The invention relates to a controllable load apparatus for use in machines for
resistive exercise training of the human body. The apparatus comprises a pneumatic
cylinder (10) having a piston (12) acting on a fluid and a piston
rod (14), the piston/cylinder unit (10, 12) being operated on by
a person undergoing training. A pressure accumulator (20) is connected to,
and pressurizes the piston/cylinder unit (10, 12) at a predetermined pressure
during exercise via a pneumatic control circuit (42). Once a predetermined
pressure threshold is reached, a valve means operates to prevent further fluid
being available for charging the accumulator (20).