Kinetic Energy Accumulation Training
By Christian Thibaudeau
for Elitefts.com
Preview from the author's upcoming book. Christian's work can be found at www.Testosterone.net
We will now discuss a special form of strength training that I call
"kinetic energy accumulation training" (or KEAT). It involves training
methods in which there is an important kinetic energy build-up during
the yielding phase of a movement and the consequent use of this energy
to potentiate the overcoming portion of the exercise. This type of
training has been known under various names: shock training (in Russian
literature), plyometrics (by Western coaches) and powermetrics (a more
recent term by Dr. Mel Siff).
I'd rather use the denomination kinetic energy accumulation training as
it explains the nature and the reason for effectiveness of this type of
exercise. Namely, by increasing the amount of kinetic energy produced
during the yielding phase, and transferred into the execution of the
overcoming phase, you increase power and force production and you
improve the neural, reflex and muscular factors involved in force
production.
Most coaches limit this type of exercise to the classic plyometric
drills (depth jumps of various kinds) and regular jump training. However
many more methods are included in this type of training. Before I
present them and explain the reason for the efficacy you must understand
that KEAT is basically a form of accentuated eccentric training.
However, instead of accentuating the eccentric stress by maximizing
eccentric tension (lowering very heavy loads or lowering moderate loads
slowly) we are going to use a very fast yielding action. The objective
is not to increase eccentric stress, but rather to build-up as much
kinetic and elastic energy as we can. To do so, the yielding action must
be very fast and the coupling time (time between the yielding and
overcoming phase of a movement) must be very short.
The types of exercise that we will include in this category of methods
are:
1. Depth jumps
2. Altitude landing
3. Overspeed eccentrics
Depth jumps
Depth jumping, also known as shock training, has been developed by Yuri
Verkhoshansky in 1977. The objective of this method is to increase
concentric power and force output by stimulating the muscles and
reflexes via a "shock stretching" action preceding the overcoming
portion of the movement. This is accomplished by dropping from a certain
height (0.4m to 0.7m. Heights of up to 1.1m have been used but only by
very advanced athletes) to elicit a powerful stretch activation and
jumping up as high as possible immediately upon landing.
It has been well established in both Eastern and Western studies that
depth jumping, or shock training, can significantly increase power
production and the vertical jump. This is mostly due to these factors:
1. An increase in reactive strength. Reactive strength refers to the
capacity to rapidly switch from an eccentric/yielding action to a
concentric/overcoming action. Lack of reactive strength will lead to a
longer coupling time and consequently a lower force and power production
during the overcoming portion of the movement (Kurz 2001).
2. Neural adaptations. Viitasalo et al. (1998) have found a different
neural response with in athletes doing a lot of jumping and regular
individuals when doing a depth jump: jumpers were able to activate more
motor units during the movement (greater EMG) and plan the motor command
faster (higher and more rapid pre-action EMG). Kyröläinen et al. (1991)
have also found that 16 weeks of depth jump training led to a better
jumping efficiency. Schmidtbleicher (1987 and 1982) found that trained
subjects were better able to use the kinetic energy produced during the
eccentric portion of a depth jump while in untrained subjects this
eccentric period was actually inhibiting instead of potentiating!
Finally, Walshe et al. (1998) concluded that the reason for the
superiority of depth jumping training over regular jumping was due to
"the attainment of a higher active muscle state", meaning that the fast
eccentric portion of the movement increased muscle activation.
3. Structural adaptations. Depth jumps have been reported to cause some
muscle soreness and muscle damage (Horita et al. 1999). This is
understandable since the eccentric force production is very high, albeit
rapid. So this could indicate that depth jumps are a powerful stimulus
to stimulate structural adaptations. Obviously, depth jumps do not lead
to significant hypertrophy. So the nature of the structural adaptations
following depth jumping is not quantitative in nature but rather
qualitative: an improvement of the strength and contractile capacity of
each muscle fibers.
Soviet literature gives the following guidelines when practicing depth
jumps:
1. The joint position upon landing should be as close as possible to
that of an important sport action (Laputin and Oleshko 1982).
2. The amortization phase should be short enough to avoid loosing the
elastic energy produced but long enough to allow for the shock
stretching to occur (Laputin and Oleshko 1982). Research indicates that
the elastic energy from landing is stored for up to 2 seconds. So in
theory you have a window of 2 seconds between the landing and take-off
phase, However to maximize the training effect, you should not spend
more than 1 second on the floor.
3. The height of the drop should be regulated by the preparedness of the
athlete: the heels should not touch the ground during the landing phase,
if they do the height of the drop is too high (Laputin and Oleshko
1982). A height varying from 0.5 to 0.7 appears to be ideal for most
strength and power athletes (Roman 1986).
4. Depth jumps have a very powerful training effect so the volume of
work should be low: no more than 4 sets of 10 repetitions (or 40 total
jumps spread over more sets), 2-3 times per week for advanced athletes
and 3 sets of 5-8 repetitions (or 15-24 total jumps spread over more
sets), 1-2 times per week for lower classes of athletes (Laputin and
Oleshko 1982). The problem with coaches and athletes is that they do
feel that depth jumping is hard: it's not very tiring compared to other
means of training. Because of that they do way too much volume of depth
jumps.
5. Still because of the very powerful training effect of depth jumping,
it is idiotic to perform this type of training systematically throughout
the year. The shock method should be used in blocks of 3-4 weeks with at
least 4 weeks between blocks (Roman 1986). In fact some coaches
recommend no more than 2-3 such blocks per year (Medvedyev 1996) and
that these blocks should only be used when a rapid rise in power and
reactive strength is needed to further performance gains. Remember that
every training method, regardless of how effective it is, will loose
it's effectiveness over time. Shock training is no different. So if you
use it year-round there comes a point where you will get no added
benefits from it. However by using short "shock" blocks you can give a
quick boost to your performance and since you only use depth jumps for a
short period, everytime that you use such a shock training block you
will get the same performance boost.
Altitude landings
A recent paper by David Kerin (2002) concluded that it is the eccentric
portion of a depth jump that actually has the greatest training effect
as far as increasing vertical jump and lower body power. It makes sense
when you think about it. It is during the landing portion that the
eccentric stress is at its highest as all the kinetic energy accumulated
during the fall is transformed into muscle loading. So this can greatly
increase your capacity to break your fall and absorb this kinetic
energy. If you are weak in the eccentric portion of the depth jump what
will happen? The coupling time (time it takes you to switch from
yielding to overcoming) will be very high and the resulting jumping
capacity will be low. The shorter the coupling time is, the higher will
be the subsequent jump. And to reduce coupling time you must increase
eccentric strength and the capacity to absorb the kinetic energy.
Depth jumps obviously do this, but doing only the eccentric portion
(landing) and practicing "sticking the landing" (i.e. immediately
breaking the downward movement as soon as you hit the ground) can
actually be more useful in that regard. And this way you can use higher
drop heights (up to 0.75-1.25m). Once again, the key point is to land in
a position specific to your sport. For example football linemen and
linebackers should stick the landing with the knee bent at approximately
90-110 degrees.
Just like depth jumps, altitude landings have a very powerful training
effect and should only be used for short periods of time and at a very
low volume of work. While they can sometimes be used in the same
training block as depth jumps, I don't recommend it. Rather I like the
following progression:
Block 1 (4 weeks)
Altitude landings
Block 2 (4 weeks)
Low intensity jump training
Block 3 (4 weeks)
Depth jumps
Block 4 (4 weeks)
Low intensity jump training
This progression will ensure for constant and rapid progress in vertical
jumping capacity. You can repeat that 16 weeks cycle three times during
the year for fantastic improvements.
Overspeed eccentrics
This type of exercise could almost be called shock training with weights
and it's the brainchild of powerlifting coach Louie Simmons and is
described in his training videos "Reactive method" and "Special
strengths".
Simmons explains that to take advantage of eccentric training for
maximum strength gains in lifting exercises you should use it (the
eccentric/yielding portion) to accumulate kinetic energy that you will
transform in elastic energy, reflex energy and ultimately a greater
force production in the overcoming portion of the lift.
To do so two things must be present:
1. A fast yielding phase: by lowering the bar or your body faster you
produce more kinetic energy. There is actually some research to back up
this technique, not that the results from the Westside powerlifting crew
doesn't already speak volume for the its efficacy! For example a study
by Farthing and Chilibeck (2003) found that "eccentric fast training is
the most effective for muscle hypertrophy and strength gain". This is in
accordance with the findings of Paddon-Jones et al. (2001) that
following a fast eccentric training program led to a decrease in type I
fibers (from 53.8% to 39.1%) while type IIb fiber percentage increased
(from 5.8% to 12.9%). In contrast, the slow eccentric group did not
experience significant changes in muscle fibre type or muscle torque.
2. A rapid switch between the yielding and overcoming phases. The best
example of this break in the yielding/overcoming chain is the use of the
box squat. When you land on the box you immediately halt the yielding
portion of the movement, converting the kinetic energy into elastic
energy and reflex action.
One doesn't have to use the box squat. You can simply lower the bar as
fast as you can and break it in a heart beat before lifting it
explosively.
Using Jump Stretch elastic bands attached to the bar also have a very
positive effect because the bands will actually try to "blast" the bar
down, bringing it down faster than if only gravity was acting on it.
This is one benefit that you don't get from using chains, chains are
only acting as additional weight, while the elastic bands increase
kinetic energy.