When most people think of their core muscles, they think of six-pack abs and the rectus abdominis. This muscle is the most superficial layer of the abdominals and is the least important “core” muscle other than to look strong. The two most important muscles for a strong core are
the transverse abdominis (TA) and the multifidus muscle. The TA is the deepest abdominal muscle as it wraps around the abdominal cavity and attaches at the spine. It acts as your body’s corset when contracted by keeping your spine strong and stable during movements. The multifidus is the other essential spinal stabilizer as it also prevents excessive translation and movement of the spine during body movements. These muscles can be palpated and tested for functional strength by skilled physical therapists. It is difficult to determine or grade the strength of these muscles without conducting an electromyography (EMG) study, which is why they are mostly graded on the ability to maintain a neutral spine during exercise.
To begin strengthening the TA, you can start by lying down on your back with your knees bent. To contract your TA, pull your abdominals up and drawing in as if you are tightening your abdominals across your stomach like a corset. You can check yourself by feeling for a gentle tightening of your deep, lower abdominals when you feel at the inside portion of the front of your hip bone. Once you can properly contract your TA, add movement to the exercise with small marches and eventually going to straight leg raises. Once patients are able to perform these types of exercises with proper form, they will be progressed to more functional movement patterns while performing TA contractions.
What about the multifidus? Check in next week to find out how to strengthen this important muscle to treat and prevent back pain.