Sit-ups alternative?

hanging leg raises

I've found that "crunches" would not hurt my back that much and combined with some "plank" It's given me a little 6-pack

Crunches
http://en.wikipedia.org/wiki/Crunch_(exercise)
(25 in a row at the end of my exercises routine)

Plank
http://exercise.about.com/od/abs/ss/abexercises_10.htm
(15 X 30-60 sec)

I don't even do sit-ups anymore since I've discovered these 2 exercises :blushing:

well, lets be specific, INCORRECT sit ups hurt the back. But very few people perform a correct sit up.
Crunches are less stressful on the back correct, other activities are reverse crunches, planks, side planks, hanging knee bends, bycycle crunches, medicine ball twists, exercise ball routines (there are tons, google exercise ball core and you'll find a million of them), Bosu ball pushups are also good.

There are so many, I can't list them all, those I mentioned are just off the top of my head.

Just remember, with both sit ups and crunches, your chin should be UP AND OUT. you should be able to read a sign on the ceiling the whole time, never find yourself at eye level with your knees, never tuck your chin. You keep your chin out and your abs contracted during the routine, and you're back shouldn't hurt (unless you already have some prior injury).

speaking of which, I'm off to the gym to do my legs and core (lots of core today, I skipped it yesterday so I could focus on my death workout, AKA Tabata protocol )