Abstract: Gymnasium equipment has a vertically movable column on the upper end of which are a pair of arm retention tubes which will accept arms of various items of ancillary equipment to perform a range of gymnasium functions. A gymnast will cause the ancillary equipment, and therefore the retention tubes, to rock about in horizontal axis, and in doing so cause a piston to move in or out of an hydraulic cylinder, displacing oil from the cylinder through a valve at a rate which is adjustable. With simple and inexpensive ancillary equipment, the invention makes it possible to achieve many different gymnastic functions.

Abstract: An hydraulic device is used for an exercise machine, having a double-acting hydraulic pump, which can be moved in one direction for developing one set of muscles (for example, biceps), and in the other direction for developing another set of muscles (for example, triceps). The invention provides a valve having two portions, each with a pressure regulating valve and a non-return valve. Oil displaced by operation of the pump in a first direction passes through a first pressure regulating valve, and return oil through a second non-return valve, and this is reversed when the pump is operated in a second direction. If the pressure regulating valves permit flow rates which differ, they can be made appropriate for movement effected by the different sets of muscles.