Movement: Begin the exercise by lying on your back with a neutral spine. Keeping your eyes fixed on the ceiling, raise your head and shoulders off the floor several inches. Hold momentarily, lower and repeat. Note that your hands may be placed in front of the body to make the exercise easier or behind the body to make the exercise more challenging. Do not however, use your arms to pull yourself forward and cheat.
Caution: It's important not to raise your body too high or flex your back too far while performing crunches. This will place the spine in end range flexion, which can cause damage over time.
Instructions and effects for the Crunches exercise 
