An apparatus for treating or training individuals while doing exercises permits a large range of motion while at the same time providing resistance. A hollow spherical housing having a spool and a cord inside is mounted within a support frame which permits the housing to rotate 360 degrees about a central z-axis and further about 120 degrees about the x-axis and the y-axis when the cord contacts the frame. A tension dial permits adjusting the tension applied to the spool to provide resistance as a user pulls the cord from the housing. When the user releases the force on the cord the cord is retracted onto the spool. The base of the support frame has opposing locking lugs which engage keyways in a co-operating socket which can be mounted on a variety of surfaces such as walls, doors and straps for attachment to a wrist or ankle or other body part.