Special thanks to Allen Hedrick,
M.A.,C.S.C.S., Soccer Conditioning Coach, U.S. Air Force
Academy, Colorado Springs, CO for giving permission
to AYSO to reproduce his materials. After much investigation
on plyometrics training.
Plyometric training has become a wider accepted
method for training athletes because of the positive
effect it has on athletes performance. A well
designed plyometric training program should improve
the relationship between maximum strength and explosive
power, with resulting improved performance. Despite
the broad acceptance of plyometric training programs
for prepubescent athletes is still questioned. The primary
reason for this is that the maturation and strength
requirements for beginning plyometric training have
not been well investigation. Despite this, children
seem naturally inclined and adaptable to various forms
of running, hopping, stepping, skipping and jumping.
Observation shows the play activities of the
prepubescent to be full of these plyometric-type activities.
Based on this it seems clear that the prepubescent can
safely use plyometrics if the training is well designed
and supervised by a qualified individual. Because of
this, plyometric training can be viewed as a viable
and safe training method for prepubescent athletes.
Training the Prepubescent Athlete
Significant benefits can be gained by the prepubescent
athlete participating in a well designed conditioning
program. In addition, the performance capacities of
the mature athlete depend, to a large degree, upon the
preparation that occurs during the years of growth.
Thus physical training should receive priority
during the time between 8 and 10 years of age. The development
of a variety of physical abilities, including speed,
power, and agility, have been shown to be most trainable
during this period. Because of this, improving
these qualities should be emphasized because they are
the basic criteria for future sports success.
As previously stated, there is little research-based
information upon which reliable conclusions can be made
regarding any necessary prerequisite strength levels
before the safe initiation of plyometric training. While
the ability to squat 1.5 to 2 times body weight is suggested
by some as the level of strength necessary to begin
plyometric training, this is questionable and probably
not intended for a prepubescent population. While strength
is an important consideration, it is only one of the
many factors that must be addressed before beginning
a plyometric training program. Developing a training
program appropriate to the age and biological development
of the athlete is necessary for the training to be safe
Along with adequate strength levels another
key is the use of the proper technique in the execution
of jumping movements. An important element
is proper foot placement, emphasizing a full foot landing.
The foot should absorb the shock of the landing and
roll forward so that the athlete can push off on the
ball of the foot. Landing the high impact forces through
the ankle and knee joints rather than allowing the elasticity
of the muscle to absorb the shock of landing.
Maintaining an upright carriage of the torso is also
essential to avoiding undue stress. Maintaining an upright
posture is directly related to strength levels in the
torso, lower back and abdominal regions.
Proper footwear is also required for safe plyometric
training. A shoe that fully supports the foot and provides
some shock absorption with out being spongy is important.
The training surface used during plyometric activities
is also important. The surface should be firm yet allow
a slight give upon landing. A surface that is too soft
absorbs too much of the impact force and does not allow
the muscle to stretch at a normal magnitude and rate.
A surface that is too soft also inhibits the ability
to react off the training surface, reducing the potential
training effect. In contrast, a surface that is too
hard adds significantly to the stress of the exercise
on the body.