Abstract: An exercise device having a foot harness securable about a foot of a user; a thigh harness having a rigid plate member securable about a thigh of a user; and a tension adjusting mechanism connected between the foot harness and the thigh harness. The tension adjusting mechanism includes a tubular housing having an elongated passageway formed therethrough terminating in a first and second housing end; a spring plate, slidably disposed within the passageway, having a first and second plate side; a spring having a first and second spring end; a flexible, fixed length, tension member having a first and second tension member end; and a positioning member in connection with the spring plate for allowing the user to selectively position the spring plate in a desired position within the passageway.