Rezková was born and raised in Prague, where she married Rudolf Hübner, a fellow Olympic high jumper. She first trained in ballet and rhythmic gymnastics before changing to the high jump. In 1968 she improved her personal best from 1.66 to 1.87 m, and became national and Olympic champion. In the high jump world ranking she was first in 1968 and 1969, sixth in 1970–71, and ninth in 1972–73. She retired after 1977 and later became a goldsmith and athletics coach.