Hydraulic exercise equipment is a form of
exercise machine
An exercise machine is any machine used for physical exercise. These range from simple spring-like devices to computerized electromechanical devices to recirculating-stream swimming pools. Most exercise machines incorporate an ergometer. An ergome ...
used in a number of
strength training
Strength training or resistance training involves the performance of physical exercises that are designed to improve strength and endurance. It is often associated with the lifting of weights. It can also incorporate a variety of training te ...
programs. They are most often found in
circuit training
Circuit training is a form of body conditioning that involves endurance training, resistance training, high-intensity aerobics, and exercises performed in a circuit, similar to high-intensity interval training. It targets strength building and mu ...
gyms.
Hydraulic circuit training machines were first developed for The Henley Corporation in the 1970s, and are now becoming an increasingly popular form of exercise.
The fundamental principles behind these designs are based on
fluid dynamics
In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids— liquids and gases. It has several subdisciplines, including ''aerodynamics'' (the study of air and other gases in motion) an ...
: Force that is applied at one point is transmitted to another point using an incompressible fluid known as hydraulic oil.
For circuit training applications, each piece of equipment is specifically designed for a given exercise. The effort is applied through the range of motion of the exercise acts on a
lever
A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or ''fulcrum''. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is div ...
against a piston which moves linearly within a hydraulic cylinder. The cylinder is filled with hydraulic oil which is displaced by the motion of the piston, and is allowed to flow to the opposite side of the piston through an adjustable orifice.
Resistance to the motion is determined by the amount of effort applied and the adjustment size of the orifice. This is a key feature of this design and allows the resistance to be adjusted to an individual's strength level.
References
{{reflist
Exercise equipment