Effects of active and passive light-touch support on postural stability during tandem standing.

[Purpose] Light-touch support (consisting of a load <100 g) is useful for reducing postural sway while standing and walking. However, it is unclear which types of touch and somatosensory inputs are more effective for improving postural control. This study aimed to clarify the effects of active and passive light-touch support, with and without visual information, on postural stability during tandem standing. [Participants and Methods] Eleven young healthy adults maintained tandem standing for 30 s under six conditions. The independent variables were light-touch condition (no, active or passive) and visual condition (eyes open or closed). Postural sway, as measured using a force plate, was considered to indicate postural stability. [Results] There was significantly less postural sway with active light touch compared with passive and no touch. Passive light touch resulted in significantly less sway than no touch. In addition, there was less postural sway with active light compared to passive light touch, especially with the eyes closed. The light-touch support force did not differ between conditions. [Conclusion] Both active and passive light-touch improved postural stability in comparison to no-touch. Active light-touch support significantly improved postural stability. These results could be used to inform therapeutic interventions within clinical settings.