The present invention relates to an ergometer which is particularly suitable for examining a test person or patient in a magnetic resonance apparatus. It comprises at least one drive means which is provided essentially movably and at least one pneumatic piston/cylinder array (7) . The drive means is provided at the piston (20) or the cylinder (21) and pneumatically applied pressure between the piston (20) and the cylinder (21) constitutes a resistance or force to be overcome by the test person or patient by operating the drive means. The resistance or the force necessary to set the drive means in motion, particularly during operation, can be controlled and/or regulated and the piston (20) and the cylinder (21) are sized such that an air cus...