Complex sentence: His first major victory was in the 1953 Mr. Universe contest and he actively competed until his retirement in 1971 after winning the Mr. Universe one last time, over Reg Park and Sergio Oliva.
Split into simpler sentences: His first major victory was in the 1953 Mr. Universe contest. He actively competed until his retirement in 1971 after winning the Mr. Universe one last time, over Reg Park and Sergio Oliva.