Explained: Why wind matters in athletics and how it cost long jumper Aldrin the record

Wind velocity in athletics is measured in metres per second using a wind gauge or an anemometer. Events in which wind speed is recorded are the 100 metres, the 200 metres, the 110 metre hurdles, 100 metre hurdles, long jump and triple jump. Wind speed of up to 2 metres per second is deemed legal during these events. A mark set when the wind speed is over 2 metres per second is called wind-assisted like Aldrin’s and Yarraji’s. When Aldrin jumped 8.37 metres the wind speed was +4.1 m/s and when Yarraji sprinted over the hurdles it was +2.1 m/s.

What are the types of winds?

Headwind is denoted with a minus sign followed by the value (for example -3m/s) and a tailwind with a plus sign (example: +4.1 m/s). A headwind – running into it, though not helpful for athletes, is also calculated by the wind gauge but there is no limit on it. Tailwinds help athletes in the six events. Also the readings are rounded off. “Rounding off happens like this. If it is +1.51m/s it will be rounded off to +1.6m/s. But if it is +1.49ms it will become +1.5m/s,” CK Valson, competition director of the Asian Athletics Association, said.

In the sprints, hurdles and the horizontal jumps athletes move in one single direction and hence tailwind can propel them to jump further or run faster. Wind speed does not matter in the 400 metres, which is held on an oval track. “In the 400 metres an athlete will come across wind from all directions as they are running on an oval track. If a runner gets assistance at one point in the 400 metres, at another point the athlete will face wind resistance,” Valson said. For events from 400 metres and upwards, the wind speed is not a factor.

What about throws?

Wind speed is not considered as a factor in any of the throw events. “In the shot put wind speed has no impact as it is a shorter distance and it does not affect the hammer (throw),” Valson said. Both the shot put and the hammer are heavy and weigh 4 kilograms in women’s competition and 7.26 kg for men. The discus and the javelin are thrown at an angle and distances can be adversely affected by both strong tailwinds and headwinds unlike the track events or the jumps where a tailwind helps an athlete. However too many variables and wind speeds operating at a height, make them unviable to consider.

What about combined events like heptathlon and decathlon?

Decathlon for men comprises 10 events of which three – 100 metres, long jump and 110 metre hurdles are held using a wind gauge. The heptathlon is seven events for women of which the 100 metre hurdles, 200 metres and long jump need wind measurement. Wind speed is allowed upto +4m/s in an event but the average for the three events in decathlon and heptathlon should not be more than +2m/s. “In combined events they take the average. They add and divide. It should not exceed the 2 metres per second limit,” Valson said.

Where is the wind gauge placed?

In the 100m, 200m, and both the hurdles it is placed 50 metres away from the finish line, not more than 2 metres away from the track and at the height of 1.22 metres. In the long jump and triple jump it is placed 20 metres before the take-off line. In the 100m and the hurdles, the wind velocity is measured when the starter’s gun goes off. For 100 metres the wind gauge measures velocity for 10 seconds and for the hurdles for 13 seconds. In the 200 metres, the wind velocity is measured for 10 seconds once the first athlete enters the straight.

In the jumps, Valson said the measurements are taken for 5 seconds from the time an athlete reaches the 40-metre mark on the runway. If an athlete’s run-up is less than 40 metres, the wind gauge immediately starts measuring.

What level of assistance would Aldrin have possibly got because of wind speed?

It is difficult to give an accurate number but Valson, who was a member of World Athletics’ international panel of officials, said in the long jump it could make a difference of 10 to 15 centimetres. Aldrin won gold with 8.37 metres but as it was wind-assisted it wasn’t a national record. His second best jump was 8.26 metres, which equalled the previous national record. However, Murali Sreeshankar, the record holder, broke the mark with a legal (within permissible wind limits) 8.36 metres. Aldrin won the gold but Sreeshankar rewrote the national record and finished second.

Have wind gauges malfunctioned?

One of the most famous and controversial records has remained in the books till date though a malfunction in the wind gauge came to light later. Florence Griffith Joyner’s world record of 10.49 seconds in the women’s 100 metres, set during the Quarterfinal 1 of the 1988 US Olympic trials, had a wind speed of zero. However, an IAAF (now World Athletics) study in 1995 found that the wind gauge had malfunctioned. Based on analysis of wind speeds during heats and qualifiers (tailwinds of at least 2.7 m/s and as high as five metres per second were recorded), the study concluded that when Quarterfinal 1 was being held the wind speed was actually +5.0m/s and not zero. The IAAF didn’t strike Griffith Joyner’s time off and till date it remains unbroken.

The next best is Jamaica’s Elaine Thompson-Herah’s legal 10.54 seconds set last year.

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