Elliptical trainers are primarily driven via the legs, Elliptical Machines and most are combination designs having handle-levers attached to each pedal-link for the purpose of enabling a burden on the artillery to provide a secondary source of energetic power. The user grips the handles below assume height and pushes/pulls them while shuffling the feet back and forth within their elliptically shaped paths. Thus the oscillating handle motions are dependently coordinated with the constrained pedal motions. Poorly premeditated machines are too dependent on the user's leg power, producing excessive hold speeds as a determination of mechanical ratios that do not provide enough advantage to the handle-levers. Consequently such machines feel to the user like their equipment are openly going along for the ride, rather than sharing in the work. The more suitable models tender a congenial combination of affiliation and leg exercise in the correct ratios.
There are claims that the single business exercise of an elliptical trainer can literally be more efficient in burning calories. The logic is that by exercising more muscle groups simultaneously, a also intense workout can be achieved in less time. It is also suggested that the perceived scale of exertion is lower. However, other studies have shown that the degree in which calories are burned on an elliptical trainer is similar to that on a treadmill. Thomas Altena, a professor of nutritional and exercise physiologist of the University of Missouri-Columbia measured oxygen retention, lactic acid build-up, heart rate, and perceived percentage of exertion to compare treadmills and elliptical trainers. According to Altena, the "physiological responses associated with elliptical exercise were nearly identical to treadmill exercise" .