In 1972, just 35 minutes after Polish athlete Ewa Gryziecka had set a record for the women's javelin throw, Fuchs threw the javelin more than 2.3 m (7 feet 6 inches) farther, a total of 65.06 m (213 feet 5 ¹/₂ inches), her first world record. She went on to set a total of six world records while winning two European championships (1974, 1978), along with two World Cup and four European Cup Final competitions. At the 1972 Olympic Games in Munich, Fuchs broke the Olympic record to win handily. She set one of her world records in the 1976 Olympic trials and went on to win another gold medal in the javelin throw in the Montreal Olympics that year. She set her final world record in 1980, at Split, Yugos. (now in Croatia), with a throw of 69.96 m (229 feet, 6 inches), but finished only eighth in the Olympics in Moscow that year.

Fuchs was active in the Communist Party of East Germany; she later became a member of the leftist Party of Democratic Socialism and held a seat in the German parliament.