Not sure if joke or not, how long do they stay in space at a time? Surely an astronaut is keen enough to not make that mistake twice, if even once.
Another astronaut talking about the phenomenon of rediscovering gravity after a while in space
[video=youtube;Nxz5JJoDJtk]http://www.youtube.com/watch?v=Nxz5JJoDJtk#t=72[/video]