Some generally accepted guidelines for posture and furniture at computer workstations are, in reality, myths. If rigidly followed, these misconceptions can lead to uncomfortable and costly mistakes.
Reality: “Picture-perfect” posture can be extremely fatiguing, especially when held for long periods of time. When sitting, the full force of gravity is carried by the upper body and can lead to fatigue, muscle strain, or joint pain. Prolonged, static postures reduce blood flow and deprive muscles of necessary oxygen and nutrients. Dynamic postures increase blood flow and allow for muscles to have small rest breaks when you work. Change your position frequently, and alternate sitting and standing. For instance, find an elevated work surface where you can stand and do your paperwork from time to time.
Reality: If given a choice, four out of five workers prefer to sit slightly reclined. A reclined posture is less fatiguing and easier to maintain than sitting erect. Sitting slightly reclined also reduces pressure on the discs in your lower back. **However, there is a difference between being slightly reclined and slumping.
Make sure your furniture and chair are adequate for your needs and use good work habits.Change postures and take frequent short breaks throughout the day.
Reality: Ergonomics should really be considered a process rather than equipment. Adjustability, by itself, is neither necessary nor sufficient. It is possible to achieve a good ergonomic solution with minimal active adjustments. What matters most is how well the workplace can be configured to fit the worker and the work. Unless the total workplace adapts to the size differentials of employees, users must accommodate the shortcomings. That accommodation can lead to discomfort, pain, and injury.
Reality: Some of the earliest formal measures of body size, called anthropometrics, were conducted by the military. To standardize the process, everyone was required to sit in a right angle position (erect, with the major joints at 90°). The center point of the entire range of motion of the major joints of the body is where the greatest power is exerted. That point is generally around 90°; however, this is not perfect, nor is it correct posture. In fact, research shows this position exerts excessive pressure on the spine. A less stressful posture is the so-called neutral or the dead person’s float position. This is the position the relaxed body assumes in weightless conditions or in water where joint angles are about 120°. This position puts much less strain on the joints and spine.