Yup, you read that right. As you can see in the photo above, it shows Peake running on a specially designed treadmill while inside the International Space Station. Essentially Peake was running in place but thanks to the RunSocial iPad app, it helped recreate the crowd, the route, and the cheering that follows. Peake also managed to complete the 26.2 mile course in 3 hours and 35 minutes.
Like we said, this required a specially-designed treadmill that came with bungee cords to help strap him down. It also monitored his vitals which were sent back down to doctors on Earth. According to NASA, they found that astronauts tend to lose about 15% of muscle during a spaceflight and 1-2% of bone mass a month while in space.
This is why regular exercise is important, and we reckon that with the completion of this marathon, Peake got one heck of a workout.