Think running a marathon is a challenge? Spare a thought for British astronaut Tim Peake, who not only ran this weekend's 26.2 mile London Marathon, but he did the grueling feat strapped to a treadmill 250 miles above Earth.
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Peake, the first British ESA astronaut (and 7th British-born astronaut) to be launched into space, has been living on board the International Space Station since December and had been planning the marathon slog for some time.
"I'm quite glad that this is happening later on in the mission so I've had plenty of time to get used to the T2 treadmill," Peake told BBC News shortly before Sunday's event.
Located in the station's Tranquility node, the hi-tech T1 treadmill has many similarities to the contraption at your gym, barring one extreme upgrade. As the equipment is operated in microgravity, to simulate Earth gravity (keeping astronauts in contact with the machine while running), shoulder and waist-mounted elasticated harnesses ensure there is enough pressure make running possible.
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You may be thinking that Peake may have had an easier deal, what with the lack of gravity, compared with his London counterparts who had to deal with 26.2 miles of 1-G, but think again.
"One of the biggest challenges is the harness system. Obviously, my bodyweight has to be firmly attached to the treadmill by this harness, and that can rub on the shoulders and around the waist," he said.
The treadmill on the ISS isn't there purely for entertainment and the occasional marathon, however. An astronaut's daily routine includes spending around 2 hours per day, every day, working out. Lacking gravity, the human body deteriorates in many ways during long-duration spaceflight. To manage the damage caused by muscle atrophy and bone wastage, a rigorous training regimen is worked into the crew's routine.
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As a former officer in the British Army (and current Army Reservist), Peake is no stranger to putting in physical effort. But on this occasion, he really went above and beyond the call of duty: He completed the London Marathon in 3 hours and 35 minutes. In 1999, he ran the marathon (on terra firma) in 3 hours 18 minutes, so he wasn't far from his previous record. To avoid any medical or unforeseen health issues that could hinder his ISS mission, space station medical team advised him not to try to beat his previous best.
As an added bonus, Peake also broke a world record.
"His latest achievement is surely his greatest - running the fastest marathon in space, on the only day-off from his grueling schedule is fantastic accomplishment," said Guinness World Records' Head of Records Marco Frigatti. "Tim is a true inspiration and someone we can all look up to. Literally."
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The previous space marathon record was held by NASA astronaut Sunita Williams who ran the Boston Marathon on the ISS in 2007, completing the challenge in 4 hours and 24 minutes. According to SPACE.com, Williams completed the 26 miles on the station's original treadmill that has since been jettisoned.
Interestingly, while Peake was running for those 3 hours and 35 minutes, the space station, which orbits the Earth at a speed of approximately 17,100 miles per hour, covered a distance of over 60,000 miles. So although Peake completed the 26.2 miles on a space treadmill, the treadmill completed 60,000 miles! Now that's an extraordinary marathon.
Watch a sequence of Peake's record-breaking marathon: