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Backstroke
Introduction Backstroke
 The backstroke was first demonstrated at the Olympic Games in Stockholm in
the year of 1912 through the American swimmer Hebner. Because he won the race, his
innovative technique was taken very seriously. For a long time the backstroke was swum
witch stretched arms. Nowadays you only see the bent armtechnique, especially at matches.
Because the pull through of the arms is executed via the body, there is a tendency to
swing. Because of this, a good legstroke is essential to compensate the swinging, even
more than at the freestyle. Besides, the damming function of the legs remains very
important.
Technique Backstroke
Upper view of professional backstroke movementIn the initial position, the swimmer lies
flat on his back, arms stretched forward, and legs extended backwards.
Arm movement
In backstroke, the arms contribute most of the forward movement. The arm stroke consists
of two main parts: the power phase (consisting of three separate parts) and the recovery.
The arms alternate so that always one arm is underwater while the other arm is recovering.
One complete arm turn is considered one cycle. From the initial position, one arm sinks
slightly under water and turns the palm outward start the Catch phase (first part of the
power phase). The hand enters downward about ten inches, catching the water.
During the power phase the hand follows a semi-circular path from the Catch to the side of
the hip. The palm is always facing away from the swimming direction, and the elbow always
points downward towards the bottom of the pool. This is done so that both the arms and the
elbow can push the maximum amount of water back in order to push the body forward. At the
height of the shoulders the upper and lower arms should have its maximum angle of about 90
degrees. This is called the Mid-Pull of the power phase.
The Mid-Pull phase consists of pushing the palm of the hand as far down as possible with
the fingers pointing upward. Again, the goal is to push the body forward against the
water. At the very end of the Mid-Pull, the palm flaps down for a last push forward down
to a depth of 45 cm, creating the Finish of the Power phase. Besides pushing the body
forward this also helps with the rolling back to the other side as part of the body
movement. During the power phase, the fingers of the hand can be slightly apart, as this
will increase the resistance of the hand in the water due to turbulence.
To prepare for the recovery phase, the hand is rotated so that the palms point towards the
legs and the thumb side points upwards. At the beginning of the recovery phase of the one
arm, the other arm begins its power phase. The recovering arm is moved in a semicircle
straight over the shoulders to the front. During this recovery, the palm rotates so that
the small finger enters the water first and the palms point outward. After a short gliding
phase, the cycle repeats with the preparation for the next power phase.
A variant is to move both arms synchronized and not alternating, similar to an upside down
butterfly stroke. This is easier to coordinate, and the peak speed during the combined
power phase is faster, yet the speed is much slower during the combined recovery. The
average speed will usually be less than the average speed of the alternating stroke.
Another variant is the old style way of swimming backstroke, where the arm movement formed
a complete circle in a windmill type pattern. However, this style is nowadays no longer
used for competitive swimming, as a lot of energy is spent on pushing the body up and down
instead of forward. Furthermore, the added strain on the shoulder is considered less than
ideal and can lead to injuries.
It is also possible to move only one arm at a time, where one arm moves through the power
and recovery phases while the other arm rests. This is slow, but it is used frequently to
teach students the movement, as they have to concentrate on only one arm.
Leg movement
The leg movement in backstroke is similar to the flutter kick in front crawl. They make a
small contribution to the forward speed, yet are very significant for stabilizing the
body.
The leg stroke is also alternating, with one leg sinking down straight to about 30 degree
out of the horizontal. From this position the leg makes a fast kick upward, slightly
bending the knee at the beginning and then stretching it again in the horizontal. However,
there are also frequent variants with four or only two kicks per cycle. Usually, sprinters
tend to use 6 kicks per cycle, whereas long distance swimmer may use less.
It is also possible to use a breaststroke kick or a butterfly (dolphin) kick, although
this is rare except the butterfly kick after the start and the turns. Breaststroke kicks
are most comfortable if the arms are used synchronized, as the breaststroke kick has
difficulty to compensate for a rolling movement due to alternating arm cycles. The
butterfly kick can be done slightly to one side depending on the rolling of the body.
Breathing
Breathing in backstroke is very easy, as the mouth and nose are almost always over water.
Competitive swimmers breathe in through the mouth during the recovery of one arm, and
breathe out through the mouth and nose during the pull and push phase. This is done to
clear the nose of water.
Body movement
Due to the asynchronous movement of the arms, there is a roll of the body around its own
axis. This is normal and helps swimming effectively. The overall position of the body is
straight in the horizontal to reduce drag. Beginners frequently let their posterior sink
too low and increase drag, because to avoid this the upper legs have to be moved to the
extreme down position at each kick even with a little help by the back and the foot tips
have to be fixed in the extreme lower position. And the head is held out of the water to
act as a counter-weight.
Backstroke Start
Backstroke start, waiting for the signalThe backstroke start is the only start from the
water. The swimmer faces the wall and grabs part of the start block or the wall with his
hands. Ideally, there are grips on the block for this purpose. The legs are placed in
shoulder width onto the wall with both heels slightly off the wall. The moment before the
start the swimmer pulls his head closer to the start block, while keeping the knees bent
at a 90 degree angle. Some swimmers prefer to keep one foot slightly lower then the other
during the start, however, keeping both feet at an equal level is perfectly acceptable.
For the takeoff, the swimmer pushes his hands away from the block, and swings his arms
around sideways to the front. At the same time he throws his head to the back. Only a
minimal delay afterwards, the swimmer pushes himself away from the wall with his feet.
Ideally, the swimmers 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
the drag and allows the swimmer to start faster.
After the start, the swimmer is completely underwater. Due to the increased resistance at
the surface, the speed under water may for an experienced swimmer be faster than at the
surface. Therefore, most experienced swimmers stay in backstroke competitions under water
up to the limit set by FINA to be 15 meter after the start and every turn. Most swimmers
swim a butterfly kick under water, as this provides more forward movement than the flutter
kick. The underwater phase includes the risk of water entering the nose, which gives an
unpleasant feeling. Most swimmers breathe out slightly through the nose to stop water from
entering. It is also possible to use a nose clip. Some swimmers can close their nostril
with their upper lips.
The swimmer must break the surface before 15 m. The swimmer starts swimming with one arm,
followed by the other arm with half a cycle delay. The swimmer continues in regular
swimming style, staying on the back for the entire time except the turns. One part of the
swimmer must break the surface at any time.
Backstroke Turn and Finish
Approaching the wall has the problem that the swimmer cannot see where he is going.
Most competitive swimmers know how many strokes they need for a lane, or at least how many
stroke after the signal flags or the change in color of the separating lines. Turning the
head is also possible, but slows the swimmer down.
When approaching the wall, the swimmer is allowed to turn to the breast and make one
push/pull phase with one arm. Next the swimmer makes half a tumble turn forward, resting
the feet against the wall. The arms are in the forward position at this time, and the
swimmer pushes himself off the wall. Similar to the start, the swimmer can remain up to 15
m under water, with most swimmers using a butterfly kick for speed.
For the finish, the swimmer must touch the wall while lying on his back, less than 90
degrees out of the horizontal.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article
"Backstroke"
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