Aviva London Grand Prix - Men's 100m heats

[JMT]

Official Results - Men - 100 Metres - Heat 1 - Wind : -1.5 m/s
Pos Athlete Nat Mark Pts
1 Yohan Blake JAM 10.18
2 Ivory Williams USA 10.18
3 Asafa Powell JAM 10.19
4 Trell Kimmons USA 10.41
5 Travis Padgett USA 10.48
6 Leevan Yearwood GBR 10.59
7 Mark Lewis-Francis GBR 10.70
James Ellington GBR DQ

Official Results - Men - 100 Metres - Heat 2 - Wind : -2.9 m/s
Pos Athlete Nat Mark Pts
1 Daniel Bailey ANT 10.26
2 Usain Bolt JAM 10.31
3 Simeon Williamson GBR 10.33
4 Craig Pickering GBR 10.47
5 Harry Aikines-Aryeetey GBR 10.50
6 Monzavous Edwards USA 10.55
7 Aaron Armstrong TRI 10.97
Tyrone Edgar GBR DQ

[stylee]

Blake and Bailey have looked so good lately.

To bad for Pickering - probably would have made the final if he had been in the other heat. Strange season for him.

And really too bad about the wind in general.

[stylee]

Pickering IS in the final. Way to go, stylee.

Bolt = 9.92 into -1.7, shutting down

[Track_man]

Powell 6th in 10.26?

[JMT]

Full Results

Official Results - Men - 100 Metres - Final - Wind : -1.7 m/s
Pos Athlete Nat Mark Pts
1 Usain Bolt JAM 9.91 20
2 Yohan Blake JAM 10.11 16
3 Daniel Bailey ANT 10.13 14
4 Simeon Williamson GBR 10.19 12
5 Ivory Williams USA 10.21 10
6 Asafa Powell JAM 10.26 8
7 Craig Pickering GBR 10.46 6
8 Trell Kimmons USA 10.47 4

[robin1]

@Track_man

Powell 6th in 10.26?

He was never really in contention and gave up on the last 10m. His confidence will be at a record low going into worlds now.

[Chris6878]

@robin1

He was never really in contention and gave up on the last 10m. His confidence will be at a record low going into worlds now.

Yea Asafa done went from the fastest in da world to being the 3rd fastest in jamaica. Even though he fuckin gave up. Damn I hope he gets it together. He is not old enough to start going downhill.

[walrusgod]

http://www.youtube.com/watch?v=l3IzFKfsfDA

Powell looked much better in his heat, he shut it down pretty early. Race 13* by my count!

*Based on wikipedia, including relay legs.

[mortac8]

@robin1

He was never really in contention and gave up on the last 10m. His confidence will be at a record low going into worlds now.

Giving up in so many of his races lately must not be good for his appearance fees.

[Sevastocrator]

The above link is of a poor quality.

Try this one

http://www.youtube.com/watch?v=mKtNNqQgtbQ

It almost looked like Bolt was accelerating at around 80m mark a then changed his mind deciding that the race was over…?! LOL Powell is facing a real obstacle…on the second look… his start was poor, his acceleration was worse and his form was like he was falling apart…does anyone know what is going on with him?

9.91 into a head wind…would it be fair to translate this with no wind at 9.71sec?

If this is a correct assessment …imagine what Bolt could run if there was 1.9m/s tail wind, and if he runs flat out all 100m in peak condition?

[Youngy]

Sevo

Not stalking you just offering the following info:

The accepted ‘rule of thumb’ way of adjusting for wind is halving the reading and in the case of a head wind subtract it from the time recorded.

Therefore it’s a 9.82 wind adjusted time.

Of course the wind affects each athlete differently so it’s impossible to say exactly what the wind affect would be on Bolt - but it would be different to say Blake or Powell.

Generally though the stronger the wind the more ‘exponential’ the affect.

[robin1]

@Youngy

The accepted ‘rule of thumb’ way of adjusting for wind is halving the reading and in the case of a head wind subtract it from the time recorded.

That would be 9.91 - 0.85 - 9.06.
Just teasing; I know what you mean.

[Sevastocrator]

Thanks Youngy. NP with me mate even if you were… LOL

I hope you take these chit chats lightly because I do.

I was going by the performances of other two JAM who have been consistent lately. I think Bolt is ready to break the WR.

[Charlie_Francis]

@Youngy

Sevo

Not stalking you just offering the following info:

The accepted ‘rule of thumb’ way of adjusting for wind is halving the reading and in the case of a head wind subtract it from the time recorded.

Therefore it’s a 9.82 wind adjusted time.

Of course the wind affects each athlete differently so it’s impossible to say exactly what the wind affect would be on Bolt - but it would be different to say Blake or Powell.

Generally though the stronger the wind the more ‘exponential’ the affect.

It is exponential into a headwind but I’d put it much higher. I’d give it a full two tenths off a Sevastocrator says under any reasonable conditions and a bigger differential with a high legal tail- low 9.60s. He is just murdering the fields and we’ll see soon enough.

[Charlie_Francis]

The other point I forgot to make is that the faster you are, the more it affects you so the differential margin varies with the most at the top and the least at the lower end.

[rainy.here]

@Charlie_Francis

It is exponential into a headwind but I’d put it much higher. I’d give it a full two tenths off a Sevastocrator says under any reasonable conditions and a bigger differential with a high legal tail- low 9.60s. He is just murdering the fields and we’ll see soon enough.

Charlie, two full tenths is low 9.70s, not low 9.60s. Which did you mean?

While I know Mureika’s calculator is not always highly regarded here, it puts Bolt at 9.80 with no wind, and 9.71 with +1.9m/s, with no change to the altitude. I was skeptical of the calculator until I read through how it works, and now I think it does a pretty good job. It has a few problems (not all of them are mentioned here, some are part of further discussion):
-It requires you to enter an altitude, which it then uses to calculate a “corrected time”. If you want to know what it thinks someone would have run on the same track with a different wind (which is what I did for the numbers above), you have to play guess & test a little bit.
-It assumes a the same drag ratio for all runners, which isn’t true. Not everyone’s body shape is the same, and, the heavier someone is, the less of an effect drag becomes. These assumptions are not that significant.

See Canadian Journal of Physics 79, 697-713 (2001) at http://arxiv.org/pdf/physics/0007042v1.

The mathematical model produced, based on race data from 88OG, 97WC, and 99WC, gives the following splits for a 9.85 runner.

0.15
1.71
1.04
0.93
0.88
0.86
0.85
0.84
0.85
0.86
0.88

9.85

Something else that Charlie didn’t mention is that the effect of wind is stronger for headwinds than it is for tailwinds. Since the drag (force from wind) is proportional to the square of the difference in speeds (the speed of air that the runner actually feels), this results in a bigger change for headwinds.

Example (forgive me for getting technical here): At some point Bolt will be running at 12m/s. Consider the wind speeds of -2, 0, and +2. At -2, he will feel a 14m/s wind. At 0, he feels a 12m/s wind, and at +2, he feels a 10m/s wind.

Since the drag force is proportional the square of the speed:

-2m/s gives 14m/s, which gives 196
+0m/s gives 12m/s, which gives 144
+2m/s gives 10m/s, which gives 100

So, in normal wind we get 144.

This increases to 196 at +2m/s, which is a 36.1% increase in wind drag.
This decreases to 144 at -2m/s, which is a 30.6% decrease in wind drag.

[Charlie_Francis]

I meant 9.70s low for no to slight tail and low 9.60s with close to 2m tailwind

[Charlie_Francis]

@rainy.here

Charlie, two full tenths is low 9.70s, not low 9.60s. Which did you mean?

While I know Mureika’s calculator is not always highly regarded here, it puts Bolt at 9.80 with no wind, and 9.71 with +1.9m/s, with no change to the altitude. I was skeptical of the calculator until I read through how it works, and now I think it does a pretty good job. It has a few problems (not all of them are mentioned here, some are part of further discussion):
-It requires you to enter an altitude, which it then uses to calculate a “corrected time”. If you want to know what it thinks someone would have run on the same track with a different wind (which is what I did for the numbers above), you have to play guess & test a little bit.
-It assumes a the same drag ratio for all runners, which isn’t true. Not everyone’s body shape is the same, and, the heavier someone is, the less of an effect drag becomes. These assumptions are not that significant.

See Canadian Journal of Physics 79, 697-713 (2001) at http://arxiv.org/pdf/physics/0007042v1.

The mathematical model produced, based on race data from 88OG, 97WC, and 99WC, gives the following splits for a 9.85 runner.

0.15
1.71
1.04
0.93
0.88
0.86
0.85
0.84
0.85
0.86
0.88

9.85

Something else that Charlie didn’t mention is that the effect of wind is stronger for headwinds than it is for tailwinds. Since the drag (force from wind) is proportional to the square of the difference in speeds (the speed of air that the runner actually feels), this results in a bigger change for headwinds.

Example (forgive me for getting technical here): At some point Bolt will be running at 12m/s. Consider the wind speeds of -2, 0, and +2. At -2, he will feel a 14m/s wind. At 0, he feels a 12m/s wind, and at +2, he feels a 10m/s wind.

Since the drag force is proportional the square of the speed:

-2m/s gives 14m/s, which gives 196
+0m/s gives 12m/s, which gives 144
+2m/s gives 10m/s, which gives 100

So, in normal wind we get 144.

This increases to 196 at +2m/s, which is a 36.1% increase in wind drag.
This decreases to 144 at -2m/s, which is a 30.6% decrease in wind drag.

You’ve got all these calculations but they don’t mean shit in the real world and I can guarantee you of that.
Where was the wind coming from? A quartering wind is much worst but doesn’t register as higher. What was the wind meter picking up where it is situated? Winds swirl in stadiums.
What is the temp and humidity? What is the size and muscle mass of the athlete affected? Best you can really do is look at the positions and differences to the field and make a reasonable guess based on the results you’ve seen in reasonable conditions.
In Paris, which was almost no wind but far from ideal, 2nd and 3rd were 9.91 and 9.93. In London same guys were 2nd and 3rd with 10.11 and 10.13
Is that one tenth or is it two?

[Charlie_Francis]

Another example of wind adjustments is the womens’ 200m here. You really think the wind was helping them or even neutral?

[rainy.here]

@Charlie_Francis

Best you can really do is look at the positions and differences to the field and make a reasonable guess based on the results you’ve seen in reasonable conditions.
In Paris, which was almost no wind but far from ideal, 2nd and 3rd were 9.91 and 9.93. In London same guys were 2nd and 3rd with 10.11 and 10.13
Is that one tenth or is it two?

That is a good point. However, for someone like me, who doesn’t have your experience with elite runners beyond what I’ve picked up as a fan, do you think it’s a bad thing to use the Mureika calculator to get an approximation? I don’t believe in ‘basic’ times, but I will occasionally plug some numbers into the calculator to get an idea of what might have been, and take into consideration things like track (if known) and weather conditions. I would expect using it in addition to my gut feeling, would be more accurate than my gut feeling alone.

A agree about the 200m adjustment - it is unreliable for all the reasons you’ve given, in addition to the added complexity of not knowing wind direction, something that is very important when considering 200m times.