Wind assistance

In track and field, wind assistance is the benefit that an athlete receives during a race or event as registered by a wind gauge. Wind is one of many forms of weather which can affect sport.

Due to a tailwind helping to enhance the speed of the athlete in events like certain sprint races (100 and 200 metres), 100/110 metres hurdles, the triple jump and the long jump, there is a limit to how much assisting wind the athlete may perform under if the performance is to establish a record. If a tail wind exceeds 2 metres per second (3.9 kn) the result cannot be registered as a record on any level. However, the results within that competition still are valid because all athletes in a race would get equal assistance, and in field events it is just the luck of the circumstance at the moment of the attempt. The wind assistance maximums are only in regard to the validation of a record.

The exceptions are the combined events like heptathlon and decathlon. Here, the total score may be accepted even though some of the results had a tail wind of more than 2.0 m/s. Here, in events where wind velocity is measured, the average velocity (based on the algebraic sum of the wind velocities, as measured for each individual event, divided by the number of such events) shall not exceed +2.0 m/s (Rule 260.18). Higher average velocity was previously allowed as long as no individual event would exceed +4.0 m/s but the IAAF removed this rule in 2010.

There have also been cases where the prevailing wind has aided point to point long distance races like the 2011 Boston Marathon, however the nature of point to point courses invalidate allowable records by design.

Obadele Thompson ran the 100 metres in 9.69 seconds in April 1996 in El Paso. The result would have been a new world record, had it not been for the tail wind of >5.0 m/s. This was then bettered by Tyson Gay in June 2008, Gay ran a time of 9.68 seconds with the help of a +4.1 m/s tailwind. That mark was surpassed when Usain Bolt set the current world record the following year, 9.58 with a legal +0.9 wind.

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