It is caused by postural imbalances and too many hours chained to your computer. The Balancing Act Picture your ideal sitting posture. You are sitting upright, feet flat on the floor, your head aligned directly over your pelvis. Your neck is nice and straight, as though your spine extends up through your skull, pulling your body into perfect alignment. The weight of your skull is perfectly balanced, so that very little effort is needed to hold your head up.
Life is good.
Now put your engineering brain cells in gear, and imagine leaning forward a measly one inch. The average head weighs 15 pounds. Instead of being supported easily on top of your spine, you now have a 15-pound stress on your spinal and neck muscles. By leaning forward one inch, you also compress your chest and abdomen, inhibiting your breathing. Your internal organs are compressed, and this is not good for them.