The crunch is the classic abdominal exercise—and it really works, but only if you do it correctly. Be sure to focus on your form throughout the full range of motion to get the most out of each crunch.
Lie on your back on the floor with your knees bent so that your feet are resting lightly on the floor and your knees are folded toward the ceiling. Keep your pelvis in a neutral position. Bend your elbows straight out to the side as you place your fingertips just behind your ears; this will help you balance and will stabilize your head. Do not put your hands behind your head and pull, as this may cause neck injury (see Photo 1).
- From the starting position, engage your abdominal muscles, squeezing downward just below your belly button. As you squeeze downward, be careful not to tilt your pelvis upward or dig your feet into the floor. This abdominal squeeze should bring your shoulders just slightly off the floor and generate a slight curve through your center (see Photo 2).
- Keeping your feet light on the floor, use that abdominal contraction to bring your upper body up toward your knees in a rolling motion, until your shoulders come fully off the floor. Keep your neck neutral, so that your chin stays off your chest—you should have room to fit your balled fist between your chin and your chest (see Photo 3).
- Hold for a moment at the top of your lift, and then lower back to the starting position. Throughout this entire motion, the pressure of your feet on the floor and the position of your pelvis should be absolutely constant. Repeat for a set of 25 repetitions.