Marita Sandig rowed on the gold medal-winning East German eights at the 1980 Moskva Olympics. She won four World Championship gold medals, at eights in 1977-78, and in the coxless pairs with Silvia Fröhlich in 1982-83. Sandig also won two coxed fours silvers in 1979 and 1981. Sandig and Fröhlich also won the East German nationals in 1984.
Due to the Soviet-led boycott of the 1984 Los Angeles Olympics, Sandig could not participate. She married Uwe Gasch in 1983 but later divorced. By profession, she became a graduated sports teacher but worked as a distribution agent for electronic household tools after German re-unification.