In the comic book Iron Man, it’s Tony Stark’s bulky exosuit that gives him his superhuman strength. But in real life, those most in need of extra strength—those with cerebral palsy, for example, or the elderly—could never carry the weight of an enormous metal suit. Now Harvard researchers have developed a soft, lightweight exosuit, made of spandex with a robotic ankle that reduces the energy a user needs to exert by 23%. Researchers hope the exosuit will eventually help people with diseases like Parkinson’s or cerebral palsy walk more easily, as well as assist soldiers carrying heavy supplies in the field. Watch our video to see how the soft exosuit works.