Balzer won gold in Tokyo in 1964 over 80 meters hurdles, eight years later at the Games in Munich she won bronze over 100 meters hurdles. In addition, Balzer, née Richert, won three gold medals outdoors (1966, 1969, 1971) and even five times in a row in the hall (1967 to 1971). In total, she set seven world records, being the first woman to cross the 100 meter hurdles under 13 seconds.
After her active career, Balzer worked as a trainer at SC Leipzig. Because she and her husband Karl-Heinz rebelled against the increasing practice in the GDR of distributing doping drugs to young people, she was forced to Dresden, where she worked as a sports teacher.
It was only from 1997 that Balzer worked again as a trainer. She led her son Falk to the top of the world over 110 meter hurdles and Anja Rücker in 1999 to the surprising World Cup silver over 400 meters.