It has been long believed that the primary function of the
rectus abdominus (pictured) is to produce spinal flexion. All you
have to do is have a look the insertion and origin to see the logic
in this but is it logical?
From a standing position (the way our bodies were designed) if you
were to flex forward how much recruitment is required from them
rectus abdominus? Not much gravity does most of the work.
I would like to challenge your thought process for a moment first
look at the primary function of the core (that is the abdominal
section of the core) is it to create movement or prevent
movement? Most text books would have you believe that it is to
create movement but the fact of the matter is that the function of
the core is to prevent movement occurring stabilizing the lumbar
spine.
Now getting back to the rectus abdominus I see the primary
function of the rectus abdominus being eccentric deceleration of
the trunk into extension, thus preventing the spine from going into
extension and causing potential injury to the lumbar spine.
If you look at the anatomy of the rectus abdominus (RA) you will
see the RA is crossed by three fibrous bands which are named the
tendinous inscriptions; these aid in the eccentric bracing or
breaking external when forces are applied.
We all know by now that you should train for function first
especially when it comes to the core; so how can you train this
function?
One way is with an exercise I developed called Eccentric Abdominal
Bracing
To perform this exercise you will need some strength bands
(available here). Start off easy until you get the movement down.
First begin with holding the band overhead with arms straight.
Drive forward from the hip, not allowing the spine to go into
flexion. The actual movement looks very similar to a Good-Morning
exercise. The hip must be driven back and knees slightly
bent.
As you reach the end hip flexion release, allowing the band to
explosively pull you back into extension. At the top of the
movement before the back goes into extension, brace the abdominals
breaking and preventing extension of the spine.
So now you have a better understanding of the rectus abdominus and
an alternative to traditional flexion exercises you have no excuse
eliminate these useless exercises and start applying function to
your training.
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