Why I don’t use term “Core” or “Core Stability”. Should we stop using the term “core” all together, especially when discussing back pain?
The words we use to describe certain areas of the body should be used to help explain not to confuse, it seems that over the past decade and more recently people have had a very strange understanding of what the abdominal musculature actually does, I speculate that the term “core” has been a contributing factor to some of this confusion.
When it comes to lower back pain many people have been told from various therapists that “core weakness” is the cause of their pain. The solution they have been sold is that by “doing core stability exercises” their pain will be resolved. This is very misleading information. Firstly, my question to any therapist or trainer and the local Pilates instructor who claims core stability needs to be improved is, what do you mean by the “core”? Below is the list of some muscles which could be considered in this “core” area. Some layers are outer layers more superficial to the skin while others are far deeper closer to the spine. Yet they all play an imperative role in healthy spinal function.
- Rectus Abdominis – Spinal Flexor
- External Oblique – Contralateral longitudinal rotator, lateral flexor
- Internal Oblique – Ipsilateral longitudinal rotator, lateral flexor
- Upper Transverse Abdominis – Contralateral longitudinal rotator
- Lower Transverse Abdominis – Ipsilateral longitudinal rotator
- Psoas Minor – Spinal flexor, Ipsilateral longitudinal rotator, lateral flexor
- Psoas Major – Hip flexor, spinal flexor, ipsilateral flexor
- Quadratus Lumborum – lateral flexor, spinal extensor
- Iliocostalis Lumborum – Spinal extensor, ipsilateral rotator, lateral flexor
- Multifidus Lumborum – Spinal extensor, contralateral rotator, lateral flexor
- Longissimus Lumborum – Spinal extensor, ipsilateral rotator, lateral flexor
These are just to name a few, but there are many more muscles with different combinations of actions which also help stabilize the spine. When a patient or client is being prescribed a few non-specific exercises to strengthen musculature around the abdomen, can they really target what they think may be weak? The elephant in the room is, how do they infer that “the core” is weak in the first place? What diagnostic tools have they available to deduce deficits in strength past the typical postural analysis and movement screen?
If one considers the anatomy and architecture of the spine there is no real core, we have a spine with an abundance of muscles which uniquely operate around it. Each and every muscle has a role in movement. To do this they generate specific forces to create and also to allow controlled motion. Our spine is a multi-planar, multi-axial structure combined with muscles and ligaments which essentially create a three-dimensional system where a variety of tissues control the body in space. The notion of a central “core” as described by many therapists and exercise gurus doesn’t really fit in the anatomical understanding of how the spine operates as shown in medical literature.
We must discard the idea of a “core” and replace it with an inference that the spine is a three-dimensional movement system which encompasses a variety of components that provide the necessities of human kinesiology. This system can make specific calculations instantaneously, one example would be by simultaneously providing controlled motion and intra-abdominal pressure; furthermore, in high load situations by providing the co-activation of muscles to generate adequate stability all while being precisely orchestrated by a brilliant motor control system, known as the central nervous system.
The mainstream notion of strengthening your abdominal musculature is not without merit, however it has led to a ‘fad’ in the industry that a “stiffer and stronger core” is better, whereby remedying spinal weaknesses will remedy your lower back pain is sadly unfounded. Again, how do they determine the musculature is weak and needs intervening upon? How do they determine if said intervention has improved strength? There are numerous reasons why the spine may be causing pain. For now, setting aside the non-mechanical factors, any mechanical dysfunction from the foot through the upper spine, including the arms can be an indirect result of why you may be having lower back pain, which have zero direct local contributing factors to the actual spine itself. When one studies the movement patterns of humans, the whole system has to work together, unfortunately when one area of this biomechanical system becomes dysfunctional, it then requires other functional areas to become overactive which in many cases results in pain. For example, your foot and ankle have 54 joints, each joint is designed to allow a precise amount of controlled motion. If any or multiple joints in the foot are not moving properly the nature of movement requires a separate properly functioning joint to take on extra force and motion due to the deficit earlier down the chain, this results in excessive tension on the overworking muscles and ligaments. This is known as orchestrated compensation, as it is not the most optimal solution, it is however the most optimal with what the body currently has available.
We also know that many in the industry have heavily focused on “core activation” exercises which teach the patient/client to pre-tense up their core during any strenuous movement. This translates into many dysfunctional movement patterns. Your nervous system is incredibly intelligent, from the time you get up from you chair and walk into the other room, it has made millions of specific calculations on muscular recruitment patterns this is all done with zero conscious thought from the human. Pretty brilliant you might say! So why should someone “tighten up their core” during an exercise? We do know that when people tighten up their abdominal musculature they increase intra-abdominal pressure which in turn increases spinal compression, this excessive compression is one of the mechanisms for which we know can lead to spinal pain. The Idea of pre-bracing or pre-tightening of this musculature can be contraindicated on a variety of exercises not to mention the improper training of neuroplasticity. There are however a select few exercises where increasing abdominal tension can have a positive desired effect during a specific abdominal exercise, these are however few and far between. Of course, we do need spinal stability and abdominal control, however this is not to be emphasized over the need for every area of the body to be functioning properly.
When assessed appropriately, considering the numerous variables we do see people who have diminished abdominal and back strength where facilitating the motor system to better support the structures of the spine to optimally load it would be indicated. Yet the mainstream perspective where overly strengthening or overly bracing the “core muscles” by sucking the belly in, contracting their pelvic floor and hyper strengthening their back muscles for the idea of protecting themselves from an injury is just simply put ‘a bad hypothesis’ which could potentially be contraindicated for an individual’s musculoskeletal health.
Assessing the muscular system as a whole and removing the heavy emphasis on the abdominal core strength would be a good place to begin. If we can move away from the idea of ‘more is better’ and move towards a notion of ‘optimal for that individual is better’ it would follow a more consistent evidence based thought process and be far more logical from a biomechanical perspective as a whole.