Get Your Sexy Back

Practice Kegels.
That's right: The pelvic floor is part of your core musculature. Tighten up the muscles as if you're trying to stop a urine flow. Repeat 10 to 20 times.
Do isometrics.
While sitting at your desk or standing in line at Macy's, brace your abdominals as if your rambunctious 5-year old nephew is about to head-butt you in the stomach. Relax. Repeat 10 to 20 times.
Vary your abdominal routine.
Incorporate side crunches and rotational movements along with straight, traditional crunches to target all muscles.
Slow down.
Go for quality, not quantity, when performing ab exercises; do them slowly, in a controlled manner, pausing at the top.
Exhale.
Don't hold your breath when performing crunches; rather, exhale as you crunch to further tighten those muscles.
Sit up straight.
Slouching pooches out your stomach, so stand and sit straight: your ear, shoulder, hip and ankle should form a straight line when you stand.
Learn how to engage your core.
Lie on your back with knees bent and focus on drawing in your belly button. Keep the muscles engaged while exhaling and inhaling. Tighten your core before performing any exercise (not just abs).
Drink more water.
You need 11 to 13 cups of water a day, according to the National Institutes of Medicine. Water keeps your digestive tract in tip-top shape and helps prevent bloating.
Take commercial breaks.
While watching TV, use commercial breaks to sneak in a set of crunches.
Keep the whole picture in mind.
Eat clean, do cardio five days a week for 30 minutes or more ,and weight-train twice a week. Flat abs will happen.