Spine Messages aims to reduce the potential harm of sedentary behaviour by making people aware of their bad sitting habits and prompting them to do corresponding stretching relief actions. The system monitors people's different sitting postures through a cushion with pressure sensors, visually conveying the resultant pressures on the sitter’s spine and recommending actions via a display screen. Through these concrete graphic and animated reminders, the system makes people realize the importance of regular stretching exercise in reducing the possibility of chronic spinal disease.