An apparatus for measuring work performed by a subject in a magnetic resonance imaging device is provided which includes an actuating bar, an elastomer band positioned inside the actuating bar, a tower and roller bearing, and a pivot base supporting the actuating bar, the elastomer band positioned inside the actuating bar, and the tower and roller bearing. A force-sensing instrument for use in a magnetic resonance imaging device is provided, which includes a strain gauge cemented to a surface of an actuating device that is operable in a magnetic resonance imaging device. A surface coil holder having four degrees of freedom is provided. The surface coil holder is capable of being attached to a scanner table of an exercise apparatus. The surface coil holder includes a coil cradled in the coil holder and secured by hook and loop strips.
