The spine is fully loaded whenever you are upright or even bent forward as long as you are not using aids to walk (cane, walker or shopping cart). Without the use of aids, the portion of the spine that is loaded changes with different positions. When fully upright, there is approximately 30% load on the facets and 70% on the discs in the lower back. If you bend forward, the load increases on the discs and decreases on the facets. Visa versa if you extend backwards.
Dizziness and headaches are not associated with the lower back. However, increased pain can be associated with these symptoms. Post-concussion syndrome is highly associated with dizziness and headaches.
Dr. Corenman