Many women after pregnancy deal with an impairment known as diastasis recti abdominis (DRA) where the vertical midline (linea alba) of the abdominal muscles separates excessively during pregnancy and doesn’t return to a normal range afterward. This can happen for reasons other than pregnancy in both men and women, but pregnancy is the most common cause.
The presence of DRA can be problematic because the abdominal muscles are unable to support the body and internal organs effectively. It may also be correlated with other common conditions that occur following pregnancy such as pelvic pain and urinary incontinence.
Unfortunately there has been very little research done on how to decrease the width of a DRA. Very extreme cases can be surgically repaired, but for the majority of individuals with DRA an exercise regime is recommended. Until recently it was believed that “drawing-in” exercises for the transverse abdominis muscle were the best option for treating DRA, and that abdominal crunches should always be avoided.
Researchers like Mota et al have since shown that drawing-in exercises, while extremely helpful in other cases, actually cause the width of a DRA to widen and that abdominal crunches are very effective in creating an immediate narrowing of the gap between the rectus muscles. The assumption is that over time this repeated narrowing during exercise will lead to a sustained narrowing.
This presents a dilemma because abdominal crunches can be stressful to the low back and may worsen another common postpartum condition known as pelvic organ prolapse (POP). This involves a drop of the lower abdominal contents due to weakening of the pelvic muscles and connective tissues, which can be extremely uncomfortable and cause a variety of other issues.
So what is the answer? It may be that neither drawing-in exercises or abdominal crunches are appropriate in some cases, and it may even be that pain and function can improve regardless of the width of a DRA. As always, treatment needs to be tailored to the individual. A woman seeking to prevent or treat these conditions should seek guidance from a physical therapist who specializes in women’s health. There is also a wealth of information and resources offered online from well-renowned professionals in the field such as Diane Lee and Janet Hulme.
The following link will allow you to hear from Diane Lee in a casual interview: http://pilatesbridge.com/get-rid-of-mommy-tummy/
“Pelvic Floor Pilates”, a form of Pilates tailored to abdominal & pelvic health: http://www.pfilates.com/2010/03/what-the-hell-is-pfilates/
Reference
Mota P, Pascoal AG, Carita AI, Bo K. The immediate effects on inter-rectus distance of abdominal crunch and drawing-in exercises during pregnancy and the postpartum period. J Orthop Sports Phys Ther 2015;45(10):781-788.