important muscles for personal trainers

You Need To Start Training These 3 Muscles Today!

important muscles for personal trainers

The Most Important Muscles For Personal Trainers:

But first, why is knowing the anatomy so important for a trainer?

The human body is an incredible thing. So many distinct parts have to function together in order to move efficiently.

Without knowing what parts should be doing the moving, how can we coach our clients on how to get better?

This is why anatomy knowledge is critical for every personal trainer who wants to be successful.

There are many important muscles for personal trainers to know, but these are 3 that are essential to getting your clients unparalleled results.

Serratus Anterior

The Anatomy:

The serratus anterior runs from the inside, front of the shoulder blade to the first 9 ribs.important muscles for personal trainers

It’s main job is to keep our shoulder blade close to our rib cage while the arm is moving.

In movements like pushups or overhead reaching, you may see your clients’ shoulder blades “pop out” away from their rib cage. This is called scapular winging. The serratus anterior is designed to prevent this.

Why we need to work the Serratus Anterior:

Scapular winging can negatively effect every pushing exercise. When the shoulder blade is moving poorly, the shoulder joint is compromised.

We need to strengthen this muscle not only to protect our clients’ shoulders, but to help them move more weight in an efficient manner.

A properly activated serratus anterior can greatly benefit our clients’ bench press, overhead press, etc…

How to Strengthen:

SB Wall Roll-Ups:

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Scapular Punches: Have your client lie supine on a bench holding two light dumbbells. With arms extended, and at approximately 100 degrees of shoulder flexion, have them press the dumbbells up towards the ceiling. Do not allow the elbows to bend. This should be slow and controlled.


The Anatomy:

The multifidus is a collection of very deep back muscles that run from the base of the skull down to the sacrum. They can extend, flex, and rotate the spine.

Since we have other muscles that also do these motions, our client’s can generally appear to do these actions fine without proper multifidus activation. Still, over time, neglecting the deep core muscles can lead to low back pain and other complications.

The main job of this muscle that we should focus on with our clients is spinal stabilization.important muscles for personal trainers

Why we need to work the Multifidus:

This is for sure one of the most important muscles for personal trainers to know due to its intricate relationship to low back pain.

Multiple clinical studies found that improper activation of the multifidus was highly correlated to non-specific low back pain.

The multifidus is designed to activate and stabilize the spine before the desired movement begins. This provides a stable base for the force to be generated from.

When the spine is stable during dynamic exercises, the risk for injuring the low back decreases significantly.

A strong multifidus leads to better performance and less chance of injury. It’s a win-win!

How to Strengthen:

It is difficult to isolate the multifidus without engaging the transverse abdominus and pelvic floor, but this is not an issue. Our clients will benefit from strengthening of all of these muscles.

Exercises like planks and Pallof Presses are ideal. Just make sure to cue your clients to draw their belly button in, and tilt their pelvis back.

Lower Trapezius

The Anatomy:

The trapezius is broken into 3 different muscles, the upper, middle, and lower trapezius. They all connect the spine to the scapula, and move the shoulder blade in different directions.

The upper trapezius is the most well know, but can also be the most problematic.

Due to things like poor sitting posture, and copious amounts of barbell shrugs, the upper traps typically become overactive and tight.

This in turn inhibits and relatively weakens the lower traps.important muscles for personal trainers

Why we need to work the Lower Traps:

When we do any overhead movements, our scapula has to upwardly rotate so that the humerus has room to move. When the shoulder blade is not moving properly, shoulder impingement risk goes way up.

Strengthening the lower trapezius will facilitate improved scapular mechanics via improved upward rotation.

This will help our clients have healthy shoulders and perform better in all overhead exercises.

How to strengthen:

I,Y,T exercise on a stability ball:

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Scapular depressions: This one can be done with bands or cables. Have the band/cable secured up high and client holding the handle directly at side. With arm extended, have them press the handle down by depressing the shoulder only. This reinforces a motion that is typically difficult for people during lots of other exercises. 

These are just some of the most important muscles for personal trainers to know. I encourage you to keep learning and mastering your craft!

It will help you become more confident in your ability to coach your clients, and they will notice that!

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About The Author

Adam McCluskey

Doctor of Physical Therapy Candidate, Corrective Exercise Specialist, Certified Personal Trainer