Pounding the pavement or soft trails—which running surface is better?

Conventional wisdom suggests that running on softer surfaces is better for the body than harder surfaces. However, in a recent New York Times article, the subject of running injuries on hard versus soft surfaces was examined. Exercise physiologist Hirofumi Tanaka of the University of Texas at Austin took a deeper look at soft-surface running and said he could not find any scientific evidence that a softer surface benefits runners. Tanaka developed an interest in the topic after experiencing a running injury. When he was recovering from a knee injury, an orthopedist told him to get off the roads and hit the trails. He took that advice and twisted his ankle and aggravated the injury while running on the softer, irregular surface.

In the aftermath of his accident, Dr. Tanaka said he could not find scientific evidence supporting that a softer surface is better for runners than a hard one, nor could other experts he queried. In fact, he suggested that it makes just as much sense to reason that runners are more likely to get injured on soft surfaces, which often are irregular, than on smooth, hard ones.