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3.4 Causes of OP: Poor core activation

1. Osteitis Pubis: an introduction
1.1 Symptoms and Stages of Osteitis Pubis
1.2 OP Diagnosis guide
1.25 Should I get a MRI/CT/Xray scan for OP?
2.0 Overworked Adductors: The true cause of OP
2.1 Rest: The worst treatment for OP
2.2 OP mechanics in detail
3.0 Faulty firing patterns: Weaknesses that cause OP
3.1 The Deep Front Line
3.2 Causes of OP: Weak arches
3.3 Causes of OP: Weak glutes
3.4 Causes of OP: Poor core activation
3.5 Causes of OP: Dysfunctional pelvic floor and Sacroilliac Joint
3.6 Causes of OP: Dysfunctional oblique chains
3.7 Causes of OP: The balance and coordination system

Refresh your understanding:

  • Osteitis Pubis is caused when adductors are overworked over time.

  • Your personal biomechanics (the patterns that fire your muscles/move your joints) lead to the OP mechanics (hip drop, pronation, anterior pelvic tilt, locked SIJ and knocked knees) that cause OP.

  • Your personal biomechanics must be corrected to stop overloading your adductors.

  • The Deep Front Line (DFL) is the foundation of your body, responsible for the stability and alignment of your entire body. The DFL relies on 6 biomechanical/functional systems (arches, glutes, core, SIJ/Pelvic Floor, Oblique Chains, Balance).

  • Dysfunction/lack of coordination in and between these 6 systems leads to the poor OP mechanics that cause OP.

  • By maintaining good alignment (centre of gravity) the load/force of movement can be evenly distributed across the entire length of the DFL (and therefore the body) rather than being concentrated in the adductors.

  • The arch ensures a stable foundation to your DFL. The glutes ensure that your hip (and therefore femur, the longest bone in your body) is safely secure in its socket.

  • The core’s role is to ensure the stability and alignment of the pelvis, lower spine (lumbar) and rib cage within the DFL.


The word is thrown around like you’re born understanding it, but do you really know what your ‘core’ is?

Much like the glutes the core is made up of a lot more than just your Rectus Abdominis (6 pack) or Obliques (Side abs). Depending on how technical you want to get, there are more than 20 muscles you could consider as part of your core. These can be divided into 2 distinct systems.

  1. The ‘deep core’ whose major purpose is to stabilize the spine and pelvis within the DFL and

  2. The ‘superficial core’, whose dual purpose is to  provide power in flexion (sit up motion) and rotation (twists) and to supplement the stability of the deep core in challenging movements (running, jumping, changing directions etc) where the deep core struggles to maintain DFL/COG alignment.

Let’s look at each core in greater detail.


The deep core is the most important group of muscles and fascia for stabilizing the spine and pelvis (with help from the glutes and other areas). While often mentioned it is rarely understood by people trying to use it.


The best way to think of your core is like a ‘box of stability’. Your pelvis, lumbar spine and bottom of your rib cage are extremely mobile flexible bones and joints. You can bend, twist, turn and contort your spine in almost 360˚ of motion.


Your flexible spine relies on the deep core to control this mobility. It stops you severing your spinal cord! To simplify the role of each section of the deep core, let’s break down our ‘box of stability’.


Top: Diaphragm

With every breath your diaphragm contracts. If you breathe deeply in and out this contraction will provide strength and stability to your rib cage.

Sides and back: Transverse Abdominus (and Multifidus at the spine)


The Transverse Abdominis (TA) is the lower core muscle most often referred to in Pilates. The TA wraps around your spine and stomach. It has attachments across the entire top of the pelvis. Its fascial strings attach all the way to the spine and connect to the multifidi (for simplicity consider the multifidi muscles a part of the TA). They act like the strings of a corset.


The TA contracts by sucking inwards providing increased stability as the ‘corset’ becomes tighter.

Bottom/Floor: The pelvic floor


The pelvic floor covers the entire inside of your pelvis. The pelvic floor’s broad connections allow it to control and stabilize the entire pelvis and Sacroiliac joint.

Breathing: the key to activating the Transverse Abdominus/deep core

Yoga has known this for generations; if you want a stable, centered body then breathe well. What they’re also saying is that when you breathe well you activate your core well! Your diaphragm and your TA are intricately linked. It is this co-contraction that stabilises the deep core and therefore the spine.

The simplest way to describe this is to demonstrate it (video below).

TA contraction pulls tension inwards > the diaphragm pushes pressure outwards > tension increases in TA = stable spine.

Simply put, core breathing is the only way to correctly engage your core and stabilize your lower back.

Due to its fascial connections, the TA also tenses and engages the Pelvic floor. This completes our ‘box of stability’. With activation of the top (diaphragm), sides and back (TA) and floor (Pelvic Floor) our lower rib cage, spine and pelvis is stabilized.



The diaphragm, TA (cut away in image above) and pelvic floor are all part of the DFL. With an engaged Deep Core your pelvis, spine and rib cage is securely stabilized within your DFL/COG.

Deep Core muscles = slow twitch marathon runners!

The deep core muscles are lean, skinny, slow twitch machines. Like the rest of the DFL, they lack the power to drag you into correct alignment, but they have the stamina to keep you there indefinitely. The deep core is designed to go the distance. So when you can activate your deep core by breathing effectively, every single breath stabilizes and protects your spine, keeping you aligned and safe within your DFL all day!

Their brothers, the superficial core muscles work differently.



The Superficial Core is most people’s understanding of their ‘core’. It includes the Rectus Abdominus and Oblique, the most visible core muscles.

In comparison to their ‘deep core’ brothers these muscles are thicker, faster twitch, ‘power’ muscles. They are designed to generate or stop movement. They like to fire strongly and quickly, and then get adequate time to rest and recharge before the next big effort. They are designed for power and emergency, for movement and explosion.

OP patients use Superficial core all day every day

Unfortunately this is not how OP patients use their superficial core. For OP patients their deep core is not working so they try to use their superficial core to pick up the slack. Unfortunately the obliques and 6 pack have no direct connection to the spine.

What’s more, they fatigue quickly and need rest. Simply put, your obliques and 6 pack are horribly designed and poorly positioned to provide constant stability to your spine.

This causes two distinct issues for OP patients:

  1. Insertional abdominal hernias (often called sports hernias) – constantly contracting and trying to stabilize with these muscles overloads the rectus abdominus attachment at the pubic bone, leading to constant pain or even herniation.

  2. With inadequate stability, the adductors kick in to help stabilize the spine. Leading to…… OP.



In addition to overusing your superficial core OP patients also recruit and tighten the hip flexors to help stabilize the spine. They can provide some measure of stability, but at a cost. Used this way they pull the pelvis into either an anterior tilt or sway putting extra load on your adductors.


Without proper deep core activation and stabilization we again overload and over rely on our adductors, leading to OP.

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