Little bit under the weather

On June 17 1998, athlete Ato Boldon produced the best performance recorded in the men's 100-metre sprint. Yet his time of 9.86 seconds did not break the world record.

According to Jonas Mureika, a physicist at the University of Toronto, the Trinidadian sprinter was robbed by a head wind of the vital fractions of a second that would officially have made him the fastest man alive at the time.

In a paper submitted to the Journal of Mathematical Physics, Mr Mureika has presented a simple "back-of-the-envelope" algebraic expression to roughly correct men's and women's 100-metre sprint times for wind and altitude effects.

"The formula is pretty straightforward and could potentially be used by coaches, meet directors and the media to compare one performance with another," he said.

With top sprinters separated by just a few hundredths of a second, the effects of both wind and altitude are significant.

A head wind increases the drag on a runner, slowing his pace, while a tail wind of two metres per second can shave a tenth of a second off a final time. Times also improve at higher altitude as the thinner air offers less resistance.

The International Amateur Athletic Federation does not take into account such considerations, though it does rule that a race run with a tail wind in excess of two metres per second is "wind assisted" and hence is ineligible for a record.

Mr Mureika's formula models the athlete's velocity as a function of time. All that is needed is the actual time, the altitude of the venue and the wind gauge reading to calculate a comparative value.