Training potential of visual feedback to improve dynamic postural stability

Abstract

BackgroundDeficits in single-limb dynamic postural stability are predictive for reinjuries of the lower extremities, which are very common in sports. The use of force plates has become increasingly common to measure dynamic postural stability. Visual feedback on force-plate based stability outcomes have been shown to improve performance during static tasks. A similar effect might occur in dynamic tasks. Since dynamic tasks are generally more specific for performance during sport, this could have important training implications. Research questionWhat is the effect of visual feedback on postural stability outcomes during a dynamic stability task? MethodsTwenty-four healthy participants participated in this study. During measurements, subjects were standing on one leg while mediolateral position-controlled platform perturbations were used to evoke and measure balance responses. All participants were tested under three conditions: with visual Time-to-Stability (TTS) feedback, with visual Center of Pressure speed (COPs) feedback and without visual feedback. TTS and COPs outcomes were calculated over a 5-second time window after each perturbation and were compared between conditions. ResultsVisual feedback resulted in significantly better stability outcomes during the dynamic stability task. TTS feedback resulted in a task-specific feedback learning effect, as it resulted in a gradual improvement of TTS scores (from 1.09 s to 0.68 s; −38%) in absence of a significant change in COPs. COPs feedback resulted in a non-specific attention effect, directly improving COPs (without feedback 5.26 cm/s with feedback 4.95 cm/s; −6%) and TTS scores (without feedback 1.47 s with feedback 0.99 s; −39%) in absence of an apparent further improvement over time. SignificanceThe ability to improve performance of dynamic stability tasks when visual feedback is added could have substantial impact for rehabilitation. Possibly, the use of visual feedback during stability training could improve the effectiveness of postural stability training.