With sports records being set or broken by even one-hundredth of a second, virtually anything can make a difference, particularly the wind.

When meteorologists say that the wind is blowing at a certain speed and along a certain direction, it is not its momentary or instantaneous value but its average over a duration of say 2, 3 or 10 minutes. This is because the wind is never really steady, all the more so when it is light. If one were to plot a graph of the wind speed against time, it will show alternating ups and downs, called gusts and lulls. On occasions, like when there is a thunderstorm, the gusts can be extremely strong.

On 2 June 2007, at the Reebok Grand Prix in New York’s Icahn Stadium, a gust of wind robbed US sprinter Tyson Gay of his world record. Gay had run his 100 m in 9.76 seconds, which was a 0.01 second faster than the world record of 9.77 seconds held jointly by Jamaica’s Asafa Powell and American Justin Gatlin. However, as per the rules, the wind should not have been more than 3.2 km per hour, but while Gay ran, it was measured at 3.5 km per hour. The wind had lent a gentle push to Gay and helped him win the race but not the title.