Alexander Karelin (born September 19, 1967 in Novosibirsk, Russia) was a dominant Greco-Roman wrestler for the Soviet Union and later, after its dissolution, for Russia. He won gold medals at the 1988, 1992, and 1996 Olympic Games. Nicknamed the "Russian Dan Gable", and commonly referred to in the media as "The Experiment", he went undefeated in international competition from 1987 until 2000, when he was upset by American Rulon Gardner in the gold-medal match at the Summer Olympics. Karelin went the last 10 years of his unbeaten streak without giving up a point.

He competed at the heaviest weight class of his day, 130 kg (286 lb). His conditioning and incredible physical stature for his weight, perhaps combined with his dominance of the sport, led to him being known as "The Experiment" by much of the rest of the world. The term connoted at least a little bit of jealousy from others that could not match his strength and skill, and because of that assuming it was only possible through some kind of science experiment. When asked why he thought he was called that, Karelin noted that others don't understand because "I train every day of my life as they have never trained a day in theirs." He could have been referring not only to sports media, but perhaps also to other wrestlers and athletes.

Karelin was famous for his body lift, the "Karelin Lift", where facing the opponent who was lying flat on the mat to keep from being thrown, Karelin was able to lift the opponent from around his waist and throw him all the way over the opponent's shoulders, scoring from 2 to 5 points depending on the height of the throw. Karelin's ability to make this throw against opponents weighing 130 kg, also in elite physical condition, was simply amazing to audiences and other participants in and observers of the sport.