Impossible to answer. The Mayan civilization had atheletes that competed for sacrfices to the gods. The pay seems to be horrible, but it fits the definition. Who's to say that other cultures didn't do the same? The Olympic games go back to the BC era, and some of them were supported so that they could train full time for the games. This too fits the definition.
Jim Torpe was the first duel sport athlete ...
Ilie Nastase, the first professional athlete to sign with BRS/Nike Wikipedia.org
Athlete who does it for a living.
That athlete is called a professional.
Jackie Robinson
Jerry Rice
jessica ennis is a profetional athlete
A Sportsman but it some people say it by the sport they do for example If someone played football you may call them a football player If someone was in the olypmics you may call them an athlete ect
Tim Lincecum
Yes
professional athlete
a lot