A seat 10 including a headrest 13, backrest 11, 12 and a base seat portion 14 which are capable of reconfiguration (i.e. angular 17 or directional 18 adjustments) without input from the user. Seat reconfiguration is automatic with constant and/or continual succession of adjustments over time suitable for modifying its proportions relative to a user's body and thereby providing therapeutic exercise to muscles of the user. Once a user has set a reference position, activation of the system will send a continual pre-programmed or dynamically generated sequence of movement instructions to servos operating silently. Movement may be imperceptible to the user and by around 5 degrees of inclination, 5-10 mm of movement, or less. Installed in a vehicle it may reduce fatigue and may improve alertness and concentration on long journeys. Electric motors may provide movement. The application may be to other seating scenarios such as wheelchairs, aircraft, construction equipment, office chairs or domestic sofas. The steering column C may also have automatic adjustment.
