Abstract: A muscular rehabilitation apparatus for exercising human body appendages through multiple geometric positions of the appendage with respect to the body including a support position with a curved track adjustably mounted with respect to a base and supported by the base. The track defines an arcuate path which tracks the outer extremity of a human appendage as it pivots about a joint, such as for example the movement of a hand at the end of an outstretched arm as the arm pivots at the shoulder. Another example includes the pivotal movement of a leg about the hip wherein the curved track follows the movement of the foot. A carriage is mounted to move upon the track between the end portions of the track and forms a connection between the appendage extremity such as for example, the hand or the foot with the track.