Unlike other muscle groups, abs take more effort partly because there's no bone connected to it. I've mentioned in some other journals that in order to work the core, in addition to abdominals, there's a connection with obliques and lower back. They also have to be worked.

As Ayk11285 pointed out that cardio and diet is a huge factor. For cardio, I would recommend any type of activity that requires constant movement. For example I train in Muay Thai Kick boxing. In Muay Thai when you throw any punch wheather is be a hook, cross, overhand, or uppercut, you are using a twisting motion, which incorporates a lot strength from the core. Same with swing kicks. In addition to cruches, just try 3 5 rounds on the heavy bag for a 6 to 8 weeks as your cardio, you really will begin to see results.

Hope that helps and keep us up to date on your progress.

It not that hard to get abs people think it is the hardest thing to just get abs burn for me i have to run about 8 miles and burn about 1500 hundred calories and work out for three days and rest just abs and cardio it also depends on you r body wieght to