Turning Negatives Into Positives
Eccentric training is not often emphasized in
CrossFit workouts. And yet it’s integral to producing muscles that perform to
their utmost.
BOB LEFAVI, PH.D. CSCS, USAWOCT
10, 2016
When those butterflies
reach up into your throat, what’s your focus? Our guess is that you’re
concentrating not just on the required movements but also on performing them as
fast as you possibly can. Let’s face it, all things being equal, speed wins.
Whether the WOD is an AMRAP (as many rounds/reps as possible in a certain time
period), an RFT (rounds for time) or even an EMOM (every minute on the minute),
speed of movement means efficiency, less work, more rest and, ultimately,
success.
To be fast, CrossFitters
learn and adapt. And the primary way we learn to increase speed of movement and
efficiency is to reduce unnecessary movements, thereby conserving energy. What
are unnecessary movements? They are the lowering/negative phases of the
movements, which at the level of the muscle are called “eccentric” actions. And
therein lies a potential problem.
Types of Muscle
Contractions
Biologically, a muscle
contraction is simply “an attempt to shorten” a muscle, which causes movement
at a joint because the shortening muscle pulls on bones. Too often, athletes
and coaches assume that a contraction necessarily entails a shortening of the
muscle. It does not. Recall that there are three general types of muscle
contractions:
1. A concentric
contraction occurs when the active muscle produces a force greater than the
resistance it is opposing. In that case, the “attempt” is successful; the
muscle is capable of overcoming the resistance, so it shortens and creates
movement at the joint.
2. An eccentric
contraction is one in which the active muscle does not produce sufficient force
to overcome the resistance. Therefore, the attempt to shorten is unsuccessful,
and the muscle lengthens against the resistance.
3. An isometric
contraction is one in which the amount of force produced by the muscle equals
the resistance, so no movement occurs. Think of your hands against the floor in
a plank or your deltoids holding a bar in overhead lunges.
It’s also important to
understand that we can’t look at joint movements to define what is happening at
the level of the muscle; contractions and joint movements are two different
things altogether.
For example, if you look
at a standard biceps curl, you would be correct to say that in a successful
lift, the biceps are contracting concentrically. In that case, the triceps are
allowing the movement by relaxing. However, if I add 100 pounds to your curl at
the top of the movement and you can’t hold it, you’ll begin to lower the bar
even though you’re fighting with all your might to curl it back up. Your biceps
are contracting eccentrically, but — and this is important — your triceps are
not contracting concentrically, even though the joint action is elbow extension
(which is normally caused by concentric triceps contraction).
Further, when it comes to
eccentric actions, keep in mind that you can intentionally create an eccentric
contraction. For instance, in a front squat, you can and often do purposefully
control your descent. As you descend, your quadriceps contract eccentrically
against the resistance. In a submaximal front squat, your quadriceps can
overcome the resistance (they have sufficient force to cause a concentric
contraction, which they will perform on the way up), but you consciously
control the descent by applying only the right amount of quadriceps force in
order to descend at the appropriate speed.
The Importance of
Eccentric Contractions
And again, speed is what’s
at issue here. Often, in a WOD, we focus on speed, which means we perform
explosive concentric contractions while minimizing time in the
lengthening/negative phase. Eccentric work gets cut out of the mix.
For instance, in “Randy”
(75 snatches for time), do you consciously lower the bar with the same effort
and control with which you pulled it overhead? No. In “Grace” (30
clean-and-jerks for time), do you bring the bar back down to the rack position
and then descend as you ascended? No. You descend as fast as you can, often
coming close to simply dropping the bar. Controlling the negative portion of
the lift would take more time and energy.
The problem is, eccentric
adaptations are required for muscles to develop fully and comprehensively. In
fact, eccentric training is so important to athletic performance that there are
now companies designing what are called “accentuated-eccentric load” machines.
This equipment increases the weight when an athlete gets to the eccentric
portion of the movement.
Here are some reasons we
need eccentric work to be fully prepared functional athletes.
Strength Gains
You’re stronger in the
eccentric part of any lift. In fact, studies show that you’re roughly 1.5 to
1.75 times stronger in the eccentric portion of a lift than the concentric
portion. Avoiding the eccentric portion of the lift means missing out on strength
adaptations our bodies would make by encountering loads we’re capable of
resisting in the negative phase but which we can’t overcome in the positive
phase.
Muscle Size
Eccentric training creates
greater intramuscular friction between muscle microfilaments (actin and
myosin). This friction brings about damage and subsequent repair, and that
repair means growth in muscle size.
Tendon Strength
Strength in connective
tissue is enhanced by eccentric actions much more than by concentric or
isometric work. Stronger connective tissue reduces risk of injury and assists
in stabilizing joints.
Range of Motion
Eccentric loading with
heavy weight has been shown to improve flexibility. The intramuscular friction
from the negative movement promotes not only greater muscle size but also
increased muscle fiber length, and longer muscles can move through a greater
range of motion. One study, published in 2004 in the Journal of Athletic
Training, found that eccentric training could improve joint mobility by 20
percent or more.
More Power, Earlier
Because eccentric work can
handle heavier loads, muscles working eccentrically call on more type II muscle
fibers. These fibers, also called fast-twitch, produce more force earlier in
the movement. The more you train these fibers, the more they grow, ultimately
allowing for more power earlier in your lifts.
Training Eccentrically
A good box ensures its
athletes do not become WOD-only athletes. One criticism of CrossFit is that it
tests strength, power, endurance and agility without building them. That’s why
athletes really need to work at the MOD (movement of the day; sometimes also
called “skill work”).
The MOD should be where
strength and technique are built. This is also where eccentric training should
be standardized. Sure, some of the descent on a wall ball during a WOD will be
a ballistic drop, but that should only be made possible by practicing a good
slow-speed squat that incorporates controlled eccentric and concentric
contractions. The focus of a MOD ought to be on building physiological factors
that can be tested in a WOD. Eccentric or negative training must be a regular
part of that training.
Techniques
Eccentric-Only
With eccentric-only
training, begin the movement at the point at which the concentric portion of
the prime movers (the muscles primarily involved in the lift) ends. So, in the
case of a shoulder press, you start the movement from the lockout position, get
under it and slowly lower the weight. Remember that you can lower more weight
than you can raise, so (after a good warm-up), don’t hesitate to challenge
yourself.
Eccentric-only training
can be quite metabolically costly. Prepare to be taxed. Keep the volume low and
focus on two to three sets of three to four of 110 to 120 percent of your
maximum.
Accentuated-Eccentric
Training
Try this. In a squat,
ascend (or execute the concentric phase) at normal speed and then descend twice
as slow as you ascended. Concentrate on counting at a normal pace, being sure
to be consistent.
Once you’ve mastered that,
try a set or two at three times as slow on the way down. The optimal rate is
1:4 (one second up, four seconds down). This will take some real stability and
stress your technique, but in the end, it will improve your mechanics, range of
motion and muscle strength. That increased strength will translate into power
during a WOD. Here, because you are working with submaximal loads, your volume
can be a bit higher; try four to five sets of six to 10 reps at 70 to 80
percent of your maximum.
Partner-Assisted
In partner-assisted
eccentric training, often referred to in globo gyms as “negatives,” you will
use loads above your maximum. Your partner can assist by helping you get
positioned under a weight and slowly giving you more and more of the load until
you have control of the weight. Immediately, the weight will drive you into the
negative phase. Fight the weight on the way down, and be careful to not descend
too quickly because that may predispose injury.
Communication with your
partner here is critical. You should be prepared mentally and physically for
what will be a very high workload; it is quite taxing to drive with all your
might against a load that’s moving in another direction. Be sure to maintain
good mechanical position throughout.
Bob LeFavi is a professor
of sports medicine at Armstrong State University in Georgia and co-owner of
CrossFit GroundSpeed. He also competed in the 2013 Reebok CrossFit Games,
Masters division.
Front Squat
This is a great exercise
to work eccentrically because it translates strength gained to so many other
CrossFit movements — cleans, thrusters, wall balls and box jumps, just to name
a few. While partner-assisted and accentuated-eccentric training work well with
front squats, we suggest adding eccentric-only work to your front-squat
regimen.
After warming up, increase
to a load that is at least 115 percent of your front-squat maximum. Most
experienced lifters who focus on eccentric training would not hesitate to go to
140 percent of maximum, but do not start there.
Position yourself under
the bar situated in a rack. Grasp the bar in a front-rack position. The step
back is critical because for very brief periods during the walk, you’re on one
leg. In fact, the walk away from the rack may be the most difficult part of the
movement for some. Try to keep the walk to one step with each leg.
Descend slowly and under
control, inhaling on the way down. Focus on your quadriceps taking the load,
always ensuring that your heels are flat and torso upright. When you get to
your bottom position, dump the bar quickly in front of you.
Bench Press
Many athletes were first
introduced to “negatives” with standard bench presses. Sure, CrossFit HQ has
been programming bench presses more and more, but while the exercise per se
will likely never be a CrossFit standard, the movement translates to push-ups,
burpees, planks, handstand push-ups and any overhead exercise.
Negatives on bench presses
are best performed partner-assisted. Be very careful with these, particularly
when using a barbell. The bar forces your shoulder joint into a specific
position, and suddenly loading that joint can be dangerous; the shoulder joint
was simply not designed to endure high impact in the bench-press position. Your
partner should allow you to engage the weight gradually. In addition, your
partner should be positioned at your head and have a reverse grip on the bar in
barbell bench presses. With dumbbell presses, your partner should lift the
weight at your wrists, not your elbows. Two to three sets of four to six reps
is more than adequate for this high-intensity movement.
Pull-Up/Ring Dip
Using the eccentric-only
and accentuated-eccentric methods can perform eccentric training for pull-ups
and ring dips. Both can be accomplished through weighted descents. There are
two general ways to perform weighted descents in these exercises.
For an athlete who does
not have the strength to perform a pull-up (strict, kipping or butterfly) or
ring dip without assistance, simply using bodyweight in a jumping pull-up or
ring dip is a very good method to bring in eccentric muscle work. To perform a
jumping eccentric pull-up or ring dip, jump high enough so (a) in a pull-up,
your chin clears the top of the bar, or (b) in a ring dip, you achieve the top
lockout position. At that point, your task is to lower yourself as slowly as
possible.
For an athlete who can
perform pull-ups or ring dips, using weights from the top/lockout position is
the best way to add eccentric training to these movements. We do not recommend
jumping with weights. The additional weight can come by way of a loaded flak
jacket, a weighted hip harness (which loads weight from a chain that dangles
between the legs) or a dumbbell pinched between bent knees. The key is to start
the movement from the top position and lower yourself as slowly as possible.
With each set, try to slow the descent down to a maximum of four seconds. Be
careful to not drop too quickly into a descent.
Shoulder Press
Eccentric training for
overhead deltoid work can be accomplished with all three methods. To perform
eccentric-only and/or accentuated-eccentric shoulder presses, use a rack with a
loaded bar set 2 inches lower than your standing lockout position. Keeping a
tight torso and elbows locked, step under the bar and carefully stand with it
in an overhead position. Lower the bar, fighting it on the way down. You can
use lower pins to rack the bar or dump it. In the next rep, descend even more
slowly, again working to a four-second descent.
To do partner-assisted
negatives, use the same racking technique, but following a slow descent, your
partner helps you raise the bar back up by providing force to the bar. Having
your partner assist by pressing on your elbows is a commonly used technique,
but that position is less safe. It’s also important that your partner be
positioned directly behind you and that he or she is strong enough to maintain
force on the bar to the top of the movement. If that’s not the case, perform
presses from a seated position in the rack. Be careful to gauge the load so
that it’s possible for your partner to provide enough assistance to safely
raise the weight.
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