Theo Bos (born 22 August 1983) is a Dutch former professional road and track cyclist. An Olympic silver medalist and five-time world champion, he is the brother of Olympic medalist in speed skating Jan Bos.
On 29 November 2021, he announced his retirement from professional cycling and took up the job of coach of the Chinese national track team.
Bos was born in Hierden, Netherlands. He has an older brother Jan Bos, who is a professional speed skater.
He went to high school in Harderwijk, where he got a havo diploma. Later he also got a vwo diploma.
In 2001, he was Junior World Champion track cycling at 1,000 m. The same year, at the age of 18, he started his professional cycling career as a senior.
He won the silver medal at the 2004 Summer Olympics in the sprint event.
He won an individual gold in the sprint at the 2004 UCI Track Cycling World Championships. The following year, he won the individual sprint and a silver medal in the team sprint at the 2005 UCI Track Cycling World Championships.
At the 2006 UCI Track Cycling World Championships, Bos won the keirin and completed a career triple, having been world champion in the sprint, kilo and keirin. He won the keirin after accelerating with two laps to go, winning by a wide margin and able to raise his hands and salute the crowd as he passed the finish line. His French rival, and bronze medal winner, Arnaud Tournant, said Bos' performance was "the best I've seen in a very long time."
On 16 December 2006, Bos broke the world 200m track record during qualification rounds for the sprint at a World Cup meeting in Moscow. Bos clocked 9.772 seconds (after a computer initially had given him an unlikely 9.086 seconds) and beat the 11-year record held by Canadian Curt Harnett. Bos declared the 200m the "ultimate record" for track cyclists. Five days later Bos was elected Dutch Sportsman of the year. Bos' record was beaten by Frenchman Kévin Sireau at the Moscow Grand Prix on 29 May 2009 with 9.65 seconds.
Starting August 2017, Bos started riding for . He is in a team with Matthijs Büchli and Roy van den Berg. In 2017 Bos won the Dutch Championships in the team sprint with Büchli and van den Berg. At the 2018 UCI Track Cycling World Championships in Apeldoorn he won a bronze medal in the individual 1 km time trial.
On 19 April 2009, Bos was in a controversial crash in the final 800m of the final stage of the Tour of Turkey. Bos caused the crash of the eventual winner Daryl Impey by grabbing Impey's left shoulder with his right hand. Impey crashed to the left, into the barrier, next to Bos. Bos admitted pushing Impey. Bos claimed the reason for pushing Impey was because Impey was moving in on him while he was already close to the fence. Bos was disqualified and fined. On 1 May 2009 the Union Cycliste Internationale (UCI) said "BosâÂÂs behavior undermined the image, reputation and interests of cycling". Bos was charged with an infringement and was brought before a UCI disciplinary hearing in which he was found guilty of violating UCI regulations. Bos was subsequently suspended from professional racing from 15 August through 14 September 2009.
In the off season before 2010 Bos signed with the , that included former Tour de France winner Carlos Sastre. He was touted as another addition to their sprint team. He raced in many smaller races, and some large ones including ParisâÂÂRoubaix and the Vuelta a España. When the Cervelo Test Team folded in late 2010, Bos returned to the team. His first triumph of 2011 came in the first stage of the Tour of Oman, beating Mark Cavendish in a sprint finish.
In 2012, he won the first and last stages of the Tour of Turkey. Both of these stages saw crashes in the finale, diminishing the number of sprinters Bos had to compete against. Bos took his first win at World Tour level at the Eneco Tour. On Stage 3 from Riemst to Genk, he edged John Degenkolb () on the finish line in a bunch sprint to take the victory.
Bos was originally selected as a member of the Belkin squad for the 2013 Vuelta a España, however he was withdrawn before the start of the race after tests revealed he had low cortisol levels. A team statement noted that this was "an indication of sub-optimal health conditions", and that whilst low cortisol levels were not a barrier to competing in UCI World Tour races the team's medical staff and Bos had agreed to send him home. Subsequently, Bos confirmed that his condition was due to an extreme reaction to asthma medication.
Bos rode for the Pro Continental team in 2015 and 2016. Bos said about Team MTN-Qhubeka "The team has a great culture, I want to win and we will work together to win, our success is the success of Africa."
Following the 2015 Abu Dhabi Tour, where he did not finish stage 2, he had no further results at any major road events.