Astronaut Sunita Williams qualified for the 2007 Boston Marathon in 2006 when she ran a 3 hour, 29 minutes, 57 second marathon in Houston. Williams is on board the International Space Station (ISS) in orbit more than 200 miles above earth. With a return date set for summer, the NASA flight engineer did not want her qualifying performance to expire while executing Expedition 14.

On April 14, Williams will run the 111th Boston Marathon, becoming the first Boston Marathon qualifier to run the prestigious race in space. The Boston Athletic Association issued Williams bib number 14,000 to honor her current mission.

Williams has been training on a special treadmill since she arrived at the ISS in December. The system incorporates a harness of bungee cords that pull on her hips and shoulders, and is designed to reduce impact on the space station.

Williams has benefited from all her training by maintaining bone and muscle density, a serious issue in reduced gravity.

Fitness has never been an issue for this endurance athlete who recently set the record for women's space walking at more than 29 hours.

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