The design mimics the motion of walking but without the stress on the joints caused by the feet striking the ground or running surface. The actual motion of today's elliptical is a cross between walking, running and cycling. Various designs have evolved starting with "rear driven" version. Later models included "front drive" and more recently "centered driven". Typical models provide both upper body and lower body training. Some are motorized, others require you to provide the energy.
Cross training machines are best suited for cardiovascular training rather than strength training. In other words, you train the heart while working the legs. Some manufacturers state that users will actually burn calories at a higher rate than on a treadmill. Other studies though, say the rate is about the same although the perceived exertion is somewhat less. Since the exercise requires standing on foot pads while using the machine it provides weight bearing benefits. Weight bearing exercises help the body to maintain sufficient bone density, helping to ward off osteoporosis.
If you live in an apartment, the elliptical trainer provides an additional advantage. Since the feet never leave the pads during training, there is less noise. You get an effective workout and your downstairs neighbors won't have to listen to the pounding caused by walking or running on a treadmill. Also, many newer models require less space.
Prices vary widely. Machines (intended for a commercial gym environment can cost 00.00 and more. These machines are made for heavier usage and generally have more sophisticated programing than needed by most homeowners. Home versions can start as low as 0.00 and make a good addition to any home gym.
