An easy choice for No. 1, the American swimmer debuted at the 2000 Sydney Games in the 200 fly as a 15-year-old, then amassed a record 14 gold medals over the next two Olympics, five more than anyone else in history. He won eight gold medals and set seven world records in Beijing in 2008.
Granted, he competed only in the Beijing Games, but the records Bolt set in the 100 meters (9.69, showboating at the end) and 200 meters (19.30) redefined our impressions of speed and the boundaries of the modern sprinter. (He lowered both marks at the 2009 world championships.) Bolt also won a third gold in China, anchoring Jamaica's 4x100 relay team to a world-record 37.10 seconds.
Following in a tradition of great Ethiopian distance runners, Bekele won four Olympic medals during the decade, winning silver in the 5,000 and gold in the 10,000 in Athens and then sweeping both races in Beijing four years later. In 1985, his fiancée, Alem Techale, died of a heart attack while on a training run with him and Bekele dedicated the races in China to her.
Lange drove three German bobsleds to gold medals during the decade: the two-man sled in 2006 and the four-man sled in both Salt Lake and Turin. At the Olympics and world championships, Lange has been on the podium at least once during all 10 years of the decade.
Ole Einar Bjørndalen
The greatest biathlete in history won four gold medals in Salt Lake City, in sprint, pursuit, individual and relay events. The Norwegian won two silvers and a bronze in Turin, extending his career total to nine Olympic medals, with more to come in February in Vancouver, where he will be 36.
After winning gold as a lightweight in taekwondo at the Sydney Games, Lopez returned to win gold and bronze at the next two Olympics as a welterweight. The American is the most decorated athlete in the history of the sport, having won gold medals in each odd-numbered year of the decade at the world championships, the only person to win five world taekwondo titles.
The Russian won six medals at the 2000 Olympics in Sydney, including two golds, to duplicate his haul four years earlier in Atlanta. In Sydney, he captured the all-around crown, certifying him as the most accomplished gymnast of his generation. He was also known for the sportsmanship he showed after receiving a low score for a sensational high-bar routine at the 2004 Athens Games. That controversy -- and not the celebrated Paul Hamm controversy -- led to an overhaul of the scoring system.
In his third and fourth Olympics, in Salt Lake City and Turin, the police officer/luger from Merano, Italy, won gold medals in men's singles to go with the bronze and silver he won in the 1990s. From 1994 through 2006, Zoggeler won a medal at the world championships or Olympics every year.
The Thorpedo was the swimming star of the Sydney Olympics, where he collected three gold medals and two silvers in front of a home crowd when he was only 17. Four years later he returned to win gold in the 200- and 400-meter freestyle events at the Athens Games, extending his medal total to nine, including five golds for the decade.
Ohno not only won five medals -- two golds, a silver and two bronzes -- at the last two Olympics, but he also popularized the sport of short-track speedskating. He skated with daring passes and sported a goatee that started a fashion craze among fans at short-track events.
After winning silver medals in both individual and synchronized 3-meter events in Sydney as a teenager, China's Guo swept the remaining four gold medals in springboard events for the rest of the decade. The woman known as The Princess of Diving stands as the finest diver of her generation.
Kerri Walsh/Misty May-Treanor
Perhaps the most dominant athletes in any sport over the decade, the American volleyball pair won gold medals in Athens and Beijing without losing a set. Their second Olympic triumph extended their unbeaten streak to 108 matches. (The streak, which spanned more than a year and included 19 titles, would end at 112.)
After winning five swimming medals in Athens, Coughlin captured six in Beijing, making her the first U.S. woman to win six medals at a single Olympics in any sport. She has won three gold medals, including two in the 100-meter backstroke, four silvers and four bronzes.
The only woman to win world-cup races in all five alpine disciplines also became the most decorated female alpine skier in Olympic history, capturing a total of four gold medals and two silvers at the 2002 and 2006 Games. Kostelic won the combined at both Olympics and also took the slalom and giant slalom events in Salt Lake City and silver medals for the Super-G in both years.
Coming off a string of world rowing titles in the last three years of the 1990s, Andrunache won five Olympic gold medals and one bronze during this decade. The Romanian claimed the coxless pair at all three Olympics, teaming with Doina Ignat in Sydney and Viorica Susanu in Athens and Beijing. She won her other medals in the eights.
The dynamic star of the piste captured gold medals for individual foil in Sydney, Athens and Beijing, becoming the first foilist and only female to win individual gold at three consecutive Olympics. She also captured a gold medal in the team event in 2000 and bronze in 2008. There was no team foil competition in Athens.
The long-track speedskater became the eighth winter Olympian to collect five medals at a single Olympics when she won one gold (1,500 meters), two silvers and two bronze medals in Turin. The performance made her the most decorated Canadian Olympian in history. She also won a bronze medal in the 3,000 in Salt Lake City. In between Games, she overcame a serious injury when another skater's blade sliced through her arm in training, cutting 12 of her tendons.
The German luger won gold medals in singles in both Salt Lake City and Turin. She began competing the following season during her pregnancy but decided to retire after a bad crash. She was feted before her home crowd in a lengthy retirement ceremony at the 2008 World Championships in Oberhof, Germany.
A mainstay on Canada's Olympic hockey juggernaut, Wickenheiser tallied 15 goals and nine assists in 10 games in Salt Lake and Turin, where her team won gold medals at both Games. Wickenheiser was also named to Canada's Olympic softball team at the 2000 Games in Sydney.
In Sydney, the older Williams sister won gold medals in both singles and doubles, the latter with her sister Serena. Venus returned with Serena to win the doubles event again at the Beijing Games in 2008. Both sisters have said they want to participate in the 2012 London Games.
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