Swimfins,
swim fins,
fins or
flippers are worn on the foot or leg and made from
finA fin is a surface used to produce lift and thrust or to steer while traveling in water, air, or other fluid media. The first use of the word was for the limbs of fish, but has been extended to include other animal limbs and man-made devices....
like
rubberNatural rubber is an elastomer that was originally derived from a milky colloidal suspension, or latex, found in the sap of some plants. The purified form of natural rubber is the chemical polyisoprene, which can also be produced synthetically...
or
plasticPlastic is the general common term for a wide range of synthetic or semisynthetic organic amorphous solid materials suitable for the manufacture of industrial products...
, to aid movement through the water in water sports activities such as swimming,
bodyboardingBodyboarding is a kind of wave riding . The average board consists of a small, rectangular piece of hydrodynamic foam. The board can be shaped and adapted to different riding styles, and size of rider...
,
bodysurfingBodysurfing is the art and sport of riding a wave without the assistance of any buoyant device such as a surfboard or bodyboard. Bodysurfers typically equip themselves only with a pair of specialized swimfins that stay on during turbulent conditions and optimize propulsion. Some practitioners also...
,
kneeboardingKneeboarding is a discipline of surfing where the rider paddles on his belly into a wave on a kneeboard, then rides the wave face typically on both knees. The typical kneeboard is between five and six and a half feet in length, with a wide round nose and constructed of Glassfibre over a...
,
riverboardingRiverboarding is the North American name for a boardsport in which the participant is prone on the board with fins on his/her feet for propulsion and steering. This sport is also known as hydrospeed in Europe and white-water sledging in New Zealand...
, and various types of
underwater divingUnderwater diving is the practice of going underwater, either with breathing apparatus or by breath-holding .Recreational diving is a popular activity...
.
ScubaA scuba set is an independent breathing set that provides a scuba diver with the breathing gas necessary to breathe underwater during scuba diving. It is much used for sport diving and some sorts of work diving....
divers use fins to move through
waterWater is an ubiquitous chemical substance that is composed of hydrogen and oxygen and is essential for all known forms of life.In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam. Water covers 71%...
efficiently, as
humanHumans are bipedal primates belonging to the species Homo sapiens in Hominidae, the great ape family. They are the only surviving member of the genus Homo. Humans have a highly developed brain, capable of abstract reasoning, language, introspection, and problem solving...
feetThe foot is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion...
provide relatively poor
thrustThrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system.-Examples:...
, especially when the diver is carrying equipment that increases
hydrodynamicIn physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow—the natural science of fluids in motion. It has several subdisciplines itself, including aerodynamics and hydrodynamics...
dragIn fluid dynamics, drag refers to forces that oppose the relative motion of an object through a fluid . Drag forces act in a direction opposite to the oncoming flow velocity...
.
Swimfins,
swim fins,
fins or
flippers are worn on the foot or leg and made from
finA fin is a surface used to produce lift and thrust or to steer while traveling in water, air, or other fluid media. The first use of the word was for the limbs of fish, but has been extended to include other animal limbs and man-made devices....
like
rubberNatural rubber is an elastomer that was originally derived from a milky colloidal suspension, or latex, found in the sap of some plants. The purified form of natural rubber is the chemical polyisoprene, which can also be produced synthetically...
or
plasticPlastic is the general common term for a wide range of synthetic or semisynthetic organic amorphous solid materials suitable for the manufacture of industrial products...
, to aid movement through the water in water sports activities such as swimming,
bodyboardingBodyboarding is a kind of wave riding . The average board consists of a small, rectangular piece of hydrodynamic foam. The board can be shaped and adapted to different riding styles, and size of rider...
,
bodysurfingBodysurfing is the art and sport of riding a wave without the assistance of any buoyant device such as a surfboard or bodyboard. Bodysurfers typically equip themselves only with a pair of specialized swimfins that stay on during turbulent conditions and optimize propulsion. Some practitioners also...
,
kneeboardingKneeboarding is a discipline of surfing where the rider paddles on his belly into a wave on a kneeboard, then rides the wave face typically on both knees. The typical kneeboard is between five and six and a half feet in length, with a wide round nose and constructed of Glassfibre over a...
,
riverboardingRiverboarding is the North American name for a boardsport in which the participant is prone on the board with fins on his/her feet for propulsion and steering. This sport is also known as hydrospeed in Europe and white-water sledging in New Zealand...
, and various types of
underwater divingUnderwater diving is the practice of going underwater, either with breathing apparatus or by breath-holding .Recreational diving is a popular activity...
.
ScubaA scuba set is an independent breathing set that provides a scuba diver with the breathing gas necessary to breathe underwater during scuba diving. It is much used for sport diving and some sorts of work diving....
divers use fins to move through
waterWater is an ubiquitous chemical substance that is composed of hydrogen and oxygen and is essential for all known forms of life.In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam. Water covers 71%...
efficiently, as
humanHumans are bipedal primates belonging to the species Homo sapiens in Hominidae, the great ape family. They are the only surviving member of the genus Homo. Humans have a highly developed brain, capable of abstract reasoning, language, introspection, and problem solving...
feetThe foot is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion...
provide relatively poor
thrustThrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system.-Examples:...
, especially when the diver is carrying equipment that increases
hydrodynamicIn physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow—the natural science of fluids in motion. It has several subdisciplines itself, including aerodynamics and hydrodynamics...
dragIn fluid dynamics, drag refers to forces that oppose the relative motion of an object through a fluid . Drag forces act in a direction opposite to the oncoming flow velocity...
. Very long fins and
monofinA monofin is a type of swimfin typically used in finswimming and free-diving. It consists of a single surface attached to footpockets for both the free-diver's feet.-History and Production:...
s are used by freedivers as a means of underwater propulsion that does not require high
frequencyFrequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency....
leg movement.
Swimfins are also known as "flippers", due to the ambiguity of the word "fin"; "fin" can reference the fins on cars and auxiliary
airfoilAn airfoil or aerofoil is the shape of a wing or blade or sail as seen in cross-section....
s on
aircraftAn aircraft is a vehicle which is able to fly by being supported by the air, or in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil An aircraft is a vehicle which is able to fly by being supported...
. Scuba divers all around the world would generally be familiar with the word "fins".
History
Early inventors, including
Leonardo da VinciLeonardo di ser Piero da Vinci was an Italian polymath, scientist, mathematician, engineer, inventor, anatomist, painter, sculptor, architect, botanist, musician and writer....
and
Giovanni Alfonso BorelliGiovanni Alfonso Borelli was a Renaissance Italian physiologist, physicist and mathematician. He contributed to the modern principle of scientific investigation by continuing Galileo's custom of testing hypotheses against observation...
, toyed with the concept of swimfins.
Benjamin FranklinBenjamin Franklin was one of the Founding Fathers of the United States of America. A noted polymath, Franklin was a leading author and printer, satirist, political theorist, politician, scientist, inventor, civic activist, statesman, soldier, and diplomat...
made a pair of early swimfins when he was a young boy living in Boston, Massachusetts near the
Charles RiverThe Charles River is a river in Massachusetts, USA. It travels through 22 cities and towns in eastern Massachusetts, from Hopkinton to Boston on the Atlantic Ocean.-Route:...
; they were two thin pieces of wood, about the shape of an art
paletteA palette is: ' a rigid, flat surface on which a painter arranges and mixes paints. A palette is usually made of wood, plastic, ceramic or other hard, inert, nonporous material, and can vary greatly in size and shape...
, which allowed him to move faster than he usually did in the water.
Louis de Corlieu in France and
Owen ChurchillOwen Porter Churchill was an American sailor who competed in the 1932 Summer Olympics.In 1932 he was a crew member of the American boat Angelita which won the gold medal in the 8 metre class.- Swim Fin :...
in the United States, working independently of each other, were the first to make swimfins a practical reality. Churchill's design caught the attention of the
United States NavyThe United States Navy is the sea branch of the U.S. Armed Forces. It is one of the seven uniformed services of the United States. As of 31 December 2008, the U.S. Navy had about 331,682 personnel on active duty and 124,000 in the Navy Reserve. It operates 283 ships in active service and more than...
, which issued it to their
Underwater Demolition TeamUnderwater Demolition Teams were a precursor to the current United States Navy SEALs. The UDTs conducted beach and hydrographic reconnaissance, explosive cable and net cutting, explosive destruction of underwater obstacles to enable major amphibious landings, limpet mine attacks, submarine...
s in the early 1940s. Fins of this design can still be found in just about any sporting goods store or
surfSurfing is most commonly known, the term is used for a surface water sport in which the person surfing moves along the face of a breaking ocean wave . However, surfing is not restricted to saltwater, but can sometimes take place on rivers, using a standing wave...
shop.
In
BritainThe United Kingdom of Great Britain and Northern Ireland is a sovereign state located off the northwestern coast of continental Europe. It is an island country, spanning an archipelago including Great Britain, the northeastern part of Ireland, and many small islands...
,
DunlopDunlop Rubber was a company based in the United Kingdom which manufactured tyres and other rubber products for most of the 20th century. It was taken over by BTR plc in 1985. Since then, ownership of the Dunlop brands has been fragmented....
made
frogman'sBritain's commando frogman force is now the SBS, which is part of the Royal Marines. They perform various operations on land as well as in the water....
fins for
World War IIWorld War II, or the Second World War , was a global military conflict which involved a majority of the world's nations, including all great powers, organized into two opposing military alliances: the Allies and the Axis...
, but after the war saw no market for them in peacetime, and, after the first supply of war-surplus frogman's kit was used up, the British public had no access to swimfins (except for home-made attempts such as gluing marine plywood to plimsolls), until
Oscar GugenOscar Gugen was a founder of the British Sub-Aqua Club.He was born in 1910 of an Austrian father and French mother. He started as a hotel kitchen hand in Austria, peeling carrots. By the age of 21 he was a hotel director in the south of France....
began importing swimfins and swimming
gogglesGoggles 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 in woodworking. They are often used in snow sports as...
from
FranceFrance , officially the French Republic , is a country located in Western Europe, with several overseas islands and territories located on other continents. Metropolitan France extends from the Mediterranean Sea to the English Channel and the North Sea, and from the Rhine to the Atlantic Ocean...
.
In 1946
LillywhitesLillywhites is a sports retailer based at Piccadilly Circus, London, United Kingdom. It is currently a division of Sports World International-History:...
imported about 1100 pairs of swimfins; they all sold in under 3 months.
In 1949 Ivor Howitt or a friend of his mailed to the Dunlop Rubber Company for swimfins; Dunlop answered that they had no plans to make swimfins and saw no use for them in peacetime. Howitt made his own swimfins with
innertubeCBS Innertube is a broadband video channel launched by CBS in May 2006. The channel offers original Web-only shows, as well as rebroadcasts of CBS's regular shows.This service is currently only available in the United States...
rubber stretched across a frame of stiff rubber tube.
Types of swim fins
Types of fins have evolved to address the unique requirements of each community using them.
Scuba diversScuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater for recreation, commercial or industrial reasons.Unlike early diving, which relied exclusively on air pumped from the surface, scuba...
, in particular, need large wide fins to overcome the water resistance caused by their
diving equipmentThe fundamental item of diving equipment used by divers is the SCUBA equipment, such as the Aqualung or Rebreather. There are other important pieces of equipment that make diving safer, more convenient or more efficient.-Scuba life support:...
;
snorkelersSnorkeling is the practice of swimming on or through a body of water while equipped with a diving mask, a shaped tube called a snorkel, and usually swimfins. In cooler waters, a wetsuit may also be worn...
need lightweight flexible fins; ocean swimmers, bodysurfers, and
lifeguardA lifeguard is a person responsible for overseeing the safety of the users of a body of water and its environs, such as a swimming pool, a water park, or a beach. This differentiates them from life savers who partake in similar activities as a sport or practical life skill...
s favor smaller designs that stay on their feet when moving through large surf and that make walking on the beach less awkward. In general there are two main groups of fins; full foot and open heel. Full foot fins fit like a shoe, and are designed to be worn over bare feet. They are commonly used for surface swimming, and are in non adjustable sizes. Open heel have a foot pocket with an open heel area, and the fin is held to the foot by springs or straps. They can be worn over boots, and are common in diving. Many companies design fins with the same fin architecture but a choice of heel type. Other, more specific design trends are listed below.
Paddle fins
These are the most basic fins; a pair of simple stiff plastic, composite, or rubber blades that work as extensions of the feet while kicking. Some paddle fins have convoluted channels and grooves to improve power and efficiency though it has been shown that the desired effect does not occur. Paddle fins are widely believed to be the most versatile and have improved swimming economy in men. Tests in women showed a more flexible fin to be more economical, most likely due to lower leg power.
Vented fins
Vented fins were first designed in 1964 by
Georges BeuchatGeorges Beuchat was a French inventor, diver, businessman and emblematic pioneer of underwater activities and founder of Beuchat....
and commercialised as
Jetfins. Vented fins are paddle fins which have vents at the base of the foot pocket that allow for the passage of water during recovery kicks, but prevent passage during power strokes due to the blade angle. Recovery kicks require less effort so kick efficiency is improved. The Jetfin tradename and design were sold to
ScubaproScubapro is a manufacturer of scuba gear. It was founded in the United States in 1963 by Gustave de la Valle, Beuchat representative in USA and Dick Bonin...
in the 1970’s. There is a hazard when swimming among debris, that long thin debris can get threaded through the vent.
Split fins
Some swimfins have the end of the blade split. In hydrodynamic principle, split fins operate similarly to a
propellerA propeller is a type of fan which transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of the airfoil-shaped blade, and air or water is accelerated behind the blade...
, by creating suction and
liftA fluid flowing past the surface of a body exerts a force on it. Lift is defined to be the component of this force that is perpendicular to the oncoming flow direction. It contrasts with the drag force, which is defined to be the component of the fluid-dynamic force parallel to the flow...
forceIn physics, a force is any agent that causes a change in the motion of a free body, or that causes stress in a fixed body. It can also be described by intuitive concepts such as a push or pull that can cause an object with mass to change its velocity , i.e., to accelerate, or which can cause a...
s to move the swimmer forwards. The theory is that water flowing toward the center of the fin's "paddle" portion also gains speed as it focuses, creating a "scooping" or channeling effect. Due to the nature of the design this type of fin is also commonly used for snorkeling due to the fins being able to break the tension of the water with less effort than other designs when swimming along the surface, allowing the swimmer to conserve energy. Split fins are sometimes called "Biofins", although "Biofins" is a tradename.
Freediving fins
These are very similar to paddle fins, except they are far longer, and designed to work with slow stiff-legged kicks that conserve energy and oxygen. Though primarily intended for high efficiency at variable depths, they can still deliver impressive acceleration if necessary. The vast majority are made in the "full-foot" design with very rigid footpockets, which serves to reduce weight and maximize power. Freediving fins are commonly made of plastic, but are also often made from materials such as fiberglass and
carbon fiberCarbon fiber is a material consisting of extremely thin fibers about 0.005–0.010 mm in diameter and composed mostly of carbon atoms. The carbon atoms are bonded together in microscopic crystals that are more or less aligned parallel to the long axis of the fiber...
.
Monofins
A monofin is typically used in
finswimmingFinswimming is the progression of a swimmer using monofins or normal swimfins either on the water surface or underwater, using only muscle strength. It is a discipline of underwater sports. The competition distances are same as for swimming...
and
free-divingFreediving is any of various aquatic activities that share the practice of breath-hold underwater diving. Examples include breathhold spear fishing, freedive photography, apnea competitions and, to a degree, snorkeling...
. It consists of a single
surfaceIn mathematics, specifically in topology, a surface is a two-dimensional topological manifold. The most familiar examples are those that arise as the boundaries of solid objects in ordinary three-dimensional Euclidean space R
3 — for example, the surface of a ball...
attached to footpockets for both the free-diver's feet. Monofins can be made of glass fibre or carbon fibre. The diver's
muscleMuscle is the contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
power and swimming style, and the type of activity the monofin is used for, determine the choice of size, stiffness, and materials.
Less usual types
Open and closed heel fins are predominant, but there is a range of fins which have specialised blade attachment architecture. These include (these names are tradenames):
Delfins
The Mor-Fin Corporation produces "delfins", which are swimfins that end short and to the end is attached a shape like a fish's forked homocercal caudal fin. It is based on the anatomy of a
dolphinDolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from and , up to and . They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly...
's fluke.
commercial site
Shinfins
These fins are attached to the ankle and rest against the (anatomically) upper side of the foot, to avoid leg
crampFor the heraldic device, see cramp ; for the band, see The CrampsCramps are unpleasant, often painful sensations caused by contraction or over-shortening of muscles...
s and to reduce foot strain:
commercial site.
Force fins
These fins are attached to the instep of the foot, and the whole of the toes down to the metatarsal heads protrude from a hole in the shoe part, to let the foot flex:
commercial site.
Flipfins
Flipfins are a modern USA-made type of open-heel swimfin designed to allow easy walking on land. Its blade and foot part are separate: the blade hinges onto the foot part at each side, roughly on the level of the metatarsal heads, and when swimming is held in line by a clip on the front of the foot part. On land or when wading the blade can be unclipped and hinged vertically so it does not interfere with walking:
commercial site, with images
Training
The upper limit of a diver's fin-kick thrust force using a stationary-swimming
ergometerErgometer may refer to:*Exercise machine, equipped with an apparatus for measuring the work performed by exercising*Indoor rower, called an ergometer by rowers* An instrument for measuring the amount of work done by human muscles-See also:...
was shown to be . Resistive respiratory muscle training improves and maintains endurance fin swimming performance in divers.
See also
- Human swimming
- PowerSwim
The PowerSwim is a device somewhat like two pairs of long thin airplane wings, one pair at each end of an axis. The axis is fastened to a scuba diver's shins by straps round his legs. The longer pair of wings is at his hips and the shorter pair is at his ankles...
, a device somewhat like two pairs of long thin airplane wings fastened to a scuba diver's hips and legs
- Diving equipment
The fundamental item of diving equipment used by divers is the SCUBA equipment, such as the Aqualung or Rebreather. There are other important pieces of equipment that make diving safer, more convenient or more efficient.-Scuba life support:...
- Scuba equipment