Cam Machine: A variable-resistance machine with an elliptical wheel referred to as a cam, which is basically a pulley-wheel with an off-center axis.
The cam allows the cam machine to produce variable resistance by the use of a chain, cable, or belt that tracks over the high and low spots on the kidney shaped cam so that the distance between the cam's axle, which is the point of rotation, and the weight stack varies.
The supposed purpose is to allow the muscle to be equally worked through all ranges of motion.
Each cam for individual machines are designed for the specific exercise for which the machine is meant to be used.
Nautilus equipment, designed by Arthur Jones, are examples of cam machines that provide variable resistance.
The brand's name comes from the shape of the cam, which is shaped like a nautilus shell. Jones designed the equipment to eliminate the biomechanical disadvantages found in free-weight training.
Essentially, the idea is that when a muscle is at it's weakest range of motion, the cam delivers less load and when the muscle is at it's strongest on the 'strength cure' the cam provides more resistance. This type of changing resistance, based on the strength curve of the muscles, is also called "accommodating resistance."
Although Nautilus has become a generic term to describe all such machines, some other major brands are Hammer Strength (also started by Jones in his second go-round), Cybex, Body Masters, Icarian, and Galileo.
Variable resistance cam machine have some use in bodybuilding, but are of practically no utility in training for maximum strength.
This page created 07 May 2012 02:19
Last updated 21 Jul 2016 23:54