Crunches seem to be everyone's least favorite favorite. Yes, I said that twice. They love to hate them or the late to love them. Most of the time, the people crunching their hearts out aren't getting the results they are looking for.
Problem: Crunches only target one portion of the abdominal muscles. What most people are looking for are to tighten and pull the abs up.
The Fix: lying face up on a stability ball with feet firmly planted on the floor hip to shoulder width apart, carefully inch your back so the ball is just at the lower back from the middle. Cross arms so hands touch each shoulder. Hold the belly firm and attempt to press your nose to the ceiling (obviously you can't), by raising the upper body upward, then lower back down to the starting point.
Why does this work? Because you first pulled the belly button inward and upward, you force the abs to contract to lift the upper body toward the ceiling instead of toward the knees. The rectus abdominus (central muscle attached to the sternum and pubis) the external obliques on each side of it, and the transverse abdominus coordinate together for the movement. The stability ball aids in forcing core stability because the upper body is not resting back down to the floor. You also avoid pulling on your neck by accident.