athlete vs keep-fit buff

athlete

noun
  • An exceptionally physically fit person. 

  • A participant in a group of sporting activities which includes track and field, road running, cross country running and racewalking. 

  • A person who actively participates in physical sports, especially with great skill; a sportsperson. 

  • She's the first athlete in her sport to obtain a corporate sponsor. 

keep-fit buff

How often have the words athlete and keep-fit buff occurred in a corpus of books? (source: Google Ngram Viewer )