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Get to know the "Core" as a Pressure System

Defining the "Core" and How it Functions as a Pressure System

When you think of the "Core", you probably envision well-defined abs and a flat stomach. You may have heard that strengthening your core can help reduce back pain, or that engaging your core muscles can prevent pain. The majority of individuals are acquainted with the idea of core strength or stability, however many people are participating in daily habits or exercise that may not be supporting the the core as it was designed to function. Recent studies suggest that the core comprises a sophisticated network of muscles that support the entire spinal column and that it's main role is to maintain and control intra-abdominal pressure.

One analogy I use to describe intra-abdominal pressure is a closed can of soda. Listed below are the primary muscle responsible for creating and regulating intra-abdominal pressure.

  • Top of the can - Tongue, Glottis and Vocal Cords

  • Bottom of can - Pelvic Floor

  • Front of the can - Transverse abdominus and Deep fibers of the Psoas

  • Back of the can - Multifidus

  • Sides of of the can - Internal Obliques and Deep Fibers of the Quadratus Lumborum

  • The Diaphragm regulates the pressure within the can

The Diaphragm and Psoas

These muscles work together to maintain intra-abdominal pressure. The diaphragm is the primary muscle responsible for maintaining proper intra-abdominal pressure. When we inhale, air fills the lungs, the diaphragm contracts and moves

downwards. Pressure increases in the abdominal cavity. Simultaneously, a lengthening contraction of the abdominal and pelvic floor muscles occurs. This provides dynamic stability to the spine. By stiffening the spine, the arms and legs are given a stable base to move from. If the diaphragm does not contract optimally and depress during inspiration, the pressure will not reach down to the lower lumbar spine. Other muscles may have to overcompensate for this lack of stability.

The inability for the diaphragm to contract and legthen optimally can be related to a number of factors including

  • tension and or fascial restrictions in the pelvic floor, diaphragm, chest cavity or the abdominal region

  • breath holding and/or postural holding patterns

  • lack of mobility of the visceral organs or the surrounding fascia

  • stress or emotional tension

  • habitual posture or adverse movements

The Pelvic Floor

Posture is important

The alignment of the body is critical to accessing the pressure system whether you are standing, sitting or performing a functional task. The muscles that comprise the pressure system have a very small range to function effectively. If muscles are too long or short, they have a difficult time generating force. Efficient posture allows for the muscles creating the pressure system to maintain an ideal length/tension ratio.

There are numerous methods to teach optimal posture, but I gravitate towards orienting a person to the alignment of the rib cage and the pelvis. The rib cage needs to be stacked right over the pelvis to allow for optimal pressure to occur as if the diphragm was a hat placed over the abdominal contents. Posture that relies on holding the body rigid or gripping through the abdominal muscles is not advised as it limits breathing and can create more tension and even pain in the body. Joint, myofascial, visceral, and neurovascular mechanical restrictions often prevent the ability to achieve this stacked alignment. Specific manual therapy is a wonderful option to a help the body balance tension and restore posture.

My Top 3 Core Exercises to Enhance Awareness and Activation of the Pressure System

1.The Abdominal Series (push, pull cross)

*exercise credit to the Institute of Physical Art

  • Lie comfortably on the back with a pillow under the neck

  • Slowly bring on leg at a time to the 90/90 position

  • Place hands to the front of the thighs and begin to slowly add gentle resistance directed towards the ceiling

  • No movement should occur in the body and the intention is to hold

  • Feel the response in the core slowly spread from the pelvis, abdomen, front of the ribs and the throat

  • Maintain the tongue resting on the roof of the mouth

  • Breathe!

  • Hold for 30-45 seconds or until full trunk integration

  • Cross arms and place opposite hand to the inside of the opposite knee

  • Slowly build gentle pressure towards the ceiling

  • Again, no movement should occur as the contraction slowly builds and the intention is to hold

  • Feel the spread through the entire core, pelvis, rib cage and the front of the neck

  • Breathe

  • Tongues rests on the roof of the mouth

  • Maintain the hold for 30-45 seconds or until full trunk integration

  • Bring hands to below the knees

  • Slowly begin to add resistance back towards the face

  • Feel the response in the lower back and hips

  • Intention is to hold vs push

  • Breathe

  • Hold position for 30-45 seconds or until full trunk integration

  • The body will feel like a connected and solid unit

**Lastly, repeat step #1 to full core integration

2. Prone Hip Extension or Ballerina

*exercise credit to the Institute of Physical Art

  • Lie on belly with pillow placed under the abdomen, forehead resting on the forehead

  • Relax the entire body, especially the rib cage, head and lower back

  • Press the toes of one foot to the floor and slowly extend the knee off of the ground

  • Focus on elongation of the leg out vs up and fully straighten the knee

  • Try to keep the pelvis completely stable

  • Hold this position as you feel the contraction spread from the leg to the glute. The abdomen, rib cage, chest and head and arms all press down into the floor

  • Breathe and keep the tongue on the roof of the mouth

  • Hold 30-45 seconds to core integration

  • Try lifting the leg for more load to challenge the pressure system

  • Set up the proper activation by performing the first step as outlined above

  • Slowly lift the leg, keeping the intention of elongation

  • Maintain the connection with the glute of the lifting leg as well as the entire pressure system

  • Feel the abdomen, rib cage, hands and head press down gently into the floor

  • The pelvis and spine should not move

  • Breathe!

  • Hold 30-45 seconds

3. Prone Posterior Depression of the Scapula

*exercise credit to the Institute of Physical Art

  • Lie face down with a pillow under the belly and a rolled towel under the forehead

  • Palms face downwards

  • Relax the entire body of the floor

  • Slowly start bringing the shoulder blades down and together while simultaneously externally rotating the arms

  • This will feel like the thumbs are rotating backwards and and the pinkys are rotating forwards.

  • Pay attention to keeping the rib cage anchored down, the chin tucked and tongue resting on the roof of the mouth

  • Breathe

  • Hold 30-45 seconds until full trunk integration

Try these exercises every day for one week and notice if tension and/or discomfort in the body shifts. Movement could become a bit more easeful and the body may feel looser overall.

Please reach out with questions or to book an appointment for expert movement instruction and manual therapy to help you access your pressure system!

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