Abstract: In this preferred embodiment of a muscle building exercise device a disc is rotatably mounted in a frame in operative association with brake pads which resist its rotation. The brake pads consist of a pair of plates mounted in the frame, one on each side of the disc, which have surfaces containing friction material disposed in engagement with the face of the disc. The plates can be adjusted to tighten their engagement with the disc and thus increase the braking resistance to its rotation. The disc has rachet teeth in its periphery and is driven rotatably by a pair of lever arms which are pivotally mounted in the frame at one end and have a handle on the other. The lever arms carry a pawl which engages the rachet teeth and drives the disc when the lever arms are pivoted in one direction but passes over the rachet teeth when the lever arms are pivoted in the other direction.

Abstract: Disclosed is an exercising device in which stacked weights are manipulated by the user through a lever arm. A selected quantity of weights is raised and lowered on vertical guide rods by a lift rod. The lever arm is pivoted to the frame of the device and passes through a yoke in the upper end of the lift rod. A roller mounted in the yoke is carried on the upper surface of the lever arm. The lever arm is substantially horizontal when the device is at rest and as the lever arm is raised, the roller on the lift rod moves on the lever arm to reduce the user's mechanical advantage and increase his effective load. Also, as the lever arm is raised through its pivotal arc, a vectoring of the lifting force occurs, varying the portion of that force which is devoted to lifting of the weights, and thereby further increasing the effective load on the user. Further variations in resistance are possible by contouring the upper surface of the lever arm or the roller.