Exercise bikes offer a great cardiovascular workout. Like cycling on the road, riding an exercise bike provides an excellent low impact alternative to running with the additional benefit of toning the muscles of the buttocks and lower body. There are two types of exercise bikes, upright and recumbent. Upright exercise bikes are much like outdoor bikes in terms of rider position. Recumbent exercise bikes offer the user a laid back seated position with the legs pedaling in a horizontal position. Both provide the same level of cardiovascular training and calorie burning. Each bike has advantages and disadvantages relative to the other. The only way to determine which one is right for you is to try several models out to make sure it is comfortable and works the muscle groups you want to work the most.