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The
Development of SPEED in Athletics
by
Donald A. Chu, Ph.D., PT, ATC, CSCS |
The
term "speed" can have several meanings that depend on the sport
and framework in which the term is used. This is the first in
a series of articles that will deal with sprint speed development.
Future articles will deal with speed development in directions
other than forward, namely lateral and change-of-direction skills.
The major purpose of these articles is to "bridge the gap" between
science and coaching. They are intended to present the coach
with a set of tools based on scientific fact, that he/she will
be able to implement immediately with the athletes they are
training.
"Sprinting" is the ability to run at maximal or near maximal
efforts for relatively short periods of time. Success in sprinting
is the product of three factors: 1) stride frequency, 2) stride
length; and 3) anaerobic endurance. With proper training and
coaching an athlete can enhance their performance level by improving
any or all of these three areas. The influence of coaching is
most clearly seen in the following areas: 1) technique or mechanics
of running, 2) proper training or metabolic development, 3)
flexibility, 4) strength development, 5) practice sessions including
drills, and 6) race techniques and strategies including breathing
techniques. The coach can greatly influence a sprinter's development
by having an understanding of methods to improve any or all
of these areas.
Two factors to take into account that comprise the elite sprinter
are stride frequency and stride length. Stride frequency (the
ability of the athlete to cycle the legs quickly) is thought
to be largely fiber dependent. Muscle biopsy studies have shown
world class sprinters to universally possess a ratio of up to
90% fast/slow twitch fiber make-up within the gastrocnemius
and quadricep muscle groups. Regardless of fiber make-up, however,
each individual has a potential that can be improved or hampered
depending on the nature of the training imposed on the athlete.
Stride length has been thought to be an offsetting factor to
stride frequency. Some believe that if you can take a longer
stride you might not have to cycle the legs as quickly in order
to win the race. Optimal stride length, then, is also an important
factor in developing the sprinter.
Sprinting speed can be, and is, a "learned skill". Despite the
genetic advantages that one individual might have, physical
ability quickly plateaus out at the top of competitive ladder.
The athlete who has been taught proper motor skills and learned
their lessons well, will be the first to cross the finish line.
Although the skills and techniques of sprinting may be rehearsed
and perfected at slower speeds, the sprinter must be trained
at maximum efforts to insure the learning process is complete.
There is no room for error in the sprinters world.
Speed in sprinting is defined as runs at 95 to 100% of maximal
effort up to 60 meters. This requires the anaerobic (without
oxygen), alactic (without lactate) energy system that can only
be challenged by high intensity work which is performed without
the presence of muscle fatigue. Therefore, these types of training
sessions should occur only when preceded by very low intensity
workouts or 24-36 hours of recovery.
Longer sprinting speed has been defined as running at maximum
speed for 60 seconds. Those sprinters who have stressed the
long term anaerobic system (lactic energy system) will be able
to perform better at distances greater than 60-100m. Michael
Johnson of the USA is an example of this type of athlete.
In the preparation of the sprinter there are many variables
for the coach to attend to, so let us look at the most basic
training components first. Flexibility, or, range-of-motion
is perhaps the best starting point. There are three rules of
training that apply to flexibility; 1) specificity - these exercises
must focus on the joint actions and event demands; 2) overload
- gains in flexibility occur when the limits of existing range
of movement are reached regularly, this will allow new limits
to be set; 3) reversibility - improvements in flexibility will
be lost if regular work is not maintained. Even elite athletes
will see flexibility deteriorate after approximately three days
if some maintenance work is not done.
Drills to improve flexibility fall into two categories; 1) passive
range of motion and 2) dynamic range of motion. The stretching
of muscle tissue is best achieved in either category after the
muscle has been "warmed-up". This means that there has been
an elevation of core temperature in the body, usually achieved
by jogging or moving actively until perspiration has started.
This time frame may be 10-15 minutes of light jogging and movement
drills. After this time, muscle tissue is more pliable and likely
to give when elongated. It is also likely to stay stretched
for a longer period of time. Flexibility work should precede
every workout, and even more importantly, should conclude every
workout. This allows for the removal of fatigue metabolites
as well as maintaining muscle length and reducing tension. It
should be noted that some researchers believe that excessive
flexibility can be detrimental to power development. Therefore,
it is important to know the ranges required for a particular
sport or activity and not to train beyond them for extended
periods of time.
In sprinting, flexibility and elasticity in the gluteals and
hamstrings can benefit the athlete during knee lift and help
to produce a longer stride.
Whereas,
flexibility in the quadriceps is essential for maximizing the
recovery of the leg during the swing phase.
After take-off, the farther the legs can be separated, the elastic
recoil can help in closing the angle at the point of landing,
again helping to maximize stride length.
Upper extremity flexibility is often overlooked. With so much
focus on the hips and legs it is not surprising that this area
may be ignored. However, there is an optimal degree of shoulder
flexion and extension required to match the efforts required
to match the efforts required on the legs.
Table 1 summarizes some of the potential ranges of motion that
will be required of a sprinter at the various joints.
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Table
1 - Flexibility-Optimal Range of Motion
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Degree
of Rotations |
| Joint
|
Swinging
leg
(flexion) |
Supporting
leg
(extension) |
Hip
(trunk-thigh) |
230-235
deg |
140-155
deg |
Knee
(thigh-leg) |
20-30
deg
at amortization |
175-180
deg
at take off |
Foot
(leg-ankle) |
70-85
deg
dorsi-flexion
at amortization |
140-150
deg
plantar-flexion
at take-off |
| Shoulder
|
40
deg (flexion) |
80
deg (extension) |
| Elbow
|
70
deg (flexion) |
90
deg (extension) |
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Given
this information, let us return to the issue of exercises and
drills useful for developing flexibility and range-of-motion
within the athlete. Static or passive stretching techniques
require the individual to assume a position and hold it for
a minimum of 15-20 seconds. This is the time frame required
to stimulate receptors within the tendons known as the golgi
tendon organs (GTOs). Stimulation of the GTOs results in inhibitory
stimuli being sent to the muscles causing them to relax and
elongate. This activity should be repeated several times for
the same muscle group.
The following diagram depicts 99 different static stretching
and flexibility exercises.
The
coach has many options to call upon for the stretching of the
entire body and it's joints. The design of a static stretching
program depends largely upon the amount of time the coach and
athlete are willing to devote to this area. This time can be
a very individual preference in that some athletes will require
or desire to stretch very little and will need more work; and
others will want to spend great amounts of time stretching when
they already have more than acceptable ranges of motion.
In summary, this is the first article in a series that will
deal with speed development. In preparing an athlete to attempt
maximal speed in pursuit of personal and national or international
records we must reject the old adage that "sprinters are born,
not made". Instead, coaches need to examine the best means of
preparing their athletes for competition. The key to running
speed is stride frequency and stride length. These two factors
along with motor learning and training at the proper metabolism
are extremely crucial to the success of both athlete and coach.
This article has attempted to take the first step towards examining
the steps necessary to achieve success. Static stretching serves
as a means of developing suppleness and increasing range of
motion. Various ranges of motion (degrees) during the sprinting
actions have been discussed. This gives the coach some idea
of the optimal ranges required for high speed running. The key
is to apply those most needed stretches to achieve optimal ranges
of the arms, trunk, hips, knees and ankles.
Finally, the next article will cover the concept of warm-up
and dynamic stretching. Although closely related to static stretching,
these topics deserve a discussion related to each area separately.
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