The effect of different standing and sitting postures on trunk muscle activity in a pain-free population.

Study Design: A normative, single-group study was conducted.

Objective: To determine whether there is a difference in electromyographic activation of specific lumbopelvic muscles with the adoption of common postures in a pain-free population.

Summary Of Background Data: Clinical observations indicate that adopting passive postures such as sway standing and slump sitting can exacerbate pain in individuals with low back pain.