The shoes have a distinct look. They actually look more like sandals than shoes, or maybe some sort of unholy sandal-shoe hybrid. They aren’t designed for style, though. They’re called ForceShoes, because on the bottom of each sole are two force meters that record load data as the astronaut does his or her workout using the Advanced Resistive Exercise Device (ARED) equipment installed on the International Space Station.
So, why all the fuss? It’s important that astronauts get the prescribed amount of exercise to combat muscle and bone loss while weightless. It takes only a few days in orbit for the muscles to begin atrophying. That wouldn’t be a problem if you spent all your time in orbit, but if you ever want to come back to Earth, you need to keep your muscle mass high.
NASA chose the ForceShoe design because it offers comprehensive data about workouts. Astronauts could have just taken readings from force meters installed on the ARED machines, but having them attached to one’s feet allows for the collection of data along all three axes and can even track how weight is distributed.
Before the ForceShoes become part of the daily routine for NASA astronauts, they will be validated in a series of tests on the ISS. When NASA is satisfied it has the best solution available, the load data gathered by astronauts’ fancy new feet will be used to refine the exercise regiment.