How much does your head weigh? When your head sits on top of your spine it weighs 10-12lbs. As you lower your head forward, it's weight increases. It no longer has the support of your spine beneath it. Where do you need to work in your back to keep your head from falling off?
I recently came across an article, What Constant Texting Does To Your Spine and love the images from New York Spine Surgery & Rehabilitation Medicine. Check out their study Assessment of Stresses in the
Cervical Spine Caused by Posture and Position of the Head. The study shares that. "People spend an average of two to four hours a day with their heads tilted over reading and texting on their smart phones and devices." This is a shocking number! Of course if we combine that with time spent bending over laptops and other desk work, this is extreme-- A good reminder to keep moving and not stay stuck in one compromised position.
From a Feldenkrais perspective, it is not what you do but how you do it and to have multiple ways of doing the same thing. The point is not to rigidly always have your head on top of your spine. Instead, become more aware of what it feels like when the weigh of your head feels supported be your spine and when it doesn't and let your nervous system decide which it likes best.