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PROTRACK » GENERAL » Adjusted times

Adjusted times

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1 Adjusted times on Tue Mar 13, 2018 10:00 pm

Slowcoach


I have raised my concerns previously about wind adjusted times. Firstly the accuracy of the reading and secondly the adjustment calculation.

I stand to be corrected, but I believe the wind reading is taken once at a specific time during the race. (usually 10 seconds into the race for a sprint)

How can anyone be sure the wind was constant at that speed for the whole race? What if there was a gust just at the time of the reading ??

If the VAL are adamant they want to use wind adjusted times, the speed should be measured at least 3 or 4 times during the race and averaged.

Secondly, the calculations are clearly flawed. Womens races especially (with their lighter frames) seem to be impacted much more by either head or tails winds.

Times below from the Bendigo women’s 120m semi’s.

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The variation from the heat times on Saturday (with a tail wind) to their semi times with a head wind are way too big to be considered anywhere near accurate.

In addition the girls in the first semi are clearly disadvantaged. The stronger wind (-2.2 compared with -1.2) obviously impacted more on their runs than the calculation allows.

Something has to be done here. If we can’t get more precise wind readings and a more accurate adjustment factor, we should just use raw times.

Personally I think once it gets to the semi stage, it should be placings only that progress to the final.

The other concern is NAP's and UP's can be issued based on this flawed information.

2 Re: Adjusted times on Tue Mar 13, 2018 10:38 pm

ToM

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“Basic rules of wind gauge operation
For sprints and hurdles, the anemometer (wind gauge) must be placed at 50m mark (just adjacent to lane 1) before the finish line. It should be measured (to start recording) from the start of race (100m - 10s duration and 110mh - 13s), or the last 100m for the 200m event (10s duration). You don't have to worry when do you stop it, it will operate (when you push button for the manual wind gauge) and stop automatically (pre-set the duration). ”
http://www.adriansprints.com/2011/08/importance-of-wind-gauge-in-track-meet.html?m=1

Also http://athletics.com.au/Portals/56/Officials/Wind%20Gauge.pdf

And http://westoncreekathletics.org.au/wp-content/uploads/2016/02/regulations_for_wind_gauge_calibration.pdf



Last edited by ToM on Tue Mar 13, 2018 11:11 pm; edited 1 time in total

3 Re: Adjusted times on Tue Mar 13, 2018 10:41 pm

ToM

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.



Last edited by ToM on Tue Mar 13, 2018 11:12 pm; edited 1 time in total

4 Re: Adjusted times on Tue Mar 13, 2018 10:58 pm

ToM

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If you would like to look more in depth at the effect of wind on performance, I would suggest http://www.humankinetics.com/acucustom/sitename/Documents/DocumentItem/10582.pdf
There is a particularly good graph on page 114 that compares the effects of head and tailwinds of varying velocities from different models against their advantage and disadvantage.

Key quote:
“The rate of improvement in race time gradually decreased with increasing wind velocity, and so the disadvantage of a head wind was greater than the benefit of a tail wind of the same magnitude. The advantage of a 2-m/s following wind was 0.10 f0.01 s for the male sprinters and 0.12 +- 0.02 s for the female sprinters.”

Each of the models agree that a tailwind provides diminishing benefit as the velocity increases, and that a headwind provides increasingly larger disadvantage as the wind increases.

5 Re: Adjusted times on Tue Mar 13, 2018 11:09 pm

ToM

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I have used the above and following information in the past to discuss an NAP one of my athletes received due to extreme tailwinds. The flaw is that the VAL model is linear where as the best predictive models suggest it will flatten out as tailwinds increase. The stewards were receptive to the information and overturned the four NAPs involved.

Source: Loyola Marymount Wind Speed Calculator by Jonas Mureika
MUREIKA, J.R. (2001) A Realistic Quasi-physical Model of the 100 Metre Dash. Canadian Journal of Physics, 79 (4), p. 697-713

6 Re: Adjusted times on Tue Mar 13, 2018 11:10 pm

ToM

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7 Re: Adjusted times on Wed Mar 14, 2018 9:09 pm

Slowcoach


Thanks ToM for the information. Sounds like the wind readings should be correct, but I still find them hard to believe sometimes!. Calibration of the gauge is something that needs to be done regularly.

The research in these articles confirms my thought on the adjustment calculation. Perhaps the VAL linear model should be reviewed, as clearly it doesn't correctly reflect the athletes performances.

8 Re: Adjusted times on Thu Mar 15, 2018 1:24 pm

auspro


You know its accurate when the same calculation is used (2m/s=0.1s) for both the 70m and 120m.Laughing

There is only one valid reason to use adj times and that is to discourage athletes running 'easy places' to advance.

9 Re: Adjusted times on Fri Mar 16, 2018 9:42 pm

Mex

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It is in our guidelines and whether individuals like it or not it is there to stay. The year they went with raw times saw non competitive finals the way I saw it. I personally like that there is a constant that we can use. Perhaps our discussion should not be one whether the adjusted times should be used or not but rather to work out what the adjustment should be. I am sure that if we could look at the data for each event that uses the wind guage we would find that the constant could be different for 70m events, open 120m events and both men only or women only 120m events. I think that if we start a process of multiple constants we run the risk of it becoming too hard for the officials so I will go back to my original thoughts. I like having a constant that everyone is aware of before we even turn up. It has worked for me and against me, for and against my athletes. But it is clearly in our guidelines.

I would prefer to look at the handicapping system before adjusted times. Too many are getting out to big marks early in their careers. But that is for another day during winter when I have nothing better to do than watch old film and relive the glory days.

10 Re: Adjusted times on Fri Mar 16, 2018 10:18 pm

Slowcoach


Appreciate your point of view Mex, but when every single semi final runner loses time from the heats, and all the non-finalists get an NAP, the system surely must be looked at.

11 Re: Adjusted times on Sat Mar 17, 2018 10:22 am

youngy

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Recently Leigh Phelan ran the fastest (raw) heat time at Doncaster but on adjusted times he was 3rd fastest. Phelan won the final.

I don't have an issue  with using adjusted times for advancing athletes to semis/finals or as a guide when assessing marks.

My issue is the distortion of times in a historical context. For over 120 years the raw time was that recorded as the official time of the winner. This has been the case in any form of athletics in the world - IAAF, every pro running league anywhere, school sports, Little A's etc.

However the VAL, for reasons that seem only apparent to the few who insist upon it, they have chucked the whole concept of time on its head by using adjusted times as the official time.

The wind reading is an estimate only - it's not 100% accurate. Until they come up with a wind reading that is fool proof and accurately assesses the wind for every lane, then I think the wind adjusted time is just an estimated time only and not the actual time recorded.

By all means, offer the wind reading, but I would much prefer the raw time be the official time.



Last edited by youngy on Sat Mar 17, 2018 2:15 pm; edited 1 time in total


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12 Re: Adjusted times on Sat Mar 17, 2018 2:07 pm

Fast


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We have discussed wind adjusted false times so many times and how ridiculous it is that they determine - official historical times, progression to finals, stewarding decisions and handicapping.

It is time some intelligence and reasonableness prevails and the controlling minority in the VAL who are delusional about adjusted false times are moved on.

The use of adjusted false times was ridiculously highlighted in the Women’s Gift at Bendigo where all the girls that failed to make the final were given NAP’s because of the changing wind conditions across the two days.

Holly Dobby for example was sanctioned with a NAP for running a head wind PB rpm, if you run a PB and get a NAP what message is that sending.

Unfortunately, the Stewards and handicappers hands are tied as they are ridiculously forces to uphold illogical and poorly thought out rules that are based on false adjusted times.

VAL Rules -Unfortunately with the current VAL handicap system any loss of time (based on false adjusted times), through progression, of over 1 metre is considered a NAP. The stewards/handicapper’s hands are tied in this respect, as there are three grades of assessment for athlete’s performances, NAP, AP and UP.



Most who have an understanding of sprinting, conditions and wind clearly know that false adjusted times are only at best a very rough guide.

The bigger problem is the integrity of the VAL data base when false times are the basis of handicapping.

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