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Using full acceleration and velocity-dependant exercises to enhance power
training
Article · January 2007
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Using full acceleration and velocity-dependant exercises to enhance power training
By
Dr. Daniel Baker,
Strength Coach Brisbane Broncos, Level 3 Strength Coach,
ASCA Master of Strength & Conditioning,
Edith Cowan University, School of Sport & Biomedical Science
Abstract
This article describes full acceleration exercises and velocity-dependant
exercises that can be used to enhance power training. Traditional resistance
training exercises used to build strength, hypertrophy etc (eg. Bench press, chin-
up, squats, deadlifts) are characterized by slow movement speeds (velocity)
when heavy resistances are used, resulting in low power outputs. If lighter
resistances are used in these exercises an effort to increase velocity, then a large
deceleration phase exists in the latter half of the range of movement in an effort
to stop the tendons and muscles being “jerked” at the end range. In this
instance, velocity is reduced and the body is being taught/trained to decelerate,
not accelerate, which is not optimal for enhancing power output. Consequently,
special resistance exercises which entail full acceleration and higher movement
velocities need to be included in programs that have the objective of increasing
power output and acceleration. These exercises include all the Olympic weight-
lifting exercise derivatives as well as throwing and jumping exercises.
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Introduction
What is the difference between strength and power? Strength is defined
as the ability to apply force and/or overcome resistances to movement. It is best
developed by lifting heavy weights for lower repetitions. When lifting heavy
weights in traditional strength exercises (squat, deadlifts, bench presses, chin-
ups etc) the movement speed can be quite slow (Wilson et al, 1989, 1993), which
is not ideal for power development with more experienced athletes (this will still
work to enhance power in less experienced athletes though). But heavy weights
and low reps in the basic exercises are best for maximal strength.
Power is defined as the work done per unit of time (strength x speed) and
it is best developed by use of a more broader range of resistances (Newton &
Kraemer, 1994) ~ however there must be acceleration and high movement speed
(velocity) for power to be fully developed. “True” power training exercises are
exercises that entail acceleration throughout the entire range of movement (eg.
olympic lifts, jump squats, throws, etc) (Baker, 1995). Table 1 provides an
example of some strength exercises and their counterpart power exercise.
Therefore there may appear to be a quandary between the development
of strength and power ~ strength entails heavy weights, typically performed at
slower speeds, whereas power entails acceleration throughout the range of
movement and faster movement speeds. If you try to lift lighter weights more
explosively in a traditional strength training exercise (eg. bench press), then the
lift starts off with acceleration but by half way up in the range of motion, the
muscles will start to decelerate the weight to stop it “jerking” the muscles/tendons
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at the end of the range of motion (Wilson et al., 1989; 1993; Newton et al.,1996;
1997). So instead of teaching/training our body to accelerate, this method
actually teaches it to decelerate! For collision-based sports, it is always good to
remember the Bruce Lee quote – “ donʼt hit the man, hit through the man”, which
implies accelerating through the collision or contact.
This would seem to imply that training for strength and power are or can
be quite separate in terms of programming exercises, resistances and lifting
speeds etc ~ and they are to a large degree for more experienced trainers.
However, lower level athletes readily respond to basic strength training such that
it will also increase their power for the first few years of training. There are two
methods for experienced trainers to utilize to enhance their power training
(Baker, 2005). They are:
1. Use full acceleration exercises so that force output and acceleration continue
through the full range of movement (no deceleration phase at the end of the
range of movement) and there is high velocity during the movement.
2. Alter the kinetics (force profile) of traditional strength training exercises so that
force/acceleration continue further into the range of movement.
This article will focus on the first method of power development as it suits
most athletes who have attained a reasonable strength base, a training age of >
1 year and who are > 15-16 years of age.
Future articles will describe methods of altering barbell kinetics, which suit
more experienced trainers, in greater detail.
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Include full acceleration exercises as power exercises
Performing an exercise whereby acceleration can occur throughout
the entire range of movement (such as a bench throw or jump squat in a Smith
machine, see Photos 1-2, medicine ball throws, power pushups, power cleans
and all the olympic lift variations etc) allows for higher lifting speeds and power
outputs (see Table 2). If athletes attempt to lift light resistances explosively in
traditional exercises such as bench press and squats, large deceleration phases
occur in the second half of the movement, resulting in lower power outputs as
compared to power versions of bench throw and jump squats. Table 2 provides
an example of power output differences between 1 rep max (1RM) weights in
strength exercises as compared to lighter resistances in power-oriented full
acceleration exercises (Baker, 1995). Thus heavy resistance exercises such as
bench press, squat and deadlifts are considered strength exercises whereas
bench throws, jump squats and power cleans are considered power exercises.
Training to maximize power output should entail both heavy
resistance, slower speed exercises for strength development and exercises
that entail higher velocities and acceleration for the entire range of
movement for rapid power development (Newton & Kraemer, 1994). This two-
sided approach should result in the musculature being able to contract both
forcefully and rapidly, the basis of power production. It may merely be the
dosages of each exercise type that varies depending upon the athletes
experience and strength levels, sport requirements, stage of the training year and
so on.
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Initial exercise choices and progressions
After adequate or base levels of body/limb/joint control and stability and
then general strength have been established in an athlete, they may seek to
embrace power-training methods (Baker and Newton, 2005). This initially entails
full acceleration exercises, which rely on high movement velocities to garner high
power outputs.
The initial exercise choices should be simple technique ballistic exercises
such as jumps and throws using bodyweight and light medicine balls,
respectively as resistances. Proper technique and velocity of movement should
be stressed at all times. The athletes have to be able to accelerate but also
decelerate (for the landing or catch) the resistance being used. Simple jump and
“stick the landing”, throw and “stick the catch” exercises may be best for younger
athletes. These can be seen as “go and stop” (pause between reps) power
exercises that teach acceleration and deceleration. So while we are looking to
coach acceleration through the full range of movement, we are also looking to
coach being able to decelerate safely for the landing or catch of the resistance.
After the simple “sticking” variety of these ballistic exercises have been
mastered, then more ballistic “no pause sets” of multiple reps emphasizing the
rapid transition from eccentric to concentric can be introduced. These simple
ballistic exercises are very effective in improving power and sports tasks like
sprinting and jumping in moderately experienced athletes (Wilson et al., 1993;
Lyttle et al., 1996), but are simpler to teach and learn than other power exercises.
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They lay the foundation for effective learning of the more difficult power exercises
that follow.
As the athletes gains technical mastery and adapts to these demands,
more general power oriented exercises such as jump squats and bench throws in
a Smith machine with resistances of 30-45% 1RM can be progressively and
safely introduced (Baker, 1995, 2000, 2001a-c).
The olympic lifting exercises such as power cleans from hang (or at least
some of its components such as top pull, power shrug etc) can also be
introduced at about the same time ~ again technical mastery and velocity should
override the resistance prescription.
So the progression can be seen as:
1. Bodyweight jumps and light resistance throws learning to accelerate and
decelerate (“stick the landing or catch”) progressing to a more dynamic stretch-
shorten cycle version of the same exercises.
2a. Moderate resistance jump squats and bench throws in a Smith machine.
or
2b. Derivative components of the power clean, such as power shrug and top pull
progressing to power clean from hang/boxes.
3. More complex olympic lifting exercises such as power clean from floor, into a
split receiving position and so on.
Once these three basic groups of full acceleration power training
exercises have been mastered, the direction training takes can be more
accurately determined by the strength and conditioning coach.
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With regards to safety and training progressions, I have never had an
injury in jump squats or bench throws (x 50-70 athletes x 2-4/wk per year x 15
years), despite athletes progressing to and regularly using 100-120 kg and 80 kg,
respectively, because the fundamentals of learning to accelerate and
decelerate the resistance safely was coached initially with light
resistances, before progressive intensity increments were made.
Resistances
The important thing to remember with these full acceleration exercises is
that resistance is less important than the velocity. Consequently you do not train
to failure or to some RM level (eg. 10 RM) nor do you do high reps that cause
fatigue related decreases in velocity. The resistance chosen is one that allows
for an “optimal” combination of high movement velocity and some resistance to
movement. There are zones of intensity for power training adaptations that are
similar to the strength training zones of adaptation (Baker, 2001c). Table 3
details these zones for exercises such as bench throws and jump squats ~
however the olympic lifting exercises such as cleans are slightly different, due to
their unique nature.
While those of us that have access to measurement modalities such as
GymAware, which can measure velocity and power easily, for most coaches you
must rely on training generalizations and your experienced eye.
For those coaches, some generalizations upon appropriate resistances
are: -
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1. Certain ballistic power exercises cannot have general rules regarding “optimal”
resistance calculated as a % of any valid 1RM (eg many medicine ball exercises
or bodyweight jumping exercises). The resistance chosen must allow for full
acceleration and high velocity (Newton & Kraemer, 1994). Again, the coach must
use their experienced eye and look for signs of decrements in velocity or
technique when determining resistance. Remember, if you are also performing
heavy resistance training, this ballistic portion of your training need not replicate
the heavy resistance demands, but seek to improve performance through training
acceleration and velocity through the full range of movement. Therefore it is a
general rule to use lighter, rather than heavier resistances, in ballistic power
training.
2. For bench press throws and jump squats, resistances of 50% 1RM have been
show to maximize power output during testing (Baker, 2000, 2001a-c; Baker &
Nance, 1999; Baker et al., 199a, b; Moss et al., 1997). However experience has
shown that the resistances should be lighter during most of the training cycle
(30-45% 1RM). A general rule I use is that the power training resistance will be
about 50% of the corresponding strength exercises resistance for that week. For
example, if the athlete was using 70% 1RM for full squats for their strength-
training portion of their program, then the power-training portion would use 35%
1RM for jump squats. If the bench press resistance was 90% 1RM, then the
bench throw resistance would be about 45% 1RM (the same generalization could
apply to deadlifts and power cleans).
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By using this general rule, you cannot have an athlete “unprepared” for
“heavy” power training resistances, as they will only ever be using half of the
resistance that they can safely handle for strength work in the same week.
3. For power cleans (and olympic lifting exercises), they can only be done
properly at speed, so as long as technique is good, the power clean will entail full
acceleration and high velocity. Recent studies show that resistances of 50-70%
maximize power output during cleans, but that resistances as light as 30% 1RM
may garner similar power outputs (Kawamori et al., 2005). More experienced
athletes may attain maximal power at even higher % of 1RM (eg. 80%-90 1RM,
Kawamori et al., 2005). Hence heavy lifting beyond the capabilities of an
athletes technical capabilities is not warranted in order to increase power output
for these exercises ~ power cleans result in high power outputs across a wide
spectrum of resistances, if technique and velocity are maintained. Technique
and velocity before resistance should be the motto.
Sets and reps.
So how many reps are typically done in power training exercises? The
latest research done on elite athletes shows that when performing jump squats
and bench press throws with typical power training resistances of 30-40% 1RM,
power output drops off on or after 6 reps (Baker and Newton, 2007a). Also if you
precede power training with high rep foundation or hypertrophy training, you will
experience a large decrease (~ 18-25%) in lifting velocity and power output
(Baker and Newton, 2003; 2007b). So if you are performing general power
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training (30-45% 1M), limit yourself to 5-6 reps and do not precede it with high
rep training.
If you are using resistances that maximize power output (maximal power
training zone) during the core power training exercises such as, 45-55% 1RM for
bench throws and jump squats, sets of 2-3 reps may be a better option (with
more sets providing the vehicle of overload). For power cleans @ 50-70+%
1RM, again 2-3 reps may be a better option, though sets of 5 reps can be
performed as long as technique and velocity are maintained.
If you are using lighter external resistances of (eg. < 10 kg) that cannot be
calculated as a % of any valid 1RM in the ballistic exercises such as medicine
ball exercises or jumping exercises (ballistic power training zone or even lighter),
than reps may go to 8-10 (Baker, 2001).
Rest periods
The rest period used for full acceleration power training exercises has
caused some debate with some coaches or scientists recommending 5-7
minutes. This means you may only perform 9-12 sets in an hour and that a
decent power-oriented workout of 14-20 “work sets” would take almost 2 hours or
more! My experience over the last 12 years monitoring power output is that this
recommendation is theoretical nonsense. Having trained athletes (elite, sub-elite
and emerging) day in, day out, week after week, year after year with power
measuring devices monitoring changes in power output between sets, I have
found that a 1.5 minute turnaround between sets is adequate, if the above
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repetition recommendations are adhered to. For example, an athlete doing 3
reps on a bench throw with 50% 1RM can start a new set every 1.5 minutes, with
no decrement in power output. Three reps on power training exercises takes
less than 5 seconds, meaning a work: rest ratio of about 1:15 ~ certainly a long
recovery ratio.
Conclusions
After adequate or base levels of body/limb/joint control and stability and
then general strength have been established in an athlete, they may seek to
embrace power-training methods. This initially entails full acceleration exercises,
which rely on high movement velocities to garner high power outputs. The initial
exercise choices should be simple technique ballistic exercises such as jumps
and throws using bodyweight and light medicine balls, respectively as
resistances. Proper technique and velocity of movement should be stressed at
all times.
As the athletes gains technical mastery and adapts to these demands,
more general power oriented exercises such as jump squats and bench throws in
a Smith machine with resistances of 30-45% 1RM can be progressively and
safely introduced.
The simpler olympic lifting exercise variations such as the power shrug,
top pull, high pull from the hang or boxes etc, can also be introduced at about the
same time ~ again technical mastery and velocity should override the resistance
prescription. Progression through the vast array of olympic lift variations to
12
power cleans from hang, floor, split receiving position etc as well as other olympic
lifting exercises should be guided by the strength & conditioning coaches
perception of the athletes ability to maintain technique and velocity during these
more complex whole body exercises.
Repetitions for power training are generally low so as not to cause a
fatigue related technical breakdown or reduction in velocity. The actual
repetitions prescribed may be related to zones of intensity. If these
recommendations are adhered to then the turnaround between power training
sets may be in the order of 1.5 minutes.
References
Baker D. (1995). Selecting the appropriate exercises and loads for speed-strength development. Strength & Conditioning Coach. 3(2):8-16.
Baker, D. (2000). Comparison of lower body strength and power between national, state and city level rugby league football players. Strength & Conditioning Coach. 8(4):3-7. 2000.
Baker, D. (2001a). Comparison of maximum upper body strength and power between professional and college-aged rugby league football players. J. Strength Cond. Res. 15(1): 30-35.
Baker, D. (2001b). The effects of an in-season of concurrent training on the maintenance of maximal strength and power in professional and college-aged rugby league football players. J. Strength Cond. Res. 15(2): 172-177.
Baker, D. (2001c). A series of studies on the training of high intensity muscle power in rugby league football players. J. Strength Cond. Res. 15(2): 198-209.
13
Baker D. (2003). The acute negative effects of a hypertrophy-oriented training bout upon subsequent upper body power output. J. Strength Cond. Res. 17(3):527-530.
Baker, D. (2005). Combining scientific research into practical methods to increase the effectiveness of maximal power training. @ASCA website. http://www.strengthandconditioning.org
Baker, D. and S. Nance. (1999). The relationship between strength and power in professional rugby league players. J. Strength Cond. Res. 13(3):224-229.
Baker, D and R. U. Newton. (2005). Methods to increase the effectiveness of maximal power training for the upper body. Strength and Condit. J. 27(6):24-32.
Baker, D and R. U. Newton. (2007a). The change in power output across a high repetition set of bench throws and jump squats in highly trained athletes. J. Strength Cond. Res. (in press).
Baker, D and R. U. Newton. (2007b). The deleterious effects of a hypertrophy-oriented German Volume Training workout upon upper body power output. (sent for publication)Baker D, S. Nance and M. Moore. (2001a). The load that maximises the average mechanical power output during explosive bench press throws in highly trained athletes J. Strength Cond. Res. 15(1): 20-24.
Baker D, S. Nance and M. Moore. (2001b). The load that maximises the average mechanical power output during jump squats in power-trained athletes. J. Strength Cond. Res. 15(1):92-97.
Kawamori, N., Crum, A., Blumert, P., Kulik, R., Childers, J., Wood, J., Stone, M., and G. Haff. (2005): Influence of Different Relative Intensities on Power Output During the Hang Power Clean: Identification of the Optimal Load. J. Strength Cond. Res. 19(3):698–708.
Lyttle, A, Wilson, G and K. Ostrowski. (1996). Enhancing performance: Maximal power versus combined weight and plyometrics training. J. Strength Cond. Res. 10(3):173-179.
Moss, B. M., P. E. Refsnes, A. Abildaard, K. Nicolaysen and J. Jensen. (1997). Effects of maximal effort strength training with different loads on dynamic strength, cross-sectional area, load-power and load-velocity relationships. Eur. J. Appl. Physiol. 75:193-199.
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Newton, R., and Kraemer, W. (1994). Developing explosive muscular power: Implications for a mixed methods training strategy. Strength Condit. J. October:20-31.
Newton, R., W, Kraemer, K, Hakkinen, B, Humphries & A, Murphy. (1996). Kinematics, kinetics and muscle activation during explosive upper body movements. J. Appl. Biomech. 12:31-43.
Newton, R., A. Murphy, B. Humphries, G. Wilson, W. Kraemer and K. Hakkinen. (1997). Influence of load and stretch shortening cycle on the kinematics, kinetics and muscle activation that occurs during explosive bench press throws. Eur. J. Appl. Physiol. 75(4). 333-342.
Wilson, G., Elliott, B. and Kerr, G. (1989): Bar path and force profile characteristics for maximal and submaximal loads in the bench press. Int. J. Sport Biomech. 5: 390-402.
Wilson, G., R. Newton, A. Murphy and B. Humphries. (1993). The optimal training load for the development of dynamic athletic performance. Med. Sci. Sports Exerc. 23:1279-1286.
Table 1. Example of exercises categorized as strength or power exercises. If an exercise entails acceleration throughout the entire range of movement, then it is classified as a power training exercise.---------------------------------------------------------------------------------------------------------
Strength Power
Squat Jump squat
Split squat Alternating leg jump squat
Deadlift Power clean/snatch/pull
Bench press Bench throw
Military press Push jerk
Push up Clap push up
---------------------------------------------------------------------------------------------------------
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Table 2. Estimated power output during a 100% 1RM and 100% Pmax effort for
different exercises for a theoretical athlete with a body mass of 75kg. However,
please note that lifting at less than 100% 1RM will result in higher outputs for the
strength exercises, due to faster lifting speeds.
---------------------------------------------------------------------------------------------------
Exercise Mass x Gravity x Height = Work / Time = Power (kg) x 9.81 x m = J / s = W---------------------------------------------------------------------------------------------------Bench press 100 x 9.81 x .4 = 392 / 2 = 196
Bench throw 50 x 9.81 x .6 = 294/ .7 = 420
Full squat 140 (75) x 9.81 x .65 = 1370/2.75 = 499
Jump squat 45 (75) x 9.81 x .85 = 1000/.6 = 1668
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Deadlift 170 (75)* x 9.81 x .5 = 1202 / 3 = 400
Power clean 90 (75) x 9.81 x .85 = 1375/.8 = 1719
---------------------------------------------------------------------------------------------------------All lifts except the bench press also require the lifting of the body mass (75 kg). The barbell mass and the body mass become the system mass and this combined mass is used to calculate power output. Concentric portion of the lift only.---------------------------------------------------------------------------------------------------------
Table 3. Zones of intensity for power training for bench throws and jump squats
and their related strength training counterparts, bench press and squats,
expressed as % 1RM.
--------------------------------------------------------------------------------------------------- Type and / or goal of training of each intensity zone
---------------------------------------------------------------------------------------------------
Power Strength
Zone 1:
< 20% General neural & technical < 50% Gen. muscle & technical
Zone 2:
20-35% Ballistic speed/power 50-70% Hypertrophy / foundation
Zone 3:
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35-45% Basic power training 70-85% Basic strength training
Zone 4:
45-55% Maximal power training 85-100% Maximal strength training
------------------------------------------------------------------------------------------------------------* Percentage of maximum refers to 1RM, maximum resistance.
For strength, 100% = 1RM resistance. For power, 50%1RM equals maximal
power.
------------------------------------------------------------------------------------------------------------
Photos 1 and 2 show the bench throw exercise in a Smith machine. The loss of hand contact with the barbell in Photo 2 allows for full acceleration throughout the entire range of movement, making this exercise more conducive to power training.
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Photo 3. The 1-arm bench throw on an incline bench is a power exercise especially suited for athletes who have to fend off (all collision types of football), punch (boxers/martial artists) or throw (Shot-putt, cricket, baseball).
Photos 4, 5 and 6. The jump squat exercise in a Smith machine is a power
exercise because the loss of foot contact from the floor allows the athlete to
generate both high forces and high speeds late in the movement range. It can
be performed in a parallel (P4 & 5) or split/alternating stance (P6).
19
Photos 7, 8 and 9. The deadlift exercise is a strength-oriented exercise where
heavy resistances can be lifted, but at slower movements speeds.
20
Photos 10, 11 and 12. The power clean (from the hang in this instance) is a
more power-oriented exercise because of the lighter resistance and faster lifting
speeds.
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