Katy Perry's Workout Guru Demonstrates 3 Intense Core Moves

Watch this short video of Katy Perry's workout guru detailing 3 hard-hitting core moves that tone & cinch the waist! He describes the plank, side plank, and a modified "downward-dog" move that looks intense! I already perform the plank and side plank on a regular basis, so now I'm off to give the down-dog move a try! Let me know if y'all try them, and what you think!