The invention is directed to an exercise apparatus for use in stretching. The method includes the steps of forming at least one non-critical feature on the mask utilizing one of a low-transmission phase-shift mask and a non-phase shifting mask, and forming at least one critical feature on the mask utilizing a high-transmission phase-shift mask. A membrane, disposed below the bed, contains a cruciate cutout into which are formed a major axis slit and a minor axis slit. If a user operation instructing to make the displayed image darker, in response to this user operation, a frame having an exposure condition of underexposure is selected and output from the moving image data to be reproduced from the recording portion for each period of a single frame of display output.