Abstract: A pneumatic strength training device that utilizes a sealed vacuum cylinder with an air pressure powered piston. The vacuum is obtained by removing the air from said cylinder and sealing said cylinder. The cylinder is then attached to a lever style lifting bar through a series of pulleys. The resistance encountered by the lifter is varied by positioning the pulleys at different locations on the lifting bar.

Abstract: A pneumatic weight lift assist apparatus utilizes a cylinder with an air pressure powered piston. The air pressure power is provided by a vacuum pump driven by an electric motor. The piston is connected to a weight stack by a series of pulleys and a cable. The piston may also be connected directly to a handle to provide direct resistance to a weight lifter. The power output of the piston is controlled by a variable speed electronic switch connected to the pump motor.

Abstract: Airlift apparatus used in conjunction with a weight lifting machine that utilizes a stack of weighs. It assists the weight lifter when fatigue occurs. Its construction is of plastic, consisting of a cylinder and a piston. The piston is moved by differences in air pressure which is induced by a vacuum pump located at the bottom of the cylinder. A cable and a series of pulleys connect the weight stack to the piston. The system is activated by the lifter at any stage of the lift by a foot or hand operated switch. When not in use the Airlift does not adversely affect the normal operations of the weight lifting machine.