Older, fit men are the ideal candidates. You really have to put a lot of trust in an astronaut, and so your best bet is likely going to be a man in middle age or older. honestly. Younger men are impulsive. Women are unreliable for the most part.
@Kairos This video is region locked, presumably to the USA? sad face
This might be a different clip: TheVerge.com
And here is an article quoting Scott Kelly as he recants his experiences (he even wrote a book about it): TheAge.com.au