Internal & External Obliques

(Let's start exploring muscles from outside to inside!)

Linea Alba

The Linea Alba is a long piece of connective tissue (referred to as a fibrous raphe) which runs from the Xiphoid Process (Zai-Phoid) to to the Pubic Symphysis. This tissue is formed from and a major player in abdominal muscles and their function. That Xiphoid process is the bottom-most portion of your sternum (breast bone).

For our first body exploration we will start with our fingers laying on top of our sternum and slowly word downwards, staying in the middle of our bodies, past that final section (Xiphoid Process) and slowly into the abdomen. Try and keep on the midline as you slowly move your fingers in circles, or side to side.

Go down as far as comfortable - this line ends on your Pubic Symphysis, so if you're in a public space you may need to go somewhere more secluded! This slow work is beneficial before any core workout, or at the end of the day while you lay in bed trying to sleep. Once you've explored your Linea Alba enough, move onto the next section - the External Oblique!

External Oblique

Left Image: Front view of muscle | Right Image: side-view of muscle

Shown above the External Oblique is a muscle laying superficial (near the surface) of the abdomen. You have one on each side, though the above images only show the left side muscle. This external oblique attaches into the Linea Alba, the pubic crest (lower down), to the Anterior Superior Iliac Spine (ASIS) and the Iliac Crest both on the pelvic bone. From the side view you can see the muscle tissue also connects up into the ribs at the side, and just below the larger Pectoralis Major muscle at the chest. It connects to ribs 5-12.

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For Body Exploration of this muscle let's focus on self-massage first, then move into some light movements. Nothing during this exploration should hurt - though you may feel discomfort on movement if you have not done this in a while! As always, if you have questions or are in pain please reach out!

Starting with the Linea Alba we will focus on following the midline up and down, lightly, with our fingers and palm. From here at any time along this connective tissue start to move to one side (doesn't matter which, you have an external oblique on both sides!). Take note in the images above on how the fiber orientation is and work either with that, or against it. For the External Obliques the fiber orientation is at an angle, so try and follow that.

Don't worry about feeling anything specific - just take note of how your tissue feels and slowly engage the skin. For added feedback try replicating some of the motions above (or see the video attached and copy those!). When you are ready move onto the next section - all about the Internal Obliques!

Internal Oblique

Left Image: Front view of muscle | Right Image: side-view of muscle

Shown above the Internal Oblique a muscle laying deeper (under) the External Oblique muscle. This tissue still attaches into the Linea Alba, that midline tissue, but also attaches to what is called the thoracolumbar fascia - a thick band of connective tissue across the lower back. In addition to this it also attaches to the anterior (front) two-thirds of the Iliac Crest (pelvic bone), the lateral (away from the midline) two-thirds of the Inguinal Ligament (this ligament runs from the ASIS to the Pubic Tubercle). As you can see via the side view it also attaches into some of the ribs, notably the 10th-12th.

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Body Exploration for the Internal Oblique will involve some movement and breathing. I suggest once again starting on the Linea Alba, anywhere will be fine. From here follow along with how the tissue fibers are orientated (check the above images, or view the video!). We want to make sure to bring our hands around the sides, almost to the low back - which might involve using the opposite hand for better reach. Again, slowly move your fingers in circles and engage the skin.

During this time, incorporate the different involvements of the muscles - rotate your torso to the same side (so, if your hand is over the left internal oblique, you'd move your torso to the left. Same with lateral flexion (sidebending). Can you get a better sense of the tissue moving with touch? Can you try and differentiate the External and Internal Obliques from eachother? Try their motions with hands placed over them.

Finally take the rest of your time this week to incorporate what you've learned about these muscles into your daily routines. What things do you do during the day that these structures can help with - and are they or are you using other things to accomplish the task? When walking around, try and actively engage these tissues - knowing where they connect now and what they do.