Transverse Abdominis in Yoga - Anatomy of Muscles
The last of the four abdominal muscles to discuss is the transverse abdominis. Use of your transverse abdominis in yoga is key to a healthy spine and ease with fun arm balances and transitions. It is the deepest of your four abdominal muscles. That means it is the one closest to your internal organs. When contracted, it supports your spine and increases pressure on your abdominal cavity to stimulate your internal organs. It also increases pressure on your thoracic cavity (where your lungs are) to aid in breathing and heart stimulation.
Origin(s) =Iliac crest (the top part of the pelvic bone); the fascia or connective tissue in the mid and low back area; the front parts of the 6th through 12th ribs; and the inguinal ligament (a ligament in the groin region).
Insertion(s) =The middle of the abdomen (specifically the linea alba (the tendinous tissue that runs down along the center of the abdomen)).
As you can note in the image to the right, the fibers of the transverse abdominis run transversely (hence the muscle's name). With a concentric contraction the insertion moves towards the origin. (See What Muscles Work in Yoga) When your transverse abdominis contracts, your linea alba (the center of your abdomen) moves in towards the center of your body. The transverse abdominis is often referred to as the “corset” muscle. Just like a corset, the muscle cinches the waistline and provides supportive pressure on your spine. When your instructor tells you to “pull the pit of your belly into your spine”, she encourages activation of the transverse abdominis.
The transverse abdominis is often the most underutilized of the four abdominal muscles. When well defined, the rectus abdominis is responsible for your "six pack" and the internal and external obliques provide contour through your sidebodies. Activation of your transverse abdominis in yoga (and any other activity) is what flattens your belly. As discussed in previous blog posts, the rectus abdominis, external obliques, and internal obliques play an active role in moving the spine. Therefore, through general activity a person frequently activates those three muscles. It is nearly impossible to even roll over in bed, let along participate in a yoga class, without using them. It is a bit easier to move while neglecting the use of your transverse abdominis.
So why, other than for a flat belly, should you strengthen your transverse abdominis? Why bother to practice isolating this muscle? Moving your body without contracting your transverse abdominis would be equivalent to throwing your smart phone or tablet on the ground without a case on it. It is possible that the phone will be ok, but there is a high risk that it will crack. When you move your spine without the protection of an activated transverse abdomins, you have a high risk of injuring your back.
The transverse abdominis in yoga practice is the key muscle for Uddiyana Bandha (the ‘flying up lock’). In order for your abdomen and diaphragm to "fly you’re your abdomen must first move in. Remember that when your transverse abdominis contracts, the linea alba (the center of the abdomen) moves in towards the center of your body, closer to your abdominal organs. The pressure of your contracted transverse abdominis provides stimulation to your internal organs and pushes them upwards towards your diaphragm. Your diaphragm is then pushed up and everything feels "locked". In an advanced yoga practice, students are able to incorporate Uddiyanan Bandha into active poses such as downward facing dog. The "corset" muscle turns on and pulls the abdomen up and in. This provides significant stability to the spine.
A stable object moves with less resistance than an unstable object. You will find more ease when you engage your transverse abdominis in yoga transitions such as jumping from down dog to forward fold or handstand because you will have decreased resistance. This is one of the tricks of those gravity defying arm balances.
The transverse abdominis is a large muscle with an important role. It is the primary "core" muscle. Yogis should pay particular attention to the building strength and control of the transverse abdominis throughout their practice and also during everyday activities such as getting out of bed and walking.
Trish Corley is a Baptiste certified yoga teacher and a licensed doctor of physical therapy.
Trish leads several Baptiste inspired and anatomy related workshops and yoga teacher trainings.