Stand with bare (or at least stocking) feet about 10 inches apart or slightly less than shoulder width. Have the outside edge of the feet going straight ahead which will make the inner edge of the feet appear to be angling in slightly toward each other. Keep knees bent slightly. Bend over forward until fingertips lightly brush floor. Bend the knees as much as needed to get hands to the floor. Use hands only for contact--do not put any weight on them. Let the head drop as much as possible, that is, let the head hang. Try to keep weight over the balls of the feet. If the heels are slightly off the ground try pushing them down and simultaneously pushing the hips up by straigtening the knees. Do not straighten knees all the way or lock them. Remember to breath. Making sounds enhances the exercise. See if it is possible to curve the upper torso. If the torso is too straight, balance will force the butt back behind the feet, but as much as possible the hips should be over the feet. Allow any vibrations to occur in the legs
Variation: Have a helper push down on the hips as you push hips up toward the ceiling.
Rationale: The most basic component of armoring is a chronic shortening of the large extensor muscles involved in the startle reflex--the calves, the hamstrings, the back and posterior neck muscles. This exercise directly addresses that tightness.
Letting the head go is very difficult for some people. It represents loss of control and vulnerability. During the exercise, it is not possible to scan the surroundings for possible threats.
Also gravity and stress tend to compress the body from top to bottom, and combined with exercises that bend the other way, this exercise helps lengthen the body. Increase in length helps with flexibility because it is partly the bunched up state of the average body that is responsible for widespread inflexibility.
Source: Alexander Lowen. Basic bioenergetic exercise.