The deep core muscles may be essential for protecting the spine from excessive loading.
According to a new study, peak anterior shear loading on the lumbar vertebrae increases dramatically when the deep core muscles are not engaged. Additionally, compressive loading also increases on the upper vertebrae. In 4 out of the 5 instances of deep core weakness, the superficial longissimus thoracis act as a primary compensator.
Conclusions
This study illustrates the importance of proper core training and shows how the muscles of the low back can often take over in the absence of core activation. Although most people focus their core training efforts towards large, superficial muscles such as the rectus abdominis, an optimal core training routine should prioritize training of the deeper, smaller core muscles.
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