A plank is a really good test to put the entire ‘core’ under stress. The spine is part of the core but a properly done plank puts stress on the entire spine, shoulders and legs. It can be a good way to test to see how parts of the spine can function. ⁠

A plank is also a good way to work on the static strength of the core and spine.⁠Along with pushups, squats the plank is an no equipment required way of working lots of muscle groups in a ‘free’ way; no gym membership required. ⁠