Complex sentence: Aleksandra Timoshenko become the Bronze medal winner at the 1988 Olympics and the Champion at 1992 Olympics, and became the role model for the "über-waif" rhythmic gymnast look.
Split into simpler sentences: Aleksandra Timoshenko become the Bronze medal winner at the 1988 Olympics and the Champion at 1992 Olympics. She became the role model for the "über-waif" rhythmic gymnast look.