Abdominal and trunk aesthetics (aka washboard abs) is a common discussion topic between exercise professionals and their clients.

Media (e.g. social, magazines and TV) can exacerbate and perpetuate this infatuation with a well-defined, and highly visible ‘6 pack’.

Just like clients have different goals regarding their 6-pack, exercise professionals have different exercises that they consider optimal for ‘hitting’ those abs. To further complicate the matter, exercise professionals will also use a variety of language and terms to describe the way a person should contract their core muscles to get the best outcome. Terms include: abdominals, abs, core, core stability, core function, core stability exercises, core training, core stability training, and so on.

The key reason why core stability training has become prominent in training and research is two-fold:

1. The critical link of the lumbar spine providing structural control between the trunk and the hips; and
2. Its role in prevention of low back pain and lower limb injury.

However, some exercise professionals (e.g. sport and exercise scientists) suggest that core stability should be referred to as motor control stability. The reasoning is that it allows exercise professionals to use the concept globally across all joints and regions rather than just the trunk and lumbar spine. It is also suggested that the value of motor control stability is in the way it acts to prevent motion rather than initiate it.

When viewing trunk stability, one should remember that the anatomy of the
structures around the trunk and ‘core’ are far more complex than just the abs.

• Passive stiffness of the lumbar spine is provided by the osseoligamentous structures.
• The thoracolumbar fascia acts like a proprioceptor giving feedback to lifting activities, as well as being a large attachment structure abdominis (TrA).
• The for transversus paraspinals are essentially thoracic muscles that act on the lumbar via a long tendon that attaches to the pelvis.
• The quadratus lumborum has no direct action on the lumbar spine, but is thought to be a major stabiliser of the spine.
• The TrA and obliques increase abdominal pressure by reducing the circumference of the waist.
• In isolation, the TrA will increase the lumbar curve when contracted by pulling the lumbar spine inward, increasing lordosis. When contracted jointly with the diaphragm and pelvic floor muscles, they provide increased spinal stability.
• Rectus abdominis is typically trained to cause trunk forward flexion, and the thinking that crunches and sit ups are the only way to get rock hard abs has led to an.over dominance of this muscle in all core work.
• In addition to these are the connecting muscles that attach to ribs and thoracic spine, as well as the muscles of the hip and thigh which all play a role in influencing trunk function.
• Finally, the muscles that are often forgotten when trunk strengthening are the diaphragm and the pelvic floor.
• Some might argue that true spine stability is achieved with ‘balanced stiffening from the entire musculature, including:
  • The rectus abdominis and the abdominal wall;
  • Quadratus lumborum;
  • Latissimus dorsi; and
  • The back extensors of longissimus, iliocostalis, and multifidus.