Anfisa Reztsova is one of the few athletes who was very successful in both cross-country skiing and biathlon. Reztsova started as a cross-country skier and won her first international tournament medal at the 1985 World Championships, a gold in the relay. She repeated her relay victory at the 1987 World Championships and 1988 Winter Olympics and won additional silvers in the 5 km and 20 km at the 1987 World Championships and the 20 km at the 1988 Winter Olympics. She also won silver at the 1986-87 World Cup. In 1989 Reztsova switched to biathlon and competed as a biathlete at the 1992 and 1994 Winter Olympics, where she won a gold in the relay in 1992 and 1994 and bronze in the 1992 7½ km event.
At the World Biathlon Championships, Reztsova was less successful, her only medal coming in the team event in 1992, but Reztsova won the Biathlon World Cup two years in a row, 1991-92 and 1992-93. After struggling a bit in the mid-1990s in biathlon, Reztsova switched back to cross-country skiing in 1998. She won her third relay title at the 1999 World Cross-Country Championships, was fourth in the pursuit, and retired from competition after the 1999 World Championships. Reztsova later admitted to the Russian ski magazine Ski Sport that she had used performance enhancing drugs, including blood doping, during the 1998-99 season.