Long jump is a track field event in which athletes
combine speed, strength and agility in attempt to leap as far as possible from
a take-off point. This event has a history in the Ancient Olympic Games and has
been a modern Olympic event for men since the first Olympics in 1896 and for
women since 1948.
Long jump comprises of four phases, which are
- Approach run up
- Take off
- Flight through air
- Landing
In order to achieve maximum distance in the long jump
event, an athlete must have to balance 3 components, that is, speed, technique,
and strength.
The approach run up
The objective of the approach run is for the athlete
to achieve the ideal speed. Rhythm in the approach run is important to ensure
the ideal speed is achieve and accuracy in hitting the take-off broad. It is
important for the athlete to develop a good running rhythm before accuracy is
addressed. The length of the run will depend on the athlete’s age and speed.
When first determining the number of strides in the approach run start by
matching the number of stride with the athlete’s age;
Age
|
Strides
|
Under 11
|
11
|
Under 13
|
13
|
Under 15
|
15
|
Under 17
|
17
|
Over 17
|
21
|
The start of the approach run should be marked and the
athlete should commence the start from a standing start. Some athletes use a
‘walk on start’ or ‘run on start’ that will provide more initial speed but if
not consistent will impact the accuracy of the approach run onto the take-off
broad. The athlete begins the run with a marked forward lean to develop speed
but before they reach the take-off broad, they should be upright. The athlete
should be on the balls of the feet as in sprinting with a natural head
position, the eyes focused beyond the pit and not the take-off broad.
Accuracy of the approach run onto the take-off broad
is established by:
- Determine the take-off foot
- Stand with your back to the jumping pit and the heel of your non take off on the take-off board scratch line
- Run up the runway the required number of strides, let say, 19 and place a marker where the 19th stride falls.
- Place the non-take off foot on the marker and run back towards the broad and take off. The coach should note where the 17th stride lands in relationship to the take-off board.
- If the foot is behind the take-off broad, let say 20 cm, and then move the start marker 20 cm forward. If the foot is beyond the take-off board then move the marker back.
- Repeat the run up and marker adjustment 4 to 5 times to establish a consistent approach run onto the take-off broad
- Once achieved, measure the distance accurately and record it for future use
- It is important to bear in mind that a head or tail wind will affect the run up. A head wind may mean moving the marker slightly forward.
Ideal speed
Dr. Graham-Smith and Professor Lees (2002), have
identified algorithms that will predict an average distance that an athlete
would be expected to jump for a given speed. These algorithms are based on
official approach speeds and distances collected over a period of ten years
from junior and senior championships and Grand Prix events.
- Male - distance = (speed in m/s x 0.95) - 2.23
- Female - distance = (speed in m/s x 0.99) -2.81
The speed, in metres/seconds (m/s), can be determined
by timing the athlete between two markers set at 11 metres and 1 metre from the
take-off board.
The Take-Off
The preparation for the long jump take-off begins in
the later of phase of approach run. The long jumper prepares for take-off by
sinking the hips and then raising the hips into the take-off phase. This
usually results in the next to last stride being longer than normal and the
final stride being up to 25 centimetres shorter than normal running stride. Tit
must be emphasised that the hip sink and stride adjustment all happen in
response to athlete’s postural adjustments in preparation for the take-off. At
take-off ensure the hips are slightly forward the shoulders.
When the take-off foot is placed on the broad, it is
slightly in advance of the jumper’s hips and should strike the board on the mid
line.
The final two contacts in the take-off should be flat,
almost slapping.
and the non-take-off leg, against the braced take off
leg. These movement should be characterised by short radius (blocked), fast
explosive actions.
The head should be carried in a normal position, in
line with spine, and the eyes should be focused forward and slightly up.
The Flight through the Air
Speed and lift generated on the runway and through
take off can result in the feet hitting the sand early and a loss of a distance
in a jump. The cyclic forward movement of the legs and arms, as seen in the
hitch- kick for example, will correct this forward rotation.
The Landing
During the landing, the athlete is aiming to get the
heels as far away from the take-off broad as is possible. The ideal landing
position is shown in the diagram opposite where the dotted line represents the
projected flight path of the body’s centre of gravity. The heels will need to
land just before the projected flight path to ensure the athlete does not fall
back into the sand. As the feet make contact with the sand, press the heels
downwards and contract the hamstrings causing the hips to rise. As the hips
rise twist them to one side and allow the forward momentum to carry the body
past the landing position.
Optimum take off angle
The take-off speed of a male elite long jumper is
about 10.5m/s in a “run through” (take off angle of zero degrees) and 3.5m/s
for a vertical jump (take off angle of 90 degrees). This decrease in speed
means that the optimum angle of take-off is well below 45 degrees. Linthorne et
a (2005) identifies that the optimum take off angle for a world-class long
jumper may be 21.5º ± 3.5º. Research by Lees et al. (1994) identifies that the
optimum take off angle for a world-class male long jumper may be 21º ± 6º.
LONG JUMP STYLES
- The Stride Jump:
In the stride jump style the athlete maintains the
take-off position for as long as possible and only as the athlete comes into
land does the take-off leg join the free leg for a good landing position.
- The Hang Style
On take-off the athlete drops the free leg to the
vertical, which is then joined by the take-off leg. The arms go overhead to
slow down the rotation about the athlete’s centre of gravity. The legs are then
lifted upwards and forwards whilst lower the trunk. The arms swing past the
legs during the landing phase to ensure a good leg shoot.
Following take off the free leg is straightened and
swung back and down as the take-off leg folds up beneath the hips and comes
forward bent. The take-off leg then continues forward, straightening for
landing. The free leg completes its backward swing behind the hip and then
folds up and moves forwards bent, to join the take-off leg ready for landing.
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