Meet Your Abdominals!

Your abdominals are essential to every thing you do. Literally. You might not know that you have four muscles which constitute “the abdominals.” From deepest to most superficial, they are the:  transverse abdominisinternal oblique, external oblique, and rectus abdominis. I’d like to take a moment today to discuss with a little bit of detail where these muscles are and what they do.

drawing of how the four abdominal muscles interact

Transverse abdominis

We have already talked a bit about the transverse abdominis, or transversus, in my article on Pilates Breathing. The transversus is the deepest abdominal muscle. It runs from one side of your spine to the other and connects to the rib cage and pelvis. Essentially, the transversus is the muscle that holds all of your organs not protected by the rib cage or the pelvis in your body. I like to think of it as a sausage casing, holding all of the good stuff inside of us.

The transversus is only activated when you cough, sneeze, or intentionally blow air out of your mouth. I believe this is why Pilates breathing involves the exhale through pursed lips. If you can activate and tone the transversus, you can draw the internal organs more appropriately into the body cavity, helping you find relief from low back pain and helping you feel and look thinner.

Internal oblique

Bring the heels of your hands to the mid-point on your bottom ribs. Now, slide your hands out to the outside of your hips. You have just traced the anterior (front) portion of your internal obliques. If you let your thumbs press in to the muscles coming off the back part of your outside ribs, you are on the lateral (side) part of your internal oblique.

The anterior part of the internal oblique works individually to rotate the trunk the same direction as the working muscle. It also flexes the trunk to the same side as the working muscle. When both anterior internal oblique muscles work together, the muscles help to bring the chest and the pelvis toward each other. These muscles also help the transversus with forced exhalation.

The lateral part of the internal oblique works individually to rotate the trunk toward the working muscle. For example, the right lateral internal oblique will help rotate the trunk to the right. When both muscles work together, the rib cage is appropriately placed and stabilized above the pelvis.

External oblique

Bring the heels of your hands to the outer edges of your rib cage. Slide your hands so that your fingers meet at your pubic bone. You have just traced your external obliques.

Office Space's Lunbergh wearing suspendersNow, stay with me here, let’s take a look at Lumbergh (because we have already established that I love Office Space). Take a look at his suspenders. About an inch above the attachment of his suspenders to his pants is where the internal and external obliques cross.

Take a moment to imagine you have suspenders. (I’m guessing that you’re not wearing suspenders.) Place your finger tips in that spot about an inch down from your rib cage. Twist your body to the left. Can you feel the muscles work? Now, twist to the right to keep your body balanced.

The external obliques work individually to help you rotate to the side. For example, if you twist to the left, the right external oblique is working. They also work individually to help you bend to the side with no spinal rotation. If you were bending to the right side, the right external oblique would be working.

When both external obliques work together, they can flex the trunk forward like a crunch. Plus, they provide support for the lumbar spine (low back). They also help the transversus with forced exhalation.

Rectus abdominis

Are you familiar with pictures of six-pack abs? Those are the rectus abdominis. Rectus abdominis is the most superficial of the abdominal muscles. It runs from your pelvis up to your ribs in a straight band.

The rectus abdominis brings you forward (like a crunch) and also helps bend you to the side. Even though there are four abdominal muscles, the rectus is the one that will most likely try to step up and do the work. This causes disfunction. The goal is that each abdominal muscle do their own jobs. Sure, there are areas where they intersect, but if a muscle is supposed to do a certain movement, it should at least be participating.

For example, let’s look at the crunch. It’s a popular exercise, and I’ve mentioned it a couple of times in this article. When you do a crunch, it is tempting to just let the rectus abdominis do all the work. It is important to note that the rectus is not the only muscle engaged when doing a crunch. Both the internal and external obliques assist with this move, so it’s important to check in with those muscles to make sure that they are also working.

Mindfulness while moving is essential. Constantly check in with the muscles that should be working. If you find some disengagement from your muscles while doing an exercise, pause your movement, try to reconnect with the muscles you are seeking, and try again. This will become a very familiar process for you, especially if you are overcoming an injury.

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When you’re moving, are you checking for your abdominal muscles? Please let me know any comments or questions you might have below.

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Sarah Stockett is STOTT certified in Matwork, Reformer, Cadillac, Chair, & Barrels, Injuries & Special Populations, and CORE; a Yoga Alliance RYT-200; and has studied Active Isolated Stretching. When she is not trying to discover the best exercises to get rid of pain, she likes watching movies and travelling with her family.

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