Elliptical trainers are the newest and most exciting machines on the market today. These machines offer a no-impact elliptical (or egg shaped) stride which can be done in either a forward or reverse motion. This elliptical motion will allow you to enjoy an excellent cardiovascular workout without the jarring of your hips, knees, ankles or lower back. The smooth motion of the elliptical movement works the large muscles in your lower body. By changing direction, incline and resistance, you will tone your gluteals and quadriceps better than with any other cardiovascular machine. It also effectively works the calves, hamstrings, and hip flexors. It's the perfect aerobic exercise to help increase bone density without the impact.