Dr Mel Siff and a Supertraining Yahoogroup member going back and forth

<If you hit bounce off the box correctly you will not experience any problems
with the lower back. The bounce needs to be make on the hamstrings and not
directly with your butt. If you perform it correctly you will the hamstrings
and to some extent the gluts will absorb the impact.

If you perform it incorrectly, you will experience some pressure in the
spine. Sitting back on the box places a lot of pressure on the lower back.
If you perform the bounce correctly, this is no more loading on the
spine…maybe even less that sitting back on the box. >

*** It certainly is useful advice to make most of the contact with the back
of the thighs rather than ever sitting with any significant pressure on the
glutes. However, cases have occurred where poorly understood and
technically hazardous bouncing off a box has caused fractures of area such as
the lumbosacral region of the lower spine, while back pain is also not
uncommon among those who use a definite bounce — and that is the problem
with novice users of the box squat. One cannot emphasize Kenny’s advice
strongly enough that the exercise be done with a correct, very light touching
bounce which does not longitudinally impose impact along the spinal column or
cause the spine to lose its lumbar concavity

Remember that the act of sitting down tends to elicit a relaxation of the
lumbar spine and posterior tilting of the pelvis, which leads to flattening
of the lumbar concavity. If you sit down on a box, you have to make very
definite actions to prevent these spinal relaxing processes from happening,
as is constantly stressed by the Westsiders.

<Bouncing off the box provides a greater stretch reflex. Minimize the risk
by performing it correctly and you’ll illicit a greater training effect in
the stretch reflex.

*** Bouncing off the prestretched muscle complex stimulates the myotatic
stretch reflex more strongly if you do not sit on a box at all. Any
superficial contact with the skin that you sit on will tend to diminish the
intensity of this reflex, plus any delay incurred while you are sitting (even
for less than a second) will diminish it further. Advocates of the box
squat do not even advocate “bouncing” off the box, especially under heavy
loading with a weight or a weight and bands combination.

If you wish to retain enough of the stretch reflex in the muscles of the
“posterior chain”, you should not use the box to offer anything more than a
slight brief touch to the backs of the thighs to enhance proprioceptive
awareness of the position at which you wish to commence your upward drive.
You can gain a good awareness of the prestretch in that position by using a
“Romanian” deadlift — i.e., by lowering and raising the bar from upper thigh
to below the knees by pushing your rear end backwards. Bent-knee good
mornings with glutes thrust back (rather than relying solely on hip flexion
or simple “leaning forwards”) will also enhance one’s awareness of that same
prestretch process.

<You should ease into ballistic box squatting. Once you learn to do it
you’ll illicit a greater training effect in the stretch reflex.>

*** See above – ballistic box squatting will not elicit a greater “training
effect in the stretch reflex”. If you are using box squats to enhance
performance in the squat, the reason is not mainly because you are trying to
“train” the stretch reflex, especially since the competition squat has to be
done without a box and methods of acquiring specific neural programmes tend
to be rather specific to the way in which they were learned. Anyway, I am
sure that this is what Kenny is advising – namely not using the box to sit
upon, but to serve as just a gentle warning system to offer tactile contact
so that you know exactly when to begin your upward drive in the squat. In
this way, you will retain the necessary prestretch and manage to execute the
movement explosively.

There are several reasons why one may use some forms of box squatting, but
“training the stretch reflex” is not one of them. However, the main problem
here is more a matter of scientific correctness and differences in phrasing
the advice more accurately. Some of the box squatting and Westside fans out
there might like to list some of their reasons for using box squats with and
without the added effect of bands for those who have never used box squats.

Mel Siff
Denver, USA
Mel Siff Dot Com
Supertraining Twitter Feed

Note the conclusion that the sticking region does not appear to be caused by
worse leverage (“an increase in the moment arm of the weight about the
shoulder or elbow joints”) or by a significant decrease in muscle activity
during this region. The authors suggest that the problem may lie in the
possibility that the sticking region represents a force-reduced transition
zone between the earlier stretch-assisted acceleration-strength phase and the
later mechanically efficient maximum strength region. The use of limited
range elastic band and chain training (e.g. by Louie Simmons and the Westside
team) may play a useful role in attending to this specific deficit in the
transition zone referred to in this paper.

The relevance of analysing the force-time curve in terms of strength
qualities such as starting strength, acceleration-strength, maximal strength,
explosive strength then becomes more obvious, as discussed in Ch 2 of
“Supertraining”. A better understanding of these fundamental biomechanical
factors then enables one to plan one’s training more effectively.

————————

Elliott BC, Wilson GJ, Kerr GK.

A biomechanical analysis of the sticking region in the Bench Press

Medicine & Science in Sports & Exercise. 21(4):450-62, Aug 1989.

The performance of ten elite powerlifters were analyzed in a simulated
competition environment using three-dimensional cinematography and surface
electromyography while bench pressing approximately 80% of maximum, a maximal
load, and an unsuccessful supramaximal attempt.

The resultant moment arm (from the sagittal and transverse planes) of the
weight about the shoulder axis decreased throughout the upward movement of
the bar. The resultant moment arm of the weight about the elbow axis
decreased throughout the initial portion of the ascent of the bar, recording
a minimum value during the sticking region, and subsequently increased
throughout the remainder of the ascent of the bar.

The electromyograms produced by the prime mover muscles (sternal portion of
pectoralis major, anterior deltoid, long head of triceps brachii) achieved
maximal activation at the beginning of the ascent phase of the lift and
maintained this level essentially unchanged throughout the upward movement of
the bar.

The sticking region, therefore, did not appear to be caused by an increase in
the moment arm of the weight about the shoulder or elbow joints or by a
minimization of muscular activity during this region.

A possible mechanism which envisages the sticking region as a force-reduced
transition phase between a strain energy-assisted *acceleration phase* and a
mechanically advantageous *maximum strength* region is postulated.

—————-

Mel Siff
Denver, USA
Mel Siff Dot Com
Supertraining Twitter Feed

For example, cheating allows one to operate in a different way over one’s
strength curve and actually produces a different strength curve to achieve a
certain activity goal. The manufacturers of variable resistance machines
would have you believe that the use of cams, hydraulic systems and levers is
the only way to enable you to adjust to the varying leverages of a given
joint action. However, one can use cheating to take you past a weaker region
and enable you to load the stronger region, if you wish to overload
eccentrically or concentrically in a given region.

Contrary to what so many average personal trainers often believe, cheating is
not necessarily counterproductive or unsafe – it may actually produce
superior results, if one knows how and when to cheat over the full range of
joint action.

Cheating can permit one to produce a very different and more appropriate
’strength’ (torque, power or force) curve to enable one to overcome a load
more competently and safely. Very often, adherents of the slow training
philosophies militate against the power clean or derivates of it, and even
refer to such movements as ‘cheating’ movements which make allegedly
‘unsafe’ use of momentum and ballistic activity.

In fact, this type of ‘cleaning’ movement is a far more efficient way of
lifting a bar from the ground to the chest compared with the crude sort of
deadlift, reverse curl, upright row combination that so many folk use.
There are several other so-called ‘cheating’ movements which offer safer,
stronger and more efficient ways of overcoming a load.

A brief aside — If HIT or ‘Superslow’ methods are indeed ‘better’ than
Olympic and other ballistic methods, can one explain how SIB adherents raise
a heavy bar from the ground to the shoulders? Do they always unload the bar,
slowly raise it with a reverse curl to the shoulders, place it on a rack,
add more weights and only then perform the exercise?)

In other words, the term ‘cheating’ may well have to be redefined.
Bodybuilders know that the term really means using a movement which
deviates from the traditional or classical form in some way such as
swinging the weights or moving parts of the body to assist one in overcoming
’sticking points’. Unfortunately, many other folk believe that cheating is a
breaking of some training law, a serious crime against the body or the unfair
use of some method that is frowned upon by the purists.

In Powerlifting and Olympic Weightlifting, the rules of competition DO
legislate against certain types of ‘cheating’ or illegal lifting techniques,
such as uneven extension of the elbows, not completing the movement, allowing
the bar to stop during a lift, and using series of up-and-down bounces to
complete some lifts.

In the common world of resistance training, no such laws exist, only
guidelines – ’strict’ movements are defined as such, but they are not the
only way of doing any given lift. Variations very soon become the lifeblood
of the trainee who moves out of novice ranks, so cheating is a highly
acceptable technique in the training compendium of anyone who is serious
about progressing.

However, cheating does not necessarily produce better results by allowing one
to use his/her ’strength curve’ more effectively – it may simply be that
cheating allows one to use a heavier load over a certain part of the
movement, especially during the eccentric lowering phase, which is often
implicated in enhanced hypertrophy and strength production (though not so if
used for too long or too frequently). Ballistic forms of ‘cheating’ can
elicit a more powerful myotatic stretch reflex and produce greater muscle
tension with greater potential for enhancing strength and RFD (Rate of Force
Development).

It is really interesting to see how much more can lie in an apparently
simple and time-worn concept such as cheating – no wonder the world of
strength conditioning is so fascinating! There is always something new
lurking under the surface of everything that we often take for granted, even
after years of training and research. Thank goodness we now have the
Internet to allow ideas to be tested and disseminated far more rapidly than
ever before!

Mel Siff
Denver, USA
Mel Siff Dot Com
Supertraining Twitter Feed

The study below shows that even moderate resistance training executed while a
muscle is compressed can produce a greater increase in strength, hypertrophy
and local muscle endurance than if one trains without the muscle being
compressed. Note that the exercise was performed with only 50% of 1RM and
that the compression only amounted to less than one-third of atmospheric
pressure, so it would be interesting to see how the results would change with
greater resistance and somewhat greater levels of compression.

Let us now recall the typical loading used in explosive lifting training
(i.e. with loads of 50-67% of 1RM), which is of the same order of magnitude
as was used in this experiment. Suppose, instead of not wearing supportive
garb, we chose to train regularly with firm wraps, powerlifting suits/vests
or neoprene sleeves. Would this not possibly result in increases in strength
and all those other performance factors?

Maybe all that theoretical advice that supportive apparel is detrimental to
training might be proved to be very wrong indeed — after all, the evidence
quoted is based entirely on theoretical grounds and anecdotes, while the
below study proved experimentally that compression-aided training improves
several fitness and strength qualities of high-level athletes. Maybe wearing
a belt not only enhances proprioceptive sensitivity, confidence and some
“core” stability, but it actually may increase the strength and growth of the
trunk musculature. Similarly, wraps around the thighs, chest and arms may
produce the same effects in those regions. What then about doing
crunches and other abdominal exercises while wearing wraps or a very flexible
corset around the trunk?

Only one way to find out about this theory without waiting for scientists to
take many months and a few years to have their research published – we can
personally try this (moderate) compression training method for a few months
and see what happens. There is nothing to lose and something to gain. We
could try squatting or cleaning with wraps (or neoprene sleeves) around the
thighs and bench pressing with lifting shirt and wraps around the upper arms
- and keep careful records of lifts and limb girths (and skinfolds) to
monitor any changes (and compare them with our usual patterns of change).

Now read the study for yourselves:

—————-

Effects of resistance exercise combined with vascular occlusion on muscle
function in athletes

Yudai Takarada, Yoshiaki Sato & Naokata Ishii

Eur J Appl Physiol (2002) 86: 308-314

The effects of resistance exercise combined with vascular occlusion on muscle
function were investigated in highly trained athletes. Elite rugby players
(n=17) took part in an 8 week study of exercise training of the knee extensor
muscles, in which low-intensity [about 50% of one repetition maximum]
exercise combined with an occlusion pressure of about 200 mmHg (LIO, n=6),
low-intensity exercise without the occlusion (LI, n=6), and no exercise
training (untrained control, n=5) were included. The exercise in the LI
[non-compression] group was of the same intensity and amount as in the LIO
[compression - MCS] group.

1. The LIO [compression] group showed a significantly larger increase in
isokinetic knee extension torque than that in the other two groups at all the
velocities studied.

2. On the other hand, no significant difference was seen between LI
[non-compression] and the control group.

3. In the LIO [compression] group, the cross-sectional area of knee
extensors increased significantly, suggesting that the increase in knee
extension strength was mainly caused by muscle hypertrophy.

4. The dynamic endurance of knee extensors estimated from the decreases in
mechanical work production and peak force after 50 repeated concentric
contractions was also improved after LIO [compression], whereas no
significant change was observed in the LI [non-compression] and control
groups.

The results indicated that low-intensity resistance exercise causes, in
almost fully trained athletes, increases in muscle size, strength and
endurance, when combined with vascular occlusion [compression].

————-

Mel Siff
Denver, USA
Mel Siff Dot Com
Supertraining Twitter Feed

I am interested in whatever information someone might have on depth landings,
such as recommended height, how depth landings impact strength development,
how the Russians used them in training, frequency in training, etc.

Mel Siff’s response was
*** Their main role is in producing high levels of eccentric force, which
seems to be associated with increases in strength and hypertrophy, but only
for a limited time, because their ephemeral and explosive nature is
associated more with neural than muscular changes (depending on how you
amortise or slow down the landing). Russian research has even examined depth
drops from a height of as much as 9ft or more, but this has not shown any
superior increase in “functional strength” or movement speed over
conventional “plyometrics” (discussed in Ch 5 of “Supertraining”). Dr
Zatsiorsky also is not very enthusiastic in his text “Science and Practice of
Strength Training” about the value of depth landings. Russian athletes seem
to rely seldom on this type of training for any significant part of their
training, although many forms of vertical or long jumping (and low
repetition”plyometrics”) are quite regularly used.

If you are contemplating the use of regular landings for bodybuilding or
non-competitive reasons, you are simply increasing the risk of injury unless
your drop heights are no more than about 1 metre (say, about 3 ft), your
number of repetitions is low and your landing technique is exemplary. A far
better way of eccentrically loading the extensors of the knee for increasing
strength and hypertrophy is to do exercises such as heavy squats, dips for
jerks or push presses.

Mel Siff
Denver, USA
Mel Siff Dot Com
Supertraining Twitter Feed

*** Nobody has commented on one issue yet, namely the fact that you struggle
to hang snatch 60kg even though you could power snatch 110kg. My best lifts
would appear to be quite similar to yours, but I never struggled to hang
snatch 100kg without straps. However, on warmer days, sweating of the palms
certainly can make it difficult to grip a bar without chalk, especially if
you are not using a hook grip. It is very
unrealistic to ban the use of chalk AND straps — it is fact that someone
people perspire more than others, plus some athletes have small hands. Is
this the reason why you struggle to hang snatch only 60kg or is it because of
some genuine gripping weakness?

If he is concerned about training specificity, then I trust that his players
are all squatting and power snatching with football cleats on and possible
even with full padded gear on, because executing any plays without that sort
of apparel is very different from doing the same in gym attire.

Even if occasional use of straps or chalk may result in some (unlikely) loss
in gripping strength, American football does not permit holding opposing
players or gripping helmets, so what is his point? If you played in a rugby
scrum where you firmly hold your teammates, I could vaguely appreciate his
dictates, but in American football, there appears to be no logical reasoning
behind his authoritarian manner. Does he offer any scientific or practical
reason why the use of chalk and straps is so detrimental to the conditioning
of a footballer who doesn’t use gripping as a major part of the play? –
Don’t let him tell you that this makes a difference to tackling ability (as
opposed to blocking), because the hand grasping actions involved in snatching
and tackling are radically different.

So far, unless you have a major gripping problem, it would appear as if he is
playing like a military sergeant who commands recruits to clean out the
toilets with a toothbrush, just because that is the way it has always been
and that is the way it always shall be! I prefer all athletes to know and
fully understand the genuine reasons why I am prescribing any training drill.
His “telling” style of leadership (as opposed to “selling” style – see Ch 6
of “Supertraining”) may be appropriate for complete novices, but not for more
experienced athletes.

Mel Siff
Denver, USA
Mel Siff Dot Com
Supertraining Twitter Feed

*** Increase in strength with any exercise depends on your training load. If
you power clean with 25kg every day for weeks, your strength will hardly
increase by much, even if you try to accelerate the load as much as you can
(there is a limit to how much you can increase force in a given exercise with
a given load). What you lose by not doing power cleans depends on what your
training goals are.

Just remember that the power clean as a single exercise involves far more
muscles and joints in stabilising and moving action than any other machine
and most other free weight exercises in the gym — that will tell you
something about its training value. Regarding its safety — as with any
other exercise, be it ballistic, explosive or otherwise, this depends on
technical skill and avoidance of overtraining. Many of us have used this
exercise and numerous other derivatives of the Olympic lifts for decades
without any injury, so, if someone attempts to dissuade you from doing such
movements, ignore the fear-mongering and simply train carefully and
intelligently.

<BTW, how are you supposed to lower the bar in a power clean? The people in
my gym lower it quite quickly and it drops to the floor. I tend to let it
fall onto my thighs then do the reverse of a deadlift. What’s the proper
way? I can’t find any reliable resource on the net.

*** The lowering also depends on your goals. Many weightlifters (using bars
with rubber bumper plates) often drop the bar from quite high up simply to
save energy for the more concentric actions of pulling or jerking. If you
wish to obtain some eccentric training, then, by all means, lower the bar
slowly and even hold it isometrically at different points on the way down for
some isometric and “postural alignment” training. Whichever way you lower
the bar, just do in a manner which approximates what you did to clean the
load — in other words, keep the bar close to the body, don’t round the
lumbar spine and rely on knee and hip flexion to do a great deal of the
lowering from below mid thigh level. Anyhow, it sounds like you are doing
that, so fear not!

<Anyone has any advice on a power clean gaining routine? I’m a
beginner-intermediate, trained for about 4yrs., can squat 100kg x 20. I’m
thinking of making gains in my squats and power cleans.>

*** For a start, you do not need to do high rep back squatting. Nothing
“wrong” with doing occasional high rep sets, but to increase maximal
strength, you need to do many more sets with few reps (2-3) and higher loads
(including explosive power training with 55-70% loads). To make gains in your
power clean, you need to power clean regularly, but make sure that your
technique is efficient and safe — and don’t waste your time with anything m
ore than 3 -5 reps at a time. There are several articles on squat training
in our archives. Incidentally, we cannot judge whether or not your 100kg
squat is “good” or not, because the load which you lift depends on your
bodymass and age.

Mel Siff

Why does it appear as if the wheel has been re-invented? What was wrong with
the former name? Is it because the new generation of bodybuilders have become
more prudish in not wanting to be associated with “stripping” (unlikely!) or
does the “drop set” really offer something entirely distinct from all the
different types of stripping, or Diminishing Load to Failure (DLF), sets?

So, to resolve this issue, let’s have some meticulous definitions of the
different types of “drop” and “stripping” sets. Maybe a more technically
adequate alternative name should be proposed (like DLF or ‘Progressively
Diminishing Load’ sets) instead of either of these terms. Any suggestions?

The terms ‘Compensatory Acceleration Training’ (CAT) term has a nice
technical ring to it, but “drop sets” or “stripping” really do nothing for
the scientific and artistic world of resistance training. Sometimes it is
not surprising that other athletes may think of all of us weights types as
being somewhat sub-intellectual.

Of course, they are making a most unfortunate stereotype of us and those
terms do in some simplistic way describe how an exercise should be done, but
are these the best possible terms to use? What do others think?

Mel Siff

Research shows older men build and lose muscle protein as fast as young men

<http://www.nsca-lift.org/perform/article.asp?ArticleID=10>

Losing muscle and strength late in life may not be an inevitable consequence
of aging, as scientists traditionally have thought, according to a study
undertaken by researchers at the University of Texas Medical Branch at
Galveston, TX. Many believe that the decline of muscle as people grow older -
called sarcopenia – and the accompanying loss of strength and function occur
because muscle proteins begin to break down faster than they can be created
and restored.

The team studied 48 healthy men – the largest group to date examined on this
topic – and tracked the rate at which their bodies created muscle proteins
and the rate of muscle protein breakdown. They found that turnover rates were
similar in younger and older men. That means that other factors must account
for the muscle loss and weakening that come with age. Muscle loss in aging
may be linked to many other potential reasons, including older people’s
eating habits, the body’s ability to use protein from food, and hormonal
changes. Between 1997 and 2000, the researchers recruited 22 healthy seniors
with an average age of 70 to participate in the study. They compared them to
26 younger healthy men with an average age of 28.

In both old and young participants, the balance between synthesis and
breakdown was similar – although the researchers found that muscle protein
both was created and broken down a little faster in older people than in the
young group.

Volpi E et. al. Basal muscle amino acid kinetics and protein synthesis in
healthy young and older men. J of the American Medical Association 286(10):
1206-1212. 2001

———————-

Mel Siff

Previous investigations have reported training-induced increases in EMG
amplitude after concentric isokinetic training. The results of the present
study and those of Komi and Buskirk, however, indicated that concentric
isokinetic strength training did not result in significantly greater EMG
amplitude values. The reason for the discrepancies between the results of the
present investigation and those of others examining EMG responses to
concentric isokinetic training may be a function of differences in the
procedures used to analyze and quantify the EMG signal.

The lack of a significant change in EMG amplitude in the present study (Fig 3
) indicated that increased PT in the trained limb was not associated with
increased neural drive to the vastus lateralis. The reason for the increase
in PT in the absence of increased EMG activity is unknown; however, previous
investigations have provided plausible hypotheses:

(a) changes in neural drive to the other muscles or muscle groups involved in
the performance of leg extension, and

(b) muscle adaptations independent of EMG activity.

Changes in Neural Drive to Other Muscles or Muscle Groups

When performing leg extensions, many muscles in addition to the vastus
lateralis are involved. These muscles include (a) muscles of the stabilizing
muscle groups, (b) muscles of the antagonistic muscle groups, and/or (c) the
other muscles of the quadriceps femoris. Stabilizing muscle groups involved
in leg extension, such as the back, abdominal, shoulder, and arm muscles, are
essential for maximum peak torque production because they stabilize the upper
body and prevent flexion at the trunk .

Rutherford and Jones have suggested that the ability of the quadriceps
femoris to generate torque may be limited by the lack of coordinated
activation of these muscles. These investigators reported that an improvement
in PT of the leg extensors after isometric training did not occur until new
neural pathways that coordinated the actions of stabilizing muscle groups
were established. It was suggested that during muscular training,
coordination of the muscles that aid in the performance of leg extension are
involved in a learning process and that more complex movements may require a
longer learning process. Thus, it is possible that the training in the
present study increased the coordination of the stabilizing muscle groups,
which resulted in increased PT production.

Another group of muscles that may “learn” to aid in the expression of leg
extension torque are the muscles that are antagonistic to the quadriceps
femoris. Recent evidence indicates that the levels of antagonistic
cocontraction are modifiable with training. Carolan and Cafarelli measured
the EMG activity in the vastus lateralis and hamstrings after isometric
training of the leg extensors and reported that there was no change in vastus
lateralis EMG activity, but there was a decrease in hamstring EMG activity. A
training-induced decrease in hamstring coactivation in the present
investigation may have provided less opposing torque to the contracting
quadriceps femoris and resulted in increased PT production.

This hypothesis is not in accordance with the findings of Tyler and Hutton ,
who have suggested that since antagonistic coactivation reduces the neural
drive to the agonists through reciprocal inhibition, a training-induced
reduction in antagonistic coactivation would allow greater activation of
agonists. If the suggestion of Tyler and Hutton is correct, a
training-induced reduction in hamstring coactivation in the present study
would have resulted in greater activation and, therefore, greater EMG
amplitude in the vastus lateralis.

Measurements of EMG activity in the present study were made only for the
vastus lateralis. It is possible that there may have been changes in neural
drive to the other muscles of the quadriceps femoris, which could have
resulted in an increased ability to produce torque. Narici et al attributed
differences in the hypertrophic responses of the individual muscles of the
quadriceps femoris to differences in muscle activation after concentric
isokinetic training at a velocity of 120° per sec. These authors observed
preferential hypertrophy and greater EMG activity in the vastus medialis and
rectus femoris when compared with the vastus lateralis. Thus, there may have
been increased neural activation of the other muscles of the quadriceps
femoris, which resulted in preferential hypertrophy and increased PT
production.

Muscular Adaptations Independent of EMG Activity in the Trained Limb

Hypertrophic Factors:

As individual muscle fibers enlarge, their positions under surface electrodes
are altered. Therefore, it is possible that hypertrophy alone could have
influenced the EMG signal. Garfinkel and Cafarelli, however, hypothesized
that if electrode placement is constant, then the electrodes are detecting
EMG over the same area of muscle membrane and, therefore, hypertrophy would
not alter the EMG.

If the hypothesis of Garfinkel and Cafarelli is correct, hypertrophy of the
vastus lateralis could have occurred in the present study without directly
influencing the amplitude of the EMG signal. In addition to the vastus
lateralis, other muscles involved in leg extension (i.e., stabilizing muscle
groups, rectus femoris, vastus intermedius, vastus medialis, and other
muscles) may have hypertrophied as well.

It is possible that architectural factors that cause or are a result of
hypertrophy of these muscles, yet are independent of muscle activation, may
have contributed to PT production. Such factors include (a) increased
contractile protein content, (b) increased pennation angles, and/or (c)
changes in tendinous attachments.

Garfinkel and Cafarelli examined the EMG responses of the vastus lateralis to
isometric training and reported that there was no change in the EMG activity
but a 28% increase in PT production. It was proposed that the increase in
contractile proteins that accompanies muscle training could result in greater
PT simply because each hypertrophied muscle cell is able to form a greater
number of cross-bridges for any level of activation.

Another architectural factor that is important in the production of PT, yet
is independent of EMG activity, is the pennation angle. Recent studies have
shown that trained or hypertrophied muscles have pennation angles greater
than those in untrained or atrophied muscles. It has been suggested that an
increase in pennation angles would allow attachment of a greater amount of
contractile tissue to the tendon, which may result in increased PT
production.

It is also possible that the increased collagen synthesis that has been
observed during training-induced muscular hypertrophy may alter connective
tissue attachments. Jones and Rutherford have suggested that if new
attachments were made intermediately between sarcomeres in series and the
tendon, the tension would not only be transmitted through sarcomeres in
series, but also through intermediate sarcomeres, thereby, increasing torque
production. Thus, it is possible that muscle hypertrophy, either in the
vastus lateralis or other muscles involved in leg extension, occurred as a
result of the maximal isokinetic training and resulted in increased PT
production that was independent of EMG activity.

Nonhypertrophic Factors

Previous investigations have reported that there may be qualitative changes
in muscle fiber protein expression (i.e., fast fiber type conversions from
Type IIb to Type IIa) as a result of resistance training. Although it is not
known how these changes may affect strength, it is possible that the
intramuscular remodeling could contribute to strength gains in the absence of
changes in the EMG….

———————-

Mel Siff