Effects of augmented visual feedback and stability level on standing balance performance using the Biodex Balance System

This study compared the effects of visual feedback and stability level on standing balance performance using the Biodex Balance System. The analysis was performed on a 2 x 2 factorial design for the purpose of testing the main effects of the type of feedback (augmented visual feedback or none) and balance condition (less stable--Biodex level 2 or more stable--Biodex level 7). Four randomly assigned groups performed nine 20-second dynamic balance trials at stability level 2 or at level 7, depending on group assignment. The dependent variable was the mean stability index calculated as an average of the nine 20-seconds trials. A significant feedback by stability level interaction was found (P = .04). At stability level 7, augmented visual feedback mean stability index scores were better when compared to no augmented visual feedback (P < .001). No significant differences were found at stability level 2. Our data indicate that when balancing on a Biodex Balance System, as the degree of difficulty increases the effect of concurrent augmented visual-feedback is reduced. Key words: balance, visual feedback, posture, augmented