Lower Abdominal Exercises On A Ball

Performing lower abdominal exercises on a stability ball adds something to typical ab exercises -- instability. According to a 2000 study published in the journal "Physical Therapy," researchers from Spain found that exercisers who performed curlups on a stability ball, as opposed to the floor, increased strength in the abdominal muscles as well as the muscles surrounding the abs. You use your core muscles to balance on a ball, which helps you develop firmer, flatter abs.

Ball Crunch

Denise Austin, TV fitness instructor and author of "Sculpt Your Body With Balls and Bands," says that because ball exercises incorporate more muscles for the same movements, you burn more calories, helping to shrink your belly. Austin recommends the ball crunch to target your lower rectus abdominus, or lower abs. Position your lower back on the stability ball with your knees bent at a 90-degree angle and your feet on the floor. Cross your arms over your chest. Lie back on the ball so your upper back also touches the ball. Tuck in your tailbone and raise your hips toward the ceiling. Exhale, lift your upper body and pull in your navel while you contract your abs. Inhale and return to the starting position. Perform 12 repetitions.

The Waterfall

The waterfall strengthens and tones the small muscles in your lower abdomen and pelvic girdle, helping to flatten your lower tummy. Lie flat on your back with your knees bent at about a 60-degree angle. Plant your feet firmly on the floor, hip-width apart. Grasp the ball with two hands, holding it above your rib cage. Inhale, exhale, lift your head and curl up your upper body as you roll the ball up your thighs and over your knees down to your ankles. Roll back your upper body, reversing the direction of the ball. Roll the ball over your torso and return to the starting position on your back. Repeat the exercise six times in slow, controlled movements.

Stability Ball Prone Walkout

Your lower rectus abdominus forms the six-pack along the front of your abdomen, and the corset-like transverse abdominus lies underneath your rectus abdominus. The American Council on Exercise recommends the stability ball prone walkout to work both those muscle groups. Lie on your stomach on a stability ball with your arms extended down to the floor, elbows straight. Exhale, contract your abs and walk your torso forward, lifting your feet off the floor. Continue until your knees rest on the ball. Keep your back long and flat, your arms fully extended and your hands below your shoulders. Hold the position for a count of five, inhale and walk yourself back to the starting position. Complete six repetitions.

Lower Tummy Firmer

The lower tummy firmer exercise yields benefits for both your lower abdominal muscles and inner thighs. Lie flat on your back with your arms at your sides, palms facing downward. Grab the stability ball between your feet. Raise your legs until they extend directly up toward the ceiling. Exhale and curl your lower stomach toward your upper stomach, lifting your buttocks off the floor. Inhale and return to the starting position. Perform 12 repetitions.