What’s the #1 Muscle Anyone with Back Pain Needs to Learn About?

In this post: The internal obliques help us rotate, bend to the side, and bend forward. But, their ability to eliminate back and hip pain is why you’ll love them!

a pin with a drawing of the internal obliques abdominal muscle

When people think of their abdominals, they normally think of the rectus abdominis. This glamour muscle gets all the attention because it’s the most visible of the four abdominal muscles. After all, who among us doesn’t love some good six-pack abs?

However, if you have back or hip pain, the abdominal muscles that you want to focus on are the external and internal obliques.

The two oblique muscles help you rotate your spine, bend straight to the side, and bend forward. But the most important thing these muscles do is control your body’s relationship between your rib cage and your pelvis.

For many people, getting the ribs and hips aligned is the key to eliminating back or hip pain!

Here’s more about the internal obliques, how to keep them healthy, and why these muscles should be your new obsession if you’re currently suffering from back or hip pain.

Where Are the Internal Obliques?

The Origin

The origin for the anterior division of the internal oblique is on the lateral two-thirds of inguinal ligament and the anterior one-third of the middle line of the iliac crest.

I know. That was a whole lot of medical jargon. Here’s how you can find the origin for your internal obliques yourself.

Take your pointer finger and put it on your pubic bone (that bone right in the middle of your crotch). This is where the origin starts. Feel the bony structure of your pelvis as your fingertips make their way toward the front of your hips. That whole line that you traced is the origin of the anterior internal oblique.

a drawing of the internal obliques abdominal muscles
Thanks to Kenhub for the image.

Now, let your fingertips continue up the bony seam of your hips until you come to your spine. This is the origin for the lateral division of the internal obliques. Flash Anatomy Flashcards refers to this as the “middle one-third of the iliac crest on the middle line and thoracolumbar fascia.”

The Insertion

The insertion of the anterior division of the internal oblique is on the crest of the pubis and the linea alba.

So, think of it this way, you have your muscle origin along the perimeter and the muscle moves toward the center of your body to insert. Therefore, you have a short bit of muscle going from the pubic bone to the midline of your body, the crest of the pubis, in this case.

Further up, you have muscle from the front of your pelvis moving on a slight upward angle again, toward the midline of your body. In this case, the muscle is moving toward the linea alba, which is the middle line of your rectus abdominis. It’s the vertical line that divides your three-pack into a six-pack.

The insertion of the lateral division of the internal oblique is on the inferior borders of the 10th, 11th, and 12th ribs. This means that it inserts on the bottom edge of your bottom three ribs.

What Do They Do?

When either division of the internal obliques acts unilaterally (meaning one side works at a time), it rotates the trunk to the same side as the active muscle and/or laterally flexes the trunk toward the working muscle.

So, let’s say only your right internal oblique is working; your torso can rotate to the right and/or bend to the right.

When either division of your internal obliques works bilaterally, it flexes the vertebral column to bring your chest toward your pelvis (like when you do a crunch).

Additionally, the anterior division of the internal oblique supports and compresses the abdominal viscera. This support fights against the forces of gravity, which are constantly trying to crumple us.

Because of its role in keeping us upright and fighting gravity, the internal obliques are part of our “core” muscles.

But What If They Don’t Work…

When the internal obliques are tight or weak, the most common issue is lumbar spine (lower back) injury. This could mean a simple shift out of place that is fixed by a quick trip to a chiropractor, but it could mean something worse.

Back injuries can become very serious quickly. For example, if you think your low back is out a little and try to adjust yourself, you could make matters much worse. In fact, the wrong move could make you a great candidate for surgery or, worse yet, permanent paralysis.

I highly recommend you consult your doctor if you have back pain. Your doctor can order the appropriate imaging, therapy, and medication to correctly treat your issue.

That being said, sometimes you might notice small, correctable issues. Maybe you can rotate or bend really well to one side and not the other. You can probably do exercises to correct this imbalance. Again, though, let me remind you that if you feel pain, you need to call your doctor.

How to Keep Your Internal Obliques Healthy

In order to keep your muscles healthy, you need to do the opposite of the muscle’s movement to restore or maintain health for that muscle. Because the internal obliques allow us to flex and rotate toward the working internal oblique, we should just make sure to do the other side, too. This way, we can flex and rotate the opposite way.

What this results in is lots of twisting and side flexion. Because this muscle’s tightness and weakness often lead to lumbar spine injuries, make sure to be especially mindful and focused while performing these exercises.

Some of the best exercises to simultaneously stretch and strengthen the internal obliques by rotating or flexing to the side are:

The internal obliques can also get quite a workout without rotation or side flexion. Here are my favorite oblique-strengthening exercises that involve spinal flexion:

To Learn More…

I consulted [easyazon_link identifier=”1623170206″ locale=”US” tag=”custpilandyog-20″]The Concise Book of Muscles[/easyazon_link] by Chris Jarmey. Recently, the book was revised and is in its third edition.

Also, I consulted my [easyazon_link identifier=”1878576003″ locale=”US” tag=”custpilandyog-20″]Flash Anatomy Muscles Flash Cards[/easyazon_link]. If you really enjoy anatomy and want a tool to help you locate specific muscles correctly, I highly recommend these flash cards. I turn to them any time a client comes in with pain.

Also, Kenhub.com is a great resource to learn anatomy. Here is the link to their information about the anterior abdominal muscles (such as the internal obliques).

What is your favorite way to work your internal obliques? Let us know in the comments below.

About Sarah Stockett

Hi, I'm Sarah! After experimenting with the very best and easiest ways to relieve hip + back pain, I figured out a powerful combination of exercises to ditch pain and get back to living a completely active life. Are you ready to get started?