The Download: fusion power's future, and robotic running

How it works: The researchers built a lightweight exosuit with steel cables powered by electrical motors attached to the runner's thighs. The motors pull the cables, mimicking the contraction of muscles. The exosuit helps people run faster by assisting their hip extension--the powerful motion that propels a runner forward. Big ambitions: Buoyed by their findings, the researchers want to see if their exosuit can help a runner to beat the men's world record for running 100 meters. They're working on a customized exosuit for Kyung-soo Oh, a former national elite runner in South Korea who had retired, in a bid to break Usain Bolt's record of 9.58 seconds.