Slim and tone my abdomen after pregnancy

Hi, I would like to know how to tone your stomach after pregnancy? I had my last child 3 years ago and my stomach seems pretty flat when I stand up, but when I sit down I have a small buldge on my lower stomach and it bothers me. I've tried sit ups and...

notice that it only flattens my upper stomach. Any help or advice you can give me on what to do or may work? Thanks!

The crunch

• Lie on you back.
• Place your feet on the floor as close to your bottom as possible and place your knees together.
• Rest your hands across you chest and relax the neck.
• Slowly raise your shoulders off the floor by contracting only the abdominal muscles.
• Don't come up too high - your lower back should always remain on the floor.
• Hold that position for a count of 1 and breath out forcefully.
• Slowly relax the stomach muscles and allow your shoulders to return to the floor.
• Repeat 10 - 12 times, rest for 60 seconds then repeat.

Lying Leg Raises
Firstly ensure that your legs are slightly bent throughout this exercise.
• Lie on your back with your hands, palms down under your buttocks.
• Raise your legs about 12 inches off the floor and hold them there.
• Make sure the base of your spine is pressed against the floor (this will ensure that your back has the correct support).
• Now trying to use just your lower abs, tilt your pelvis and raise your legs a further 6 inches.
• Hold for a few seconds then return to your original position.
• Keep going with this exercise until you can feel it in your abs.