Hips Take Walking in Stride, Ankles Put Best Foot Forward in Run

In a first-of-its-kind study comparing human walking and running motions -- and whether the hips, knees or ankles are the most important power sources for these motions -- researchers at North Carolina State University show that the hips generate more of the power when people walk, but the ankles generate more of the power when humans run. Knees provide approximately one-fifth or less of walking or running power.

A long history of previous studies has focused on the bio mechanics of human locomotion from a whole-body or individual limbs perspective. The study shows that, overall, hip generate more power when people walk. That is, until humans get to the point at which they're speed walking -- walking so fast that it feels more comfortable to run -- at 2 meters per second. Hips generate 44 percent of the power when people walk at a rate of 2 meters per second, with ankles contributing 39 percent of the power.