Most modern seating will give you a bad back.
The chairs below are great examples of what you'll find at home, in restaurants and offices. All but one tilt backwards. This is a problem for the human body as it encourages the pelvis to rock backwards and therefore forces the whole spine, including the neck, to slump into a C-shape.
The straining position of reversing the normal curves of the S-shaped human spine force vertebrae to move into an alignment that the body cannot self-correct and over time creates a classic slumped posture with a rounded back and forward head carriage and rounded, sloping shoulders that is associated with many body problems.
You can hold your spine upright by contracting the muscles of your back and shoulders in these chairs but your muscles will fatigue causing your body to ache.
Why is the seat angle so important for my back?
Match the angle of your sacrum when standing to your sitting angle.
This all about the mechanics of your body...
To support and alleviate aching and building fatigue in your back, neck and shoulders whilst sitting you can do two things:
*This can be seen on X-Ray films when comparing a standing film of the spine to a sitting film. The sitting X-Ray will look more twisted and tilted than the standing film.
**Your breakdown side was determined during your second appointment using the 'sit test'. Ask me to demonstrate these sitting tips next time you see me.