With the variety of planks, you work your entire abdominal wall instead of the first layer. (turbulencetrainingforabs.com)
The separation of the abdominal muscle, which can be identified while pregnant or after birth, causes back pain and a weak abdominal wall. (bellefit.com)
An insane number of articles have been written about how to achieve a flat, tight abdominal wall. (blog.fitplanapp.com)