Human standing stability was evaluated using a swash plate drop device in a disturbance application. Under different experimental conditions using the device, electromyogram (EMG) measurements showed that the left and right lower limb muscles were used differently. It also demonstrated that the dynamics also differed depending on the experimental conditions. In particular, the dynamics of standing stabilization in a tandem standing position and a normal standing position significantly differed, and the activities of related muscles were also significantly different; this indicates that standing stability may potentially depend on the subjects. These results indicate the need for the comprehensive consideration of the standing and disturbance conditions during the quantitative evaluation of human standing stability.

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