Elliptical trainers also commonly know as crosstrainers have been on the market now for over a decade. They have become very popular as unlike treadmills they provide a low impact cardio vascular exercise. Your feet never leave the ground and so elliptical trainers are ideally suited for those who want a demanding cardio vascular workout without the impact that can affect damaged knees, ankles or hips. There are two basic types, those with rear mounted wheels and those with wheels mounted at the front. The latter are often associated with an "extended " motion akin to skiing, whilst the compact rear units like a
Kettler Mondeo have a more vertical motion. It is important to try one out before buying.