There are several different muscle groups that make up your abdominal muscles, or your core. The importance of these muscles is to contain your internal organs, connect your ribcage and upper torso to your pelvis, allow for a wide range of movements, and stabilize your low back and pelvis. There are four major muscle groups that make up your core: the rectus abdominis, the internal obliques, the external obliques and the transverse abdominis. The rectus abdominis runs vertically from the bottom of your rib cage to the pubic bone. It is divided into two rows, one on each side of your belly button. A thick connective tissue called the linea alba connects the two halves of this muscle. The external obliques run diagonally from the bottom of the rib cage (as well as portions from the serratus anterior and latisimis dorsi) to the top of the iliac crest (hip bone), inguinal ligament and pubic bone. The internal oblique muscles run diagonally, perpendicular to the external obliques. They attach from the thoracolumbar fascia and iliac crest to the bottom of the rib cage. These two sets of oblique muscles have tendinous portions that wrap around the rectus abdominus and into the linea alba. The transverse abdominis runs horizontally around the body connecting into the lumbodorsal fascia in the low back (this attaches into the sacrum, lumbar vertebrae and the posterolateral aspect of the iliac crest). This muscle also attaches into cartilage of the lower six ribs, the top of the iliac crest and into a portion of the inguinal ligament in the front of the pelvis. The transverse abdominis also wraps around the rectus abdominis muscle and contributes to the connective tissue that makes up the linea alba. For a great visual of these muscles, check out this image.
The most important muscle of these core muscles is the transverse abdominis muscle. It is the deepest of the core muscles and acts like a built in weight belt or corset. The action of the muscle is to pull the belly button to the spine. This action increases intra-abdominal pressure, which helps decreases vertical pressure on the intervertebral disks by converting more of the vertical force to hoop force. Transverse abdominis activation also increases low back stiffness to protect against excess movement between vertebrae that may damage the intervertebral disks or cause inflammation and spasms. This muscle is vital in stabilizing the pelvis and low back as well as allowing for maximal efficiency and power during use of the upper and lower extremities. A toned transverse abdominis will naturally activate or contract before movement of the upper or lower extremities. This helps to stabilize the pelvis and low back and protect the vertebrae and intervertebral disks. In some one with a weak transverse abdominis, the activation of the core occurs after the movement of the extremeties. This puts the vertebrae, intervertebral disks, and other supporting musculature at risk for injury. The transverse abdominis muscle works in tandem with the multifidi muscles (small muscles along the side of the spine) in the spine to stabilize and protect the vertebrae and the intervertebral disks while movement occurs. If one has a weak transverse abdominis it can lead to less stabilization and more reliance on the small multifidi in the back. This can cause more back pain, pelvic pain, higher chance of disk bulge or herniation, and less efficient and powerful extremity movements.
One of the most common injuries that cause a weakened core is called a Diastasis recti. This is an injury in which the two halves of the rectus abdominis have separated laterally (to the side) and have caused the linea alba to become very thin. This condition occurs because of an excessive increase in abdominal pressure from weight lifting, performing abdominal exercises incorrectly, pregnancy, excessive coughing or sneezing, etc. The outward pressure against the rectus abdominis pushes the two halves of the rectus abdominis apart as it stretches and thins out the connective tissue that makes up the linea alba. A diastasis recti injury is more likely to occur when the transverse abdominus muscles are already weak. Having a diastasis can cause many other issues. As mentioned above, the abdominal muscles, especially the transvers abdominis, stabilize the low back and pelvis. With a diastasis most if not all of this stabilization is lost. This can cause postural abnormalities, and depending on the severity of the diastasis, it can allow for the displacement of internal organs. This can affect their function and lead to things like digestive problems.
Diastasis recti injuries are most commonly found in women who have had a child. However, it is also found in children and men. Upwards of 70 percent of women develop a diastasis recti during pregnancy. Some of them will reconnect postpartum, but most will need extra help to heal. The most accurate way to identify a diastasis recti and evaluate the severity of the injury is to seek the support of a qualified individual, whether that person is a diastasis-aware physical therapist, chiropractor, or physician. There is a very simple way to do a prelimiary check for diastasis recti. While lying on your back place your fingers on the middle of your stomach pointing up or down. Then lift only your head off the floor. Pressing down very gently you will be able to feel a valley in between the two halves of the rectus abdominus. You should check at a point right below you rib cage, at your belly button and right above the pubic bone. Most women will have a diastasis that can be corrected without the use of a brace or slint. Those who measure their diastasis at a finger width of 3 (3cm) or greater will probably need the help of a brace in order to heal the diastasis.
There are several things that you can do and a few things to avoid when trying to heal a diastasis. Things that you should not do include any type of sit up, crunch, or plank. Once you have a diastasis and the connective tissue that forms the linea alba is weakened you should refrain from ever doing regular sit ups again. These cause the abdominal pressure that is built up to push outwards against the weakened connective tissue, essentially working against your goal of healing your diastasis. Never sit straight up from a lying position or do any type of pike movement. Refrain from slouching and sitting hunched back on your sacrum. This weakens you transverse abdominis and can prevent progress in healing the diastasis. Never sneeze or cough without bracing your core first. When you feel a sneeze or a cough coming on, sit or stand straight and bring your belly button to your spine, activating your transverse abdominis. This will help lessen any possible damage the sudden intense increase in abdominal pressure may have on your diastasis.
Things that you can be doing to help heal a diastasis recti include active sitting, active standing, and squats. To perform active sitting, sit in a chair that allows you to have your knees and hips bent at 90 degrees. Sit up on the front of your ischial tuberosities (sit bones) with your head over your shoulders and shoulders over your hips. Bring your feet and knees together. This is active sitting posture. From here you can contract and relax your transverse abdominis along with your breath. While you breath out, contract your transverse abdominis (bring your belly button to your spine). While you breath in, relax your transverse abdominis. Active standing is very similar, except you are standing with your feet about shoulder width apart. Stand up straight with your head over your shoulders and shoulders over your hips. Then contract and relax your transverse abdominis with your respiration like described above. Squats are a great exercise, not only for strengthening your core, but also your quadriceps, hamstrings, gluteal muscles, and pelvic floor muscles. To perform a proper squat, stand with your feet shoulder width apart and your transverse abdominis activated. Then maintain transverse abdominis activation the entire way down and back up. Your heels should remain on the floor for the entire squat. If you are unable to perform a complete squat, then you can use a door handle as support until you develop enough strength to perform a complete squat without support.
Though some people with a small diastasis recti may be able to heal their core injury on their own with some exercise and lifestyle changes, it is necessary for most people to seek a diastasis-aware physical therapist to help them, or to commit to a core rehabilitation program. There are many great core rehab and diastasis safe workout programs available to people working to heal their core. Dr. Dodge has worked with an excellent women’s health physical therapy specialist in the DFW area – let him know if you’d like a referral.
Here are a few options for healing and protecting the core online:
Tupler Technique – The Tupler Technique is a program designed specifically for strengthening the transverse muscles, bringing the separated abdominal muscles back together, and healing diastasis. https://diastasisrehab.com/
The Tummy Team – The Tummy Team is a comprehensive physical therapy resource, focused on healing diastasis recti, restoring alignment and posture, and core-friendly fitness. The Core Foundation program works to restore the core and pelvic floor muscles. https://thetummyteam.com/programs/?ap_id=DodgeFamilyChiro
Fit2B Studio – Bethany Learn from Fit2B Studio has many videos and workouts on her website designed with fitness for the whole family in mind. She has a passion for helping women restore core strength and has created many videos focused on building transverse strength. There are also downloadable information pages you can take to your trainer or other health professionals that explain what a diastasis is and how they should be caring for it to help you heal it.