Samenvatting

Background Information: Slumped sitting has been associated with low back pain. Low back pain has shown to affect postural stability. In the lower back of a healthy person, little is known about the effects slump sitting has on motor control and sway.

Objective: To investigate if there are differences in the amount of sway and sway velocity after a period of slump sitting compared to a period of active sitting.

Research Question: Does short term slump sitting affect the amount of postural sway in a young, active adult?

Study Design: Randomized controlled crossover study.

Methods: 11 healthy, active subjects were asked to sit for 20 minutes in a slumped position on a backless chair and 20 minutes in an upright position on a gym ball. At the start and between the sitting positions, they were asked to walk for 20 minutes. Measurements were obtained via a force plate at baseline and after each sitting position. Subjects sat on a balance tool and directly on the force plate for 60 seconds each during data collection.

Results: No significant differences could be found. Small, though non-significant decreases of sway in medial-lateral direction, path travelled by the center of pressure and vector velocity were found on the balance board only between active sitting and baseline. On the mobile force plate, only slump sitting compared to baseline showed a non-significant decrease in sway in anterior-posterior direction.

Conclusion: The findings suggest a non-significant influence of both sitting postures on sway and sway velocity. This implies that physiotherapists should not teach one specific sitting position but rather frequent changing of posture.