Sure, we all covet abs that could grate cheese—but less so if getting them leaves your lower back in shreds, or your posture so crappy that no one can see the washboard beneath your hunched shoulders. And, if you really think about it, your spine is really only supported by those core muscles between your rib cage and your pelvis; bad training can set you up for all sorts of lumbar problems.

For abs that are both functional and brag-worthy, best to reconsider these six moves.