Human swimming typically consists of repeating a specific body motion or swimming stroke to propel that body forward. There are many kinds of strokes, each defining a different swimming style or crawl
In high school, collegiate, and Olympic swimming, there are two undulating strokes (breaststroke, and butterfly stroke,) and two alternating strokes (front crawl and backstroke.)
Most strokes involve rhythmic and coordinated movements of all major body parts — torso, arms, legs, hands, feet, and head. Breathing typically must be synchronized with the strokes, too. It is possible, however, to swim by moving only legs without arms or only arms without legs; such strokes may be used for special purposes, for training or exercise, or by amputees (paralympians) and paralytics
- Front crawl: the fastest style for swimming on the surface. Done while face down. The arms alternate while the legs perform a flutter kick.
- Dolphin crawl: Similar to front crawl, but with a dolphin kick. One kick per arm or two kicks per cycle. This style is often used in training.
- Catch up stroke: A variation of the front crawl where one arm always rests at the front while the other arm performs one cycle. This can also be used as a drill when training in competitive swimming.
- Head-high crawl (also known as the water polo stroke, lifeguard approach stroke, or Tarzan drill): This stroke is used for water polo, lifeguards to keep the victim in sight, or those who simply want to see where they're going and breathe with ease. It is similar to front crawl, but with head above the water. This can also be used as a drill when training in competitive swimming.
- Trudgen: The trudgen is similar to the front crawl, except that it is paired with a scissors kick, similar to that used in the sidestroke.
- Trudgen crawl: similar to the trudgen, but with the use of a flutter kick (up and down leg kick) between the scissor kicks.
- Double trudgen: Similar to the trudgen, but the sides of the scissors kick alternate.
- Double trudgen crawl: Similar to the double trudgen, but with a flutter kick between the scissors kick alternate.
- Butterfly stroke: performed face down in the water. The legs perform a dolphin kick and while the arms move in a forward circle at the same time.
- Slow butterfly (also known as "moth stroke"): Similar to butterfly, but with an extended gliding phase, Breathing during the pull/push phase, return head into the water during recovery. This style uses two kicks per cycle.
- Breaststroke: performed face down in the water without rotating the torso. The arms stay in the water and move synchronously, while the legs perform a whip kick. It is possible to keep the head elevated out of the water throughout the stroke, although the head usually dips in and out.
- Inverted breaststroke: Similar to elementary backstroke, but with a breaststroke kick and arm motions.
- Backstroke: Done while lying on the back. One arm reaches behind the head with a fingertip entry while the other arm is by the side. The legs perform a flutter kick.
- Elementary backstroke: Both arms move synchronized (They begin out like an airplane, then go beside the body like a soldier then they run up the sides and back out to an airplane position) with whip kick (breaststroke kick).
- Inverted butterfly: Similar to elementary backstroke, but with a dolphin kick. This is often used for training.
- Back double trudgen: Similar to the backstroke, but with a scissors kick to alternating sides.
- Old English Backstroke : Lying on back, breaststroke legs and butterfly arms
- Forward backstroke: Done lying on back and floating. Arms parallel to the surface, moving in the opposite direction to backstroke.
- Sidestroke: On the side, pull the water as if with a rope with arms going out and stopping in the middle while ensuring that the strokes are most hydrodynamic when moving towards the desired location, and pushing the most water when moving away from the location. In addition, the legs are performing a scissors kick, which is like breaststroke kick, but sideways.
- Dog paddle: face over water and paddling with alternate hands, often with the nose and mouth above the water. This stroke can be used in reverse to propel the body feet first.
- Human stroke: Similar to the dog paddle, but the arms reach out more and pull farther down.
- Survival travel stroke: Alternating underwater arm stroke, one cycle for propulsion, one for a lift to stay on the surface. This style is slow but sustainable.
- Breast feet first strokes: With legs extended, use the arms with a pushing, flapping, clapping or uplifting motion.
- Snorkeling: Swimming on the breast using a snorkel, usually in combination with masks and fins. Any stroke on the breast can be used, and there is no need to lift or turn the head for breathing.
- Finswimming is the progression of a swimmer using fins either on the water surface or underwater. Finswimming is usually done on the breast.
- An arm and a leg: is the progression of a swimmer clasping one leg with the opposite arm, and using breaststroke movements with the remaining arm and leg.
- Flutter back finning: Symmetrically underwater arm recovery with flutter kick.
- Flicker kick: Concerning human morphology oscillatory flutter kick is more suitable, hence all swimming techniques exert vertical oscillation with upward propelling. Flicker kick, as vibration of both, hands and legs, with slight deviation of arms within regular undulation will produce powerful horizontal dynamics. Swimmer by propelling is not just vibrating, this is proved to be insufficient, but rather producing undulating waves (horizontal instead of vertical). The initial move is made by shoulders gliding backward and curve. Meandering is transmitted to the hips and legs. Undulation is most pronounced between the shoulders and thighs. At the end of swimming cycle, legs produce flicker kick as collateral to undulatory movement. See also eel stroke.
- Feet first swimming: A very slow stroke on the back where a breaststroke movement with the arms propels the body forward feet first. Also the arms can be lifted out of the water and pulled backwards together with a scooping movement. Alternatively, the arms can be raised behind the head, alternately or together pushing with the hands, propelling the body. Similarly, the hands can be brought together in a clapping action. These strokes are often used for training.
- Eel style: start position of swimmer is backward, hands to body and legs close floating. Swimmer then starts to undulate first with hand and shoulders then trespassing undulation on legs. The propulsion force is mainly generated by hands, which stay all the time close to body. Swimmer tries to relay on gliding flow of water moving easily and swiftly. Legs do not perform flutter stroke as it will create force opposite to undulation. Efficiency is achieved by undulating along the whole body, intermittently and at intervals. Once the body is introduced in undulation, it will soon achieved optimal velocity. The purpose of transfer from preparation to propulsion phase is to generate gliding flow, which swimmer will use as an additional lift in moving forward and up. Swimmers in nature use body undulations to generate these propulsive and maneuvering forces. The anguilliform kinematics is driven by muscular actions all along the body[dubious ]
- Corkscrew swimming: Alternating between front crawl and backstroke every arm. This leads to a constant rotation of the swimmer. The stroke is used mainly for training purposes and is also sometimes known as Newfie Stroke, referring to Newfoundland. When rotating every third stroke, this is called waltz crawl.
- Gliding: The swimmer is stretched with the arms to the front, the head between the arms and the feet to the back. This streamlined shape minimizes resistance and allows the swimmer to glide, for example after a start, a push off from a wall, or to rest between strokes.
- Sepia bone: Sepia bone could be effective as drifting technique, in steering and floating in the fast flow, using only hand to navigate the stream, complementary as passive to more proactive swimming techniques.Ibid.
- Turtle stroke: On the breast, extend right arm then pull, after pushing with the left leg (while opposite limbs are recovering), then opposite limbs repeat this process, i. e. left arm pulls after right leg pushes. Uses muscles of the waist. Head can easily be above or below water: this is a slow but very sustainable stroke, common in turtles and newts.
- Octopus stroke: The swimmer starts from floating posture backward spreading arms and feet in spread position, arms raised further up to the maximum momentum, keeping them parallel to the surface, in the propulsive phase returning the same way, hands to the body and legs merging. Legs opening to the 45 degree returning then returning and closing, arms smoothly from 90, 120 degrees of leg axis, then cling to the legs. More economical means of motion involves alternative movements of leg and arms, first arms then legs (Dalton, 1918). Effective swimming, however, implies their parallel movement.
Special purpose styles
A number of strokes are only used for special purposes, e.g. to manipulate an object (a swimmer in distress, a ball), or just to stay afloat.
Swimming underwater is faster than swimming on the surface. Underwater swimming is not its own category in the Olympics, but in the 1988 Olympics several competitors swam much of the backstroke race underwater. After that, the Olympics created a rule that swimmers are only allowed to stay underwater for the first 10 meters (later changed to 15 meters) after a start or a turn.
Any style with underwater recovery can be done underwater for certain distances depending on the need for air. Underwater swimming on the back has the additional problem of water entering the nose. To avoid this, the swimmer can breathe out through the nose or wear a nose clip. Some swimmers can close their nostrils with the upper lip or with the compressor naris muscles.
- Dolphin kick: this is the style that is usually used at the beginning of the race, to hold on to the speed the swimmer generate by pushing off the walls at the start and the turns. The feet kick while the arms keep still while extended in front of the head, with the hands together.
- Fish kick: Similar to the dolphin kick, but performed while on the swimmer's side. This may be the fastest form of swimming. Swimming creates vortices which propel the swimmer forward. In the dolphin kick, the vortices go up and down, where they're disturbed when they hit the surface of the water or the bottom of the pool. But with the fish kick, they go sideways, where there are no obstructions.
- Pull-down Breaststroke: most common swim stroke underwater as it requests very low energy. Main application is for dynamic apnea (DNF)
- Sea lion stroke: this swimming stroke is primarily performed with sculling, arms at the side along the bodyline and strongly supported with flutter kicks in a contralateral sequencing. It can be identified to the sea lion swimming style. It's very effective to swim through narrow underwater places.
Swimming hydrodynamics have significantly applied BCF (body-caudal fin swimming) to techniques. In addition research on undulatory motion, undulatory Body-caudal fin anguilliform, and undulatory Median-paired fin give interesting conclusions. These natural modes are seen as an alternative to BCF techniques introducing some missing elements as buoyancy, gliding and floating to complement the scale of man’s hydrodynamics.
The study draws a conclusion from hydrodynamic properties of cephalopods as implied to human kinetics, discerning significant patterns, like floating, puddle, undulation or efficiency. In biomechanical aspect medusoid and anguilliform shows positive results: low Reynolds number, low viscous forces, stability, great laminar flow, linear momentum and efficient velocity.
- Lifesaving stroke: Similar to the side stroke, but only the bottom arm moves while the top arm tows a swimmer in distress.
- Lifesaving approach stroke (also known as head-up front crawl or Tarzan stroke): Similar to the front crawl, but with the eyes to the front above the water level, such as to observe the surroundings as for example a swimmer in distress or a ball.
- Pushing rescue stroke: This stroke helps to assist a tired swimmer: The tired swimmer lies on the back and the rescuer swims a breaststroke kick and pushes against the soles of the tired swimmer (not taught or recognized by the RLSS body governing UK lifeguarding).
- Pulling rescue stroke: This stroke helps to assist a swimmer in distress. Both swimmers lie on the back, and the rescuer grabs the armpits of the swimmer in distress and performs a breaststroke kick (on the back) for forwarding motion. The kick has to be not too shallow as otherwise the victim will be hit.
- Extended Arm Tow (unconscious victim): swimming sidestroke or breaststroke on their back, the rescuer holds the head with a straight arm, the hand cupping underneath the chin, and ensures that the mouth and nose are out of the water.
- Arm Tow: the rescuer swims sidestroke, behind the casualty holds the upper right arm of a casualty with their left hand or vice versa, lifting the casualty out of the water.
- Vice Grip Turn and Trawl: used on a victim with a suspected spinal injury. The lifeguard approaches slowly to the victim (who is usually face down in water), places one hand on the victim's chin, with arm pressed firmly against the victim's chest. The other hand is placed on the back of the victim's head with the arm down the victim's back. Both arms press together (like a vice), and the lifeguard uses his feet to begin moving forward and then rolls under the victim to come up alongside her or him, but with the victim now on his or her back. (This is one of the hardest lifesaving maneuvers, as the grip must be perfect on the first attempt; otherwise, the victim may be given further spinal damage, such as paralysis.)
- Clothes swimming: The swimmer is wearing clothes that restrict movement when wet, i.e. almost all clothes. This is done to practice situations where the swimmer fell in the water dressed or the rescuer did not have time to undress. Due to the restricted movement and the weight of wet clothes out of the water, an overarm recovery is not possible. Most swimmers swim breaststroke, but any stroke with underwater recovery is feasible.
- Rescue tube swimming: The lifeguard pulls a flotation device, which is pushed forward when approaching the victim.
Without forward motion
- Survival floating (also known as dead man float and drownproofing): Lying on the prone (face down in water) with minimal leg movement, and staying afloat with the natural buoyancy. Lift the head to breathe only then back to floating. This style is only to stay afloat and to rest.
- Back floating: Similar to the survival floating, except on the back.
- Treading water: The swimmer is in the water head up and feet down. Different kicks, such as the eggbeater kick, and hand movements are used to stay afloat. This is useful to keep the head out of the water for a better view or to catch an object as for example in water polo.
- Sculling: This is a figure 8 movement of the hands for forward motion or upward lift. Used in surf lifesaving, water polo, synchronized swimming and treading water.
- Turtle float: The knees are raised to the chest and encircled by the arms.
- Jellyfish float: Holding the ankles with the hands.
- Head first surface dive
- Dalton, F. E. (1918). Swimming scientifically taught, Funk and Wagnalls Company, New York and London
- Encyclopedia of Marine Mammals, p. 1142, at Google Books
- 31. Lindsey, C. C. (1978) Form, function and locomotory habits in fish, in Fish Physiology VII Locomotion, W. S. Hoar and D. J. Randall, Eds. New York: Academic, 1–100