Bird Study Clarifies Running Mechanics

The tendons in a runner’s legs work something like a pogo stick, storing energy when he takes a running stride on flat ground and then releasing it to give a spring off the ground, researchers say. Their experiment using turkeys on treadmills has helped solve a long-standing puzzle: How do the muscles and tendons in the leg work together to make running easier? The answer, says Thomas J. Roberts of Harvard University, is that tendons, flexing and releasing like springs, do much of the work. Although his study used turkeys as test subjects, Roberts noted, “We certainly expect that what we find the muscles doing in turkeys is also occurring in other running animals, including humans.”