linking bar 74 coordinates the rotational motion of the upper portion 16 and the lower portion 14 with respect to each other the relative motion of the upper portion 16 and the lower portion 14 controlled by a five bar linkage is the key feature of the apparatus 10 providing unique exercise benefits and greatly enhancing the range of exercisers who may use the apparatus 10 the apparatus 10 is symmetrical from left to right as illustrated in fig5 the base 12 is fabricated from identical left and right side assemblies 21 interconnected by the bottom cross rail 26 as well as through the upper portion 16 and the lower portion 14 by way of their respective journals 34 30 the bottom cross rail 26 is fastened to each bottom rail 20 by bolts 27 each substantially triangularly shaped side assembly 21 comprises a bottom rail 20 a front rail 22 affixed to the front portion of the bottom rail 20 and extending upwardly therefrom and a rear rail 24 affixed to the rear portion of the bottom rail 20 and extending upwardly therefrom the rear rail 24 being curved frontwardly at its uppermost portion to join with the front rail 22 near the top thereof each side assembly 21.