Running Vs. Elliptical Cycling

Elliptical machines reduce the impact forces you get with running, and that can reduce the risk of injury to endurance athletes. You might have seen elliptical bicycles that allow active adults to engage in an exercise similar to running, but with reduced impact. A study published in the Journal of Strength and Conditioning Research put them to the test using a dozen experienced runners.
 
Subjects engaged in 4 weeks of using the elliptical bike or running, then switched over for 4 weeks of the other form of exercise. Both protocols increased ventilatory threshold, the point where you start breathing heavier during exercise, and neither protocol was superior to the other. In conclusion, scientists suggest these devices can be used as an effective cross-training tool.