Everyone has a favorite exercise. Maybe it's the one where you feel strongest, the one you get the most out of, or for whatever reason the one you like most. My favorite? I'm so glad you asked, planks. The plank is a simple exercise yet one of the best for core conditioning, plus it supports proper posture and improves balance. The plank can be performed in many different variations, each engaging different sets of muscles for all-around toning and strengthening with easily adjustable intensity levels.