Traditional crunches and sit ups can strain your neck and back, and waste precious energy at the beginning of the motion. Total Core starts you with your abs already engaged. So you're getting maximum results all through your abs and obliques. The progressive power coils assist you through the most difficult part of the move, the upward motion, which means you can do more sit ups and exercise for longer with less stress and strain to your neck and back. Total Core is your easy workout solution!