Space 25 April 2016 Would you float off the treadmill? How to run a marathon in space Astronaut Tim Peake ran the London Marathon aboard the International Space Station. Here's how he did it. Getty NSSign UpGet the New Statesman's Morning Call email. Around 36,000 people ran a marathon through London’s streets yesterday. But a lone figure, floating 400km above their heads, was tracing their steps too. Major Tim Peake, a British astronaut working aboard the International Space Station, ran the race in a very respectable three hours, 35 minutes, and 21 seconds. The achievement is all the more impressive, though, when you consider that he both ran the race and trained in what’s known as “microgravity”, the near-zero gravity conditions aboard the station. What exactly does that mean? First, the obvious: you’d float off the treadmill. To keep him in running position, Peake used harnesses and bungee cords, which bring their own problems in the form of abrasions, sores, and what space agency medic Dr Jonathan Scott describes as the weight of a “heavy rucksack”. This video, from NASA astronaut Karen Nyberg, shows how running works aboard the space station: The tightness of the harness dictates how much of your body weight you’re running with. Peake went for around 70 per cent during the marathon. So it’s easier than running on earth? Nope. Microgravity also wastes away muscle, which is why astronauts aboard the station exercise every day as a matter of course. The space station, at 23°C, is also considerably warmer than London’s 8°C temperatures the Sunday of the race. To add insult to injury, perspiration sticks obstinately to your skin in microgravity. Peake drank from a water pouch velcroed to the ceiling to keep himself cool and hydrated during the run. Did he beat his Earth record? Again, no. Due to the conditions, he ran slightly slower than his 1999 record of three hours and 18 minutes. However, he has still claimed the Guinness World Record for a marathon run in space, beating Sunita Williams, the only astronaut ever to have run one in space before. She completed the Boston Marathon in four hours and 24 minutes in 2007. How did he train? Jonathan Scott, Peake’s medic, designed a training programme that was relatively low-impact so the astronaut wouldn’t over exert himself. Peake also wasn’t allowed to run vastly more than his onboard companions. Scott says Peake is volunteering in human physiology experiments during his time in space, so “it’s also important that his overall exercise volume is not significantly greater than that of the other participating astronauts”. How bad would an injury be? Peake's accomplishment, while it may seem like a bit of a gimmick, was also relatively risky. Patrick Jaekel is an exercise specialist who has worked with Peake for two years, and said before the event: “He absolutely must not injure himself. He cannot injure himself.” This is because in space, an injury could impair Peake’s ability to do exercise, and therefore result in muscle wastage. Without regular exercise, he might not be able to walk by the time he returns to Earth in June. Did he get bored? A treadmill marathon isn't nearly as interesting as a run across city streets, but Peake watched TV coverage of the race and watched the streets go by via a digital running app called RunSocial. And he could console himself with the fact that, thanks to the station's own movement, he would have covered 86,000km during his run. › To combat Islamic State, the world's leaders need to restore order to Libya Barbara Speed is comment editor at the i, and was technology and digital culture writer at the New Statesman, and a staff writer at CityMetric. Subscribe To stay on top of global affairs and enjoy even more international coverage subscribe for just £1 per month!