British Astronaut Tim Peake Is Running the London Marathon From Space

Prepare to be a little bit ashamed of your weekend plans.

This Sunday is the 36th annual London Marathon, and roughly 38,000 people are expected to spend the day making their way through the 26.2-mile course. But one runner won't be at the starting line with everyone else -- he’ll take his mark about 250 miles above the Earth.

British astronaut Tim Peake will be running the marathon from the International Space Station. How exactly will this work? He'll be hooked up to the space station's treadmill, the T2 Combined Operational Load Bearing External Resistance Treadmill (COLBERT -- yes, named after Stephen Colbert) with a harness and two bungee cords.

Even though he won't be on the ground, he'll use an app called RunSocial to track his progress and take in images of London's city streets as he runs.

"I don't think you can ever do enough training for a marathon," Peake said during a video press conference earlier this week. "But I'm sure there will be a few points where I'll be wishing I did a bit more." He is aiming to complete the race in three and a half to four hours.

This isn't the first time an astronaut has run a marathon from space. Back in 2007, NASA astronaut Sunita Williams ran the Boston Marathon in four hours, 23 minutes and 10 seconds.