NASA via Associated Press, Joel Kowsky
Expedition 46 Commander Scott Kelly of NASA smiles upon arriving at Ellington Field, Thursday, March 3, 2016 in Houston, Texas, after his return to Earth. The Soyuz TMA-18M spacecraft landed near the town of Dzhezkazgan, Kazakhstan, on Wednesday with Kelly and Russian cosmonauts Mikhail Kornienko and Sergey Volkov of Roscosmos. Kelly and Kornienko are completing an International Space Station record year-long mission to collect valuable data on the effect of long duration weightlessness on the human body that will be used to formulate a human mission to Mars. Volkov is returning after six months on the station.

CAPE CANAVERAL, Fla. — Fresh from a year in space, NASA astronaut Scott Kelly says his muscles and joints ache. His skin is so sensitive it burns when he sits or walks. And he can't sink a basketball shot.

He's surprised. After his previous five-month space station mission, he wasn't nearly this tired or sore. And he lost the 1½ inches he gained in space, almost as soon as he stood on solid ground.

Kelly returned from the International Space Station on Wednesday, ending a 340-day mission that set a U.S. record. It took him a full day to get back home from Kazakhstan to Houston. That's when the aches and pains set in. He held his first post-flight news conference Friday, drawing a crowd at Johnson Space Center.