Abstract: A conditioning and exercising device which is characterized in a preferred embodiment by a rewind housing containing a rotatable pulley provided with a pull cord, which rewind housing is connected to a torsion spring or spool housing. The rotatable pulley is connected to a rotatable top spool connected to a torsion spring wound on a rotatably mounted bottom spool, also connected to the torsion spring, both spools of which are located in the spool housing. Accordingly, extension of the pull cord and rotation of the rewind housing pulley against the tension in the torsion spring wound on the bottom spool as the torsion spring reverse-winds on the top spool, facilitates an increasing tension in the pull cord. In another embodiment the pull cord is wound directly on the rotatable top spool and is unwound against the tension in the torsion spring as the torsion spring reverse-winds from the bottom spool onto the top spool.