Chrises previous post was excellent.


The lower abs are not only the hardest to traget, they also fatigue the quickest, so its advisable you begin by hitting them.

Ab training is simlar to most training.
In order to achieve the optimum level of gain you must use "shock therapy."
The cointinuous repetition of the same exercises will yield some gains, but greater results will be shown by keeping the body guessing.
Like weights its a good idea to switch your routine every 4 weeks or so.