Most trainers love to suggest doing planks to work the core, and for some pretty good reasons. The classic core-stabilising move is so simple, yet so effective. Plus, unlike some other core exercises, the plank is generally considered to be really safe for most people with low-back pain. A plank doesn't just work your core, though. Planks really enhance your everyday life, especially if you are someone who has a desk job or sits for most of the day. ~ Berceste