Gait training improves performance in healthy adults exposed to novel sensory discordant conditions

Recent evidence shows that the ability to adapt to a novel discordant sensorimotor environment can be increased through prior training. We aimed to determine whether gait adaptability could be increased and then retained using a training system comprised of a treadmill placed on a motion base facing a virtual visual scene that provided a variety of sensory challenges that served as training modalities. Ten healthy adults participated in three training sessions during which they walked on a treadmill at 1.1 m/s while receiving discordant support-surface and visual manipulations. Upon completion, participants were presented with a novel sensorimotor challenge designed to test for transfer of adaptive skills. During this test, stride frequency, reaction time, and heart rate data were collected as measures of postural stability, cognitive load, and anxiety, respectively. Compared to 10 untrained controls, trained participants showed enhanced overall performance on the Novel Test, which was administered 20 min after their final training session. Subjects in both groups had greater stride frequency, reaction time, and heart rate when exposed to the new sensory environment; however, these increases were less pronounced in the trained subjects than in the controls. The Novel Test was re-administered to both groups 1 week, 1 month, 3 months, and 6 months later. Trained subjects maintained their level of performance for 6 months. Untrained subjects continued to improve in these measures at each subsequent test session, suggesting that a lasting sensorimotor adaptability training effect can be achieved with very short, repeated exposures to discordant sensory conditions.