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BACKFLY STROKE
The backfly® is a swimming stroke swum on the back, with both arms moving symmetrically, accompanied by the dolphin kick. It is not swimming stroke used in competitive events regulated by FINA yet, but it can be soon because the stroke swum on the back and at least as fast and spectacular as backstroke or butterfly.

While other styles like the breaststroke, front crawl, or backstroke can be swum adequately by beginners, the backfly as butterfly is a more difficult stroke that requires good technique as well as loose muscles. Despite being a difficult type of swimming stroke, it is also recommended as a rehabilitation swim, as it specifically relaxes the back and skeletal muscles with the help of dolphin movement. It is the newest swimming stroke in 2022 created and finalized by dr. Marcell Grundtner.

The swimming stroke backfly® has a similar start as backstroke, has a special new turn and is similar to an upside down butterfly.

There is no information yet that the peak speed of the backfly is how fast but there are several investigation of the peak speed of the butterfly which is faster than the front crawl due to the synchronous pull/push with both arms and legs, which is done quickly. It is the same in backfly with the difference that the dolphin happens on its back, so the buoyancy helps it move better.

BODY POSITION
We can't speak about a standard body position in the case of backfly, because if we compare it either to the arm stroke or the kick it is always changing. However it can be well characterized as a wave like movement. Its determinant factors are the amplitude and wavelength. The longer the wavelength is the more effective the movement is, but we can't say the same about the amplitude.

The downward and upward movements of the swimmers' body shouldn't be exaggerated as this could increase drag, and the weight in the water. The hips shouldn't be in a too high position, and the head shouldn't be in a too low position. The wave like movement and the body position are good if the head sinks together with the arms then the arms are doing the entry and the hip raise just under the water surface during the first up kicking.

When the swimmer finishes the second up kick the hips are not in a too deep, or a too high position and the legs are not in a too high position in the water. The swimmer's body should be as straight as it can be during the propulsive phases of the arm stroke - that is the upsweep and the push.

ARMSTROKE
There are underwater parts and above the water parts of the backfly stroke’s armstroke:

underwater parts are: entry, downsweep, catch, upsweep, push, and release,

above the water part is: recovery

II.1       ENTRY
The swimmer's hands enter the water in the shoulder line or in a little bit closer position with extended elbow. Palm faced down, out, and a little bit down.

II.2       DOWNSWEEP
The arms enters the water at once in the shoulder line and are extended, with the wrists and the little fingers turned a little bit down, the palms are faced out to the side and back. Fingers are closed. After the entry, the forearms and the hands move down and out and the palms are faced back. During this movement the arms bend gradually till the catch. The hands are in a deep position and out of the shoulder line at the catch. The wrists are straight when the catches are made. After the hands enter the water, their speed decelerates during the movements until the catches are made. The point where the propulsion begins is called catch.

II.3       UPSWEEP

The hands move up, and back, and in, drawing a curve line. The arms continue their flexing at the elbows until the angle is between 80 and 90 degrees by the end of these movements. The hands rotate from down, and back to up, and back. The wrists remain straight. The hands speed are accelerated during this movement. Turning in the arms are an important thing, and at this time the thumbs lead the movement.

II.4       PUSH (rotation)
When the hands reach the top point of the previous movement, the hands turn down, and back in a curve line until they are extended. The palms are rotated down and out during the pushes. The hands speed decrease during the transition to the push and then accelerate during that movement. The palms are faced out at the end of this movement, with the little fingers up. The (rotational) pushes help to achieve a series of joint movements of the body and the dolphin. If the swimmer performs this phase of movement correctly, it will have the right speed when the arms are raised again.

II.5       RELEASE
Once the pushes have been completed, the hands move up toward the surface, led by the thumbs. These phases are completed, when the hands approache the rear of the thigh. The finish of the pushes generate a propulsive force as the arms come closer to the thigh and turn the palm outward and begin to raise that. The speed of the hands decelerate.

II.6       RECOVERY
The recovery are done in the shoulder line with extended arms led by the thumbs. During the recovery  the palms slowly rotate from the thumbs to the little fingers for more optimal water grip. The speed of the hands during recovery are constant.

TIMING OF ARMS
The arms perform the same movement at the same time. The propulsion of the body can only be maintained for half an arms circle, but this is replaced by the movement of the dolphin.

BREATHING
The swimmer looks up and forward when the recovery is made, and begins to bend the head backwards at the entry. If the bending of the head is delayed during the downsweep the timing is not good. Moving down from the water surface the swimmer continues to bend the head back at the downsweep. The head breaks again the water surface during recovery. At the finish of the recovery and during the first half of the entry the swimmer begins to inhale. It is also important to look up, and forward during the inhalation otherwise the hips might sink and cause the drag to increase.

The swimmer puts back the head under the water in the second half of the entry.

The exhaling occurs through the mouth and the nose with an accelerating speed between the downsweep and the first half of the push, while the inhaling occur through the mouth with an even speed during the first half of the recovery.

The breathing of backfly - of course - increase the oxygen uptake, but the weight of swimmers in the water, and the drag are increased at the same time. While strokes without breathing makes it possible to reach a horizontal body position, to decide when to take a breath or not swimmers must find the best balance between these questions. Swimmers can take a breath at every stroke or take a breath at every second stroke or mix between these two types of breathing.

KICKING
The dolphin kick is a wave like movement. It consists of an up kick and a down kick. Swimmers do two dolphin kicks during one complete arm cycle. The first one is done during the push, and the second one is done during the recovery. The first up kick accelerates the body and the second helps to maintain the hips on the water surface and start the entry during the recovery. It hasn't been proved yet whether the down kick is propulsive.

V.1      Up kicking
The first up kick is generally bigger. This is a whip like action, which begins with a flexion at the hips, followed by the flexion of the knees and their extension, and finally the flexion of the ankles. The kick begins with the flexion at the hips when the swimmer's feet are under the bodyline. The knees are flexed; the feet are in a plantar flexion, inward rotated position. The thighs begin to move up; legs are extending and ready to finish the up kick.

The flexibility of the ankles play an important role in the effectiveness of the dolphin kick according to most experts, it is more important than the strength of the legs. Swimmers should open their knees at the first half of the up kick and close them by the end of it. There is a reason why this happens: when knees open feet act better plantar flexed and inward rotated, and can be maintained in this position longer if the thighs turn in during the leg extension.

An exaggerated down and up hip movement can increase drag. Swimmers have to try and avoid this. The hips moves up close to the water surface during the first up kick and should just keep up during the secound up kick.

V.2      Down kicking
This begins immediately after the up kick, when the legs are nearly extended. The lowering of the legs is done with the help of the hip extension muscles and the pressure of water above the legs. The water pressure keeps the feet in extended position between plantar and dorsal flexion. The swimmer should not bend the knees during the up kicking, but lifts the legs to the hip-line. The next down kick starts at this time.

UNDERWATER DOLPHIN KICKING
Swimmers may use underwater dolphin kick till 15m at about 70-120 cm deep. The dolphin kick is on the back, it is shorter and faster than any other delphin. The swimmers should finish doing the underwater dolphin kicks and begin the armstroke when they are close to the water surface. In that way they come through the surface without reducing their speed.

TIMING OF DOLPHIN KICKS
In case of Backfly® there are two dolphin kicks during one complete arm stroke. The first kick is done during the entry, downsweep, upsweep and push. The second is done during the release, and the recovery.

The first down beat begins at the end of recovery, continues during the entry. The first up beat is done during the upsweep and push. The second down beat begins and finishes at the release. The second up beat is done during the recovery. The two dolphin kicks are not equal. The more efficient a backflyer is, the more equal the two dolphin kicks are.

Differences between the two dolphin kicks can be rather explained with the differences of the body position than with the differences between efforts.

START
The Backfly® start is the same start of backstroke from the water. The swimmer faces the wall and grabs the grips on the block. The legs are placed shoulder width apart on the wall with both heels slightly off the wall. Just before the starting signal, the swimmer pulls their head closer to the start block, while keeping the knees bent at a 90-degree angle. Swimmers can choose keeping one foot slightly lower than the other during the start.

For the takeoff, the swimmer pushes their hands away from the block and swings their arms around sideways to the front. At the same time, the swimmer throws their head to the back. The swimmer then pushes away from the wall with their feet. Ideally, the swimmer's back is arched during the airborne phase so that only the feet and the hands touch the water while the rest of the body is above the water line. This reduces drag and permits a faster start. The feet can now be above the water, but not above or curled over the lip of the pool gutter.

After the start, the swimmer is completely underwater. Due to increased resistance at the surface, experienced swimmers usually swim faster underwater than at the surface. Most swimmers use a dolphin kick underwater 15 meters after the start and after every turn, as this provides more forward movement than any other kick. The swimmer's head must break the surface before 15 m.

TURN AND FINISH
During turns and during the finish, both hands must simultaneously touch the wall while the swimmer remains swimming face up. The swimmer touches the wall with both hands while bending the elbows slightly. The bent elbows allow the swimmer to push himself or herself away from the wall and by pulling up the two legs can turn. At the same time the legs are pulled closer and moved above of the body towards the wall. The legs touch the wall and the hands are at the front. The swimmer is under water and lies on the breast, or nearly so. Then the swimmer pushes off the wall, keeping a streamline position with the hands to the front and turns the body 180 degrees longitudinally while underwater dolphin kicking. Similar to the start, the swimmer is allowed to swim 15 m underwater before the head must break the surface. Most swimmers dolphin kick after an initial gliding phase.

The finish requires the swimmer to touch the wall with both hands at the same time, in the same horizontal plane.