Already the top medal winner of all time, Phelps is looking to add to his tally in Rio. Phelps has won 18 gold, two silver, and two bronze medals.
Latynina participated in the Olympics from 1956-1964, winning nine gold, five silver, and four bronze medals. Her best Olympics came in 1956, when she won gold in the team, all-around, vault, and floor exercise.
Andrianov was in three Olympics from 1972-1980. He had an incredible showing in 1976, winning four gold, two silver, and one bronze medal. In all, he won seven gold, five silver, and three bronze medals.
The Soviet Union's dominance in gymnastics spanned both men and women in 1956-1964, with Shakhlin leading the way for the men. He won seven gold, four silver, and two bronze medals.
Mangiarotti's dominance in fencing spanned 24 years, from 1936-1960. Remarkably, he won gold in four different Olympics. He won six gold, five silver, and two bronze medals for his career.
Ono was in the Olympics from 1952-1964. During his time, he won five gold, four silver, and four bronze medals for Japan.
Nurmi was one of the best all-time long distance runners, participating in the Olympics from 1920-1928. He won nine gold and three silver medals. His best Olympics was 1924 in Paris, when he won five gold medals.
Fischer's Olympics career started in 1980, when she won a gold medal in the K-1 500m. It finished in 2004, with two medals. She won eight gold and four silver medals for her career.
Kato participated in three Olympics from 1968-1976. He was able to win eight gold, three silver, and one bronze medal.
Thompson retired from the Games with eight gold, three silver, and one bronze medal from 1992-2004. It's worth mentioning that only two of her medals were individual events, with the rest coming in relays.
Lochte is hoping to add to his medal total with three successful Olympics under his belt already. He's won five gold, three silver, and three bronze medals.
Torres won four gold, four silver, and four bronze medals during her Olympics career, including three medals in 2008 at age 41. Her Olympics career began in 1984, and four of her medals came in non-relays.
Nemov participated in three Olympics, but only won medals in 1996 and 2000. The gymnast won four gold, two silver, and six bronze medals for his career.
Coughlin has won three gold, four silver, and five bronze medals in her Olympics career from 2004-2012. Five of her medals have come in individual events, with the rest coming in relays.
Known as the best male swimmer in history until Michael Phelps' arrival, Spitz won an historic seven gold medals at the 1972 Munich Games. He also won four medals in 1968, including two gold, one silver, and one bronze.
Biondi won eight gold, two silver, and one bronze over his Olympics career from 1984-1992. His best Olympics was 1988 in Seoul, when he won five gold, one silver, and one bronze medal.
Caslavska's dominance spanned three Olympics, winning seven gold and four silver medals. Her best performance was in 1968, when she won four gold and two silver medals.
Chukarin didn't participate in the Olympics until age 30 in 1952. Despite his late start, he was dominant with seven gold, three silver, and one bronze medal over two Olympics.
One of the best sport shooters ever, Osburn won five gold, four silver, and two bronze medals while participating in three Olympics in 1912, 1920, and 1924.
Lewis is the most dominant track and field athlete ever, with nine gold medals and one silver. He won gold in the long jump in four consecutive Olympics from 1984-1996. He also won gold in the 100m twice.
Gerevich dominated fencing from 1932-1960, winning seven gold medals, one silver, and two bronze.
Over two Olympics, Nakayama won six gold, two silver, and two bronze medals. He participated in the 1968 and 1972 Olympics.
Scherbo took home six medals in the 1992 Olympics, the most ever by a gymnast in a single Olympics. He won four bronze medals in 1996.
Keleti (left) won five gold, three silver, and two bronze medals in 1952-1956. She won gold in the floor exercise in both Olympics.
Hall won five gold, three silver, and two bronze medals from 1996-2004. His most dominant was the 50m freestyle, winning two gold and one silver.
Astakhova won five gold, two silver, and three bronze medals from 1956-1964. She won gold twice in the uneven bars and won three consecutive team gold medals with the Soviets.
Dityatin won three gold, six silver, and one bronze medal in 1976 and 1980. Eight of his 10 medals came in the 1980 Moscow Olympics, including all three gold.