in the drawing to the side of the second longitudinal rail 22 so that the drive force of the drive motor 24 is conducted on a longitudinal center plane of the support apparatus 2 substantially symmetrically to lumbar support 8 upper body support 10 and head support 12 in a corresponding manner the drive force of the driving motor 24 is transmitted from the second support 22 to the first support 20 via a transmission mechanism not illustrated in the drawing so that the drive force of the drive motor 24 is conducted substantially symmetrically to the leg support 14 and the calf support 16 on a longitudinal center plane of the support apparatus 2 in a modification of this embodiment it is also possible to provide two drive motors for adjusting the supports 8 10 12 of which one is disposed on the first longitudinal rail 20 and the other is disposed on the second longitudinal rail 22 these drive motors being synchronously controlled in a corresponding manner it is also possible to provide two synchronously controlled drive motors for adjusting the leg support 14 and the calf support 16 one being disposed on the first longitudinal rail 20 and the other being disposed on the second longitudinal rail 22 as fig3 illustrates the drive motor 24 is located within a profile height of the first.