HIGH JUMP
Over time, the high jump has evolved
from a jump, to a roll, to a flop. The third style, the flop, is the most widely used technique today. Dick Fosbury, using
his knowledge of physics, first developed and implemented the flop because he discovered that the technique, when properly
executed, allows one's center of mass to actually pass beneath the bar. His theory and his now widely accepted technique changed
everything about the jump, making it necessary for jumpers to start from scratch-from the approach to the landing. This chapter
details each aspect of the high jump, beginning with the approach, or run-up.
APPROACH
With its curved approach (or J-approach), the flop poses one of the more difficult problems in all jumping events in track
and field as far as achieving run-up accuracy. Most floppers approach the bar at a 9O-degree angle, which is the ideal angle.
The best way to ensure an approach at this angle is to use the near standard as a measuring point and apply the Pythagorean
theorem (figure 10.1). This method will always place the athlete on a 90 degree angle to the pit, no matter how the pit is
placed on the jumping surface.
The
approach to the bar must be exact and consistent; otherwise, the athlete will have to compensate for any miscalculations by
traveling down the bar, changing the angle of approach, or taking a long last step. These compensations result in suboptimal
jumps.
Using the J-approach offers several advantages over other approaches, including
1. better speed development during the straight line portion of the run,
2. better control of the speed, and
3. improved accuracy to and at the takeoff
point.
I recommend to my athletes that they take a 10-step approach, regardless of which side of
the pit they are running from. The side of the approach is determined by the foot an athlete leaves the ground with; that
is, a left footed jumper approaches from the right side of the pit and vice versa. During the straight portion (or the initial
five steps), the athlete should concentrate on developing controllable velocity and a smooth rhythmical stride pattern.
Consistency, control, and confidence are crucial parts of the first five steps of the approach. The run
should be quick and the center of mass should be over each foot as it lands, with each step being faster than the previous.
There should be a quick acceleration during the initial steps followed by a slight acceleration into a short last step (figure
10.2, a and b).
The final portion of the approach-the last five steps-involves the turn-and-plant
and the curve of the J up to the bar. The inside foot is the first to move inward from the straight line, thereby initiating
the turn (figure 10.2c). The jumper, by running this curve, generates centripetal force and will have to develop an inward
lean to maintain the accelerated speed prior to takeoff (figure 10.2d). A jumper can increase this force by shortening the
turn radius, and increasing the velocity.
The penultimate
step of the approach (in the case of a ten-step approach, the ninth) is slightly longer than any of the other steps. This
longer step allows the athlete to lower the hips to place them in a more powerful position. The tenth and final step (figure
10.2e) should be almost the shortest, up to one foot shorter than the longest step, for the following actions to take place:
1. To allow for a hip rise from the penultimate step to the last step
2.
To bring the trail leg through faster, since it is a shorter lever
3. To place the jumper's center
of mass directly over the takeoff foot sooner
4. To create "quickness" off the ground
Table 10.1 provides a ten-step approach checklist.
PLANT
Once the athlete
has arrived at the takeoff point, the actual plant is the most important part of the jump. It is critical that the athlete's
center of mass is directly over the plant foot and leg at the moment the athlete initiates the lift off the ground. The takeoff
leg must be perpendicular to the surface as the lead leg and both arms drive upward and block at a 90degree angle (figure
10.3a). The center of mass then shifts from the vertical position to over the takeoff point toward the bar (figure 10.3b ).If
the jumper goes beyond the vertical position and starts to lean inward toward the bar during the transition from horizontal
to vertical velocity, the body will crash into the bar on the way up. On the other hand, if the jumper does not maintain the
horizontal momentum that has been developed over the previous nine steps, the athlete will not clear the crossbar.
The plant angle is important to the quickness of the takeoff. The greater the angle, the greater the time it takes for the
center of mass to move over the takeoff foot. Severe plant angles keep the jumper on the takeoff foot for a longer period
of time and require a longradius, free-leg swing.
Severe plant angles are caused by a long last step
or by improper arm action. If both arms are brought back together prior to the jump, the end result will be a plant angle
that places the center of mass behind the takeoff foot. Arm action should be continuous throughout the approach with the outside
arm moving through. The inside arm should "hold" only on the conclusive penultimate step. At no time should both
arms be brought back together.
The free-leg swing and the arm drive must occur simultaneously to
achieve a 90-degree angle at the moment of takeoff. Coordinating these exact positions and stopping them at the exact time
that the plant foot leaves the ground results in the un-weighting of the free leg and arms. This upward drive provides a downward
force that creates an eccentric contraction, resulting in a greater force and velocity. Quickness off the ground is very important;
the jumper who can apply the greatest force in the shortest period of time will achieve success.
TAKEOFF
One of the most
important benefits of the curved run is that it causes the jumper to lean away from the bar. This allows the jumper to maintain
horizontal velocity into the takeoff, but it also allows time to move into a vertical takeoff position. Leaning away from
the bar creates a "hinge moment," which in turn creates horizontal rotation over the bar, accomplished by stopping
the foot while the upper body accelerates (figure 10.3c).
As the bar moves higher, some jumpers change
their velocity or shorten the radius of their curve to enhance their vertical lift. The basic rule for heights under 72 inches
is that the takeoff will occur about an arm's length from the near standard. The distance of the foot plant from the standard
or the cross bar is approximately 45 to 50 inches for heights of 72 inches or higher. This same general rule applies to women
attempting to clear a cross bar over 69 inches.
The takeoff point should be directly out from the
closest standard. Jumpers who take off too close to the bar will not be able to maintain momentum during bar clearance. Consider
the following advantages of taking off just off the standard:
1. The jumper will clear the bar at
the lowest point of the cross bar, where the measurement to determine jumping height is made.
2.
The jumper will land directly on the pit; that is, it is very unlikely that the jumper will miss the pit.
3. The bar has a better chance of staying on if it is hit near the center.
FLIGHT AND CLEARANCE
Once the takeoff has been completed, the most important principle to keep in mind during the airborne
portion of the flight is that the movement of the center of mass will not change from the moment of takeoff until landing
in the pit. The flight path that ensures this physical law is known as the parabolic curve, which means that any movements
made while not grounded-that is, movements made only in the air-will not alter the speed of rotation or the position of the
body in relation to the center of mass. The ideal bar clearance is where the center of mass rises the least while the body
clears the crossbar (figure I0.3d).
Also, having both arms as close to the body and legs as short
as possible will allow for faster rotational speed over the cross bar. The following two points are important to remember
during this phase:
• The jumper must avoid lifting the legs up after takeoff and instead allow
the legs to relax and hang once clearance has been achieved.
• If the jumper's seat is down
and the head and feet are in an up-position, it becomes impossible for the jumper to attain the appropriate layout position.
During the flight or layout position, I like to have the jumper's head to drop straight back for
greater hip height when on top of the crossbar (figure 10.3d). If the head is not in this position and assumes a position
that is sometimes taught (the head looking down the bar to the far standard), it will act as a blocking movement and not allow
for the hips
to rise to their maximum height.
The arms that were used to block at the moment
of takeoff never travel beyond the eyes and ultimately float to the hips at the apex of the flight. During the arch position,
the head should go back and the eyes should focus beyond the pit. The legs are bent at the knees to decrease their length
by rotating outward while the heels are pulled in, thus increasing the speed of rotation over the crossbar. The wider or shorter
the legs can become, the shorter the lever, and thus, the faster the rotation over the bar.
LANDING
The jumper has achieved
the best possible bar clearance when the hips have cleared, when the head is as low as possible, and when the layout position
is completed. At that time, a simple bend of the hips will bring the legs and feet up, and by bringing the chin to the chest,
the body will form into a V (figure 10.3e) and assist in the clearance of the legs. The jumper should
land in the pit on the lower-to-middle back with arms and legs extended to the front (figure 10.3f). The athlete does not
want to land on the base of the neck for obvious reasons.
HIGH
JUMP TRAINING
Most technique-specific high jump training involves drilling various aspects of the approach and takeoff. Table 10.2 features
some sample early-season workouts that use these techniques and provides ideas for additional conditioning work for high jumpers.
Adapting to the Situation
Good athletes
have a way of making you reevaluate how you do things. As a high school coach, I had a young man who qualified for the state
meet all four years; he won the state title once and lost the title on misses another year, clearing seven feet. Throughout
his high school career, he continued to improve, was never injured, and continued to make physical and mental progress in
this event, as well as his other sport, football.
When he departed for college, he signed with an
NCAA Division I school and headed off to conquer more heights. It was a year after he left high school that I also left for
the college ranks as a coach. One year later he contacted me regarding a possible transfer to my school because of a change
in his major. That transfer did in fact take place the following year; however, in the meantime he had suffered compartments
syndrome in both of his legs.
Because of his injury and subsequent surgery, he had to complete a
rehabilitation period before resuming regular training. As we moved into the season, it became evident that the way I had
trained him during his four years in high school was unrealistic now; he couldn't handle the training load we would have liked.
As a result, we both sat down and put together a plan. The plan allowed him to rest more while shifting
the work load to focus on quality efforts as opposed to a second jumping session per week. That second session is when we
did strength work and increased volumes. The end result of adapting our training approach was his recovery from the injury
and taking the national title while tying the NCAA Division III indoor high jump record. This experience showed me the need
for compromise, alternative training, and continual communication with the athlete.
FROM: Coaching Track & Field Successfully by
Mark Guthrie
