With two gold medals Nikolay Kruglov was the best biathlete at the 1976 Olympics. He won his first World Championship in 1974, a relay gold, but at the 1975 World Championships he won a full set of medals, gold in 10 km, silver in 20 km and bronze in the relay. In 1976, besides his two Olympic golds, Kruglov also won a bronze in the 10 km at the World Championships, which he would improve to silver at the 1977 World Championships. His last two medals at the World Championships, a gold and bronze, came in the 1977 and 1979 relays. Domestically Kruglov won three Soviet titles, at 10 km in 1974 and in the relay in 1973 and 1975. After his sporting career Kruglov worked as a biathlon coach. His son Nikolay is also a biathlete, who won a silver at the 2006 Olympics in the relay and was World champion in the relay four times from 2005-08.