Tyler Hamilton (born March 1, 1971) is an American former professional road bicycle racer. He is the only American rider to win one of the five Monuments of cycling, taking Liège–Bastogne–Liège in 2003. Hamilton became a professional cyclist in 1995 with the US Postal Service cycling team. He was a teammate of Lance Armstrong during the 1999, 2000 and 2001 Tours de France, where Armstrong won the general classification. He was a key asset for Armstrong, being a very good climber as well as time-trialist. Hamilton appeared at the 2000 and 2004 Summer Olympics. In 2004, he won a gold medal at the individual time trial. The first doping test after his Olympic victory gave a positive result, but because the backup sample was frozen, no doping offence could be proven. After he failed further doping tests at the 2004 Vuelta a España, Hamilton was suspended for two years from the sport.

Hamilton came back after his suspension and became national road race champion in 2008. In 2009, Hamilton failed a doping test again, and was banned for eight years, which effectively caused him to retire. In July 2010, he was subpoenaed to appear before a grand jury for the use of performance-enhancing drugs in cycling. In May 2011, Hamilton admitted that he had used banned substances in competition, and returned his gold medal. In 2012, he co-authored a book The Secret Race: Inside the Hidden World of the Tour de France: Doping, Cover-ups, and Winning at All Costs, which details his doping practices and experience in the world of cycling. On August 10, 2012 the International Olympic Committee (IOC) stripped Hamilton of his 2004 gold medal.

Biography Hamilton was raised in Marblehead, Massachusetts, and attended Holderness School in Plymouth, New Hampshire, where he started cycling. After graduating in 1990, he attended the University of Colorado at Boulder as a ski racer but never finished the final semester of his BA degree course in economics. A back injury (two broken vertebrae while mountain bike training on ski jump) at the University of Colorado developmental ski team in September 1991 ended his skiing, and he switched to cycling.

He turned pro in 1995 for the Montgomery Bell Cycling team which later became the U.S. Postal Service cycling team and raced for them in the 1997, 1998, 1999, 2000 and 2001 Tour de France. Hamilton protected Lance Armstrong in the mountains, and was on Armstrong's first three Tour de France winning Postal squads and quickly grew to stardom. Hamilton acted as a scout in individual time trials, riding as hard as possible to provide time-split comparisons for Armstrong. During this time he won the 1999 Danmark Rundt and the 2000 Critérium du Dauphiné Libéré, winning stages 4 and 5.

In 2001, Hamilton left U.S. Postal for Team CSC. He was made a leader under manager Bjarne Riis. Hamilton fractured a shoulder in a crash in the 2002 Giro d'Italia but still managed to win stage 14 and finish second overall, under 2 minutes behind race winner Paolo Savoldelli. Later that year, he participated in the 2002 Tour de France, riding in support of Carlos Sastre and finished 15th overall. In 2003, Hamilton became the first American rider to win Liège–Bastogne–Liège, breaking away from a select group of riders around four kilometers from the line in wet conditions. He later won the Tour de Romandie that year, as he prepared to race the Tour de France. In the 2003 Tour de France he broke his collarbone on the first stage in a pile-up. Instead of withdrawing from the race, he stayed to finish the tour, and exceeded everyone's expectations when he was able to follow and attack Armstrong up Alpe d'Huez on stage 8. Later, he rode one of the Tour's most memorable feats, winning stage 16 with a 142 km solo breakaway, gaining two minutes over the field. For his stage win, Hamilton was awarded the Coeur de Lion prize (French for Heart of the Lion, the name of the cheese maker that sponsored the award), as the most daring racer of the stage. He finished the 2003 Tour de France 4th overall and returned home nationally recognized.

In 2004, Hamilton left Team CSC and joined the Phonak Hearing Systems. He assembled a team of good, well-known riders and prepared for racing in the upcoming Tour de France, winning the 2004 Tour of Romandie for the second year in a row. Furthermore, he placed 2nd in the 2004 Dauphine Libere, beating Armstrong up the Mont Ventoux time trial which promoted him to one of the Tour de France favorites. However, in the 2004 Tour de France he dropped out on stage 13, after back pain mostly due to a crash on stage 6.

In 2021 he married his long time girlfriend Kristina Hamilton and they had a baby boy together.

In 2019, Hamilton joined Black Swift Group, LLC, an investment advisor and money manager based in Boulder, Colorado.

Olympic gold and doping confession At the 2004 Summer Olympics in Athens, Hamilton won the gold medal in the men's individual time trial. That medal was placed in doubt on September 20, 2004, after he failed a test for blood doping (receiving blood transfusions to boost performance) at the Olympics. Two days after the announcement of his positive test at Athens, the IOC announced Hamilton would keep his medal because results could not be obtained from the second sample. The Athens lab had frozen the backup, which made it impossible to repeat the test.Hamilton faces Greek drug probe, BBC on Monday, 20 December 2004. The Russian Olympic Committee appealed to the International Court of Arbitration for Sport to give Hamilton's medal to Russian silver medalist Viatcheslav Ekimov. However, on June 27, 2006, the court rejected the request.CAS rejects Russian appeal to strip Tyler Hamilton of Olympic gold, USAToday.com on Tuesday, 27 June 2006.

In the Vuelta a España, he won the stage 9 time trial on September 11, 2004, but left the race six days later, citing stomach problems. As winner of the stage, he was subjected to a doping test. He was told by the Union Cycliste Internationale (UCI) on September 13, 2004 that his two samples from two days earlier showed a "foreign blood population".Hamilton fails dope tests, BBC on September 21, 2004. After supporting Hamilton, Phonak team managers withdrew their support after a second member of the team, Santiago Pérez, was found positive for the same offense at the 2004 Vuelta a España.Hamilton third Phonak member dismissed for doping, ESPN on Tuesday, November 30, 2004.

The positive sample at the Olympics, and the positive test at the Vuelta were not the only indications that Hamilton was manipulating his hematocrit level. In April 2004 his blood was found to have a high ratio of hemoglobin to reticulocytes (young red blood cells), indicative of EPO or blood doping. His score was 132.9; a clean athlete would score 90. The UCI suspends a rider if the score exceeds 133. This sample also showed someone else's blood was in his bloodstream. However, neither piece of evidence in isolation constituted a positive drug test (and the test for a mixed cell population had not yet been adopted), so no action was taken.

On April 18, 2005 Hamilton was sanctioned by the United States Anti-Doping Agency and received a two-year suspension,Hamilton given two-year doping ban, CNN on Tuesday, April 19, 2005. the maximum sentence for a first offense.

On May 18, 2005, he appealed to the Court of Arbitration for Sport but, after allowing Hamilton to gather evidence, the court dismissed his appeal.International Court for Arbitration in Sport, February 11, 2006 (See: Case Law). Hamilton claimed the UCI-sanctioned test was insufficiently validated (and may have returned a false positive result) and that some of the agencies involved had concealed documents that would support his case. He also maintained that, even if foreign cells were present, they were natural and not the result of a transfusion.

Hamilton was banned until September 22, 2006, two years from the date his "B" sample in the Vuelta a España was found positive.

In 2010, Hamilton was subpoenaed by a federal grand jury to testify in their doping investigation of Lance Armstrong. Hamilton admitted in his testimony that he took banned performance-enhancing drugs during his cycling career.

On May 20, 2011, he also made the confession in an email to friends and family after a taping of the TV news show 60 Minutes, during which he also implicated Lance Armstrong in the doping scandal. Hamilton then voluntarily surrendered the gold medal he won at the 2004 Summer Olympics to the United States Anti-Doping Agency, which said it would continue its joint investigative work with the IOC.Hamilton gives back Olympic time trial gold medal. Cyclingnews.com (2011-05-20). Retrieved on 2012-02-20.

On August 10, 2012, the IOC officially stripped Hamilton of his 2004 Olympic gold medal and ordered that it be returned to them.

Operación Puerto On June 18, 2006, the Madrid daily El País alleged that the Spanish civil guard investigation of doping in Spanish professional sport, "Operación Puerto", had found that Hamilton paid more than US$50,000 to Dr. Eufemiano Fuentes between 2002 and 2004 to plan and administer his use of performance-enhancing erythropoietin (EPO), growth hormone treatment, blood doping, and masking agents. Las transfusiones y los dólares de Tyler Hamilton, El País, Monday, June 26, 2006. El País charged that Hamilton's 2003 win of Liège–Bastogne–Liège came days after a "double" blood transfusion planned by Fuentes. The evidence presented by El País also implicated Hamilton's wife in facilitating Hamilton's doping. Fuentes was arrested with team director Manolo Saiz in May 2006 as part of the Operación Puerto investigation.

On June 26, 2006, Hamilton stated on his website: "I was very upset to read the accusations against me and to see my name associated with the Operación Puerto investigation in Spain. I have not been treated by Dr. Fuentes. I have not done what the article alleges. In addition, I have never been contacted by authorities in Spain regarding these allegations. Therefore, it is impossible to comment on a situation I have no knowledge of."

The Copenhagen daily, Politiken, published further charges stemming from Operación Puerto on August 19, 2006. CSC-stjerne på omfattende dopingprogram i 2003, Politiken, August 19, 2006. The article summarizes Hamilton's alleged doping program during 2003. It quotes Danish doping researcher Rasmus Damsgaard on the organization Hamilton's program would have required. It cites Bjarne Riis, Hamilton's directeur sportif in 2003, denying knowledge of Hamilton's doping. And the article states that the reporters attempted to contact Hamilton on numerous occasions but were unable to reach him. The article's allegations are based on the rider's doping and racing calendar obtained by the paper. The calendar was seized in Operación Puerto. The doping calendar indicates use of EPO, growth hormone, testosterone, blood doping, and insulin on 114 days over seven months during the 2003 season. The racing program correlates with Hamilton's races in 2003, according to Politiken. The calendar includes two blood transfusions during the Tour de France. “The first time before the three stages in the Alps and the second before the 12th stage – a 47 km individual time trial,” write the reporters. The article stated that such an ambitious program would have required assistance – “at least four or five people,” according to Damsgaard.

The next day, August 20, 2006, the Belgian Dutch language Het Laatste Nieuws newspaper published more details of Hamilton's doping diary. Among many allegations, the article claims he took EPO 30 times between December 2002 and February 2003 while riding for Team CSC. In 2003, claimed Het Laatste Nieuws, Hamilton used doping on 114 of his 200 racing days.Extensive doping alleged for Hamilton. Cyclingnews.com. Retrieved on 2012-02-20.