Longjump, Highjump, Triplejump -

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A Philosophy for the Horizontal Jumps
The most important factor in Long Jump and Triple Jump performance is horizontal velocity. In both events, the athlete seeks to convert run-up speed into longest "flight" possible. Technique plays a greater role in the Triple Jump because of the sequence of rapid contacs with the ground. The two horizontal jumps are also expressions of rhythm and power. Rhythm controls the approach speed and transition to jumping. Power (explosiveness) converts speed into flight.

Mechanics of the Long Jump
Horizontal velocity is the overwhelming determinatin of performance in the Long Jump. Vertical force applied at the takeoff contributes only slightly to the overall distance achieved. The speed of the approach and the need to preserve horizontal velocity make it impossible for the athlete to achieve the theoretically optimum angle of projection of approximately 45 degrees. In actuality, the normal takeoff angle is closer to 25 degrees.
The takeoff angle is determined by the approach velocity and by the lowering of the center of mass on the penultimate (or next-to-last) step, which is followed by full extension of the leg at take-off. Vertical impulse is also attained by driving the free leg and opposite arm through the take-off stride. Trying to gain vertical impulse (height) by slowing to gather for the take-off will shorten the length of the jump. Maintaining forward velocity is the critical factor in long jumping, not gaining height.
Forward rotation is created at take-off by eccentric thrust ant the checking of forward momentum by take-off foot. This requires the athlete, while airborne, to counteract rotation in order to achieve an extended landing. The Hang and Hitchkick styles have developed over time as the predominant methods of long jumping. The Hang slows rotation through extension of the limbs away from the body. The Hitchkick counters forward rotation by creating counter rotation through cycling the arms and legs.
As with any projectile, the trajectory of the jumper`s center of mass is established at take-off. Technique is used to counter forward rotation and optimize the jumper`s position relative to his or her center of mass at landing. A landing position with the arms swept to the back, and the head and chest dropped forward, allows the feet to be extended far beyond the center of mass without the jumper falling back into the pit.

Mechanics of the Triple Jump
As its name reveals, the Triple Jump is a series of three consecutive jumps following a fast approach run. The biomechanics of long jumping generally apply to this event, although there are significant differences because horizontal velocity must be preserved over three consecutive jumps. As with the Long Jump, horizontal velocity is the most influential element of performance. Technique, however, plays a far greater role in the Triple Jump.
The take-off angle in the Triple Jump is less than in the Long Jump (approximately 20 degrees) in order to decrease the amount of deceleration upon landing in each phase. The arms and free leg still drive vigorously, but block in the first two phases (hop and step). This action increases vertical reaction off the ground with minimal slowing of horizontal velocity.
A unique feature of the Triple Jump is the action of the landing foot at the end of each phase. A pawing motion of the foot creates a backward velocity of the landing leg, helping maintain forward horizontal velocity of the body.
In the final jump phase, the athlete uses a Hang position to counter rotation. The Hitchkick style requires more air time than is available in the jump phase of the Triple Jump. The landing position in the Triple Jump is similar to the Long Jump, with the hed and chest dropped forward and the arms swept back.

A Philosophy for the Vertical Jumps
The High Jump is an event that combines ballistic strength with speed, expressed through rhythm and body control. The key to success is the efficient transfer of speed into vertical lift off the ground. Rhythm and technique determine how well the athlete achieves this transfer of speed.
The method of high jumping discussed here is known as the Fosbury Flop (named after its originator, the 1968 Olympic champion, Dick Fosbury). The Flop has become the universal method of high jumping. A high jumper must be thaught to be explosive, fluid, controlled, and consistent.

Mechanics and Technique of High Jump
In strict biomechanical terms, the High Jump is a controlled acceleration using centripetal force to put the body in position to convert horizontal speed into vertical velocity, propelling the center of mass over the crossbar. The unique quality of the Flop is that it enables the athlete to fulfill the biomechanical demands of the event precisely. These demands require the execution of skills which can be discussed in terms of three phases of the jump:
1. The Approach Run
2. The Transition and Take-off
3. The Bar Clearance
These Phases are somewhat artificial, however. The High Jump flows from the first step, and each steps is dependent on the one before it.
The Approach Run
The function of the approach run is to generate horizontal and angular velocity (rotation). This is achieved by running a J-shaped approach to the bar. The curved portion of the run-up creates centrifugal force, requiring the athlete to apply counteracting centripetal force. Doing this puts the body in a leaning-away-from-the-bar position, which hinges to an upright position at take-off. This hinge moment creates rotation, allowing the athlete to clear the bar.
The Transition and Take-off
Biomechanically, the transition from approach run to take-off is the most complex portion of the High Jump. During this phase, horizontal velocitiy and angular momentum are converted to accelerate the athlete's body off the ground. The functions of this phase are to put the body in the most affective jumping position and to apply the maximum possible amount of vertical force to the ground. Obviously, the ultimate goal is to raise the center of mass to the greatest possible height with the appropriate amount of rotation around the horizontal axis. The key to an efficient transitioonn and take-off is lowering the center of mass and maintaining good position in the last strides of the approach, while accelerating int the take-off.
This goal is accomplished by holding the last three strides of the run-up on the curve. Then, on the penultimate, or next-to-last step, the center of mass is lowered in preparation for vertical acceleration. The convergence of body position, arm and knee drive, and force applied to the ground project the body into the air toward the bar.
Bar Clearance
Once the athlete is off the ground, the path of his or her center of mass is completely determined. Nonethless, the jumper can maximize body position in relation to the crossbar. Action-reaction priciples enable athletes to help or hinder bar clearance. Ideally, they should keep a relatively flat or slightly arched back over the bar. Keeping the arms and head low elevates the hips, while raising them lowers the hips. The position of the arms affects the speed of rotation over the bar. The legs clear in respond to raising the head and arms once the hips have passed the bar.


Longjump Ivan Pedroso	Highjump Javier Sotomayor	Triplejump Jonathan Edwards	Pole Vault Sergej Bubka