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Although most athletic skills
and events depend upon a variety of physical qualities, speed
strength (also called power) certainly rates among the most
important. Whenever you need to accelerate yourself (as in
running, cycling, swimming, skating, or skiing), an external
object (such as a ball, a barbell, a javelin, or another person),
or both (such as pushing a bobsled or driving through an opposing
lineman in football), your ability to generate force with
speed will be a primary determinant of your success.
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As the duration of the event or skill
becomes reduced, the need for speed strength (I'll abbreviate it
as "SS" from this point on) increases. However, even triathletes
rely heavily upon explosive strength as they sprint to the finish
line. It's not a matter of whether or not you need to develop SS,
but to what degree you need to prioritize it in your training.
SS is also a vital quality during
emergency situations, such as when it becomes necessary to quickly
dodge a car when walking across the street, or duck to avoid being
hit by a stray ball. In fact, SS is the body’s preferred method
of force generation— the last time you had to lift a heavy object
from the floor to a high shelf, did you accelerate the load to make
the task easier, or did you make a concerted effort to lift the
object with a constant speed?!
For bodybuilders, SS training methods
are immensely valuable for their ability to improve intramuscular
coordination (the ability to recruit high threshold motor units),
which has significant payoffs during later training phases utilizing
lower intensity loads. In other words, a two week training phase
emphasizing accelerative training techniques will potentiate the
ability to lift greater loads during a subsequent phase utilizing
more "traditional" bodybuilding lifting technique (i.e., constant
tension, avoiding joint lock-outs, etc).
Strength: the Multi-Faceted Motor Quality
Of course, SS is simply one expression
of force output, and strength as a bio-motor ability has many expressions.
The following list briefly describes the types of strength available
to athletes:
Absolute Strength (maximal
strength)
Absolute strength is defined as the
amount of musculoskeletal force you can generate for one all-out
effort, irrespective of time or bodyweight.
This form of strength can be demonstrated
or tested in the weight room during the performance of a maximal,
single repetition lift. While only powerlifters need to maximize
and demonstrate this type of strength in competition, all athletes
need to develop absolute strength as a foundation for other bio-motor
abilities such as SS, strength endurance, agility, and others.1
For this reason, absolute strength is brought to high levels in
the preparatory period, and then "converted" to more event-specific
forms of strength later in the macrocycle. Absolute strength can
be displayed through three types of muscular actions:
1) Concentric Strength: the
ability to overcome a resistance through muscular contraction, i.e.,
the muscle shortens as it develops tension.
2) Eccentric Strength: displayed
when a muscle lengthens as it yields to a resistance. Eccentric
strength is normally 30-50% greater than concentric strength, meaning
that you can lower significantly more weight in good control than
you can actually lift. This may be the result of increased intra-muscular
friction (a concept not yet validated by science) during the eccentric
portion of a lift. In eccentric muscular encounters with external
resistances, there are two possible scenarios which can occur:2
a) The resistance encountered is less
than one’s maximal isometric strength. In weight training applications,
this applies to any load less than 1RM.
b) The resistance encountered is more
than one’s maximal isometric strength. In weight training applications,
this applies to any load more than 1RM (commonly called "eccentric
training").
3) Static Strength: muscular
contraction which does not cause external movement of the resistance,
either because the athlete has chosen to produce exactly enough
force to prevent the resistance from lowering, but not enough to
lift it; or because the external resistance is immovable. Static
strength is also observed during the momentary pause between the
eccentric and concentric portions of a movement.
Absolute Strength Forms the Basis for Speed
Strength
Despite the current preoccupation
with plyometrics, specialized shoes, and the like, improving absolute
strength remains the most efficient way to improve SS.3
In fact, Romanian strength & periodization
specialist Tudor Bompa suggests that "No visible increments of power
are possible without clear gains in maximal (absolute) strength."4
To appreciate the importance of absolute
strength on SS, imagine a rocket weighing 1000 pounds, with an engine
capable of 1200 pounds of thrust.
This rocket has only 200 pounds of
reserve force to propel itself. The same rocket, when equipped with
an engine rated at 3000 pounds of thrust, will have 2000 pounds
of reserve thrust that can be used for propulsion.
Now back to the gym: a 200 pound man
capable of squatting 250 pounds for a single rep will have a mere
50 pounds of reserve strength available to propel his body upward
during a vertical jump. Contrast this with a 200 pound elite-class
powerlifter capable of squatting 600 pounds. Now we’ve got 400 pounds
of strength reserve available, and all things being equal, will
have a vastly superior vertical jump compared to the novice squatter.
Relative Strength
Whereas absolute strength refers to
strength irrespective of bodyweight, relative strength is a term
used to denote an athlete's strength per unit of bodyweight (his
or her "pound for pound strength"). It can be used as a modifier
for other categories of strength, such as speed strength or strength
endurance. So, if two athletes of different bodyweights can power
clean (a display of SS) 275 pounds, they have equal speed strength
for that lift, but the lighter athlete has greater relative speed
strength.
Athletes who compete in weight-class
events depend heavily on relative strength, as do athletes who must
overcome their bodyweight to accomplish a motor task (i.e., long
jump, sprinting, etc.). Further, sports which have aesthetic requirements
(figure skating, gymnastics, etc.) demand the development of strength
without a commensurate gain in bodyweight.
As a side note, in the World of sport,
lighter athletes have better relative strength than heavier athletes,
whereas the heavier athletes get the nod for absolute strength.
In Olympic weightlifting for example, elite-level athletes in light
weight classes have lifted triple-bodyweight from the floor to an
overhead position. World-class competitors in the superheavyweight
division are unable to lift even double-bodyweight; however, the
absolute poundages they lift are far greater than that of their
lighter peers.
Since strength training targets the
neuro-muscular system, strength can be developed through two very
different means— by applying stress either to the muscular or to
the neural aspect of the system. The former method is usually accomplished
through the application of "bodybuilding" methods (repetitions between
6-12 to exhaustion, using continuous tension techniques), and results
in strength gains through an increase in muscle cross-section. The
latter method employs higher intensity training (repetitions between
1 and 5 using accelerative technique and full recoveries between
sets), and increases in strength are the result of the body's improved
ability to recruit more of its existing motor unit pool.
Contrary to conventional wisdom, athletes
who depend upon relative strength or SS should not completely avoid
bodybuilding methods, which, when used judiciously, can be used
to facilitate recovery between periods of intensive nervous system
training. And, as you might expect, I strongly recommend that bodybuilders
keep an open mind with regards to SS methods as well.
Speed Strength
Now to the topic du jour: SS is defined
as work divided by time, where work is defined as force x distance.
Therefore, SS is defined as force x distance, divided by time. SS
is characterized by three distinct components:
- Starting strength: Defined as the
ability to recruit as many motor units (MU’s) as possible instantaneously
at the start of a movement.4 Common examples
include the lunge in fencing, coming off the line in football,
and the start in short sprints.
- Explosive strength: This quality
refers to acceleration or rate of force development. In other
words, once you’ve recruited a maximal number of MU’s, how long
can you keep them recruited? In his seminars, Dr Fred Hatfield,
co-founder of the International Sports
Sciences Association and the first man to officially squat
1000 pounds, compares starting strength to the flash bulb of a
camera, and explosive strength as a flash that stays on and becomes
brighter and brighter the longer it stays on.
With regards to above distinctions,
different sporting skills and events can be classified as either
starting or explosive strength events, depending on the relative
proportion of speed and strength required. The javelin event in
track and field would be classified as a starting strength event
because the implement is very light, which permits the athlete to
impart a great degree of speed during the throw.
Conversely, the shot is relatively
heavy, which means that less speed can be achieved. This makes the
shot put an explosive strength event. Thus, it logically follows
that starting strength athletes emphasize relatively lighter weightloads
in strength training than do explosive strength athletes.
- Stretch Shortening Cycle (Reactive
Strength): Although traditionally classified as a component of
SS, reactive strength is more accurately thought of as an independent
motor quality.5 It involves the storage of potential
kinetic energy during the eccentric portion of a movement, which
is then converted to actual kinetic energy during the subsequent
concentric phase— much like stretching and releasing an elastic
band.
During many skills (jumping rope,
for example), the working muscles attempt to maintain static contraction,
with force output being provided by the storing and release of elastic
energy through the tendons. Since static muscular activity requires
less energy than dynamic muscular activity, reactive strength is
an extremely energy-efficient way of moving— you can do more work
with less calories. This is why novice exercisers can always be
seen doing exercises in the easiest possible manner, using quick,
choppy movements, whether it’s on the bench press or the stair climber.
Reactive strength is also the method
of choice when someone who is tired and/or weak gets up out of a
chair: instead of simply standing up, they will actually lean back
first, and then quickly reverse this action, springing out of the
chair. If you ask someone to rise out of a chair using pure concentric
movement, it looks very unusual. To appreciate the effect
of reactive strength on force production, perform a vertical jump
in a normal manner, where you first crouch, and then rapidly switch
and jump upwards as explosively as possible.
Next, crouch, but pause for five
seconds (this pause will dissipate most if not all of the stored
potential kinetic energy), and then jump upward. You'll find that
the jump where the crouch (or eccentric phase) was IMMEDIATELY followed
by the jump results in a more successful attempt. The key to preserving
as much potential kinetic energy as possible is to switch from eccentric
to concentric as rapidly as possible.
How Muscles Produce Force
1) MU recruitment (intramuscular coordination):
All muscle fibers are one component of what physiologists call "motor
units." A MU is defined as a motor neuron (or nerve cell) and all
the muscle fibers it innervates or "recruits." Without going into
excruciating detail, there are several essential bits of information
that athletes and coaches should understand about the functioning
of MU’s:
- All the fibers of a MU tend to
have the same characteristics.5 When all the
fibers are type II, the motor unit is said to be a high threshold
or "fast" MU. If the fibers are Type I, it is a low threshold
or "slow" MU. See Table 1
for an in-depth description of fiber types.
- The all or none principle: When
an action potential is sent from the cell body to the muscle fibers,
one of two events will occur. If the action potential is strong
enough, all the fibers of that motor unit will contract maximally.
If the action potential is not strong enough, nothing will happen.
In a nutshell, muscle fibers either contract all the way, or not
at all. When the body needs to apply more force, it simply recruits
more MU’s. Generally, untrained people have limited ability to
recruit high threshold MU’s because they are unfamiliar with high-tension
efforts.
- The size principle: MU’s are recruited
in order of size— small to large. This explains why we can use
the muscle to pick up something light (a pencil) or heavy (a dumbbell).
As resistance increases, the body recruits more MU’s.
2) Intermuscular
coordination: the ability of different muscles to cooperate
during the performance of a motor task. Muscles can function in
several different ways depending on the task at hand. The most fundamental
roles that muscles assume are listed below:
- Prime Mover: The primary muscle
responsible for a movement around a joint at any given point in
time. For example, during the bench press exercise, the pectoralis
major is the biggest and strongest muscle involved, and as such
it provides the most force during most of the exercise.
- Synergist: A synergist is a muscle
which dynamically assists the prime mover. Going back to the bench
press example, the front deltoid muscle and triceps would be considered
synergists in this exercise.
- Stabilizer: Stabilizers are muscles
which anchor or stabilize one part of the body (through static
activity), allowing another part to move. In other words, they
assist the prime mover and synergists through static or "isometric"
muscular contraction. The stabilizer role of muscles can be trained
with exercises conducted in an unstable environment, which might
involve dumbbells, Swiss balls, wobble boards, or other devices
designed for this purpose.
For clarification, be aware that prime
movers, synergists, and stabilizers are not different types of muscles—
they are ways in which muscles perform. A single muscle might be
a prime mover in one situation, and a stabilizer in another situation.
- Agonist/antagonist relationship:
(Not to be confused with the roles described above). For every
muscle in the body, there is another muscle capable of resisting
its force. If this were not the case, controlled human movement
would not be possible. When you throw a punch for example, your
tricep is one of the primary agonists (you can distinguish between
these two terms by remembering that "the agonist is the one inagony"),
as it is the muscle which extends the elbow. The primary antagonist
during punching is the biceps, which acts eccentrically to control
the extension force created by the triceps so that you don’t hyper-extend
your elbow at the end of the movement.
3) Rate Coding: The nervous system
can vary the strength of muscular contraction not only by varying
the number of MU’s recruited, but also by varying the firing rate
of each MU, called rate coding. The tension that a MU develops in
response to a single action potential from the nervous system is
called a "twitch." As the stimulus from the nervous system becomes
stronger and stronger, the twitches per millisecond become more
and more frequent until they begin to overlap, causing greater amounts
of tension to be generated by the muscle fiber. The mechanism behind
rate coding is very similar to the way in which increased vibrational
frequency of a sound increases it’s pitch.
As an example, a muscle comprised
of 100 MU’s would have 100 graded increments available to it. In
addition, each MU can vary it’s force output over about a 10-fold
range by varying its firing rate (e.g., from 10 to 50 impulses per
second). For any set of conditions, the force of contraction is
maximal when all MU’s have been recruited and all are firing at
the optimal rate for force production.
The size of a given muscle may in
part determines the relative role of rate coding to total muscular
force development.6
In small muscles, most MU’s are recruited
at a level of force less than 50% of maximal force capacity.
Forces requiring greater tensions are generated primarily through
rate coding. In large proximal muscles (such as the pectoralis and
lats), the recruitment of additional MUs appears to be the main
mechanism for increasing force development up to 80% of absolute
strength and even higher. In the force range between 80% and 100%
of absolute strength, force is increased almost exclusively by intensification
of the MU firing rate.
Training Methods for Speed Strength
Since SS is comprised of speed and
strength, it becomes important to consider what can be done to improve
these two qualities independently, since an improvement in either
aspect will improve the whole.
"Traditional" Strength Training
Since speed is primarily a genetically-inherited
characteristic of the nervous system, it responds poorly to training,
as compared to strength, which is perhaps the easiest motor quality
to improve. For this reason, and because safer methods should be
considered before more risky ones, the starting point for all athletes
who wish to promote SS is traditional strength training. (I use
the term "traditional" to refer to common weight room exercises
performed in a traditional bodybuilding manner using a variety of
intensities).
Compensatory Acceleration Training
(CAT)
CAT training is a distinct form of
accelerative lifting coined by Dr. Fred Hatfield. It refers to compensatorily
speeding up your movement in such a way that improved leverages
are compensated for. For example, when ascending out of a deep squat
position, mechanical leverage begins to improve once you pass the
"sticking point."
This improving leverage reduces the
tension on the working muscles, and in turn, the training stimulus
is compromised. Deliberately accelerating through this movement
path serves to increase muscular tensions. CAT technique takes time
to master, because the acceleration must continue past the sticking
point, yet end before the antagonist muscles are triggered into
decelerating the movement in an effort to prevent joint hyperextension
or loss of control. This "braking" action would be detrimental to
normal coordination patterns involved with common athletic skills
such as hitting, throwing, jumping, and kicking.
Ballistic Training
William Kraemer, perhaps this country’s
most respected and prolific strength researcher, uses the term "ballistic
training" to describe movements that are "accelerative, of high
velocity, and with projection into free space."7 Ballistic
training involves plyometrics, modified Olympic lifting, jumping,
throwing, and striking movements (such as punching or kicking a
heavy bag).
Kraemer argues that, in traditional
barbell training, a significant portion of the movement path (specifically,
the end of the concentric phase) is spent decelerating the bar—
a protective measure assumed by the antagonists to maintain joint
integrity (in upper body movements such as bench pressing), or to
prevent the athlete from leaving the ground in exercises such as
the squat.
If Kraemer’s contention is correct,
one would choose to gradually reduce the volume of traditional barbell
drills as the training cycle progresses, in favor of ballistic exercises
which lack this deceleration phase, making them easier to learn
and much more coordination-specific for most athletes.
The modified Olympic lifts
The sport of Olympic weightlifting
(sometimes called "weightlifting") contests two separate lifts:
the snatch, where the barbell is grasped with a wide grip, and explosively
pulled to an overhead position in a single movement; and the clean
and jerk, where the barbell is grasped with a narrower grip, "cleaned"
to the shoulders, and finally "jerked" to an overhead position.
Competitive lifters reach very deep
squat positions as they struggle to get under ponderous weights
prior to achieving the overhead position. But when slightly lighter
weights are used, the lifter can manage to get under the weight
without going below parallel, meaning that the top of the thighs
never goes past the point of being parallel to the floor.
When a lifter can accomplish this,
the lift is called a power clean (or power snatch). The term "power"
indicates that the load was not maximal, since the lifter didn't
have to squat to rock bottom to get under it. Thus, a power clean
has less of a force component and more of a speed component than
a competitive "squat clean."
Arthur Dreshler, MSS, author of The
Weightlifting Encyclopedia, eloquently describes the benefits
of Olympic lifting and its derivatives for athletes:8
1) Olympic lifts teach an athlete
how to explode (to activate a maximum number of motor units rapidly
and simultaneously).
2) Olympic lifts teach the ability
to apply force with his or her muscle groups in the proper sequence
(i.e., from the center of the body to the extremities). This is
a valuable technical lesson for any athlete who needs to impart
force to another person or object.
3) Olympic lifts teach how to accelerate
objects (including other people) under varying degrees of resistance.
4) Olympic lifts teach how to effectively
receive forces from another moving body.
5) The actual movements performed
while executing the Olympic lifts are among the most common and
fundamental in sport.
6) The Olympic lifts are commonly
used to measure an athlete's force output capabilities.
If you are unfamiliar with the Olympic
lifts and their derivatives. I strongly suggest that you find either
an ISSA-Certified Specialist
in Sports Conditioning, or a USA
Weightlifting Certified Coach in your area who can assist
you with these exercises. These lifts, though not beyond the capabilities
of most athletes, are more complex than the majority of strength
training exercises.
Plyometric Training
Although "plyos" are overused by many
athletes in their quest for the "magic pill" solution to their training
problems, plyometric drills performed with bodyweight, weighted
jackets, light resistances such as medicine balls, logs, sand sacks
and gymnastic equipment can be a valuable component of a SS development
program.
Plyometric training programs must
be designed with sufficient recovery periods to ensure that fatigue
does not take the "elasticity" out of the athlete’s movements, since
it is this repeated elastic neuromuscular control of impact which
provides the training effect.
Testing Your Speed Strength: The Max Jones
Quadrathlon
Few athletes are aware of this unique
and very useful testing implement created by the English track &
field coach of the same name. The MJQ can be used to regularly monitor
your level of speed strength, and can also used as a fun competition
several times a year.
This test is very easy to administer
(you’ll need to do this at your local high school or college track)
and involves only a tape measure and a stop-watch. One note of caution,
however: The four test drills, although relatively simple, will
take a toll on your body (particularly your hip flexors) if you
have never done them before, or if it’s been years since you’ve
done them. If you fall into this category, I strongly suggest you
practice these drills for before going at them "full bore." Start
with very low volume (just a few repetitions of each drill) and
progress gradually over a series of 4-6 sessions.
The test drills are as follows:
Three Jumps: Feet together,
hop three times and land in a long jump pit. Measure from your starting
position to the closest disturbance of the sand where you landed.
Standing Long Jump: Standing
at the edge of a long jump pit, with toes slightly over the edge
of the board, perform a standing long jump into the pit. Measure
from the lip of the board to the closest disturbance of the sand
where you landed.
Thirty Meter Sprint: Using
starting blocks (you may also have a partner place his or her foot
behind your lead foot to simulate a block), start on the command
of a timer at the finish line. The timer starts the watch when your
back foot makes contact with the ground on the first step, and stops
it when you break the finish line.
16lb Overhead Shot: Standing
on top of a shot put stopboard (your back to the pit), dip down
(much like the preparatory crouch for a vertical jump), swing the
shot between the legs, and then extend and throw the shot overhead
backwards. It is not necessary to remain on the stopboard. Measure
from the lip of the stopboard to the first point of impact.
Please see Table 2
for the quadrathlon scoring tables. Simply convert your scores into
the numerical scores provided, and total for your MJQ rating.
A Periodized Training Program for
SS Development: The Rule of Thirds
Since fatigue is specific to the motor
quality being trained, when microcycles with different objectives
and varying demands follow each other, it promotes enhanced recovery,
allows for maintenance of maximal strength and body composition
during periods devoted to SS (and vice versa), and protects against
"overuse" types of injury. The "rule of thirds" is a planning concept
which partitions each mesocycle into thirds— the first two thirds
are spent training the targeted motor ability; the final third is
spent training a complementary motor ability to provide recovery
and balance to the program.
In this program, maximal strength
is the targeted motor ability for the first six weeks, while SS
is the focus of the final six weeks.
Note: Before initiating this training
program, complete the MJQ and record your score. At the completion
of the program, re-take the quadrathlon to assess the effects of
the training.
Citius, Altius, Fortius!
Click Here For A Periodized Training
Cycle for SS Development
References
1) Hatfield, F.C.
(Ed.)(1998). Fitness: The Complete Guide. Santa Barbara, CA: International
Sports Sciences Association.
2) Dick, F.W. (1997). Sports Training
Principles. London: A&C Black.
3, 5) Komi, P.V., (Ed.) (1992) Strength
and Power in Sport. London: Blackwell Scientific Publications
4) Bompa, T. O. (1993). Periodization
of Strength. Toronto: Veritas Publishing, Inc.
5) Hatfield, F.C. (1989). Power:
A Scientific Approach. Chicago: Contemporary Books.
6) Zatsiorsky, V.M. (1995). Science
and Practice of Strength Training. Champaign: Human Kinetics Publishers.
7) Kraemer, W.J., & Newton,
R.U. Muscle Power. Muscular Development, March, 1995
8) Drechsler, A. (1998). The Weightlifting
Encyclopedia. Flushing, NY: A is A Communications.
9) Dunn, G.D., & McGill, K.
(1994). The Throws Manual (2nd. Ed.), Mountain View, CA: Tafnews
Press