Question: do you get tired quickly in space or is it the same like earth?

Claudie Haignere answered on 1 Feb 2016:

In a short duration mission, you are very busy with the scientific and operational program of the mission, but you want to get a maximum of free time to experiment the pleasures of microgravity and the magic glance through the window. For that you take time in your rest-sleeping time, but you must find the right balance with rest in order to keep fit for the demanding mission. Hopefully, I would say that adrenaline and excitation helps a lot. Physiologically speaking your basic metabolism is lower in space (not facing so much muscular constraints as on earth) so this may give you more margins.