If there was an area of the body that we could train that could result in faster throws, hitting farther, throwing farther, running faster, would you use it?  Of course you would, it would only make sense.  The torso is the area that I’m referring to, and can help you maximize your performance on the field, court, or ice. 

The term torso refers to the middle area of the body.  Other terms that are commonly used to describe this region are core, abdominals, abs, or the trunk.  There are many muscles that are located in this region.  We will break the muscles down into two main categories, global muscles and local muscles. 

Local vs. Global Muscles

There are a number of muscles in the abdominal region.  They can be broken down into two primary categories, local and global muscles.  The local muscles are primarily segmental stabilizers.  The local muscles refer to the muscles that directly attach to the lumbar vertebrae. These muscles are considered to be responsible for segmental stability as well as controlling the positions of the lumbar segments.  The main muscles that make up this inner corset are the multifidus, internal oblique and transverse abdominus.  They are involved with segmental control and allow trunk movement in a controlled manner.  These muscles allow movement to be as efficient as possible.  They stabilize in quick and active motions, such as twisting and swinging.  Research shows that these muscles are initiated prior to limb movement in healthy individuals.  People who have chronic low back pain don’t activate these muscles prior to movement.  In other words their recruitment patterns are out of sync.  The reason that most people get back injuries is that they lose the ability to contract these muscles properly.  When this happens, the multifidus tends to atrophy (because of in-activation) much like the VMO of the knee does.  The internal oblique aids in torso stability as well as rotation.  The multifidus is a long strap like muscle that runs down the length of the spine.  Its primary function is that of a rotational stabilizer.  Those with chronic low back pain also demonstrate a motor control deficit in the TVA. 

The global muscles control orientation of the spine and form the outer corset.  The main muscles are the rectus abdominus, spinal erectors, external oblique, quadratus lumborum and lats.  Their primary function is to lessen the force that can be transferred to the inner corset during heavy loading. They also aid in rotational and side bending movements. These muscles help to produce and absorb force during large torque producing movements.  They have no direct attachment to the lumbar vertebrae.  The local and global abdominal muscles are independent of each other and should be trained separately.