Belly-firming exercises target the rectus abdominus, which runs down the front of the stomach and flexes the abs. They also target the obliques, which are located on the sides of the stomach and rotate and bend your torso. Perform abdominal exercises at least twice a week, per the recommendations of the 2008 Physical Activity Guidelines for Americans. Rest a day in between sessions to ensure muscular rest and growth. Consult with your doctor before starting a new exercise program.
Bicycle Maneuver
The American Council on Exercise ranks the bicycle maneuver as the best way to firm and tone the rectus abdominus and obliques. Lie on your back and relax your shoulders. Tighten your abdominal muscles by pressing your lower back against the ground and imagining that you are balancing a grape in your belly button. Lift your feet off the ground, bend your legs and position your knees above your hips. Place your fingers behind your head, resting your elbows on the ground. Crunch your right elbow toward your left knee while straightening your right leg. Return to the starting position and do the same with your left elbow, right knee and left leg. Bend your extended leg if straightening it strains or arches your back. Complete 12 to 20 repetitions, stopping when you feel a burn in your abs.
Ball Crunch
ACE recommends ball crunches to firm and strengthen the belly. Sit on an appropriately-sized exercise ball. Your legs form a 90-degree angle on a correctly-sized ball. Get a larger ball if your hips sink below your knees or a smaller one if your hips are higher than your knees. Walk your feet forward, lowering your back onto the ball. Stop only your lower back -- the rest of your back and shoulders remain on the ball. Lift your hips into alignment with your knees, back and shoulders. Position your knees over your ankles and place your hands behind your head. Gaze at the ceiling and crunch your stomach forward 45 degrees. Complete 12 to 20 repetitions, stopping when you feel a burn in your stomach muscles.
Reverse Crunch
Reverse crunches firm the rectus abdominus and the obliques. Lie on your back, bend your legs and lift your knees over your hips. Rest your arms on the mat, tighten your stomach and gaze upward. Crunch your knees about 3 inches toward your shoulders without lifting your lower back or upper body off the ground. Stop when you feel tightness in your stomach and lower your knees to the starting position. Complete 12 to 15 repetitions, stopping when you feel a burn in your stomach.
Plank
The plank firms the tummy while toning the lower back and arms. Lie on your stomach, lift onto your elbows and position them under their corresponding shoulders. Rest your forearms on the ground directly in front of your elbows. Look at the floor, tighten your stomach muscles and lift onto your toes. Align your hip, shoulders, lower back, knees and heels. Hold this position for a duration that challenges your stomach without causing you to drop your hips to the ground or arch your back. Lower to your knees to ease exercise difficulty. Hold until you feel a burning in your abs, typically 20 to 60 seconds.
