Youth Track and Field Instructional DVD's Training for Track and Field: Jumping Events Custom Track Car Window Decals
|
Coaching
the High Jumper
Dynamics
of High Jumping The straddle technique was the most popular until Dick Fosbury won the 1968 Olympics in what was to be called the Fosbury Flop. The flop has become the most popular technique for several reasons. In order to clear the bar with the straddle technique, the jumper must raise his center gravity 2" over the height of the bar. With the flop technique, the jumper needs only to raise his center gravity by 1/2" over the height of the bar. The flopper can approach the bar at a much faster speed than can the straddler. The flop technique is easier to learn for a youngster. The
Straddle Technique In the straddle, the athlete should approach the bar from a 20° to 35° angle at maximum controlled speed. Approaching at this angle will allow the jumper to plant the take-off foot closer to the bar. The number of strides taken in the approach to the bar should be from 7 to 9. The first step of the approach is always with the take off foot. The jumper approaches the bar in a direct line with the angle of approach. The approach is smooth and relaxed with the jumper gradually building to maximum controlled speed. The last three steps of the approach should be long, long and short. The head will be held up, the shoulders squared, and the eyes will be focused on the bar. The arms are carried in the normal sprinting action until the final three steps when they prepare to execute a double arm swing at take-off. On the third stride before take-off, the jumper lowers the center of graivity by flexing the take-off leg and extending the arms downward. The shoulders are drawn forward. On the second to last stride the arms are dropped behind the body, the hips are lowered, and the jumper leans backward. The final stride is shorter than the previous two strides so that his center of gravity can move back over the take-off foot and thrust the jumper into the air. The foot plant is a heel-ball-toe rocker step. The arms swing simultaneously upward in a double arm swing and are blocked out as the hands reach chin level. The provides for greater force on the take-off. The swing of the free leg begins bent, with the thigh and knee leading. It is followed by a whip-like action of the foreleg as it straightens before the leg reaches a horizontal position. Over the Bar As the jumper leaves the ground, the swing of the lead leg and the rotation of the take-off foot will cause the body to begin rotating around its longitudinal axis. After the arms have been clocked out, the right arm will continue upward as the left arm stays bent at the elbows and close to the body. The lead leg will remain straight as it reaches bar height while the take-off leg is brought up, under the bar, flexed. When the jumper is over the bar, the lead leg should be forcefully extended upward in a counter-clockwise motion, leading with the elbow. This will cause an opposite reaction in the trail leg and it will rise to clear the bar. The left arm stays close to the body throughout the clearance. The
Flop Technique In the flop, the approach is approximately 60-70% of the total jump. Because of this, a great deal of practice time needs to be spent on perfecting it. The most often used style of approach in the flop is the J-approach. In this approach, the jumper will take an 8 to 10 stride approach to the bar at a 90° angle. 5 steps will be directly at the bar and 5 steps will be turning a curved path, parallel to the bar. The approach is begun for a left footed jumper by running is a straight line toward a point approximately 15 feet to the right of the right standard. The first 5 steps are used to build speed in a fast but relaxed manner. In the final 5 strides the jumper begins to run a slight curve toward the right hand standard. The running of the curve will build centrifugal force which will prevent the athlete from leaning into the bar at take-off and will also allow him to maintain his speed at takeoff, involving the stretch-reflex mechanism. Take-Off The second and third step from take-off are lengthened to lower the jumper's center of gravity so that on the final stride can be shortened, bringing the center of gravity back over the take-off leg. The take-off foot is planted flat footed and parallel to the cross bar in line with the right-hand standard. It is very difficult to rotate the body if the take-off foot is pointing toward the bar. On take-off, the jumper rocks onto the toes as the free leg and arm are driven up and away from the cross bar at a point in line with the left-hand standard. This develops rotation. Arms are carried naturally throughout the jump. A double arm swing should not be used if at all possible as it will inhibit approach and take-off speed. However, for the slower flopper and the athlete of average ability, a double arm swing is probably more beneficial as it promotes vertical angular momentum because of the blocking out of the arms at take-off. Over the Bar If the take-off has been properly executed, the jumper will be in position to clear the bar. The knees will be slightly spread with the heels together. The head will be turned to the inside with the eyes looking over the shoulder and at the cross bar. The arms will come alongside the body. As the jumper reaches height on top of the bar, the jumper should straighten the back leg and tuck the chin in to the chest. This will cause the legs to rise. The feet will be extended out and up. The landing is executed by landing on the upper back area, not the neck. Share |
|