Optimal Core Stability: What that really means?
Written by Danielle Bararuk | November 10, 2021
Have you ever had a sore back, hip pain or pelvic girdle pain the day after you have been strength training, running or participating in an activity? But you feel like you have a great movement pattern and great technique. Have you experienced incontinence, prolapse or rectus diastasis that did not rehab fully post-partum? What you may not be activating or utilizing properly is your Inner Core!
The term core, core stability and core strength have always been hot topics in the physiotherapy world, but also in the general public. Most of us think about strengthening the “6-pack” muscles, the rectus abdominus, when we think about strengthening our core. This is our outer core, and its primary function is to give us trunk movement and overall stability. However, our inner core is what stabilizes our trunk, it mechanically stabilizes our spine and takes pressure off our back. In this blog I will talk about what muscles make up the inner core, what prevents it from working properly, and ways we can rehab and strengthen it.
The Inner Core. If you think about the inner core as a cylinder or soup can, the top of the cylinder would be the diaphragm and the pelvic floor muscles would make up the bottom. The diaphragm (our primary muscle of breathing) needs to be aligned over top of the pelvic floor muscles for the system to work optimally. There is transverse abdominis which wraps horizontally around our tummy, like the middle of a can, and is the deepest layer of the abdominal tissue. Lastly the multifidus runs up the back and contributes to the overall stability of the core. In proper alignment when you take a breath in, the diaphragm moves down. This moves the pressure in your abdomen, called the intraabdominal pressure, downward. When the pressure moves downward, it elastically loads the pelvic floor muscles that are situated below and the transverse abdominus muscles in the middle. When you breath out, the diaphragm relaxes and moves back up and the pelvic floor and transverse abdominus recoil. This team of muscles is meant to be a dynamic system, moving like a piston in a shaft, and the muscles are meant to contract and relax. Optimal core stability is achieved through the interchange of the pressures within the system, via our breath, and muscular forces at the correct period. Just like a soup can, if there is a defect or dint in the can somewhere, the whole can will not be as stable. If we have a dysfunction in one of these muscles or they are not recruited properly, it will impact the overall stability of our core. We will talk about the dysfunctions next.
Dysfunctions and the Inner Core. If we have poor posture, altered breathing mechanics ie. breath holding, abdominal gripping ie. tightening our tummy muscles (squeezing the middle of the cylinder) and or tense or weak pelvic floor muscles, we can end up with back pain, hip pain, pelvic pain, urinary leakage (incontinence), prolapse or pressure in the pelvis, coning or straining on the abdominal muscles and the list goes on. The inner core is not contracting and relaxing properly to control the pressures that act to stabilize the spine properly during movement. Let’s talk about posture, altered breathing mechanics, abdominal gripping and weak or tense pelvic floor muscles, and how they lead to dysfunction in the system.
Postural Alignment. In optimal postural alignment, our rib cage should be in the neutral position. The bottom of the rib cage should not be lifted to the front, not tilted too far to the back, and not positioned in front of or behind our pelvis. If we stand with an increased curve in our low back and our chest high it will cause us to lift the bottom of our rib cage up, like a “bell rung up” position. This will cause you to lift your rib cage when you take a breath in, instead of allowing our diaphragm to descend and expand our lower rib cage out like an umbrella. Also, if we stand with pelvis positioned in front of us, our diaphragm will be positioned behind our pelvic floor and will not be able to load it with an inhale. It does not matter how strong the inner core is if it is not in the correct alignment to even engage it!
Breath Holding. Sometimes we hold our breath during movement or when we are lifting something heavy to give us stability so we can complete the task. Imagine your inner core as a balloon. You fill the balloon with air, keep the air in the balloon while squeeze it. The compressed air in the balloon presses out on the walls of the balloon under pressure. Eventually if the load on the outside of the balloon is too much, the balloon may not be able to sustain the load. Just like your inner core. When you take a deep breath in and then you hold your breath while lifting an object or applying a load to your body, your inner core muscles may not be able to tolerate the intraabdominal pressure plus the pressure of the external force, ie. The box you are lifting. This increase pressure on the muscles of the inner core can cause strain or injury to them. It can also cause excess pressure on your pelvic floor muscles and increase pelvic health symptoms, ie. cause leakage, increased prolapse or pressure on your rectus diastasis.
Abdominal gripping or tension in the abdominals. When we do not activate our inner core properly, we will adapt different ways to gain core stability. One way people do this is by gripping or tightening their outer core, ie. Rectus abdominus. If you think about a balloon as your inner core, and if you squeeze the balloon in the middle, it will put increased pressure at the top and at the bottom of the balloon. Just like your inner core, if you tighten your abdominal muscles, it will increase the pressure on your diaphragm, not allowing it to descend and put added pressure down on your pelvic floor. This can again increase symptoms of incontinence, prolapse, rectus diastasis and so on.
Tension in the pelvic floor. If the pelvic floor muscles are tight they will not lengthen when the diaphragm descends. This will prevent the interchange of pressure and the overall mechanical stabilization of the spine and core. If we do not have all parts of the inner core functioning properly, we will not have stability and can end up with injury or increased symptoms.
We need to achieve optimal postural alignment, a proper breathing method, strengthen our inner core muscles, learn how and when to engage them, and then put that all into action during functional movement! If you are rehabilitating your core after baby, returning to work or activity after a back injury, preparing for baby to come, or just want to increase your overall health a pelvic health physiotherapist can help you achieve your optimal inner core function.
By training your inner core you won’t get the 6-pack physique, but it will prevent you from sustaining injuries, rehabilitate your pelvic health dysfunction and keep you participating in the activities that you enjoy!
Danielle Bararuk
Physiotherapist
Pelvic Health Therapist
