I should've known this would provide some fun conversation!😂 I already answered someone else in a little more depth so I'm just gonna post this wonderful book on the subject.

Boxing is the only sport that likely bucks this trend.The reasons why are explained in "The Arc of Boxing" by Mike Silver (and the reasons are fascinating).Silver has lots of boxing experts and boxers giving oral info in the book. Worth a read if you like these sort of questions.