An exercise apparatus comprising a frame, a pivot arm mounted on the frame, a resistance mechanism, preferably an elastomeric torsion member, and a positioning element which allows the pivot arm to be pivotally adjusted with respect to the frame, independent of the resistance element, so as to vary the...http://www.google.co.uk/patents/US5456644?utm_source=gb-gplus-sharePatent US5456644 - Multiple station exercise machine having relocatable torsion resistance mechanisms
