The Cyborg Leg It helps perfectly healthy runners run 30 percent more efficiently.
From Popular Science:
Attention cyborg wonks and lazy people: Japanese scientists at Tsukuba University have created a motorized knee that you can attach to your leg to increase your muscle power and running speed. The 11-pound kit's weight is shared by an exoskeleton-like attachment for your leg and a power source that's carried in a small backpack. But here's the best part: the device is not designed with any kind of rehabilitation or handicap-assisting function in mind; it's simply to make it easier for regular folks to run faster!
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