What are the key muscles of the deadlift? Part 3: The Trapezius 

Welcome to the "Deadlift: Muscles Worked" series! Maybe you've just started lifting weights. Maybe you're a trainer who wants to learn the nitty gritty about this exercise. Whatever the case, welcome!

In this article, we're going to focus on the "trapezius". 

The entire trapezius muscle (comprised of the lower traps, mid traps, and upper traps) is a key muscle in the deadlift. In this article, we're going to explain:

1. How each part of the trapezius muscle works in the deadlift
2. How you might get injured if your trapezius muscle doesn’t work in the deadlift
3. How to cue your trapezius muscle to work in the deadlift

How does each part of the trapezius muscle work in the deadlift?

Let’s begin by establishing what’s going on at your shoulder complex in a deadlift.

In a deadlift, as you’re picking the bar off the floor… gravity (via the weight of the bar) is attempting to rip your arms off your body.

Your arms attach to your shoulder blades.

So:

As you’re picking the bar off the floor… gravity is attempting to rip your shoulder blades off your body too.

How?

One way is by pulling the BOTTOMS of your shoulder blades AWAY from your rib cage.

Imagine gravity pulling the shoulder socket down… as the bottom of the shoulder blade follows.

This is called scapular anterior tilt.

This is where your lower traps come in to save the day.

Your lower traps pull the BOTTOMS of your shoulder blades TOWARDS your rib cage… as gravity tries to pull the BOTTOMS of your shoulder blades AWAY from your rib cage.

How do your lower traps do this?

Your lower traps attach on the top halves of your shoulder blades… and run DOWNWARD towards your spine.

So:

With your spine held in place by other muscles… squeezing your lower traps will compress the BOTTOMS of your shoulder blades… TOWARDS your rib cage.

So:

Your lower traps work in the deadlift to stabilize your shoulder blades.

Now what about your mid traps? How do they work in the deadlift?

To answer this:

Let’s examine another direction in which gravity is trying to rip your shoulder blades off your body.

As your torso is leaned over… gravity is trying to pull the INNER EDGES of your shoulder blades AWAY from your rib cage.

Imagine gravity pulling those arms down… as the inner edges of the shoulder blades follow.

This is called scapular internal rotation.

(Extreme) scapular internal rotation

This is where your mid traps come in to save the day.

Your mid traps pull the INNER EDGES of your shoulder blades TOWARDS your rib cage… as gravity tries to pull the INNER EDGES of your shoulder blades AWAY from your rib cage.

Rotation of the right scapula... as seen from above the torso

Scapular Internal Rotation vs. External Rotation

How do your mid traps do this?

Your mid traps attach on the top halves of your shoulder blades… and run SIDEWAYS towards your spine.

Your mid traps are in red. 

So:

With your spine held in place by other muscles… squeezing your mid traps will compress the INNER EDGES of your shoulder blades… TOWARDS your rib cage.

So:

Your mid traps work in the deadlift to stabilize your shoulder blades.

Finally, what about your upper traps? How do they work in the deadlift?

To answer this:

Let’s examine another direction in which gravity is trying to rip your shoulder blades off your body… specifically as your torso approaches a fully upright position.

As your torso approaches a fully upright position… gravity is trying to pull the outer corners of your shoulder blades DOWNWARDS (relative to the other corners).

Imagine gravity pulling the arms down… as the outer corners of the shoulder blades follow.

This is called scapular downward rotation.

This is where your upper traps come in to save the day.

Your upper traps pull the OUTER CORNERS of your shoulder blades UPWARDS… as gravity tries to pull the OUTER CORNERS of your shoulder blades DOWNWARDS.

Scapular Downward Rotation vs Upward Rotation

How do your upper traps do this?

Your upper traps attach on the OUTER CORNERS of your shoulder blades (via your collarbones)… and run UPWARDS towards your neck.

Upper traps in orange

So:

With your neck held in place by other muscles… squeezing your upper traps will compress the OUTER CORNERS of your shoulder blades TOWARDS your neck.

So:

Your upper traps work in the deadlift to stabilize your shoulder blades.

How might you get injured if your trapezius muscles don’t work in your deadlift?

To answer this question…

Let’s review how each part of your trapezius muscle works in the deadlift.

Your lower traps produce scapular posterior tilt… to neutralize gravity’s scapular anterior tilt.

Your mid traps produce scapular external rotation… to neutralize gravity’s scapular internal rotation.

What happens when scapular anterior tilt, internal rotation, and downward rotation are not controlled for during deadlifting?

Your shoulder blades destabilize from the rest of your body, in one way or another.

Your shoulder blades destabilize from the rest of your body, whether to an extreme amount… or to an imperceivable amount.

This is called “winged scapula”. And what are the consequences of lifting with winged scapulae?

One… you won’t be able to lift as much weight because now your arms are destabilized from the rest of your body.

Two… things around your shoulders may jam into each other… and this has consequences.

What are the consequences if the traps aren't working in the deadlift? 

In other words... what things may jam into each other? And what are these consequences?

There are a couple major issues that can occur.

First, there's loss of blood flow to your hands...

Let’s recall that your shoulder blades (scapulae) are attached to your collarbones (clavicles).

If the outer corners of your shoulder blades are stuck tipped forward (anteriorly tilted) and/or pointed down (downwardly rotated)... where do you think your collarbones will go?

Your collarbones will be stuck rolled forward and down too.

What then?

Your collarbones may chronically compress whatever it lies between them... and your first ribs.

What lies between your collarbones and your first ribs?

Nerves and blood vessels that run down to your hands.

Nerves and blood vessels that, if you chronically compress… you may induce pain, tingling, and/or weakness in your arms and hands.

This phenomenon is common enough to have been given a name -- Thoracic Outlet Syndrome. This will definitely interfere with your ability to deadlift injury-free.

But don’t get stuck on the medical diagnosis.

Know that to deadlift injury-free:

You need to be able to position your shoulder blades where ever they need to be to allow your arms to move… WITHOUT your collarbones compressing the nerves and blood vessels that run to your hands.

So what’s another way you may get injured if your trapezius doesn’t work in your deadlift?

To answer this question…

Let’s recall that your arms are attached to your shoulder blades.

This means:

If the outer corners of your shoulder blades are stuck excessively pointed down...

And you try to lift your arms in front of you or away from your sides (as you might during your deadlift setup)…

Your arms may jam into the outer corners of your shoulder blades.

What happens when you continually try to jam two bones through each other? Something will hurt.

This phenomenon is common enough to have been given a name -- shoulder impingement. This will definitely interfere with your ability to deadlift injury-free.

But don’t get stuck on the medical diagnosis.

Know that to deadlift injury-free:

You need to be able to position your shoulder blades where ever they need to be to allow your arms to move… WITHOUT your arms jamming into your shoulder blades.

Finally…

Why are the lower traps, mid traps, and upper traps so crucial for shoulder blade stability in the deadlift?

In other words, why can’t the traps go on vacation and let other muscles take over for them?

Here’s why:

You have other back muscles that can and do assist in said functions of the trapezius. But none of them are as large, as powerful, or as well positioned on your body as the trapezius is… to do what the trapezius does.

So you’d not only be limiting how much you can lift. You’d also incur a muscle injury much sooner by relying on a less effective muscle to take over any of the trapezius’s functions.

The bottom line?

Ensuring your trapezius (all its parts) are working properly is essential for effective, injury-free deadlifting.

How do you cue your trapezius muscle to work in the deadlift?

There are three major steps. 

1. Step 1: Learn to feel your lower traps working in isolation.
2. Step 2: Learn to feel your mid traps working in isolation.
3. Step 3: Learn to feel your lower and mid traps working in the deadlift.

Step 1:

Practice the “Trap-3 Raise” to isolate your lower trap. Follow the instructions in the video. As well as the ones below.

As you lift your arm, create the intention of rotating your inner elbow (the “funny bone”) UPWARDS to the sky.

This is because as you lift your arm in this exercise, the temptation will be to rotate your inner elbow DOWNWARDS to get your arm higher. If you allow this to happen, then it takes work away from the lower trap. And this defeats the purpose of the exercise.

So once you sense the temptation to rotate your inner elbow DOWNWARDS... create the intention of rotating your inner elbow UPWARDS.

If you perform this exercise correctly, you will feel your mid back region squeezing. That’s your lower trap working.

At first, this area may be difficult to feel. Have patience.

Once you’re able to feel your lower trap working, practice engaging it until it becomes second nature.

Step 2:

Practice the “Pull-Apart” to isolate your mid trap. Follow the instructions in the video. As well as the ones below.

As you pull your arms apart, create the intention of rotating your inner elbow (the “funny bone”) DOWNWARDS to the floor.

This is because during this exercise, the temptation will be to rotate your inner elbow UPWARDS to get your arms further behind your body. If you allow this to happen, then you’re taking work away from your mid trap. And this defeats the purpose of the exercise.

So once you sense the temptation to rotate your inner elbow UPWARDS... create the intention of rotating your inner elbow DOWNWARDS.

At first, this area may be difficult to feel. Have patience.

Once you’re able to feel your mid trap working, practice engaging it until it becomes second nature.

Step 3:

Cue your lower and mid traps to work in the deadlift.

Perform your usual deadlift setup. And pay extra attention to your lower and mid traps’ attachments on your shoulder blades.

Gently squeeze your lower and mid traps to stabilize your shoulder blades. Then maintain this squeeze through the rest of your deadlift.

Feel how engaging your lower and mid traps pulls your shoulder blades snug to your rib cage… and how this then helps you more stably hang heavy things (e.g. a barbell) from your arms.

Practice sensing your traps’ influence on your upper body stability during your warm-up sets.

Practice sensing your traps’ influence on your upper body stability during your work sets.

Practice sensing your traps’ influence on your upper body stability whenever you'd like, until doing so becomes second nature to you.

At that point, you can rest assured that you have mastered this essential component of injury-free deadlifting.

Sources

THE ROLE OF THE SCAPULA (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3811730/)

• “most of the abnormal biomechanics and overuse injuries that occur about the shoulder girdle can be traced to alterations in the function of the scapular stabilizing muscles”

Scapular muscle recruitment patterns: trapezius muscle latency with and without impingement symptoms. (https://www.ncbi.nlm.nih.gov/pubmed/12860542/)

• “The findings support the theory that impingement of the shoulder may be related to delayed onset of contraction in the middle and lower parts of the trapezius muscle.”

Effect of trapezius muscle strength on three-dimensional scapular kinematics (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4932076/)

• “Shoulders with stronger upper trapezius muscles showed greater upward scapular rotation at 30°, 60°, 90°, and 120° of elevation in the frontal plane.”

Scapular and rotator cuff muscle activity during arm elevation: A review of normal function and alterations with shoulder impingement (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2857390/)

• “The middle trapezius plays primarily a stabilizing role in controlling scapular position. Delayed activation of this muscle in response to a perturbation of dropping the arm has been identified in impingement patients. Thus use of exercises for this muscle in rehabilitation programs may be most appropriate for patients with excess scapular internal rotation presenting as prominence of the medial or vertebral scapular border.”

Current Concepts in the Scientific and Clinical Rationale Behind Exercises for Glenohumeral and Scapulothoracic Musculature (https://www.jospt.org/doi/10.2519/jospt.2009.2835)

• “As previously mentioned, the lower trapezius is an extremely important muscle in shoulder function due to its role in scapular upward rotation, external rotation, and posterior tilt.”

Thoracic outlet syndrome part 2: conservative management of thoracic outlet. (https://www.ncbi.nlm.nih.gov/pubmed/20382063)

• “Thoracic outlet syndrome (TOS) is a symptom complex attributed to compression of the nerves and vessels as they exit the thoracic outlet. Classified into several sub-types, conservative management is generally recommended as the first stage treatment in favor of surgical intervention.”

A comparison of trapezius muscle activities of different shoulder abduction angles and rotation conditions during prone horizontal abduction (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4305608/)

• “PHA (prone horizontal abduction) accompanied by ER with shoulder abduction at 120° should be effective at inducing high activity in the LT when PHA is performed by patients with scapular dyskinesis.”

Movements of the Scapula - YouTube (https://www.youtube.com/watch?v=LF7oST34r4s)

Romanian Deadlift - YouTube (https://www.youtube.com/watch?v=8tTKm-3wX5s)

How to Avoid Injuries While Lifting: Watch the muscles in 3D - YouTube (https://www.youtube.com/watch?v=lVxnRAiuGas&)

Asymptomatic Scapular Winging - YouTube (https://www.youtube.com/watch?v=iVP6o-cyzM8&)

SCAPULAR DYSKINESIS - YouTube (https://www.youtube.com/watch?v=_YbSANkJ9ow&)