Flexion and extension

Besides stabilizing the spine, two primary functions of the core muscles are to flex and extend the spine. These actions are probably the most common ways in which people train the abs – these can include crunches, sit-ups, back extensions, and anything else that involves flexion and extension. However, since the core muscles are mainly tasked with stabilizing the spine, resisting these motions can also be a great core workout! Exercises like bird dogs, dead bugs, and even compound movements can be great ways to train the core to better stabilize the spine.
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