Cross training is an exercise regimen that utilizes several modes of cardiovascular training within a single session. By combining different modes of exercise (e.g. running, biking, stepping, elliptical striding), you prevent the same bones, muscle groups and joints from being stressed over and over. As a consequence, cross training reduces the likelihood of your being injured as a result of over-training. In addition, cross training has also been shown to have a positive effect on cardiovascular function and a person's long-term adherence to a training program.