The talk about air pollution at the Beijing Olympics last month apparently didn't bother Usain Bolt, the insanely fast Jamaican sprinter who broke his own world record in the hundred meters, 9.72 seconds, by running a cool 9.69. But scientists reviewing the tape now say that if Bolt hadn't let up early when it was clear he had the race in the bag, his time could've been 9.55. A research team led by Hans Eriksen at the University of Oslo studied footage of the race, concentrating on the positions of Bolt and the runner-up, Richard Thompson. Both runners slowed down at the end, and if Bolt had decelerated at the same rate that Thompson did, he would've finished at 9.61. However, Bolt slowed down even faster than Thompson as he pounded his chest in celebration. As a result, Eriksen says, Bolt's hot-dogging cost him even more time; if he'd run all-out across the finish line, he could have finished in as fast as 9.55. These times are not exact, but rather educated guesses, Eriksen says. The team didn't have the cameras recording 125 frames or more per second that it would need to do a more accurate measure of Bolt's motion. But they're confident in their findings, and are publishing them in the American Journal of Physics. In the NFL, the referees surely would've thrown a penalty flag for early celebration. In track, it just makes it more likely that someone—possibly Bolt himself—will soon blow away his new record. Anyway, Bolt isn't the first athlete hurt by premature celebration, and he probably won't be the last.