When it comes to getting your cardio workout either at your local gym or in your home gym, an elliptical machine is usually a better choice than a treadmill. One big advantage of the of the elliptical is that it does not pound your knees nearly as much as the running action (or even walking) on a treadmill. On the minus side, and elliptical machine will usually be the more expensive alternative than a treadmill machine. This is because it is a more complex piece of machinery and than the treadmill. However, this is only a factor for people having a gym in their home. If you belong to a health club, the cost is the same regardless because you are just paying your monthly dues.