Long jump
The long jump (formerly called "broad jump") is an
athletics
(track and field) event in which athletes combine speed,
strength, and agility in an attempt to land as far from the
take-off point as possible.
Competitors sprint down a runway (usually coated with the same
rubberized surface as running tracks, crumb
rubber or vulcanized
rubber) and jump as far as they can off of a wooden board
into a pit filled with finely ground gravel or sand. The
distance traveled by a jumper is often referred to as the
“mark,” because it is the distance to which the first mark is
made in the sand. More specifically, a mark is the minimum
distance from the edge of the takeoff board, nearest the landing
pit, to the first indentation made by the competitor. If the
competitor starts the leap with any part of the foot in front of
the board, the jump is declared illegal and no distance is
recorded. At the elite level, a layer of plasticine is
placed immediately in front of the board to detect this
occurrence. Otherwise, an official (similar to a referee) will observe
the jump and make the determination. The competitor can initiate
the jump from any point behind the foul line; however, the
distance measured will always be from that line. Therefore, it
is in the best interest of the competitor to get as close to the
foul line as possible.
The exact format of the competition varies, but generally each
competitor will get a set number of attempts to make his or her
longest jump, and only the longest legal jump counts towards the
results. Generally, competitors will be given three trial jumps
with which to make their best effort. Higher level competitions are
split into two rounds: trials and finals. In competitions
containing a final round, only a select number of competitors are
invited to return for further competition. The number of
competitors chosen to return to the final round is determined prior
to the start of the meet by a committee comprised generally of
coaches and officials. It is standard practice to allow one more
competitor than the number of scoring positions to return to the
final round. For example, if a given meet allows the top eight
competitors to score points, then the top nine competitors will be
selected to compete in the final round. Taking an extra competitor
to the final round helps to allow that athlete to move into a
scoring position if the competitor can improve on his or her best
mark of the competition. Final rounds are viewed as an additional
three jumps, as they do not have any priority to those scored in
the trial round. The competitor with the longest legal jump (from
either the trial or final rounds) at the end of competition is
declared the winner. (For specific rules and regulations in
U.S. Track &
Field see Rule 185 in
Article III of the USATF 2006 Competition
Rules [1]).
There are four main components of the long jump: the approach
run, the last two strides, takeoff, and action in the air and
landing. Speed in the run-up, or approach, and a high leap off the
board are the fundamentals of success. Because speed is such an
important factor of the approach, it is unsurprising that many
sprinters, notably including Carl Lewis, also
compete successfully in the long jump.
The long jump is also notable for two of the longest-standing
world records in any track and field event. In 1935, Jesse Owens set a
long jump world record that was not broken until 1960 by Ralph Boston.
Later, Bob Beamon jumped
8.90 meters (29 feet, 2-1/2 inches) at the 1968 Summer
Olympics, a jump not exceeded until 1991. On August
30 of that year, Mike
Powell of the USA leapt 8.95
meters at the
World Championships in Tokyo. Some jumps over
8.95 meters have been officially recorded (8.99 meters by Mike
Powell himself, 8.96 meters by Ivan Pedroso), but
were not validated since there was either no reliable wind speed
measurement available, or because wind speed exceeded 2.0 m/s. The
current world record for women is held by Galina
Chistyakova of the former Soviet Union who
leapt 7.52 meters in Leningrad in
1988
History
The long jump was one of the events of the original Olympics in
Ancient Greece. The athletes carried a weight in each hand, which
were called halteres.
These weights would be swung forward as the athlete jumped, in
order to increase momentum, and then thrown backwards whilst in
mid-air, so as to help the jumper propel himself further forward.
Most notable in the ancient sport was a man called Chionis, who
in the 656BC Olympics staged a jump which was equal to 7 meters and
5 centimeters (23 feet and 1.5 inches) [2].
The long jump has been part of modern Olympic
competition since the inception of the Games in
1896.
In 1914, Dr. Harry Eaton
Stewart recommended the “running broad jump” as a standardized
track and field event for women [3].
However, it was not until 1928 that women were
allowed to compete in the event at the Olympic level (See
Athletics
- track and field).
The approach
The objective of the approach is to gradually accelerate to a
maximum controlled speed at takeoff. Observing the laws of
Physics, the two most
important factors for the distance traveled by an object are the
angle and velocity at takeoff.
Elite jumpers usually leave the ground at an angle of twenty
degrees or less; therefore, it is more beneficial for a jumper
to focus on the velocity component of the jump. The greater the
velocity, or speed, at takeoff, the higher and longer the
trajectory of the center of mass
will be. The importance of a higher velocity at takeoff is a
major factor in the success rate for many sprinters in this
event.
The length of the approach is generally a precise distance for
each athlete. Approaches can vary between 12 and 19 strides on the
novice and intermediate levels, while at the elite level they are
closer to between 20 and 22 strides. The exact distance and number
of strides in an approach will depend on the individual jumper’s
experience, sprinting technique, and conditioning level.
Consistency in the approach is important as it is the competitor’s
objective to get as close to the front of the takeoff board as
possible without crossing the line with any part of the foot.
Inconsistent approaches are a common problem in the event. As a
result they are generally practiced often by athletes,
approximately 6-8 times per jumping session (see Training
below).
The last two strides
The objective of the last two strides is to effectively prepare
the body for takeoff while conserving as much speed as
possible.
In this phase, the next to last stride from takeoff is known as
the penultimate stride. This is the longer of the last two strides,
where the competitor begins to lower his or her center of gravity
to prepare the body for the vertical impulse. Directly following
the penultimate stride is the final stride, which is markedly
shorter because the body is beginning to raise the center of
gravity in preparation for takeoff.
The last two strides are an extremely important phase of the
jump, as they ultimately determine the velocity with which the
competitor will be entering into the jump.
Takeoff
The objective of the takeoff is to create a vertical impulse
through the athlete’s center of gravity while maintaining balance
and control.
This phase is one of the most technical parts of the long jump.
Jumpers must be conscious to place the foot flat on the ground,
because jumping off either the heels or the toes will have negative
effects on the jump. Taking off from the board heel-first will
cause a breaking effect, which will decrease velocity and put
strain on the joints. Jumping off the toes will decrease
stabilization, putting the leg at risk of buckling or collapsing
from underneath the jumper. While concentrating on foot placement,
the athlete must also work to maintain proper body position,
keeping the torso upright and moving the hips forward and up to
achieve the maximum distance from board contact to foot
release.
There are four main styles of takeoff: the kick style,
double-arm style, sprint takeoff, and the power sprint of bounding
takeoff.
Kick
The kick style takeoff is a style of takeoff where the athlete
actively cycles the leg before a full impulse has been directed
into the board.
Double-arm
The double-arm style of takeoff works by moving both arms in a
vertical direction as the competitor takes off. This produces a
high hip height and a large vertical impulse.
Sprint
The sprint takeoff is the style most widely instructed by
coaching staff. This is a classic single-arm action that resembles
a jumper in full stride. It is an efficient takeoff style for
maintaining velocity through takeoff.
Power sprint or
bounding
The power sprint takeoff, or bounding takeoff, is arguably one
of the most effective styles. Very similar to the sprint style, the
body resembles a sprinter in full stride. However, there is one
major difference. The arm that pushes back on takeoff (the arm on
the side of the takeoff leg) fully extends backward, rather than
remaining at a bent position. This additional extension increases
the impulse at takeoff.
The “correct” style of takeoff will vary from athlete to
athlete.
Action in the air and
landing
The objective of this phase is to counteract the natural forward
rotation of the body from takeoff while maintaining an effective
landing position.
Once a competitor leaves contact with the ground there is
nothing that can be done to alter the flight path of his or her
center of gravity. What ‘’will’’ affect the distance of the jump is
the body position at landing. If a competitor was to leave the
ground without taking any action to prevent forward rotation in the
air, the body would naturally move into a facedown position as the
velocity of the lower half of the body at takeoff is greater than
the upper half of the body due to the contact with the ground. The
three predominant in-the-air techniques used in the long jump in
order of increasing difficulty of execution are the sail, hang, and
hitch-kick.
Sail
The sail technique is one of the most basic long jump techniques
practiced by competitors. After the takeoff phase is complete, the
jumper immediately lifts the legs into a toe-touching position.
This is useful for the novice jumper, as it allows the competitor
to move into the landing position early. The downside of this
technique is that it does not counter the body’s natural tendency
to rotate too far forward.
Hang
The hang technique works by lengthening the body to make it as
efficiently long as possible. Here both the arms and legs are
extended to reach a maximum distance from the hips. This position
is held until after the jumper reaches the apex of the jump, at
which point the athlete will snap the legs forward into a landing
position. This technique helps to diminish the tendency to tumble
forward or lose the extension of the body. Generally the competitor
is encouraged to flex the knees at a 90 degree angle, which enables
the feet to swing with the fastest possible angular momentum when
snapping into the landing position.
Hitch-kick
The hitch-kick technique [4].
The hitch-kick is also known as “cycling” or “running in the
air”. As the name might suggest, this technique relies on a cycling
action of the arms and legs through the air to maintain an upright
body position. This technique takes longer to execute and is
therefore generally reserved for more experienced jumpers.
In-the-air techniques are generally selected by the athlete and
coach during training based on an individual athlete’s skills and
experience.
When landing, it is the primary objective of the competitor to
not fall back in the landing pit. The jump is measured from
the location in which the body contacts the sand closest to the
takeoff point. For this reason many jumpers will work on keeping
their feet in front of the body at a maximum distance from the
hips. Upon landing, competitors will often use their arms in a
sweeping motion to help keep the legs up and the body forward.
Generally a jumper will bend the knees upon contacting the ground
to cushion the impact on the body.
Training
The long jump generally requires training in a variety of areas.
These areas include, but are not limited to, those listed
below.
Jumping
Long Jumpers tend to practice jumping 2-3 times a week.
Approaches, or run-throughs, are repeated sometimes up to 6-8 times
per session.
Over-distance
running
Over-distance running workouts allow
an athlete to work at distances greater than those at which he or
she must compete. For example, having a 100m runner practice by
running 200m repeats on a track. This is especially concentrated on
early in the season when athletes are working on building
endurance.
Typically over-distance running workouts are performed 1-2 times
a week. This is beneficial for building sprint endurance, which
is needed in competitions where the athlete is sprinting down
the runway 3-6 times.
Weight training
During pre-season training and early in the competition season
weight training tends to play a major role. It is customary for a
long jumper to weight train up to 4 times a week, focusing on
higher repetitions with less weight. Weight training in this
fashion will help the athlete to build a solid base of strength
without creating too much bulk muscle.
Plyometrics
Plyometrics,
including running up and down stairs and hurdle bounding, can be
incorporated into workouts, generally roughly twice a week. This
allows an athlete to work on agility and explosiveness.
Bounding
Bounding is any kind of continuous and repetitive jumping or
leaping. Bounding drills usually entail single leg bounding,
double-leg bounding, or some variation of the two. It may also
include box drills or depth jumps. The focus of bounding drills is
usually to spend as little time on the ground as possible; working
on technical accuracy, fluidity, and jumping endurance and
strength.
Flexibility
Flexibility is an
all-too-often forgotten tool for long jumpers. Effective
flexibility works to prevent injury, which can be important for
high impact events such as the long jump.
A common tool in many long jump workouts is the use of
video
taping. This allows the athlete to go back and review their
own progress as well as enabling the athlete to compare their
own footage to that of world-class athletes.
Training style, duration, and intensity will vary immensely from
athlete to athlete based on both the experience and strength of the
athlete as well as on coaching style.
Source: Wikipedia
http://en.wikipedia.org/wiki/Track_and_field
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