The public are tired of empty promises when it comes to turning flabby tummies into stronger, flatter, leaner abdominals. For those willing to put a little effort into their workout, a new study sponsored by the American Council on Exercise (ACE) "the workout watchdog" reveals the best and worst methods for getting definite results.

The study, led by Peter Francis, Ph.D., at the Biomechanics Lab at San Diego State University, compared 13 of the most common abdominal exercises, some involving equipment, and ranked them from most to least effective. Subjects in the study included 30 healthy women and men, ages 20-45, ranging from occasional to daily exercisers. They were put through a battery of exercises, including the traditional crunch, modified crunches, partial body-weight exercises and exercises using both home and gym exercise equipment. Muscle activity was monitored during each exercise using electromyography equipment.