Read More: "Chris Hadfield's next mission: Intensive rehab" "Months needed for bone and muscle density to recover from physical effects of space" "Human Physiology in Space Outline" "After 143 days in space, astronauts set to return" "Nearly five months of cramped living in zero gravity will come to an end Thursday for one American astronaut and two Russian cosmonauts aboard the International Space Station." "Your Body in Space: Use It or Lose It" "Besides eating and sleeping, what do astronauts spend more time doing in space than anything else? It's exercise." "Astronaut Fitness/Physical Conditioning" "How do astronauts maintain balance while in microgravity?" "Astronaut Strength Conditioning and Rehabilitation - ASCR" "The Astronaut Strength Conditioning and Rehabilitation Specialists or ASCRS provide a unique set of services to the astronaut community at Johnson Space Center. ks, the rigorous training schedule and the stress that space flight presents to the human body." "Intensive Rehab Next Mission For Astronaut Hadfield" "Chris Hadfield is back safely on Earth after five months on the International Space Station, but it will take several months for the Canadian astronaut's body to return to its pre-flight condition."