What is Rectus Diastasis?

Diastasis = separation


Rectus Abdominis = a pair of long flat muscles that run from the breast bone to the pubic bone along the front of the abdomen (your six-pack muscle).

The Linea Alba or "White Line" is the name of the connective tissue that joins the left and right sides of this paired muscle. The rectus abdominis muscle is separated by connective tissue into 8 segments and joins into a thick fascia (no muscle just thin connective tissue, actually a flat tendon) about 1/3 of the way below the belly button. The connective tissue of the linea alba is made up of the lining of the lateral abdominal muscles, in layers including the internal and external obliques which make up the upper layers, and the transverse abdominis which makes up the innermost layer.

This separation of the linea alba measured with ultrasound varies with each individual woman. Most commonly a separation is diagnosed as a diastasis when 2.0cm or greater.

Learn how to check yourself for a diastasis in our article Belly or Bulge: How to tell if you have a Rectus Diastasis.

When working with a Core System Specialist, however the diagnosis of diastasis can be made when comparing your "normal" width with an "abnormal width" anywhere from 1.5 cm or greater. The prescence of a diastasis in postpartum women correlates with increased muscle weakness in both strength and endurance (24). Rectus diastasis however, is not a problem unique to women who have experienced childbirth. This is because Rectus Diastasis is not caused by stretching alone.

66% of first time mothers have a diastasis of the rectus abdominis muscle by the end of the 3rd trimester. The more children you have, a short stature (height), having multiples (twins), improper strength training and cesarean section all increase a mother's risk for a rectus diastasis (22). This separation, or stretching of the linea alba will heal on it's own during postpartum recovery in about 36% of women (24). Which means that 64% of women who experienced diastasis near the end of their pregnancy continue to have a diastasis after 8 weeks postpartum. Researchers report that women who have a diastasis lasting longer than 8 weeks postpartum, show no improvement after 6 months, 1 year or even at 5 years. Why does diastasis in some women improve when in other's it doesn't?

Rectus diastasis is a symptom of core dysfunction. The separation at the linea alba happens when the transverse abdominis is deactivated and not able to tension the interior fibers of this long line of connective tissue. The transverse abdominis can be deactivated because of direct injury to the core system, such as a hernia, surgery like a cesearean section, or fractures of the hip or spine. A woman can also teach her body not to use the transverse abdominis when experiencing prolonged pain after childbirth, surgery or an injury. Therefore, the reason that the rectus muscle heals in some women and in others it doesn't is because of an underlying problem in the core system.

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The two important measures of the severity of the diastasis is the width of the separation, and the ability or inability to create tension along the fascia of the linea alba. The tension across "the gap" is directly related to how well your core system is working.

The key to closing the gap, or correcting a diastasis is to first restore the core system, then once there is sufficient tension across the linea alba, the rectus abdominis muscle can be aligned, strengthened and the diastasis will close (sometimes not to it's original shape, but to a functional distance).

The Mommy Ready Postpartum Program was designed to restore core system function, and correct a diastasis by teaching you the correct sequence of exercises. We help you build a strong foundation of alignment, core breathing, awareness during daily movements and help you incorporate your core exercises into everyday-life activities.

See references.