In fact, when the biomedical designer Van Phillips created a state-of-the-art prosthetic for amputee runners in 1984, he didn’t even bother equipping it with a heel. As a runner who lost his left leg below the knee in a water-skiing accident, Phillips understood that the heel was needed only for standing, not motion. Phillips’s C-shaped “Cheetah foot” mimics the performance of an organic leg so effectively, it allowed the South African double amputee Oscar Pistorius to compete with the world’s greatest sprinters.
