Usain Bolt
Usain Bolt holds the Olympic and world records for the 100 meters at 9.69 seconds, the 200 meters at 19.30 seconds and, along with his teammates, the 4x100 meters relay at 37.10 seconds, all set at the 2008 Summer Olympics.
Bolt became the first man to win 100 meters, 200 meters and 4*100 meters relay at a single Olympics since Carl Lewis in 1984, and the first man in history to set world records in all three at a single Olympics. His name and achievements in sprinting have earned him the media nickname "Lightning Bolt".
Bolt's record-setting runs caused commentators to speculate about his potential to become the most successful sprinter ever. Critics hailed his Olympic success as a new beginning for a sport that had long suffered from high-profile drug scandals.
However, his performances caused suspicion among some commentators, including Victor Conte, head of the controversial sports nutrition center BALCO, and the lack of an independent Caribbean anti-doping federation has also raised concerns. The sprinter denied accusations, saying he had been tested four times prior to the Olympics, and had each time tested negative for banned substances. He also welcomed anti-doping authorities to test him to prove that he was clean, stating, "We work hard and we perform well and we know we're clean".
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