That's a particularly perplexing question for me since I have a very strong aversion to tight places. I can't work under cars without getting nauseated and if I ever have a medical condition that would require a full-body MRE, I'd almost as soon go ahead and die first.

If heroism is required on my part, running into a burning building or lifting a car off someone is more up my alley. At least thinking about doing either of them doesn't make me want to throw up.