A truly exceptional athlete can make it all the way up to the Pro level. The S.A.A.A. does not currently divide the athletes into classes based on size or weight. The heavier athletes do have an advantage over the lighter athletes. Strength and skill are a big part of doing well at the games, but being able to throw your weight around doesn't hurt. The S.A.A.A. has established the following standards for moving up a class.
All distances are in feet.
I have heard the judges call a foul. All of the distance events are thrown from behind a trig. It is staked to the ground so it does not move. A box is drawn behind the trig. Some games use an imaginary box, but the S.A.A.A. paints the box directly on the grass.