Show a Little Belly.2)Plank with Knee Touch.

Start in the push-up position. Extend your arms so your hands are directly beneath your shoulders. Your legs should be straight, with your weight on the balls of your feet. Keep your abs taut and your body in a straight line.

Pulling your abs in tightly, slowly touch your left knee to the floor. Return your left leg to the starting position, then repeat the move with your right knee. Repeat, alternating sides throughout the exercise.

Make it harder: Support your upper body on your forearms, with your elbows beneath your shoulders and your hands together. Your arms should form a triangle.

Denise Austin is the author of several books including Sculpt Your Body with Balls and Bands and the host of two Lifetime Television fitness programs.