Contador's Power Numbers on Mt. Etna

[roundabout]

You've rather changed the point of attack here I'm afraid.

I've very little interest in discussing whether Bertie dopes - the point I'm making, which you can disagree or agree with on its own terms as you please, is that the margin of victory yesterday was not some jaw-dropping, flabbergasting, baffling margin. Unless we have very different understandings of these words, I would suggest the results you already posted confirmed the point I made.

On your broader point, it's instructive to discover bike races can't be won by 50 seconds without doping, ta for the tip off. I would note that anyone giving a mid-90's level of performance on etna yesterday would have won by several minutes, over and above Contador.

Right, so stages finishing with smaller gaps 86% of the time mean that Contador's superiority wasn't baffling. Can I get the exact number where I would be ok to use those terms? Thank you.

 

[ergmonkey]

ya contador isn't exactly great passing himself diesel style and keep gaining time (like sastre in 2008 or basso last year) he just snaps does a few meters at an insane speed and then keeps a good enough speed not to lose anytime. he certainly looks to struggle on the bike when he is on the saddle. andy is a better diesel but he just can't drop contador.

This seems to be more or less true to me. The interesting point for me, though, is that despite these climbing characteristics, Schleck is so much worse than Contador in the ITT.

You'd think that the guy who prefers to power away steady and in the saddle could figure out how to TT against the guy who only looks to be at his most comfortable when he's dancing out of the saddle for strong bursts.

Makes me think that looks can be deceiving, and Schleck probably isn't so much better than Contador at steady climbing, even as a diesel.

 

[Lanark]

This seems to be more or less true to me. The interesting point for me, though, is that despite these climbing characteristics, Schleck is so much worse than Contador in the ITT.

You'd think that the guy who prefers to power away steady and in the saddle could figure out how to TT against the guy who only looks to be at his most comfortable when he's dancing out of the saddle for strong bursts.

Makes me think that looks can be deceiving, and Schleck probably isn't so much better than Contador at steady climbing, even as a diesel.

Don't underestimate the huge influence aerodynamics have in an ITT. I'm pretty sure that the Rabobank-site last year said that the power ratings showed Gesink produced more power during the Tour ITT than Menchov, yet he lost almost 5 minutes, al due to aerodynamics. Of course, that was an exceptionally windy and flat time trial, but that could easily explain the difference in time trial ability between Schleck and Contador, despite being pretty much equal climbers.

 

[ergmonkey]

Don't underestimate the huge influence aerodynamics have in an ITT. I'm pretty sure that the Rabobank-site last year said that the power ratings showed Gesink produced more power during the Tour ITT than Menchov, yet he lost almost 5 minutes, al due to aerodynamics. Of course, that was an exceptionally windy and flat time trial, but that could easily explain the difference in time trial ability between Schleck and Contador, despite being pretty much equal climbers.

Definitely, aerodynamics can be a huge ITT factor. With A. Schleck, though, I think there's more to it than just that. Sure, his position has never looked like a great one; but I would also suggest that he has never looked powerful riding the TT bike, either.

I suspect that being able to generate his best power numbers in the TT position is at least as big a problem for A. Schleck as the aerodynamics of his TT position.

 

[Escarabajo]

I'll say let's wait for numbers in the Zoncolan. These numbers are not so impressive for the whole 20 km.

I did a rough estimate (using the climbbyke information) for the last 7 kms and I got the following:

Time: 19.43 minutes (20.7 minutes Verbier)
Length: 7 kms (8.7 kms Verbier)
Gradient: 6.11% (7.5% Verbier)
Wind: head (Verbier slight tailwind)
Power: ~410 Watts (~430 watts Verbier)
Power/Kg ratio: 6.7 Watts/kg (~7-7.1 watts/kg)

Of course if we take into consideration that the wind is big factor on the drag power the error on these two numbers could mean that Contador is on par with his performance on Verbier. For these assumptions taken here his performance is below his 2009 Tour de France form.

I assumed that he started his attack when the gradient kicked to 7.1% just about 7 kms from the finish.

One last comment. His Verbier performance was at the end of the second week. This performance is at the end of the first week of racing. This can make a big difference on the numbers.

http://www.climbbybike.com/map.asp?qryMountainID=2118&Region=Nicolosi&Country=Italy

http://www.climbbybike.com/profile.asp?Climbprofile=Etna---Rifugio-Sapienza&MountainID=2118

 

[Escarabajo]

I saw the other thread. Maybe moderators can merge these two threads.

My numbers are slightly higher. I think my drag coefficients are slightly higher also.

I am using the same power numbers from Verbier that LeBreton presented here a while ago. I did my calculations and agreed with it. So numbers are lower for ETNA (6.7 watts/kg versus 7 watts/kg)

I really don't like to use VAM numbers because of the wind miscalculation.

 

[Race Radio]

I'll say let's wait for numbers in the Zoncolan. These numbers are not so impressive for the whole 20 km.

I did a rough estimate (using the climbbyke information) for the last 7 kms and I got the following:

Time: 19.43 minutes (20.7 minutes Verbier)
Length: 7 kms (8.7 kms Verbier)
Gradient: 6.11% (7.5% Verbier)
Wind: head (Verbier slight tailwind)
Power: ~410 Watts (~430 watts Verbier)
Power/Kg ratio: 6.7 Watts/kg (~7-7.1 watts/kg)

Of course if we take into consideration that the wind is big factor on the drag power the error on these two numbers could mean that Contador is on par with his performance on Verbier. For these assumptions taken here his performance is below his 2009 Tour de france form.

I assumed that he started his attack when the gradient kicked to 7.1% just about 7 kms from the finish.

One last comment. His Verbier performance was at the end of the second week. This performance is at the end of the first week of racing. This can make a big difference on the numbers.

http://www.climbbybike.com/map.asp?qryMountainID=2118&Region=Nicolosi&Country=Italy

http://www.climbbybike.com/profile.asp?Climbprofile=Etna---Rifugio-Sapienza&MountainID=2118

The wind yesterday was strong, which makes Contador's performance even more impressive. The 2nd group worked together and got nowhere. 21 kmph with a headwind sharing the work helps. It looked like AC was climbing in his 39x16 or 15 at a high rpm.

 

[Jan the Man]

Yes the gap was impressive but people must also remember that Contador was riding against an un-coordinated group-

When he was with Scarponi- Nibali was leading the chase and setting a tempo, from memory dragging a substantial group of 10-15 along with him. There was then a lull until Scarponi rejoined when Niemenc eventually took on the pace setting.

He was setting a good pace but not unbareable as the group was still 10-15 riders and not really shelling anyone. Gadret/Kreuziger then put in a couple of digs at which point Niemec closed the gap and peeled off. There was then another lull until Niabli launched himself with about 500m of the climb left.

The point being Contador was riding probably 95-100% limit all of the time. The chasing group while putting in a couple of bursts were for a significant period not riding a tempo and changing pace. If they would have been co-ordinated and in particular Nibs and Kreuziger ridding together then the gap would have been smaller.

Gaps are often increased by tactics rather than someone being necessarily stornger than the other. Statistics aren't an answer to every question.

Having said this, Contador clearly was the best climber in the world coming into the Giro, and proved that yesterday at the Giro.

 

[thehog]

The wind yesterday was strong, which makes Contador's performance even more impressive. The 2nd group worked together and got nowhere. 21 kmph with a headwind sharing the work helps. It looked like AC was climbing in his 39x16 or 15 at a high rpm.

Contador did say he attacked at 7km because there was no wind with the mountain coverage until about 4.5km to go.... he gained 40s then 50s very quickly then maintained that time. It was a tactic rather than trying to smash it into the wind from a long way out.

 

[veganrob]

Putting aside the time gaps from 1st to 3rd or whatever, can someone explain to me why the weight of the bike is not factored in power numbers. Granted, the numbers have nothing to do with time put on opponents, but just interested in the calculations.
I teach power training on computrainers in winter so I am curious.
Thanks

 

[Semper Fidelis]

WoW

WoW how can any of these numbers be accurate?
Are these numbers from television coverage? WoW.

 

[Escarabajo]

Putting aside the time gaps from 1st to 3rd or whatever, can someone explain to me why the weight of the bike is not factored in power numbers. Granted, the numbers have nothing to do with time put on opponents, but just interested in the calculations.
I teach power training on computrainers in winter so I am curious.
Thanks

Bike weight is taken into account. It is 6.8 kgs aprox. We usually put an extra 1 kg due to other related weights like water in the bottle. So total extra weight is around 7.8-8 kgs.

I fixed my initial post because I had not realized that I did not write the bike weight. But it was taken into account in the calculation.

 

[veganrob]

Bike weight is taken into account. It is 6.8 kgs aprox. We usually put an extra 1 kg due to other related weights like water in the bottle. So total extra weight is around 7.8-8 kgs.

I fixed my initial post because I had not realized that I did not write the bike weight. But it was taken into account in the calculation.

Ah, I didn't see that. Thank You

 

[Siriuscat]

Don't forget with all those switchbacks and hairpins, he'd have had a tailwinds at times too.

 

[roundabout]

Don't forget with all those switchbacks and hairpins, he'd have had a tailwinds at times too.

Are you worried about the plausibility of Contador's performance or concerned that the estimate might be off?

Or both?

 

[Mrs John Murphy]

Contador did say he attacked at 7km because there was no wind with the mountain coverage until about 4.5km to go.... he gained 40s then 50s very quickly then maintained that time. It was a tactic rather than trying to smash it into the wind from a long way out.

In the words of Mandy Rice-Davies: 'He would say that wouldn't he'.

It's highly unlikely he would turn around and say 'yes there was a strong headwind but it was no match for me'.

For those on the 'Conspiracy Line' there was also the 'special' planned bike change as well before the climb.

 

[sniper]

great, so a couple of years have passed now, and we still don't know what program Dirtie is on. Anybody?
I still put my money on HGH and/or genetic doping (approved from higher up?). Indeed, in addition to microdosed blooddoping.

 

[Siriuscat]

Are you worried about the plausibility of Contador's performance or concerned that the estimate might be off?

Or both?

Niether to be honest, the numbers provided by others seem sensible it was just a simple fact to help the accuracy for those that need or want it.

 

[theswordsman]

I don't belong in these types of discussions, but I'll toss in that Contador did a planned bike change with 30 kilometers to go. In an Andrew Hood article at Velonews it was described as "lighter". Also, one of his competitirs - I think off the top of my head it was Kreuziger - said he noticed what a big gear Contador was in as he attacked. That's as close as I get to technical conversations. Cheers

 

[Epicycle]

Wind: head (Verbier slight tailwind)

The wind on the Etna climb yesterday changed with the switchbacks. For example, on the section Contador dropped Rujano they had a strong tailwind. It's probably hard to gauge the overall effect of a strong wind on a climb with switchbacks, to really pin it down you'd have to figure out the wind direction and steepness for the different sections. Also yesterday they had a wall on the uphill side of different sections so it might have shielded the wind like Contador talked about.

I know we had the same discussion about one of Contador's attacks in 2009, I think it was after his attack on the Arcalis climb. There was a strong wind but it changed with the switchbacks.

 

[halamala]

Dr. Michele Ferrari:

Giro d' Italia 2011 - Etna Stage
By: Michele Ferrari
Published: 16 May 2011

It took 6 minutes 28 seconds for Alberto Contador to ride between km 6 and km 3 to the finish line, at the average speed of 28.1 km/h.

The VAM = 1821m/h on the average gradient of 6.5% required an average power output of 6.87 w/kg, equal to 426 watts assuming a body weight of 62 kg.

The ascent was affected by strong winds, therefore the expressed power was probably even higher, although it is quite difficult to quantify.

http://www.53x12.com/do/show?page=indepth.view&id=117

 

[python]

Dr. Michele Ferrari:http://www.53x12.com/do/show?page=indepth.view&id=117

given the source, I would not take it as much.

contador may still be blood doping, why would anyone would be surprised, but there is a clear pattern in the anti-conta gang (no, not in the forum but the former associates of his 'multi-winning teammate') - spin his performance.

ferrari's estimate, to deserve more attention, needs to break the entire solo ride into the sections/segments with individual wind conditions and slopes...or provide the performance estimate of the pursuants on the same section he chose to evaluate contador. finally, like most analysis here, he failed to provide the +/- tolerance around his estimates.

 

[Merckx index]

Ferrari's numbers don't seem very consistent with those posted on the other climbing thread. On that thread it was stated that Bert climbed from km 8 to km 1 in 17:10, a 6.6% gradient. This gives a VAM of 1628 and power of 6.17 watts/kg (we have discussed effects of other factors, including wind, on that thread).

If both of these sets of numbers are correct, then it took Bert a cumulative 10:42 to climb the 4 km from 8-6 then 3-1. With a vertical climb of 271, this is a VAM of 1520 and power of about 5.70 watts/kg. I gather from the numbers that the grade was pretty consistently 6-7% throughout that stretch (?), so it doesn't make sense that there would be this much difference. Either he slowed down in one of these stretches then put on a burst of speed later, or one of those times (6:28, 17:10) is likely wrong.

finally, like most analysis here, he failed to provide the +/- tolerance around his estimates.

At the level Ferrari is working at, just using VAM, the error or tolerance should be very small. Only two numbers are involved, height in meters and time. While a mistake in time could be made (not recording at the proper km markers), assuming it wasn't, the error in a stopwatch recording is obviously minuscule. The height in meters I would think would also be quite accurate, since this is a well-known climb.

 

[Escarabajo]

The wind on the Etna climb yesterday changed with the switchbacks. For example, on the section Contador dropped Rujano they had a strong tailwind. It's probably hard to gauge the overall effect of a strong wind on a climb with switchbacks, to really pin it down you'd have to figure out the wind direction and steepness for the different sections. Also yesterday they had a wall on the uphill side of different sections so it might have shielded the wind like Contador talked about.

I know we had the same discussion about one of Contador's attacks in 2009, I think it was after his attack on the Arcalis climb. There was a strong wind but it changed with the switchbacks.

You are right. You need almost to be there and measure at different points. It is very hard. Option is calculating extreme conditions with 100% head wind and 0% head wind and find the range. You know you are going to be there somewhere in the middle.

 

[Escarabajo]

Dr. Michele Ferrari:http://www.53x12.com/do/show?page=indepth.view&id=117

Thanks Halamala.

I am not sure how Ferrari got to those numbers? I don't get his numbers using VAM.

I'll stick with my 6.7 watts/kg for the 7 kms stretch.