US Patent 7682154 Balance practicing machine

A balance practicing machine that provides effective balancing practice through the compound movement of an adjustable seat that comfortably accommodates various body types. The balance practicing machine is equipped with a saddle-shaped seat upon which a user sits, a drive unit that imparts a swinging motion to the seat, expandable and contractible elements on the surface of the seat, and a mechanism to expand and contract the expandable and contractible elements.