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Although not as heralded as its anterior counterpart
the pectoralis major or chest, the latissimus dorsi is synonymous
with that elusive, highly sought after V-taper. Unfortunately, due
to the inability to see the back while training combined with the
extreme volume of work performed for the pectoralis major, many
trainees neglect proper balance in their upper body training opting
to prioritize chest development. We will continue our series on
utilizing proper biomechanics as a means to optimizing your own
developmental potential. This month we will focus on the latissimus
dorsi muscle.
Kinesiology
The latissimus dorsi has two main actions on the arm. It functions
in adduction (pulling the arms to the sides of the body from an
out-to-the-side position) and extension (pulling the arms down from
a horizontal position straight out in front of the body. As we will
see, knowing these two primary actions will be a great tool for
understanding the proper biomechanics for latissimus dorsi exercises.
As noted above, the lattisimus dorsi muscle has a strong action
in adduction of the humerus. Whenever we have our hands above our
head, as with seated pulldowns or while doing pull-ups, due to the
upward rotation of the scapula that accompanies glenohumeral abduction,
the latissimus dorsi effectively downwardly rotates the scapula
by pulling the entire shoulder girdle downward in active glenohumeral
adduction. Since it is one of the most important extensor muscles
of the humerus, it contracts powerfully in chinning and supinated
pull-downs. Therefore, any exercise in which the arms are pulled
down bring the latissimus dorsi into a full contraction. Basic rowing
and pullover exercises with dumbbells or barbells are also good
for latissimus dorsi development.
Any discussion of the latissimus dorsi must include a mention of
the teres major muscle. The teres major is commonly referred to
as the "lats' little helper" because the two have the
exact same action on the arm. It is impossible to train one without
the other. The origin of the teres major is on the lower edge of
the scapulae (shoulder blades) above the latissimus dorsi. The insertion
is on the head of the humerus, in virtually the same spot as the
insertion of the latissimus dorsi.
| Muscle |
Origin |
Insertion |
Action |
Innervation |
| Latissimus dorsi |
Posterior crest of illium,
back of sacrum and spinious process of lumbar and lower
T6-T12; slips from lower 3 ribs |
Medial side of intertubercular
groove of humerus |
Addition, extension and internal
rotation of glenohumeral joint also horizontal abduction
of glenohumeral joint |
Thoracodorsal nerve (C6-8) |
| Teres major |
Posteriorly on inferior 3rd
of lateral border of scapula and slightly superior to
inferior angle |
Medial lip of intertubercular
groove of the humerus |
Extension, internal rotation
and adduction of glenohumeral joint |
Lower subscapular nerve (C5,
C6 |
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Recommended Exercises
Overhead Pulldown
Proper Position:
- Grasp the bar using a pronated grip approximately 6 inches
wider than shoulder width.
- Grasp the bar with the arms slightly bent with the elbows pointed
away from the body.
- Make sure that the knees are placed firmly under the support
pads and that your feet are planted firmly on the ground.
- Lean back slightly (approximately 15 degrees) to allow the
bar to travel in a correct downward path.
- Maintain a natural arch in the lower back. This is the starting
position.
Proper Form:
- From the starting position, pull the shoulder blades down and
together and begin to contract the latissimus dorsi muscle by
initiating contraction by bending the elbows.
- Pull the arms down and out until the bar touches your clavicle.
- Keep the scapulae retracted and depressed.
- Contract the latissimus dorsi while relaxing the hands and
arms.
- In a controlled manner, return the bar back to its starting
position and repeat.
Essential Tips:
- Concentrate on keeping the hands and arms relaxed while contracting
the latissimus dorsi.
- Maintain a natural arch in the spine at all times.
- Keep the head and neck in a neutral position throughout the
exercise.
Seated Cable Row
Proper Position:
- Plant your feet firmly against the foot platform.
- Grasp the pulley handles, and with your legs push yourself
while simultaneously pulling with your back until you are in an
upright seated position.
- Sit up in a ready position with your hips and knees slightly
bent and a natural arch in your lower back.
- Keep the elbows slightly bent pointed down. This is the starting
position.
Proper Form:
- From the starting position, retract the scapula by pulling
the shoulder blades down and squeezing together.
- Contract the latissimus dorsi by pulling the arms back until
the elbows are about straight down from the shoulders.
- Continue to contract the latissimus dorsi as well as the rhomboids
and middle trapezius.
- In a controlled fashion, return to the starting position.
Essential Tips:
- Avoid rotating the shoulders during execution.
- Keep the elbows pointed down throughout the exercise.
- Maintain a natural arch in the lower back.
- Keep the head and neck in a neutral position.
Bent-Over Row
Proper Positioning:
- Plant your feet firmly on the ground in a stance slightly wider
than shoulder width apart with the knees slightly bent.
- Bend your upper body forward slightly above parallel to the
floor.
- Grasp the bar with a pronated grip slightly wider than shoulder
width.
- Allow the bar to hang with the elbows fully extended. This
is the starting position.
Proper Form:
- From the starting position, retract the scapula by pulling
the bar up toward your lower chest.
- Continue to contract the latissimus dorsi until the elbows
are pointed directly up.
- Continue to contract the latissimus dorsi as well as the middle
trapezius and rhomboids, while trying to relax the hands and arms
as much as possible.
- In a controlled fashion, return to the starting position.
Essential Tips:
- Avoid jerking the torso for assistance.
- Maintain a rigid upper body, with the back flat.
- Keep the head and the neck in a neutral position (focus the
eyes a short distance ahead of the feet).
- Keep the torso and knees in the same position throughout the
exercise.
In addition to proper biomechanics, it is essential to incorporate
proper stretching techniques in your client training. The latissimus
dorsi is stretched with the teres major when the shoulder is externally
rotated while in a 90 degree abducted position. This can be accentuated
by abducting the shoulder fully while maintaining external rotation
and then laterally flexing and rotating the trunk to the opposite
direction.
By having a stronger comprehension of the proper biomechanics of
the latissimus dorsi muscle, as well as correct methods in which
to stretch this muscle, you can successfully design a program in
which you can optimize your latissimus dorsi muscle potential as
well as all of your future clients. Preparation, persistence and
hard work will help you reach your potential. Until next month,
train hard and continue to live the fitness lifestyle.
Please direct all questions or comments to patrick@issaonline.com.
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