Defining the "back"
The Upper Back Musculature
Firstly let's talk about the upper back. In the upper back we have a variety of muscles but for the purposes of this blog I will address the major ones which are the latissimus dorsi, teres major, rhomboid major/minor and trapezius. I'm about to get a little anatomy heavy so brace yourselves.
Latissimus Dorsi
Attachments: iliac crest of pelvis, thoracolumbar fascia, lower three to four ribs, inferior angle of the scapula, humerus. What this means is it attaches to the pelvis, a bunch of stuff in the middle including the spine (indirectly), ribs, shoulder blade and finally attaches to the upper arm bone.
Actions: shoulder joint extension, shoulder joint adduction, shoulder joint internal rotation. In other words it brings the arm back to the side from the front and the side and it rotates the arm inwards.
Teres Major
Attachments: posterior surface of scapula near the inferior angle, humerus (bottom of back of shoulder blade to the upper arm bone)
Actions: shoulder joint extension, shoulder joint adduction, shoulder joint internal rotation. These are similar actions to the latissimus dorsi.
Rhomboid Major/Minor
Rhomboid Major Attachments: spinous processes of T2 - T5, medial border of scapula
Rhomboid Minor Attachments: spinous processes of C7 and T1, medial border of scapula
(this means it attaches to the thoracic spine and the shoulder blade on the same side)
Actions: scapula retraction (it pulls the shoulder blades backwards).
Trapezius
Attachments: occipital bone, ligamentum nuchae, spinous processes of C7 - T12, lateral third of clavicle, acromion process and spine of scapula. In other words the trapezius muscle attaches to the skull, a ligament that runs down the back of the neck, the full length of the thoracic spine and attaches onto the collar bone and shoulder blade on each side of the body.
Actions: scapula retraction, scapula depression, shoulder girdle elevation, cervical extension, cervical lateral flexion. Translation - it does a few things because it has different sections. It pulls the shoulder blades backwards, downwards, lifts the shoulder blades and attached structures up and bends the neck backwards and to the side.
The Lower Back Musculature
When discussing the lower back muscles I firstly want to note that there are a whole bunch of muscles which have functions in this area. There are muscles that extend the trunk, that laterally flex the trunk, that rotate the trunk and that flex the trunk. There are also muscles that can increase intra-abdominal pressure and others that produce inspiration and expiration (breathing). For the purpose of this discussion I'm going to cover only the muscles which produce extension of the lower back. These muscles are quadratus lumborum, multifidus, erector spinae and interspinales.
Quadratus Lumborum
Attachments: iliac crest, iliolumbar ligament, lumbar transverse processes, twelfth rib. More or less it attaches to the pelvis and up top to the twelth rib with some attachments in between to the lumbar spine.
Actions: lumbar spine lateral flexion, lumbar spine extension. This means it bends the trunk to the side and, when both sides contract, to the rear.
Multifidus
Attachments: sacrum, lumbar vertebrae mamillary processes, thoracic vertebrae transverse processes, lower cervical vertebrae articular processes, spines of all vertebrae from L5 to the axis in the cervical spine. This is a deep muscle clearly with extensive attachments from the sacrum at the base of the spine all the way up the spine to the top of the neck. It has several layers which span between one and three levels of vertebrae at a time.
Actions: rotation, lateral flexion and extension of the spine. Basically this muscle rotates, bends to the side and bends the spine to the rear.
Erector Spinae (iliocostalis, longissimus, spinalis ie there are three sections of erector spinae)
Base Attachments: T11 - L5 spinous processes, median sacral crest, iliac crest. For the non anatomically inclined this means the muscle group attaches at the bottom to the lumbar spine, sacrum and pelvis. The erector spinae then splits into three columns as described below.
Iliocostalis Attachments: ribs 1 - 12, C4 - C7 transverse processes (the attachments of this section of erector spinae span from the base attachments to the ribs to the middle of the neck).
Longissimus Attachments: lumbar transverse processes to T1 - T12 transverse processes and lower 10 ribs. T1 - T6 transverse processes to C2 - C6 transverse processes. T1 - T5 transverse processes and C4 - C7 articular processes to mastoid process. (the attachments of this section are extensive and run from the lumbar spine to the thoracic spine and ribs and into the neck).
Spinalis Attachments: T1 - T6 spinous processes (the attachments of this erector spinae section are from the lumbar spine to the thoracic spine).
Actions: lumbar, thoracic and cervical extension, trunk lateral flexion, trunk lateral rotation. That is, this muscle group bends the spine to the rear, to the side and rotates it to the same side.
Interspinales
Attachments: in between spinous processes mainly in the cervical and lumbar spine ie in between vertebrae in the neck and lower back.
Actions: cervical and lumbar extension. In other words, this muscle helps to bend the neck and the lower back to the rear.
Now that covers the anatomy of the upper and lower back muscles in detail. Apologies if you got lost in the terminology. I did try to include some layman's descriptions for each part to keep everyone on track. For the most part the muscles of the upper back move the shoulder joint and shoulder blades around and the muscles that I described in the lower back and spine move the spine in a few different directions. As well as producing movement, they can also all control or prevent movement in the opposite direction. For example the erector spinae group can control or prevent lumbar flexion (bending forward of the trunk). All this is important for what we are going to discuss regarding deadlifts.
The Deadlift - a basic description
The deadlift is a hip dominant movement. Whether you are pulling conventional or sumo stance you're always going to start in knee flexion, hip flexion (hips and knees bent), with an ideally neutral lumbar spine. During the concentric phase of the movement the hips and knees will extend (straighten) simultaneously until both full knee and hip extension are reached. The motion is reversed for the eccentric phase. Throughout the motion the lumbar spine should remain in neutral. If the lifter cannot get into a neutral spine position to begin with that is ok but the lumbar spine should remain in that position throughout the lift. It should not move further into flexion or further into extension (bend further forwards or backwards) for injury prevention reasons.
What are the major movers in a deadlift?
The two major movements that occur in a deadlift are hip extension and knee extension. The muscles which extend the hip are gluteus maximus and the hamstrings (semitendinosus, semimembranosus and biceps femoris). The muscle which extends the knee joint is quadriceps femoris. I don't think it's necessary to go over their anatomy for the purposes of this discussion, so long as we understand what muscles they are and what they do.
As an added note - as you can see from the previous discussion of the upper and lower back anatomy, the lumbar extensors and the upper back muscles I have mentioned do not cross the hip joint. As such they aren't involved in extending the hips (the primary motion of the deadlift).
The role of the upper and lower back musculature in a deadlift
So if the muscles that are doing the actual moving in a deadlift are the hip and knee extensors as described above then what are the muscles in the upper and lower back doing? The simple answer is they are contracting isometrically to prevent movement and stabilise joints in certain areas.
When we are setting up a deadlift one of the things we do is pack our lats and retract our shoulder blades. The muscles that are achieving this are the latissimus dorsi/teres major (shoulder extension) and the rhomboids/trapezius (scapula retraction). These muscles then help to hold this position by way of isometric contraction throughout the lift.The rhomboids and trapezius are of course holding the shoulder blades in place and the latissmus dorsi because of it's multiple attachments (shoulder, scapula, ribs, spine, pelvis) serves as a stabiliser of the trunk locking it's position down.
The lower back muscles I described earlier (quadratus lumborum, multifidus, erector spinae, interspinales) are also contracting isometrically. However the movement they are primarily resisting is trunk flexion. That is, they are stopping the bar from pulling our back into a bent position whilst our hip and knee extensors do the moving part.
So the upper and lower back muscles are actually playing a very important role here. They are resisting unwanted motion in the trunk and stabilising joints for optimal position. These muscles are all working hard when we deadlift but they are secondary to the lift in that they are stabilisers working isometrically. They don't (or shouldn't) produce any significant movement during the lift.
Alberto Nunez sumo deadlifting. As you can see his back is doing a lot of work (video included below)
So do deadlifts develop your back?
Yes deadlifts will develop the muscles of both your upper and lower back. But you need to keep in mind that their role in the lift is secondary. Their contraction is isometric and they aren't moving any joints through a range of motion. So whilst they do contract and they will hypertrophy, doing a deadlift is not the most efficient means of developing these muscles. The most efficient way to develop these muscles is to perform exercises which take the involved joints through a full or close to full range of motion (see below):
Latissimus dorsi and Teres major: Pull ups, pull downs, rows, pull overs
Rhomboids and Trapezius: Rows, shrugs
Lumbar Extensors: Back extension variations on the floor or on equipment
These are better options if your goal is specifically hypertrophy of the upper and lower back musculature. Which is of course not to say deadlifts are not valuable, they are still going to be a contributor to hypertrophy of these muscles just not in the sense that a prime mover contributes.
Including deadlifts to develop the hip and knee extensors as well as some added hypertrophy benefits for the upper and lower back muscles is a good idea. Attempting to use deadlifts as the primary means to develop the muscles of your back isn't the best idea. This would be akin to doing squats with the purpose of developing your lumbar extensor muscles (the lumbar extensors play a similar isometric role, preventing lumbar flexion during a squat). And of course the primary reason to squat is to develop the lower limb muscles, not the lower back.
Summary
- the role of the gluteus maximus, hamstrings and quadriceps is to extend the hips and knees, producing movement during the deadlift.
- the role of the upper and lower back muscles described in this article is to isometrically stabilise joints and resist movement of the trunk in undesirable directions during the deadlift.
- deadlifting will produce hypertrophy primarily of the gluteus maximus, hamstrings and quadriceps and secondarily of the latissimus dorsi, teres major, rhomboids, trapezius and lumbar extensor group.
- deadlifting used as the primary means of developing the latissimus dorsi, teres major, rhomboids, trapezius and lumbar extensor group is unwise.
- instead incorporate deadlifts for their hypertrophy benefits but include exercises that target the muscle groups that move joints through their range of motion eg pull downs, rows, back extensions etc.
Thank you for reading, that's all for this week. If you have something to add to the discussion please do so in the comment section or on social media. As always you can contact me via the details provided below if you want to speak to me about my coaching services.
Muscle Academy contact details:
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- Evan
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