>> August 03, 2011
When you watch track and field meet on TV you may notice about two things that frequently said by the commentators- the time or distance achieved and the wind reading. This is because no matter how fast you ran or jumped, your performance could not be valued as "legal" when the wind reading is not within the legal limit. The use of wind reading only apply to these events- 100m, 200m, 110mh, 100mh, Long Jump and Triple Jump. One of the great setbacks in Southeast Asia is lack of concern among the track organizers about the use of wind gauge or wind reading. Before I go any further, let me tell you a fact that "to control the wind gauge is the easiest work in athletics meet".
Wind reading is usually expressed in meters per second (m/s). A positive reading (tailwind) means the wind helps the athletes or blowing from behind, while a negative reading (headwind) refer to the a wind blowing against an athlete as he or she move forward. In the affected events, all the "negative wind" such as -0.5, -1.8, -3.0 are considered "legal", while "positive wind" would be considered legal as as long as it's not exceeded +2.0, means +2.01 would be illegal and relevant results may not be ratified for record purposes.
What are their significance in the relation of athletes' performances? (A must read)
Scientific research indicated that advantage (and disadvantage) of every 0.2m/s of wind is about 0.01 second. It means a 0.5m/s of tailwind would help athletes to run faster by approximately 0.025s, whereas a headwind -0.5m/s would cost the athletes' time by 0.025 (same amount with tailwinds).
+1.0wind = 0.05s
+1.5wind = 0.075s
+2.0wind = 0.10s
+3.0wind = 0.15s
+4.0wind = 0.20s.
-0.5wind = 0.025s disadvantage
-2.0wind = 0.10s ...
In women's 100m, more advantage and disadvantage were found in the same amount of wind. Perhaps, bodyweight aspects contribute to the finding.
--> Tailwind: +1.0 = 0.07s ,+2.0 = 0.12s.
--> Headwind: -1.0 = 0.07s, -2.0 = 0.12s.
Case study; Christophe Lemaitre ran 9.92s (+2.0) at 100m in French Nationals recently, and his best time prior to the race was 9.95s (+1.0). It's a huge improvement when you take into account that he is expected to peak during the World champs (in less than 30 days) not during French nationals. But the question is, did he improve? the answer is 'officially YES'. However when you take all things into consideration he DIDN'T. Because 9.92s with +2.0 equates to about 10.02s. His previous PB (9.95, +1.0) would be around 10.00s, still faster by 0.02s when compared to his performance in French Nationals. Other examples;
Obadeli Thompson 9.69A (+5.7) in 1998. PB at the time 9.87A (-0.2).
---> Exact time: 9.90s (slower than his PB). #Both achieved at altitude which should include different calculation, but I will discus about "advantage in performances at altitude" in the next time.
Norjannah Hafiszah (MAS) 11.60s (-1.5) in 2011. Will she break the NR 11.50s held by G.Shanti?
---> Possible time: 0.0 (no wind) = 11.53s, +1.0wind = 11.48s (yikes... NR!!).
Click here to adjust / calculate / estimate your real time for 100m.
|Electronic Wind Gauge|
In 200m sprint, calculation involve wind reading, the lane, and altitude if relevant.
--> Tailwind: +0.5wind = 0.04s advantage,
+1.0wind = 0.07s,
+1.5wind = 0.11s,
+2.0wind = 0.15s.
--> Headwind: -0.5wind = 0.03s advantage,
-1.0wind = 0.06s,
-1.5wind = 0.11s,
-2.0wind = 0.15s.
Above information NOT include altitude and lane effects. Perhaps I'll need to discus about the altitude and centrifugal effect (lane effect) in the next post.
Case study: Leroy Burrell of USA ran 19.61s +4.0 at Texas in 1996. This performance was better than the WR at the time, 19.72s by Pietro Mannea. But it was not ratified because too much wind. However, after adjusted to 0.0 (zero) wind, his time was down to 19.83s.
Click here to adjust / calculate / estimate your real time at 200m in which you could include all factors (wind, lane, altitude).
110mh / 100mh
In the high hurdles, predicted influence of winds is much more higher than the other events. One of studies in the past mentioned that the time in 110mh improved 0.19s when assisted by wind +2.0m/s. Below is the detailed information for men's 110mh / women's 100mh (from other studies);
--> Tailwind: +1.0wind = 0.12s / 0.11s advantages
--> Tailwind: +2.0wind = 0.22s / 0.21s advantages
--> Headwind: -1.0wind = 0.13s / 0.13s disadvantage
--> Headwind: -2.0wind = 0.27s / 0.28s disadvantage
Case study: Rayzam Shah of Malaysia ran 13.94s (-0.2) in Asian champs recently. Given a +1.0 tailwind he would have run 13.81s. Hence, we know that he actually has potential to run 13.72 - 13.75s (at his top form and given a great condition and tailwinds +2.0)
Long Jump / Triple Jump
Scientific research indicate that a +2.0 tailwind gives an improvement in long jumpers by at least 5cm and up to 16cm (men). However his best legal jump so far is 8.35m. From research, Bob Beamon's 8.90m benefited by the 2.0m/s tailwinds by approximately 16cm (and 12-14cm advantage from the altitude). Well, Fabrice Lapierre comes to mind as I witnessed him leaped a monster jump of 8.78m +3.1 in Perth in 2010.
I'm short of information on triple jump (will be updated later).
Statistics of wind reading in athletics meets
Ten (10) official results of athletics meets were randomly selected from the 2010/2011 athletics season for each of the following countries;
W.R.M = Wind Reading Measured
W.R.N.R = Wind Reading Measured (and results) Reported
From the figures above, wind reading were NOT measured in most of competitions in Southeast Asia. At the same time, some competitions that have measured the wind didn't report the results / reading. For instance, only 2 out of 10 competitions in Malaysia took some initiative to measure the wind, but unfortunately only one out of two reports the results / readings.
-Wind gauge is compulsory in track and field meets and the results must be reported along with the official results. If NOT, athletes and coaches do not know whether there is improvement in a performance. Therefore, track organizers should look at the matter seriously for the benefit of athletes and coaches. Besides, controlling the wind gauge is the easiest work in athletics meet.
A realistic quasi-physical model of the 100 metre dash by J.R. Mureika
A mathematical analysis of the bioenergetics of hurdling by A.J Ward-Smith
A model of wind and altitude effect 110m hurdles By Spiegel & Mureika
The legality of wind and altitude assisted performances in the sprints by J.R Mureika
Effects of winds on world class long jump performance by David W. Murrie
What really are the best performances? J.R. Mureika
Comparing 100m sprints by K. Duffy