Core training and Progressions with Donna Hutchinson
Core exercises are most effective when they engage many muscles throughout the torso that cross several joints and work together to coordinate stability. Core muscles need to work as a unit, contract at the same time, across joints in order to stabilize the spine. Some of the best core exercises are simple bodyweight exercises, including the following. The Basic Core Exercises are : a.Front plank b.Side plank c.Back plank
I put here a Quick Core workout