Myth 1 - you get abs by doing ab exercises
This is the worst myth. For 95% of you, doing crunches, situps, or ab machines will NOT get you abs. You already HAVE abs, if you didn't your torso would be as limp as cooked spaghetti. The real problem is that your abs are hidden. To see a visible 6-pack you have to remove the fat that is covering your abs.
Doing ab exercises will NOT remove this fat, only eating less and doing more cardio gets rid of the fat. Let me say that again, to get 6-pack abs you need to eat less and do more cardio! Grab the roll of skin/fat at your waist and pinch, how thick is it? If its more than 1/2", that fat is the reason you don't have a visible 6-pack!
Now if you you skinfold measurement over your lower abs is less than 1/4" and you still have no 6-pack, count your blessings! Your problem is much easier to solve, for you, you need to make your ab muscles bigger thru ab exercises using heavy weight and low reps as with any muscle group that you want to make grow.
Myth 3 - you can do spot fat removal
Where did this stupid myth get started? I get dozens of emails each week from people asking for exercises to remove love handles or belly fat.
You CANT do spot fat removal! If you have love handles all you can do is keep reducing your bodyfat by eating less and doing more cardio till they disappear. Your body decides where the fat will come off and there's not a dang thing you can do about it. Just keep reducing the bodyfat till the love handles go away. I've seen people completely wasting their time doing 50 minutes of hanging leg raises thinking it would give them lower abs, they would be much better off doing 50 minutes of jogging.
source:http://www.scoobysworkshop.com/TruthAboutAbs.htm