1. You spend more than 9 hours a day sitting
2. Your back is deep
3. The back of most chairs, car seats, airplane seats and armchairs are flat
4. When your back rests on the backrest, the buttocks rest first, leaving a large gap between the lower back and the backrest
5. Sooner or later, your back sinks into the backrest and your upper body moves forward.
6. The weight of your upper body is counterbalanced by your lower back muscles (for 9 hours...)
7. Result - tension, fatigue and pain - relentless physical suffering and mental fatigue