk and prevent potential drownings from occurring, lifeguards are often employed to supervise swimming locations such as pools, waterparks, lakes and beaches. Different lifeguards receive different training depending on the sites that they are employed at; i.e. a waterfront lifeguard receives more rigorous training than a poolside lifeguard. Well-known aquatic training services include th
National Lifesaving Society
and the

Canadian Red Cross The Canadian Red Cross Society ()abalone and

pearl A pearl is a hard, glistening object produced within the soft tissue (specifically the mantle) of a living shelled mollusk or another animal, such as fossil conulariids. Just like the shell of a mollusk, a pearl is composed of calcium carb ...

diving, and

spearfishing Spearfishing is a method of fishing that involves impaling the fish with a straight pointed object such as a spear, gig or harpoon. It has been deployed in artisanal fishing throughout the world for millennia. Early civilisations were familia ...

. Swimming is used to rescue people in the water who are in distress, including exhausted swimmers, non-swimmers who have accidentally entered the water, and others who have come to harm on the water. Lifeguards or volunteer lifesavers are deployed at many pools and beaches worldwide to fulfil this purpose, and they, as well as

rescue swimmer Rescue swimmer is a designation given to rescue specialists, most commonly in the service of the military. Rescue swimmers usually are charged with the rescue, assessment, and rendering of medical aid to persons in distress in the sea, on the land ...

s, may use specific

swimming styles Swimming is the self-propulsion of a person through water, or other liquid, usually for recreation, sport, exercise, or survival. Locomotion is achieved through coordinated movement of the limbs and the body to achieve hydrodynamic thrust that r ...

for rescue purposes. Swimming is also used in marine biology to observe plants and animals in their natural habitat. Other sciences use swimming; for example,

Konrad Lorenz Konrad Zacharias Lorenz (; 7 November 1903 – 27 February 1989) was an Austrian zoologist, ethologist, and ornithologist. He shared the 1973 Nobel Prize in Physiology or Medicine with Nikolaas Tinbergen and Karl von Frisch. He is often regarde ...

swam with geese as part of his studies of

animal behavior Ethology is the scientific study of animal behaviour, usually with a focus on behaviour under natural conditions, and viewing behaviour as an evolutionarily adaptive trait. Behaviourism as a term also describes the scientific and objectiv ...

. Swimming also has military purposes. Military swimming is usually done by special operation forces, such as

Navy SEALs The United States Navy Sea, Air, and Land (SEAL) Teams, commonly known as Navy SEALs, are the U.S. Navy's primary special operations force and a component of the Naval Special Warfare Command. Among the SEALs' main functions are conducting sm ...

and

US Army Special Forces The United States Army Special Forces (SF), colloquially known as the "Green Berets" due to their distinctive service headgear, are a special operations force of the United States Army. The Green Berets are geared towards nine doctrinal mis ...

. Swimming is used to approach a location, gather intelligence, engage in sabotage or combat, and subsequently depart. This may also include airborne insertion into water or exiting a submarine while it is submerged. Due to regular exposure to large bodies of water, all recruits in the

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

Marine Corps Marines, or naval infantry, are typically a military force trained to operate in littoral zones in support of naval operations. Historically, tasks undertaken by marines have included helping maintain discipline and order aboard the ship (refl ...

, and

Coast Guard A coast guard or coastguard is a maritime security organization of a particular country. The term embraces wide range of responsibilities in different countries, from being a heavily armed military force with customs and security duties to ...

are required to complete basic swimming or water survival training. Swimming is also a professional sport. Companies sponsor swimmers who have the skills to compete at the international level. Many swimmers compete competitively to represent their home countries in the Olympics. Professional swimmers may also earn a living as entertainers, performing in water ballets.

Locomotion

Locomotion by swimming over brief distances is frequent when alternatives are precluded. There have been cases of political refugees swimming in the Baltic Sea and of people jumping in the water and swimming ashore from vessels not intended to reach land where they planned to go.

Risks

There are many risks associated with voluntary or involuntary human presence in water, which may result in death directly or through drowning asphyxiation. Swimming is both the goal of much voluntary presence and the prime means of regaining land in accidental situations. Most recorded water deaths fall into these categories: *

Panic Panic is a sudden sensation of fear, which is so strong as to dominate or prevent reason and logical thinking, replacing it with overwhelming feelings of anxiety and frantic agitation consistent with an animalistic fight-or-flight reactio ...

occurs when an inexperienced swimmer or a nonswimmer becomes mentally overwhelmed by the circumstances of their immersion, leading to sinking and drowning. Occasionally, panic kills through hyperventilation, even in shallow water. *

Exhaustion Fatigue describes a state of tiredness that does not resolve with rest or sleep. In general usage, fatigue is synonymous with extreme tiredness or exhaustion that normally follows prolonged physical or mental activity. When it does not resolve ...

can make a person unable to sustain efforts to swim or tread water, often leading to death through drowning. An adult with fully developed and extended lungs has generally positive or at least neutral

buoyancy Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the ...

, and can float with modest effort when calm and in still water. A small child has negative buoyancy and must make a sustained effort to avoid sinking rapidly. *

Hypothermia Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe ...

, in which a person loses critical core temperature, can lead to unconsciousness or heart failure. *

Dehydration In physiology, dehydration is a lack of total body water, with an accompanying disruption of metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental temperature. Mil ...

from prolonged exposure to

hypertonic In chemical biology, tonicity is a measure of the effective osmotic pressure gradient; the water potential of two solutions separated by a partially-permeable cell membrane. Tonicity depends on the relative concentration of selective membrane- ...

salt water—or, less frequently, salt water aspiration syndrome where inhaled salt water creates foam in the lungs that restricts breathing—can cause loss of physical control or kill directly without actual drowning. Hypothermia and dehydration also kill directly, without causing drowning, even when the person wears a

life vest A personal flotation device (PFD; also referred to as a life jacket, life preserver, life belt, Mae West, life vest, life saver, cork jacket, buoyancy aid or flotation suit) is a flotation device in the form of a vest or suite that is worn by a ...

. * Blunt trauma in a fast moving flood or river water can kill a swimmer outright, or lead to their drowning. Adverse effects of swimming can include: *

Exostosis An exostosis, also known as bone spur, is the formation of new bone on the surface of a bone. Exostoses can cause chronic pain ranging from mild to debilitatingly severe, depending on the shape, size, and location of the lesion. It is most commonl ...

, an abnormal bony overgrowth narrowing the ear canal due to frequent, long-term splashing or filling of cold water into the ear canal, also known as

surfer's ear Surfer's ear is the common name for an exostosis or abnormal bone growth within the ear canal. Surfer's ear is not the same as swimmer's ear, although infection can result as a side effect. Irritation from cold wind and water exposure causes th ...

* Infection from water-borne bacteria, viruses, or parasites * Chlorine inhalation (in swimming pools) * Heart attacks while swimming (the primary cause of sudden death among

participants, occurring at the rate of 1 to 2 per 100,000 participations.) * Adverse encounters with aquatic life: ** Stings from

sea lice Sea lice (singular: sea louse) are copepods (small crustaceans) of the family Caligidae within the order Siphonostomatoida. They are marine ectoparasites (external parasites) that feed on the mucus, epidermal tissue, and blood of host fish. The ...

, jellyfish, fish, seashells, and some species of

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and ...

** Puncture wounds caused by crabs, lobsters, sea urchins,

zebra mussel The zebra mussel (''Dreissena polymorpha'') is a small freshwater mussel. The species originates from the lakes of southern Russia and Ukraine, but has been accidentally introduced to numerous other areas and has become an invasive species in ma ...

stingrays Stingrays are a group of sea rays, which are cartilaginous fish related to sharks. They are classified in the suborder Myliobatoidei of the order Myliobatiformes and consist of eight families: Hexatrygonidae (sixgill stingray), Plesiobatidae ...

flying fish The Exocoetidae are a family of marine fish in the order Beloniformes class Actinopterygii, known colloquially as flying fish or flying cod. About 64 species are grouped in seven to nine genera. While they cannot fly in the same way a bird d ...

, sea birds, and debris ** Hemorrhaging bites from fish, marine mammals, and marine reptiles, occasionally resulting from

predation Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

** Venomous bites from

sea snake Sea snakes, or coral reef snakes, are elapid snakes that inhabit marine environments for most or all of their lives. They belong to two subfamilies, Hydrophiinae and Laticaudinae. Hydrophiinae also includes Australasian terrestrial snakes, wher ...

s and certain species of octopus ** Electrocution or mild shock from electric eels and electric rays Around any pool area, safety equipment is often important, and is a zoning requirement for most residential pools in the United States. Supervision by personnel trained in rescue techniques is required at most competitive swimming meets and public pools.

Lessons

Traditionally, children were considered not able to swim independently until 4 years of age, although now

infant swimming Infant swimming is the phenomenon of human babies and toddlers reflexively moving themselves through water and changing their rate of respiration and heart rate in response to being submerged. The slowing of heart rate and breathing is called the ...

lessons are recommended to prevent drowning. In Sweden, Denmark, Norway,

Estonia Estonia, formally the Republic of Estonia, is a country by the Baltic Sea in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the sea across from Sweden, to the south by Latvia, a ...

and Finland, the

curriculum In education, a curriculum (; : curricula or curriculums) is broadly defined as the totality of student experiences that occur in the educational process. The term often refers specifically to a planned sequence of instruction, or to a view ...

for the fifth grade (fourth grade in Estonia) states that all children should learn how to swim as well as how to handle emergencies near water. Most commonly, children are expected to be able to swim —of which at least on their back – after first falling into deep water and getting their head under water. Even though about 95 percent of Swedish school children know how to swim, drowning remains the third most common cause of death among children. In both the Netherlands and Belgium swimming lessons under school time (''schoolzwemmen'', school swimming) are supported by the government. Most schools provide swimming lessons. There is a long tradition of swimming lessons in the Netherlands and Belgium, the Dutch translation for the breaststroke swimming style is even ''schoolslag'' (schoolstroke). In France, swimming is a compulsory part of the curriculum for primary schools. Children usually spend one semester per year learning swimming during CP/CE1/CE2/CM1 (1st, 2nd, 3rd and 4th grade). In many places, swimming lessons are provided by local swimming pools, both those run by the local authority and by private leisure companies. Many schools also include swimming lessons into their Physical Education

curricula In education, a curriculum (; : curricula or curriculums) is broadly defined as the totality of student experiences that occur in the educational process. The term often refers specifically to a planned sequence of instruction, or to a view ...

, provided either in the schools' own pool or in the nearest public pool. In the UK, the "Top-ups scheme" calls for school children who cannot swim by the age of 11 to receive intensive daily lessons. Children who have not reached Great Britain's National Curriculum standard of swimming 25 meters by the time they leave primary school receive a half-hour lesson every day for two weeks during term-time. In Canada and Mexico there has been a call to include swimming in public school curriculum. In the United States there is the Infant Swimming Resource (ISR) initiative that provides lessons for infant children, to cope with an emergency where they have fallen into the water. They are taught how to roll-back-to-float (hold their breath underwater, to roll onto their back, to float unassisted, rest and breathe until help arrives), while clothed and unclothed. In ISR they teach the children how to roll with their clothes on, as a simulation, if they were to actually fall in walking or crawling by. In Switzerland, swimming lessons for babies are popular, to help them getting used to be in another element. At the competition level, unlike in other countries - such as the Commonwealth countries, swimming teams are not related to educational institutions (high-schools and universities), but rather to cities or regions.

Clothing and equipment

Swimsuits

Standard everyday clothing is usually impractical for swimming and is unsafe under some circumstances. Most cultures today expect swimmers to wear

swimsuits A swimsuit is an item of clothing designed to be worn by people engaging in a water-based activity or water sports, such as swimming, diving and surfing, or sun-orientated activities, such as sun bathing. Different types may be worn by men, wo ...

. Men's swimsuits commonly resemble

shorts Shorts are a garment worn over the pelvic area, circling the waist and splitting to cover the upper part of the legs, sometimes extending down to the knees but not covering the entire length of the leg. They are called "shorts" because they ...

, or

briefs Briefs (or a brief) are a type of short, form-fitting underwear and swimwear, as opposed to styles where material extends down the thighs. Briefs have various different styles, usually with a waistband attached to fabric that runs along the pe ...

. Men's casual swimsuits (for example,

boardshorts Boardshorts are a type of swimwear and casual wear in the form of relatively long (approximately knee length) loose-fitting shorts that are designed to be quick-drying and are generally made from strong and smooth polyester or nylon material. Or ...

) are rarely skintight, unlike

competitive swimwear Competitive swimwear refers to the swimsuit, clothing, equipment, and accessories used in the aquatic sports of swimming, diving, synchronized swimming, triathlon, and water polo. Some swimsuits are designed specifically for swimming competi ...

, like jammers or diveskins. In most cases, boys and men swim with their upper body exposed, except in countries where custom or law prohibits it in a public setting, or for practical reasons such as sun protection. Modern women's swimsuits are generally skintight, covering the pubic region and the

breasts The breast is one of two prominences located on the upper ventral region of a primate's torso. Both females and males develop breasts from the same embryological tissues. In females, it serves as the mammary gland, which produces and sec ...

(See

bikini A bikini is a two-piece swimsuit primarily worn by women that features two triangles of fabric on top that cover the breasts, and two triangles of fabric on the bottom: the front covering the pelvis but exposing the navel, and the back coverin ...

). Women's swimwear may also cover the

midriff In fashion, the midriff is the human abdomen. The midriff is exposed when wearing a crop top or some forms of swimwear or underwear. Cholis worn by Indian women expose a section of midriff, usually . Etymology "Midriff" is a very old term in ...

as well. Women's swimwear is often a fashion statement, and whether it is modest or not is a subject of debate by many groups, religious and secular. Dance With Waves

Competitive swimwear Competitive swimwear refers to the swimsuit, clothing, equipment, and accessories used in the aquatic sports of swimming, diving, synchronized swimming, triathlon, and water polo. Some swimsuits are designed specifically for swimming competi ...

is built so that the wearer can swim faster and more efficiently. Modern competitive swimwear is skintight and lightweight. There are many kinds of competitive swimwear for each gender. It is used in aquatic competitions, such as water polo, swim racing, diving, and

rowing Rowing is the act of propelling a human-powered watercraft using the sweeping motions of oars to displace water and generate reactional propulsion. Rowing is functionally similar to paddling, but rowing requires oars to be mechanically ...

Wetsuits A wetsuit is a garment worn to provide thermal protection while wet. It is usually made of foamed neoprene, and is worn by surfers, divers, windsurfers, canoeists, and others engaged in water sports and other activities in or on water. Its p ...

provide both thermal insulation and flotation. Many swimmers lack buoyancy in the leg. The wetsuit provides additional volume at a lower density and therefore improves buoyancy and trim while swimming. It provides insulation between the skin and water which reduces heat loss. The wetsuit is the usual choice for those who swim in cold water for long periods of time, as it reduces susceptibility to

hypothermia Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe ...

. Some people also choose to wear no clothing while swimming; this is known as skinny dipping. In some European countries public pools have naturist sessions to allow clothes-free swimming and many countries have naturist beaches where one can swim naked. It is legal to swim naked in the sea at all UK beaches. It was common for males to swim naked in a public setting up to the early 20th century. Today, skinny dipping can be a rebellious activity or merely a casual one.

Accessories

Ear plugs An earplug is a device that is inserted in the ear canal to protect the user's ears from loud noises, intrusion of water, foreign bodies, dust or excessive wind. Since they reduce the sound volume, earplugs are often used to help prevent hearing ...

can prevent water from getting in the ears. *

Noseclip A noseclip or nose clip is a device designed to hold the nostrils closed to prevent water from entering, or air from escaping, by people during aquatic activities such as kayaking, freediving, Pelizzari, Umberto & Tovaglieri, Stefano (2001) ''‘ ...

s can prevent water from getting in the nose. However, using noseclips in competitive swimming can cause disadvantage, so many competitive swimmer choose not to use one. For this reason, nose clips are primarily used for synchronized swimming and recreational swimming. *

Goggles Goggles, or safety glasses, are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and ...

protect the eyes from chlorinated water, and improve underwater visibility. Tinted goggles protect the eyes from sunlight that reflects from the bottom of the pool. * Swim caps keep the body streamlined and protect the hair from chlorinated water, though they are not entirely watertight. *

Kickboard A swimming float, commonly known as pool float or floaty, is a device used for toddlers or other very young children who are beginning to learn how to swim, or during exercise for therapeutic or training purposes. These devices, which come in many ...

s are used to keep the upper body afloat while exercising the lower body. *

Pull buoy A pull buoy or leg float is a figure-eight shaped piece of closed-cell foam used in swim workouts. Swimmers place the buoy between their thighs or their ankles to provide support to the body without kicking their legs; this allows the swimmer to ...

s are used to keep the lower body afloat while exercising the upper body. *

Swimfins Swimfins, swim fins, diving fins, or flippers are finlike accessories worn on the feet, legs or hands and made from rubber, plastic, carbon fiber or combinations of these materials, to aid movement through the water in water sports activities s ...

are used in training to elongate the kick and improve technique and speed. Fins also build upper calf muscles. Fins provide a significantly greater and more efficient conversion of muscle power to thrust than available from the feet, and allow the powerful leg muscles to be used effectively for propulsion through water. The value of fins as an active aid in the teaching, learning and practice of swimming has long been recognised. In the US, as early as 1947, they were used experimentally to build the confidence of reluctant beginners in swimming, while a 1950

YMCA YMCA, sometimes regionally called the Y, is a worldwide youth organization based in Geneva, Switzerland, with more than 64 million beneficiaries in 120 countries. It was founded on 6 June 1844 by George Williams (philanthropist), Georg ...

lifesaving and water safety manual reminded swimming instructors how "flippers can be used to great advantage for treading water, surface diving, towing, underwater searching and supporting a tired swimmer". In 1967, research was conducted on fin use in teaching the crawl stroke. During the 1970s, the so-called "flipper-float" method came into vogue in Europe with the aim of helping beginners learn to swim faster and more safely, * Hand paddles are used to increase resistance during arm movements, with the goal of improving technique and power. * Finger paddles have a similar effect to handle paddles however due to their smaller size create less resistance. They also help with improving a swimmers 'catch' in the water. * Snorkels are used to help improve and maintain a good head position in the water. They may also be used by some during physical therapy. *

Pool noodle A pool noodle is a cylindrical piece of flexible, buoyant polyethylene foam. Pool noodles are used by people of all ages while swimming. Pool noodles are useful when learning to Human swimming, swim, for floating, for rescue reaching, in variou ...

s are used to keep the user afloat during the time in the water. * Safety fencing and equipment is mandatory at public pools and a zoning requirement at most residential pools in the United States. * Swimming Parachutes are used in competitive training, adding an element of resistance in the water helping athletes to increase power in the strokes central movements. *

Inflatable armbands Inflatable armbands, usually referred to as simply armbands, water wings, swimmies, or floaties, are swim aids designed to help a wearer float in water and learn to swim. Inflatable armbands are typically cylindrical, inflatable plastic bands ...

are swimming aids designed to provide buoyancy for the swimmer which helps the wearer to float.

References

Bibliography

* * Maniscalco F., Il nuoto nel mondo greco romano, Naples 1993. * Mehl H., Antike Schwimmkunst, Munchen 1927. * Schuster G., Smits W. & Ullal J., ''Thinkers of the Jungle''. Tandem Verlag 2008. * svin *

External links

*
Swimmingstrokes.info
Overview of 150 historical and less known swimming-strokes
Swimming for men's health
{{Authority control

Swimming Swimming is the self-propulsion of a person through water, or other liquid, usually for recreation, sport, exercise, or survival. Locomotion is achieved through coordinated movement of the limbs and the body to achieve hydrodynamic thrust that r ...