According to a Pilates pro, the proper form for crunches doesn't involve crunching up with your hands behind your head because it can lead to neck pain. Photo: Getty Images/Matthew Leete Written by ...

Building a washboard stomach What is the quickest and most efficient way of doing crunches? Here is the proper crunch form: Lie on your back, with your knees bent and your legs in the air. Your knees ...

Brace your core. Squeeze your abs as you crunch your obliques and lift your shoulder blades and upper torso off the ground. Keep your legs in the side position, your knees bent, and your feet stacked.