Here's all you need to know about The Incredible Hulk: When Bruce Banner, the Jekyll side of the title character, gets really angry ... his mass, like, triples.
Since when does anger trump conservation of mass? Yes, the Hulk is a comic book (become TV series, become animated series, become comic-book movie, become video game -- shuffle and repeat until brain is pureed). Can't a comic have a nodding familiarity with the real world? (Yes, it can. Batman, for example, makes the effort.)
So incredible, yes ... just not in a good way. Despite more than one million hits when I google
"science fiction" and "incredible hulk"
you can't make me call it SF.