In this video tutorial, viewers learn how to build great lower abdominal muscles. This exercise is done on the floor. Begin by lying down with your back on the floor. This exercise is called a lower leg curl with a heel press finish. Place the hands flat and palms facing the floor. Bring the feet up in a curl and extend the feet on the top of the rep. As your extend your legs, contract down on the muscles in your stomach. This video will benefit those viewers who are interested in health and fitness, and would like to learn an exercise that will help build the lower abs.