Core Strengthening in Yoga part 3

So we have talked at length about the importance of finding and engaging the deepest abdominal muscle and pelvic floor muscles in Part 1, and we have discussed the role of the other abdominal muscles in Part 2. In this segment, we will talk about the other muscles of the core, and how everything must be balanced in order to keep the spine/lower back healthy and in order to move efficiently.

The major core muscles include the muscles that we have discussed in Parts 1 & 2, in addition to the quadratus lumborum, the erector spinae, the multifidus, and the diaphragm. The first three groups are considered back muscles, although the quadratus lumborum (QL) is technically an abdominal muscle! The QL is so deep in there that when it is overly tight/strained it is a common cause of lower back pain, which we will talk more about shortly.

The multifidus works with the transverse abdominis and the pelvic floor muscles to stabilize the spine. We see a trend here- a LOT of muscles are used to support the spine because keeping the spine in proper alignment is extremely important. The erector spinae runs the length of the back and is responsible for extending the spine, laterally flexing the spine, and also provides an additional layer of muscular support. In fact, it is important that the abdominal and backside muscles of the trunk are balanced; many physiotherapists conclude that weak lower back muscles not weak abdominals are actually the most common cause of lower back pain. And weak back muscles are increasingly common as many of us spend a good deal of time sitting, and eventually all this sitting and the effects of gravity cause us to slump forward more which means the muscles of the back body are not engaged. Also, over aggressively training the abdominals but neglecting to strengthen the posterior chain can create the same rounded forward posture as sitting slouched over a computer or steering wheel, so in yoga we always emphasize a practice meant to bring the body back into balance.

The function of the diaphragm is a bit different- it is the breathing muscle; when the muscle contracts air enters the lungs via a vacuum effect, and when it relaxes, the lungs are compressed and we exhale. The diaphragm is also involved in generating the pressure needed to cough and vomit.

In addition to these major core muscles, several other trunk muscles comprise the core. These are the minor core muscles and include the gluteus maximus, the latissimus dorsi, the trapezius, and the iliopsoas. The latissimus dorsi and the trapezius help stabilize the spine while the arms and shoulders move. In addition to this, I believe that the gluteus medius and gluteus minimus deserve an honorable mention because they are important for holding the pelvis steady during movement which minimizes torque on the spine. In fact, many instances of lower back pain (as well as knee pain) can be linked to weak or dysfunctional gluteus medius, although that will not be elaborated on in this post, as we are keeping this discussion to the muscles commonly agreed upon to comprise the core.

Being bipedal, humans have an extraordinarily large gluteus maximus, which enables us to maintain a steady upright posture while extending and laterally rotating the hip. The gluteus maximus is also intended to power the transition to standing from sitting and climbing stairs. I say “intended to” because in many people it is weakened and deactivated such that the hip flexors (and arms) actually power the move. The fact that that other muscles have to do the job of what should be the largest and strongest muscles of the body is a sign that the body is not working properly, and that in time, pain and injury are certain to occur. The iliopsoas is the largest/strongest of the aforementioned hip flexors, and allows, as the name would imply, flexion of the hip (leg move toward the front body). In other words, it acts in opposition to the gluteus maximus, which is a hip extensor (leg move toward the back body).

If the gluteus maximus is weak (a common problem), hip flexors will dominate and the pelvis will be pulled forward into an anterior tilt. This shortens and tightens the muscles of the lower back and creates an exaggerated arch or lordosis. In time, the lower back muscles become significantly shortened and tightened which leads to lower back pain.

In order to maintain a healthy lower back, all parts of the core must be strong and mobile enough so that they can support the spine and keep the pelvis in neutral alignment. This means that the pelvic floor and abdominal muscles work to support the spine and hold the front of the pelvis up, while the back muscles and the gluteus maximus (and hamstrings) provide additional support and gently pull the back of the pelvis down. This counters the downward pull of the psoas on the front of the pelvis and keeps the pelvis neutral.

However, what if either the abdominals and gluteus maximus are overly tight from an unbalanced exercise program- think sitting all day and then heading to the gym to work that sixpack and booty 😉 – and/or the psoas/hip flexors are weak? Then there is nothing to counter the abdominals and glutes/hamstrings from pulling the pelvis into a posterior tilt, which flattens the natural lumbar curve creating a lot of stress on the spinal discs.

So now that you are probably overwhelmed with anatomical information- what is the takeaway? First, that connecting to the deepest core muscles i.e. the transverse abdominis and pelvic floor first is imperative. As we said previously, anything you build on a foundation of quicksand has little hope of standing. Second, understanding that because so many parts are at play, that something as simple and common as lower back pain can be caused by a myriad of muscular imbalances and irregularities. This means that using the yogic tools of mindfulness and self-awareness to examine how your body feels and performs is imperative in order to determine the nature of your unique imbalances in order to begin to correct them.