When i was in grade school, i would always be one of the best in the class with the situp test that was timed. now that i am a lil older, i can't always get up the far when i am exercising
(i admit it, i got a lil lazy) But i do like to do crunches and they seem to be very effective. it does not hurt my lower back and i can concentrate on the the ab area. i know that i have to have the diet up to par, but for my preference, it is crunches.