 After two days of tests, Brüggemann reported that Pistorius used about 25% less energy expenditure than non-disabled athletes once he achieved a given speed.The study also found that he showed major differences in sprint mechanics, with significantly different maximum vertical ground return forces, and that the positive work or returned energy was close to three times higher than that of a human ankle.The energy loss in the blade during stance phase when the foot was on the ground was measured as 9.3%, while that of normal ankle joint was measured at 42.4%, showing a difference of more than 30%.