This is the ability to maintain correct posture, especially during movement, of the central portion of the body (axial skeleton). Core stability not only aids the maintenance of good posture, but also provides the platform for weight transfer for all arm and leg movements. The shoulder girdle, spine and pelvic girdle all play roles in effective stability.
CORE FUNCTIONS The core relies on muscular control to stabilise it, as well as to control movement. The core is like a cylinder, with the diaphragm at the top, the pelvic floor at the bottom, vertebral column muscles at the back and abdominal wall muscles at the front and oblique’s at the side. This creates a pressurised cylinder in the abdomen which helps to stabilise the area helping to maintain neutral spine. As the core and pelvic floor muscles are under constant control they are predominately made up of type I, slow twitch, fibers.
Basic components of the core
The anterior and posterior core muscles
Core Muscle Layers
There are many muscles associated with the ‘core’. In this section the muscles will be broken down into:
These muscles work together to gather information on the position of the spine and surrounding muscles through muscle spindles. The trunk muscles support the torso and lumbar vertebrae along with aiding in weight/force transfer to provide a stable platform for the core hip muscles to produce movement. Additional passive support is given to the core muscles from intervertebral discs and ligaments that run the length of the spine.
Deep Stabilising Muscles
There are 3 main muscles that make up this layer:
These are small deep muscles found between the spinous and transverse processes of vertebrae. These muscles act as postural muscles as their main role is to stabilise adjacent vertebrae and control spinal movement.
Core Trunk Muscles
These muscles found in the torso are responsible for movement of the spine, allowing weight transfer between limbs and stabilising the lumbar spine. Muscles include:
The 2 main stabiliser muscles are the transversus abdominis (TVA) which acts like a corset beneath the rectus abdominis, and the quadratus lumborum (QL) which supports the lumbar spine and the pelvis.
Core Hip Muscles
These muscles create movement of the lower limbs but also play a large role in hip and lumbar spine stabilisation. These muscles include:
The thoracolumber fascia is a diamond shaped sheath located in the lower back. It not only provides stability, acting as an anchor point for muscles, it is also important in movement as it connects the hips, pelvis, lumbar spine, thoracic spine and arms via the latissimus dorsi.
The sheath is comprised of strong fibers which also allow a degree of flexibility; this enables the thoracolumber fascia to assist in transmitting forces through the torso.
The pelvic floor is made up of the muscle fibers of the levator ani and the coccygeus, these muscles sit between the public bone and the coccyx. The pelvic floor has several functions: