Spartan workout plan

I saw 300 about a week ago. I need to get on the spartan workout plan. I wonder how the spartans had access to ab-rollers so early. I know that Sparta was probably a self-sufficient territory and the men probably did a great deal of backbreaking work, but come on. There was not one of them who was even a little overweight. Not even a pudge. I guess they were doing crunches between picking the fields and shoeing the horse. I can't imagine how they had time for cardio.