Theory of the core muscles

The core can be thought of as a cylinder of muscles around the inner surface of the abdomen. There are 4 main muscle groups considered:

Transversus Abdominus (TA)

• The deepest of all the abdominal muscles lying under the oblique abdominalsrectus abdominus (the 6-pack muscle).
• It is this muscle that is considered to be the corset of muscle providing stability.
• It connects to the individual vertebrae of the lower (lumbar) spine and wraps right around each side to meet in the midline of the front of the abdomen.
• When contracted it functions to both increase the pressure inside the abdomen and pull tightly on the vertebrae themselves to provide exceptional stability to the spine.

Multifidis

• This deep back muscle lies on either side of the spine and again connects to each individual lumbar vertebrae.
• It functions in extending (bending back) the spine as well as being an essential postural muscle keeping the spine upright.

Diaphragm

• The primary muscle for breathing, the domed diaphragm provides the top of the cylinder core.
• When the transversus abdominus contracts, the diaphragm tightens to maintain pressure in the abdomen and so provides stability to the spine.

Pelvic Floor

• Famous among pregnant women, the pelvic floor muscles provide a sling running from back to front, from the bottom tip of the spine (the tail bone) to the front of the pelvis.
• It contracts simultaneously with the transversus abdominus to form the bottom of the cylinder of muscles.

When all these muscles contract together they keep the spine in its most stable position (the neutral zone), and aid in preventing injury. They are known to contract prior to any limb (arm or leg) movement and so they function in keeping the centre, or core of the body rigid during all movement. Recent evidence has found that in people with low back pain these muscles fail to contract before limb movement and so the spine is vulnerable to injury. Thus retraining these muscles to contract at the right time is the fundamental theory of core stability.

Uses of core stability

Injury Prevention:

• Strengthening the core is essential to prevent all forms of injury around the lower back area.
• By training the core the rest of the muscles in the area i.e. the hamstrings, gluteals, abdominal and back muscles all work more efficiently and together.
• Risk of injury caused by over activity is reduced in any particular muscle group due to muscle imbalance.

Rehabilitation from injury:

• Core stability is an essential component of any rehabilitation program not only for low back pain, sacroiliac painGilmore’s Groinhamstring strainshoulder pain.
• By providing stability beneath the muscles that provide movement, core stability provides excellent rehabilitative properties for such injuries and is commonly used by physiotherapists

Sports Performance Enhancement:

• Whether you enjoy an occasional gym session or whether you’re an elite sports person, core stability should be part of your training regime.
• Working on your core can vastly improve balance.
• In addition it can greatly improve the torsion (twisting) strength that can vastly increase ability and performance in such sports as throwing, tennis, badminton, squash and swimming.
• The difference between having the edge in your chosen sport will time and time again come down to your ability to maintain the most efficient functioning of your core muscles, hence it has been coined the powerhouse of the athlete.

Reference: Sports Injury Clinic.net (2012)

Available online: http://www.sportsinjuryclinic.net/rehabilitation-exercises/core-strengthening-stability/introduction-to-core-stability