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1. Your body is a unit, and the muscles that make up your
body is a team. One of my favorite logical examples to
explain to people the importance and valid placement of
compound and isolation movements is the snow dog logic.
One snow dog may be able to pull 50lbs uphill for 100
yards, but if you put nine snow dogs together they will pull
nine times the weight and for longer distances. Once one
of your snow dogs become weaker and can't keep up with
the pack, you isolate that snow dog and give it direct focus
and bring up its lagging parts; that way, when the snow
dogs are reunited, they are stronger as a unit.

2. The prime mover in your muscles is something called an
agonist. The agonist muscle in a particular exercise is
found in accordance to the direct function of that
particular muscle; what joint that muscle controls. The
elbow is controlled by two potential muscles: the biceps
and the triceps. The biceps is the agonist muscle in curl
and pulling focused movements, because during these
movements, the elbows are flexing against gravity. The
triceps are responsible for extension and pushing forced
movements, because during these movements, the
elbows are extending against gravity. In a tricep extension,
the triceps are the agonist. In the biceps curl, the biceps
are the agonist.

3. In a single joint focused exercise, there is one particularly
focused muscle: the agonist. These exercises are called
isolation exercises are intended to bring up a lagging part.
For example, if your biceps are causing you to fail during
your bent over rows, then adding bicep curls to further
strengthen the bicep muscles, as well as increase the
amount of motor units activated in your biceps is the
logical explanation for continuous progression of your
bent over rows.

4. What happens when you are working more than one point
at a time? These movements are called compound
movements, and they are the bread and butter of any
successful routine with functional strength as an
important card on the table. When you perform a
compound exercise, multiple joints are activated and this
means that different muscles will play different roles.

5. During a compound movement, you will have a group of
prime movers, with one of those prime movers, being the
agonist (primary mover). The other prime movers are
simply secondary role players that assist with the larger
muscle. As I mentioned earlier, your body is a team, and
these muscles must learn how to work together in order
to accomplish particular actions.

6. During the bench press, the chest is the agonist, prime
mover. Why? Because pushing in-front is a major function
of the chest; there are other muscle groups major function
activated during the bench press. The triceps are activated
during the elbow extension phase of a bench press, and
the deltoids; particularly the anterior deltoids, are
activated as the scapula flexes.

7. These other muscles involved in the concentric loading of
a bench press are called synergist muscles. A synergist will
assist in concentric contraction to another muscle in
accomplishing a multiple joint focused completion of
movement. For example, without the triceps the chest
cannot push in front, and without the scapula the chest
cannot push in front, so these muscles must coordinate
with the chest in order to complete an infront push: bench
press.

8. The triceps, deltoids, and chest are not the only muscles
involved with a bench press. While the chest is the agonist
(prime mover), and the triceps and anterior deltoids are
synergists to the movement, there are also isometric
contractions occurring during this range of motion. These
muscles contract isometrically in order to stabilize a
particular joint and as a result, they are called stabilizer
muscles.

9. The role of a stabilizer is significantly different from the
role of an agonist or synergist. A stabilizer does not usually
have a concentric function, which means it does not
shorten or move during the exercise, but it stabilizes a
specific joint, so the other joints can perform their desired
range of motion. In this example, the forearms have to
stabilize the wrist during the bench press to keep a right
angle between the humerus and ulna/radius. If the wrist
would extend, then you would potentially break your
wrist and have the weight fall on you and hurt you. The
biceps must isometrically contract to keep the bar in
neutral positioning during this lift.

10. There is another muscular role in compound movements
that has not been specified yet, and that role is called an
antagonist. Since an agonist muscle is a prime mover, then
an antagonist is the complete opposite of this. Antagonists
oppose the action of the agonist. For example, since the
triceps extends the elbow and the biceps flexes the elbow,
the biceps is the antagonist in extension exercises and the
biceps are the antagonist in flexion exercises. During a
bench press, the upper back muscles and retractors of the
scapula, as well as the muscles that externally rotate the
humerus would serve as antagonists. In order for proper
balance at the joint, these muscles will need to be worked
equally.

11. The team of muscles that work together during a
compound movement are the agonist (prime
mover), synergist (assistant mover), and the stabilizers
(muscles that stabilize a particular joint, so the prime
movers and assistant prime movers can perform their
desired function). These muscles teach better
intramuscular coordination and therefore teaches your
muscles how to properly work together for real world
tasks like pushing a car off the road or pushing an fallen
object off your body. If you do not train your muscles how
to work together properly, then they will be non-
coordinated and will not learn how to perform specific
tasks in which they are required to work as a unit.

12. For example, if you isolated your quads, posterior chain
muscles (glutes, hamstrings) with exercises like hamstring
curls and leg extensions, your body will still get stronger.
However, your muscles would lack coordination and they
would pick up an inability to work together during tasks.
For example, when you see an athlete preparing for a
massive vertical leap, they are usually performing power
cleans, deadlifts, and squats. These movements are
compound movements and recruit all the muscles
required for a vertical leap and teaches this proper
coordination of muscles. This type of strength is called
functional strength, which means that it has potential
carryover into the real world.

13. Another benefit to compound movements over isolation
movements is the ability to make continuous linear
progression. Each workout, the muscle has to be placed
with more stress than it was the previous in order for
optimal growth to occur. If you workout with the same
weight each week, you're not giving your body a new
stimulus to grow from but rather adapt to the stimulus it
has already been given and only to perform this desired
weight more efficiently.

14. A person can gain 100lbs on their bench press very quickly
and easily, but how many people have ever in a lifetime
added 100lbs to their flies? Your flies may "feel better" on
your pecs, but that is only because your pecs are the only
muscle involved in the loading and the progress will be
minimal. Your might find you will gain 20lbs on the lift, but
then will find it unable to make further progression. Not
to mention, your functional carryover into other lifts will
be minimal.

15. When a person bench presses, their
chest, triceps, deltoids, back, trapeziums, and forearms all
get a workout. This causes an increased tension to the
body as a whole and the result is the body forcing the
endocrine system to release "medics". These "medics" I
am referring to is an anabolic steroid hormone produced
in the testicles called "testosterone". Testosterone is made
from cholesterol, and aids in the enhancement and
increments of contractile proteins like myosin and actin.

16. The anabolic hormone "testosterone" that is released, is a
result of increased muscular strength, endurance, and
hypertrophy. Isolation movements recruit very little if any
at all testosterone release. Big compound
movements, particularly squats and deadlifts, recruit the
most anabolic hormones like testosterone.

17. Continual linear progression, increased functional
strength, more anabolic hormones, and more carryover
into other exercises are all reasons so far that compound
movements are superior to isolation movements. If your
triceps begin to fail on a bench press, then you can begin
to add other movements to focus specifically on triceps
development, but this will usually take a while. The bigger
chances are if your bench press is stalling you are either
not eating enough or you have jumped the gun and
started too heavy.

18. First of all, you have to find out if it really is the triceps
that is failing. How would you know? Simple. You find out
what particular phase of the bench press the triceps have
the most involvement in and you would see if that is the
phase you are failing. The triceps is responsible for
"extension" of the elbow and extension of the elbow
occurs at the lockout phase of a bench press. If you can get
the bar off your chest, but cannot get it to lockout, then
most likely it is your triceps failing you.

19. The biggest compound exercises are:
squats, deadlifts, overhead presses, bench presses, bent
over rows, pullups. Those movements all should be staples
with any successful compound movement focused routine.
Accessory compounds that are alright to have involved are
weighted dips, close grip bench presses, power cleans, and
front squats.

20. The moral of the article has hopefully provided you with
the knowledge and understanding of compound
movements and their importance, as well as an analogy of
when isolation movements are necessary.

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