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By Hamish Johnston
On 16 August Usain Bolt sprinted to gold in the 100 m dash at the Beijing Olympics, setting a new world record of 9.69 s.
But could he have gone faster? Many people think so because after the first 80 m of the race, when it was clear that he would win, the Jamaican appeared to stop trying and begun celebrating.
Now, four physicists in Norway have analysed video of the race and concluded that he could have covered the 100 m in as little as 9.55 s (plus or minus 0.04 s) if he had maintained his pre-celebration acceleration.
In a second calculation, the physicists argue that if Bolt had started to flag in the final 20 m — but still matched the acceleration of runner-up Richard Thompson — Bolt still would have finished in 9.61 s (plus or minus 0.04 s).
Cynics have suggested that Bolt held back so he would have a better chance at cracking the world record again, but the world’s fastest man remains silent on exactly why he appears to have stopped trying.
He held back to conserve energy to break the record in the 200m, a much older and more prestigious record. One could debate whether the amount of extra exertion in the last 20m of the 100m actually would have affected his performance in the 200m, but athletes and coaches certainly believe that it does. For example, sprinters run just fast enough in the heats to qualify for the next round. So Bolt ran just fast enough to win the race and set the record in the 100m, saving himself for the 200m.
The sad truth about why Bolt held back is that he was hot-dogging and rubbing it in. What a jerk.
he was not rubbing it in he was just trying to reach a goal that he wanted to
so don’t be calling him a jerk just because of that.