“To be weightless for the better part of a year, to never even have to lift my head
and then to have to be subjected again to my own inevitable weight having to
pick up my arm […..] It was an extremely unfair feeling”

Canadian astronaut Col Chris Hadfield speaking on the Today programme, (BBC Radio 4 29th October 2013),  about how it felt to return to Earth and experience the heaviness of his own body .

Most of us will never go into space and will never experience the weightlessness Chris Hadfield is talking about here. Floating and swimming in the water is probably the closest we can get. That is why they train astronauts underwater in special zero gravity tanks.