Tracy Anderson's Top Exercises for Flatter Abs and a Stronger Core: This seven-move series, created exclusively for Health readers by Tracy, is part of our 30-Day Core Challenge: Transform Your Butt, Back & Abs. It promises to do wonders for your waistline just in time for summer. #HEALTHxTA | Health.com
One thing you'll notice: All four of these exercises involve the plank. That's because when you get into this position, every single muscle in the core has no choice but to work. And when they all do, you're on your way to total tightening. Go through this series six times a week, pairing it with 30 minutes of cardio. You'll see a major difference in no time. | Health.com
Get a Flat Belly in 4 Weeks Inner thigh crunch lift Lie faceup with legs extended in a wide split, toes pointing up and hands resting lightly on back of head (A). Rotate right leg out, dropping toe to face outward, and raise leg (B). Using inner thigh, lower leg and return to start. Do 30 to 40 reps; repeat on other side.