Watch | Scott Kelly shares how it feels to be back on Earth

Scott Kelly returned from the International Space Station on Wednesday, ending a 340-day mission that set a U.S. record. The NASA astronaut says his muscles and joints ache and his skin is so sensitive that it burns when he sits or walks. And he can't sink a basketball shot. After his previous five-month space station mission, he wasn't nearly this tired or sore. He lost the 1½ inches he gained in space, almost as soon as he stood on solid ground.