The running leg that I designed has a fairly similar design to typical running prostheses that currently exist. I decided to use a J-shaped 3.5" wide by 1/2" thick carbon fiber blade; this is typically the optimal design to absorb energy through each step and exert it outwards to add spring to each step. This leg is specialized in, as named, running. It has a shoe sole-like tread on the bottom of the blade to provide traction to the user. The blade is bottom-mounted to a stainless steel rod that is connected to the knee joint. This allows for not only a strong connection, but also a fluid one. It allows for the user to have a great feel for the blade, something which often doesn't happen with typical socket connection running prostheses.