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Date: Thu, 15 Feb 1996 12:11:36 -0800
From: staley@west.net (Charles
I. Staley)
With all the recent discussion on lifting and martial arts, I
decided to inflict er, that is, *submit,* this article to the
list, with hopes that it will provide some helpful information.
As always, I remain open to questions and comments
Charles I. Staley, B.Sc, MSS
International Sports Sciences Association
Strength Defined
The Many Faces of Strength
Maximal Strength
Relative Strength
Methods of Strength Development
The Stretch-shortening Cycle (SSC)
Rate of Force Development
Overcoming the Decelerative and Inhibitory
Aspects of Traditional Weight Training
Strengthening the Antagonists and Stabilizers
Ballistic Training
Strength can be loosely defined as the ability to apply musculo-skeletal
force. But for a more precise definition, we must first consider
the various types of strength expression available to athletes.
Strength as a bio-motor ability has many expressions. Since all
motor tasks require force production, all athletes must concern
themselves with developing their strength levels to the utmost.
The following list highlights the various types of strength needed
by athletes involved in combat sports.
Maximal strength (also called absolute strength) is defined as
the amount of musculoskeletal force you can generate for one all-out
effort. Maximal strength can only be demonstrated or tested in
the weight room during the performance of a maximum (1RM) lift.
While only powerlifters need to demonstrate this type of strength
under competitive conditions, martial artists need to develop
high levels of maximal strength as a "foundation" for
subsequent training objectives later in the training cycle.
Whereas maximal strength refers to strength irrespective of bodyweight,
relative strength is a term used to denote an athlete's strength
per unit of bodyweight. It can be used as a modifier for other
categories of strength, such as speed strength or strength endurance.
Thus if two athletes of different bodyweights can squat 275 pounds,
they have equal maximal strength for that lift, but the lighter
athlete has greater relative strength.Similarly, if two athletes
of different bodyweights have a vertical jump of 30 inches, they
have equal absolute speed-strength, but the lighter athlete has
greater relative speed-strength
Sports which have weight classes depend heavily on relative strength,
as do events where the athlete must overcome his or her bodyweight
to accomplish a motor task (i.e., martial arts, long jump, sprinting,
etc.).Further, sports which have aesthetic requirements (figure
skating, gymnastics, and forms competition in martial arts) rely
heavily upon the development of strength without a commensurate
gain in bodyweight.
Strength can be developed either by applying stress to the muscle
cells themselves, or by targeting the nervous system. The former
method is accomplished through "bodybuilding" methods
(repetitions between 6 and 12), and results in strength gains
through an increase in muscle cross-section. The latter is accomplished
through higher intensity training (repetitions between 1 and 5),
where increased strength is the result of improved "intra-muscular
coordination" (the ability to recruit a greater percentage
of the existing motor unit pool).
Athletes who need absolute strength (throwers, football linemen,
etc.) may utilize both methods. First, bodybuilding methods are
used, followed by nervous system training. The result is an increase
in bodyweight and absolute strength.However, as bodyweight increases,
relative strength decreases. Athletes who depend upon relative
strength should use bodybuilding methods sparingly, unless a higher
weight class is desired. Most strength training is characterized
by high intensity (meaning, a high percentage of the athlete's
1RM), low repetition sets, which improve strength through neural
adaptations rather than increases in muscle cross section.
Most human movement is characterized by an eccentric phase immediately
followed by a concentric phase. This muscular action is called
the stretch-shortening cycle, or SSC. Examples include throwing,
jumping, and even walking. During the eccentric phase, the tendons
develop and store potential kinetic energy, similar to a stretched
elastic band. During the concentric phase, this potential kinetic
energy is returned, resulting in greater force output than if
the movement had begun concentrically. In some movements (jumping
rope, for example), the muscle contracts statically, with movement
being provided by the storing and release of elastic energy through
the tendons. Since static muscular activity requires less energy
than concentric activity, the SSC is an "economical"
way of producing force.
The efficiency of the SSC is easily demonstrated: Perform a vertical
jump in a normal manner, where you first crouch, and then jump
upwards as explosively as possible. Next, crouch, but pause for
five seconds, and then jump upward. You'll see that the jump where
the crouch (or eccentric phase) was IMMEDIATELY followed by the
jump was more successful. The key to preserving as much potential
kinetic energy as possible is to switch from eccentric to concentric
as rapidly as possible. This switch is termed "reactive strength"
by some authors.
If you view a videotaped sparring match in slow motion, you'll
see that almost all fighters "cock" their punches, be
it ever so slightly. The best fighters manage to minimize this
preparatory movement, because observant opponents can pick up
on it. (note: sometimes, physical preparation methods must defer
to tactical requirements).
In order to respect the principle of specificity, strength training
methods should reflect the SSC nature of athletic skills. The
best form of resistance training technologies to accomplish this
task are constant resistance, or "free weights," and
variable resistance, which utilize either cams or levers, in an
attempt to "match" the resistance to the strength curve
of the muscle being trained. The former technology is preferred,
at least in the case of advanced athletes, because machines tend
to rob the synergists and stabilizers of adaptive stress.
For combat athletes, maximal strength is a means rather than an
end. In most athletic endeavors, the time available to develop
maximum muscular force is extremely limited- usually only a fraction
of a second. While high levels of maximal strength are a necessary
prerequisite for the development of speed strength, too much time
spent lifting heavy weights at slow speeds, without progressing
to speed strength methods later in the training cycle, results
in slow athletes.
The ability to apply muscular force rapidly is called rate of
force development, or RFD. Bodybuilding methods slightly improve
maximal strength, but have a negligible effect on RFD. Training
with heavy weights will improves absolute strength, but again,
the RFD remains largely unchanged. Only when speed strength methods
(plyometrics, ballistic training, etc.) are used, is the RFD significantly
improved. Absolute strength declines during this period,but this
is an acceptable (and temporary) trade off. However, if absolute
strength is allowed to degrade too much, RFD will suffer. For
this reason, many coaches alternate between maximum strength and
speed strength phases during the competitive period.
Constant resistance (the most popular form of strength training
used by athletes) has one distinct disadvantage: deceleration.
Using the bench press as an example, when your arms near full
extension, the antagonists (lats, biceps, rhomboids, and medial
traps) begin to contract in an effort to decelerate the bar before
it leaves your hands, as a protective mechanism. This is contrary
to your objective, which is to accelerate your arm. There are
at least two ways to address this inherent disadvantage of constant
and variable resistance training: strengthen the antagonists and
stabilizers, and use ballistic training.
For every muscle in the body, there is another muscle that is
capable of opposing its force. This "pairing" mechanism
is how we are able to move with precision of movement and speed.
However, when one part of this pair becomes too strong in relation
to the other, force output capability suffers.
Many athletes often reinforce this inequity every time they train,
thinking they are respecting the principle of specificity by training
only the prime movers (or "agonists"). An example would
be a martial artist who reasons that since the quadriceps muscle
extends the leg during kicking, the quadriceps should receive
the brunt of the training focus. Soon, the hamstrings (which are
the antagonists in kicking movements) become weak in proportion
to the quads, and power output declines. The student understandably
(but incorrectly) concludes that weight training "slows you
down," because for him, it did.
Weak antagonists contract prematurely to oppose the prime movers,
resulting in reduced movement speed. Stronger antagonists are
less sensitive to this protective response- the body "knows"
that they are strong enough to decelerate the limb at the last
possible moment. As an observation, the lats and biceps of elite
level boxers are always well developed.
Waek stabilizers also limit power output.Stabilizers are muscles
which anchor or immobilize one part of the body, allowing another
part (usually the limbs) to exert force. The most important stabilizers
are those of the trunk- the abdominals and trunk extensors. If
the motor cortex detects that it can't stabilize the force provided
by the prime movers, it simply won't allow the prime mover to
contract with full force.
In a recent article, William Kraemer, a professor at Penn State,
used the term "ballistic training" to describe movements
that are "acellerative, of high velocity, and with projection
into free space." Such methods include plyometrics, modified
Olympic lifting, jumping, throwing, and striking movements (such
as punching a heavy bag or kicking a shield).Since ballistic methods
lack a deceleration phase, they are much more coordination-specific
for most athletes. Ballistic training is initiated relatively
late in the training cycle, as it requires significant preparatory
training with lighter resistances to strengthen tendons and ligaments.
Finally, there is an irony when it comes to strength training
for sport: the objective of strength training is NOT increased
strength per se, but improved athletic performance. I would suggest
that sports conditioning coaches keep this in mind as they design
conditioning programs for their athletes.
(Note: This article was adapted from Special Topics in Martial
Arts Conditioning, course text for the International Sports Sciences
Association's Specialist in Martial Arts Conditioning (SMAC) certification
program. For further information, please call (800) 892-ISSA.)
Charles I. Staley, B.Sc., MSS
International Sports Sciences Association
"Where Theory Meets Practice"
Internet: staley@west.net
Phone: 800-892-ISSA