A comparison of posture and muscle activity means and variation amongst young children, older children and young adults whilst working with computers

Children and young adults are the most frequent users of computers. Whilst guidelines for adults have been based on research, available guidelines for children have had to assume children and adults are similar due to limited research evidence derived specifically from children. This study aimed to compare the posture and muscle activity of children with young adults. Thirty six adults aged 18-25 years, 24 children aged 10-12 years and 18 children aged 5-6 years participated in a series of laboratory studies. Upper body postures were measured using a 3D motion analysis system. Muscle activity of bilateral cervical erector spinae and upper trapezius muscles was assessed. Mean and variation were examined, the latter using both amplitude range and Exposure Variation Analysis matrix standard deviation. Mean postures assumed by children tended to show more spinal flexion and spinal asymmetry than adults. However children also tended to show more variation in posture and muscle activity. These findings suggest that whilst there may be differences in how children and adults use computers, basic principles of encouraging appropriate postures and variation should apply for both children and adults.