Strong Core for a Healthy Spine
One of the biggest buzz words in the physical therapy community over the past decade is “core.” There are some who feel it is overused, but I disagree. Having a strong and balanced core goes a long way in preventing low back pain and pelvic dysfunction, among other ailments. The core is a lot more complex than most people think. It is broken up into local and global musculature. The global muscles consist mainly of the obliques and the rectus abdominis (six pack musculature). These provide stability for spinal flexion and extension, but little control for local spinal segments. Local muscles consist of the multifidi, transverse abdominis, deep fibers of the psoas, deep fibers of the quadratus, internal obliques, pelvic floor muscles, diaphragm, and even the vocal cords (research done by Massery). These muscles provide local stability and control, preventing shearing forces in the spine.
The key is for these muscles to be balanced, as I highlighted earlier. During different movements the core muscles work synergistically to stabilize the spine, which is why an unbalance can lead to dysfunction. It is also extremely important to exhibit motor control, which is the coordinated use of muscles to control postural movements. Is it actually very common for someone to display a six pack yet have an extremely weak core, which will eventually lead to dysfunction and injury. If you have large muscle groups tugging on the spine without proper stabilization of local spinal segments, a significant amount of shearing can occur in the lumbar spine, causing low back pain. The best indicator of weak local/deep core muscles is to exhibit shaking during an exercise. This is because the deep muscles are unable to properly stabilize as external forces are placed on the body.
I am big on analogies when educating patients. My analogy for local/deep core musculature is as follows: imagine you pile up 20 blocks or so, one on top of the other, with nothing holding them together except for gravity. If someone were to push the blocks, they would fall right over. This is because nothing is providing local stability to hold them together. Now imagine you insert a string through each block vertically and hold the string up at the top. If someone were to push the blocks now, they wouldn’t go anywhere. This is because there is now local stability at every level, enough to endure outside forces exerted on these blocks. Think of your core in the same light. If you are extremely strong in your global musculature, but have no local stability, your spine is extremely susceptible to shearing and injury.
I encourage anyone working their core to get away from abdominal flexion exercises such as sit ups, and gravitate toward spinal stabilization exercises in which you are forced to stabilize your core as you move your upper and/or lower extremities. As I tell my patients, in today’s age YouTube is your best friend. Type in “core/spinal stabilization exercises” and there will be no shortage of great footage. As always, start with your appropriate exercise level and progress as tolerated.