Backward, retro or reverse running has a few health benefits that regular forward running does not have, including increased balanced and the potential to burn more calories. Because backward running involves a reversal of running motion, it may work muscles differently, adding helpful variety to a runner's workout.
Additionally, backward running may give runners the opportunity to recover from common running injuries. The motion involved with backward running typically produces a softer impact than forward running, which may result in a safer run. However, the venue is important; running backward on a busy city street introduces a number of potential obstacles, from people to potholes.