Studies on seated posture show that spinal alignment depends on visual target height. When the screen is too low, the thoracic spine flexes to bring the eyes closer. This results in a rounded upper back and reduced lumbar support. The spine is no longer stacked efficiently, increasing muscular load. This inefficient posture leads to quicker fatigue and discomfort.
The longer the session, the more pronounced the collapse becomes.
Laptop users often sit on the edge of their chair to compensate for screen distance. This reduces contact with the backrest and removes lumbar support entirely. The pelvis tilts backward, flattening the lower spine. This posture stresses spinal discs and surrounding ligaments. Over long sessions, this increases the risk of chronic back pain. Many users do not realize this shift is happening while working.