I only do abs because I like the ripped ab look. If you hit the Runner World website, they have video's of the 3 main exercises I do. Do these 4X week, eat healthy, and run 30-40 miles/week and you will have ripped abs. Looks good when your outside running with you shirt off.

Here's my list in the order I do them

1. Crunches (left, right and center)
2. 100 Bicycles
3. this thing: http://exercise.about.com/od/abs/ss/abexercises_4.htm[/URL" target="_blank">
4. 6 inches (with different leg movements)
5.Plank
http://exercise.about.com/od/abs/ss/abexercises_10.htm[/URL" target="_blank">

20 seconds regular, 20 seconds with my right arm up, then left arm, then right leg thn left leg, then right leg left arm, then right arm left leg, then regular.

It works for me.

The exercises that got me a 6 pack are-

Weighted leg raises-

Using a roman arm chair start with just your legs but build up to where you can do 10-15 reps with a 20 lb dumbell btw your feet.

Side bends on romam chair-
Again start off with just your body weight and work up to holding a 25 plate behind your head

Weighted crunches-
Using a pulley machine start off with llight weight and increse. Keep your back stright and isolate your upper abs with just a small pulling movement from your abs.

A few key points about abs
- If you want true ab muscles you need to train them just like any other muscle. 2-3 x per week with at least 1 recovery day. Always use a progression overload scheme but never do a weight that you can't get up at least 12 reps as this can be bad for your back. You should do a weight that tires you by rep 15 tops though. When that gets easy you add weight. This 200 crunches per day **** is a complete waste of time you will not build muscle or strength that way for your core.

- Ab muscles can not be completely isolated. All ab workouts hit the upper pretty well regardless. When doing ab workouts always do it in the order of lower, obliques than upper. If you do upper first when you get to the lower you will be tiring the uppers before the lower abs get their workout.

-Switch workouts every 4-6 weeks. You tend to adapt to a certain workout and platue. You might find you can no longer increaase.

I guess I took core as meaning just abs. As for everything else I like doing one leg squats, one leg deadlifts, back extensions, push ups and rows.

Key points on that
- I wouldn't worry about progression overload for these exercises you will gain too much muscle. 15-20 reps is good and will add decent strength for running.

-Always train the opposit muscle to avoid an imbalance. Think push pull. If you train the quad(push)you have to work the hamstring(pull). Do pushups for your chest(push) you need to do rows for your back(pull).

-For running keep try to keep you workouts running specific. One leg squats, one leg stiff dead lifts, dumbell arm swings etc.

http://This message has been edited by runawayjesse (edited Nov-28-2007).

I keep it simple:

3 sets of raised legged crunches - right, left, center
72 Bicycles. (36 r 36 l)

Five day a week, usally after a run because I remember to then.

on a swiss ball

crunches + oblique crunches 12 - 15 lb medicine ball
http://www.shapefit.com/abs-exercises-medicine-ball-exercise-ball.html[/URL" target="_blank">
http://www.sissel-online.com/exercise/o-crch_medicine_ball_exercise.php[/URL" target="_blank">

back raises

forward leans
http://www.jumpusa.com/swissexercises2.html[/URL" target="_blank">

Ab pull ins

http://www.sissel-online.com/exercise/prone_knee_pull_ins_on_exercise_ball.php[/URL" target="_blank">

push ups - one hand on the MB on hand on the floor - roll the ball between your hands between each push up or do 10 reps - switch hands 10 reps

http://www.shapefit.com/chest-exercises-medicine-ball-one-arm-pushups.html[/URL" target="_blank">

planks

I don`t do these every day - I do 3 or 4 of these exercises 3 or 4 times a week

FWIW, I do basically the same workout as trifecta listed, 2-3 days per week, usually immediately after a run. I also incorporate no weight leg exercises on a 2-4 day per week basis. Those I actually like doing. Single leg squats, split leg squats, toe raises. I don't want to bulk up my legs, but doing as many single leg and split leg squats as I can for a given set still works the muscle plenty good for my purposes

I've also done the above as a running circuit, doing 1-2 exercises at each 'fitness station' along the path I run, with maybe 3-5 minutes in between sets. I've found that a 10-15 minutes warmup jog helps me to do the exercises better. That is a real good workout, but doesn't give you the satisfaction of a continuous run.

I do 2 for abs:

First one is to lie flat & stretched out (either on a bench or mat but a bench is better because you can't rest your feet on the floor) with arms extended straight out behind the head, & holding a 55cm Swiss ball between my feet. Then you bring your arms & feet upwards simultaneously, grab with your hands the Swiss ball that your feet are bringing up, & then lower both your legs & arms back to the starting position, but with the ball now held in your hands behind your head. You keep on going, the next rep the ball ends up back between your feet, the one after that in your hands behind your head, etc. Seems to be a pretty good workout for both the upper & lower abs.

Second one is to lie with your legs raised & ankles crossed so your thighs are perpendicular to the rest of your body & your knees make another 90 degree angle. Then take a medicine ball (I use 8 or 10 lbs) & hold it in your hands extended behind your head. As you crunch up, bring your arms holding the ball up & place the ball between your knees, then let your shoulders & arms go back down to complete the crunch (the ball stays between your knees). On the next rep, you grab the ball from between your knees as your hands come forward at the top of the crunch, and you take the ball back down behind your head as you finish the crunch.

I usually alternate sets of ab work with pull-ups, which is the only thing I do for my back. So I'll do 10 pull-ups, then 20 reps of abs, then another set of pull-ups, 20 more abs, etc. This lets you give the back & arms a little rest while you're doing the abs & vice versa.

Another way to challenge yourself & make a game out of it is to set a goal of total number of pull-ups (say 50), and after each set, you do a certain amount of ab work. So the more reps you do in each set of pull-ups, the fewer sets of abs you have to do. (Doing 5 sets of 10 pull-ups means 5 sets of ab work, but if you can't complete 10 pull-ups in each set & have to do 6 or 7 sets of pull-ups to get to a total of 50, then you have to do that much more ab work.)