Sergei Bubka is a Ukranian pole-vaulter who, in the late 80's and early 90's, dominated the men's pole vault in international competition. He won numerous gold medals for the Soviet Union in the '88 games (he didn't compete in 84 due to the USSR-led boycott of the LA games), and in his illustrious career set--and broke--numerous records in the pole vault.
It has often been said that he intentionally broke his (prior) record by the minimum distance each time, even though he was capable of surpassing himself by wider margins--this was done to maximize the number of times that he would obtain a "new world record".