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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