Yes. It should be all-American athlete.
The word "All-American" as a noun is a proper noun referring to a person, an athlete. So it is a concrete noun.
no
Yao Ming
Jesse Owens (the star American athlete) was not held in Germany and it was not during the Holocaust.
This answer may vary depending on what you define as "successful," but generally, Michael Jordan is usually considered the most famous American athlete of his time.
i think you mean athlete's foot... damp socks
Jim Thorpe
Yes, he was a sprinter.
jackie robinson!
The American Athlete - 1996 2010-04-03 was released on: USA: 3 April 2010
The American Athlete - 1996 2014-02-17 was released on: USA: 17 February 2014