Usain Bolt push Bolt to do longer sprinting distances with the aim of making the 400 m event his primary event by 2007 or 2008. Bolt was less enthusiastic, and demanded that he feel comfortable in his sprinting. He suffered another hamstring injury in March 2006, forcing him to withdraw from the 2006 Commonwealth Games in Melbourne, and he did not return to track events until May. After his recovery, Bolt was given new training exercises to improve flexibility, and the plans to move him up to the 400 m event were put on hold. The 200 m remained Bolt's primary event
Usain Bolt was shocked at how quickly Bolt had improved over the 100 m distance. The Jamaican surprised even himself with the time, but coach Glen Mills remained confident that there was more to come. On 31 May 2008, Bolt set a new 100m world record at the Reebok Grand Prix in the Icahn Stadium in New York City. He ran 9.72s with a tail wind of 1.7 m/s. This race was Bolt's fifth senior 100 m. Gay again finished second and said of Bolt: "It looked like his knees were going past my face." Commentators noted that Bolt appeared to have