In the hopes of creating a toned, flat belly, most people do sit-ups, which work the rectus abdominis, the long muscle between the ribs and the pelvis. But to really sculpt your abs, you must engage your entire torso.
The three-dimensional moves in this routine zone in on your core by targeting your abs from every angle. They work the obliques on your sides, the transverse abdominis deep in your belly, and the muscles along your spine, in addition to the rectus abdominis. (Want to exercise more but don't have the time? Then try Fit in 10, the new workout program that only takes 10 minutes a day.)
Do 2 sets of 10 to 12 reps of each exercise, 5 days a week, for a trimmer torso.
Knee Circles
A. Lie on back with arms resting at sides. Raise feet into the air and bring knees over rib cage.
B. With abs contracted and belly pulled in toward spine, slowly lower knees to side, then circle knees away from you and around to the other side. (Have bad knee pain? Here are seven knee pain remedies.) Complete the circle by bringing knees back to start position. Begin with small circles and increase the size for more of a challenge.
Complete one set and repeat in the opposite direction.
MORE: 9 Proven Ways To Lose Stubborn Belly Fat
Don't...arch your back.
Side Chop
A. Hold a 3- to 5-pound medicine ball or dumbbell and stand with feet hip-width apart. Sit back into a half squat, contract left obliques, and twist torso to left, bringing ball to the outside of left leg. Knees should point forward and stay behind toes. (Here's another easy 10-minute ab routine.)
B. As you stand back up, contract right obliques and twist torso to right, sweeping ball up and across body to right. Follow ball with eyes until it's over right shoulder. Return to start. Switch sides and repeat for one rep. (Want to walk off your belly? Try this.)
MORE: The 8 Most Effective Weight Loss Exercises
Back Extension
Kneel with hands on floor directly beneath shoulders, and knees directly beneath hips. Contract abs and back muscles, and simultaneously lift and straighten left arm and right leg until they are in line with torso. Hold for 3 seconds and lower. Switch sides and repeat for one rep.