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Power Data Estimates for the climbing stages

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18-Valve. (pithy) said:
Giro d'Italia 2007, stage 17, Monte Zoncolan, power data estimates

http://letour.over-blog.com/article-10643112.html

Gilberto Simoni
Durée = 2020s
Distance = 8000 mètres
Vitesse = 8000/2020 = 3,96 m/s
Masse = 58 kg + 9 kg (vélo)
W = 0,24*v*v*v + 0,137*m*v + 9,81*v*m*p
W = 0,24*3,96*3,96*3,96 + 0,137*67*3,96 + 9,81*3,96*67*0,1319
W = 14,9 + 36,3 + 343,3
W = 394,5 Watts
W par kg = 394,5/58 = 6,80 Watts/kg
-----------
If you look at these calculations you see that several coefficients are way off the mark.

the 0.24 for example, which corresponds to 0.5*air density*CdA, should be roughly
0.5*1.03*0.37 = 0.19 which reduces the 14.9 watts to under 11.8 watts

worse yet
the coefficient of rolling resistance (Crr) in the second term ( 0.137) is 30 to 40 times too large, but in fact the blogger used 0.0137, only 3 to 4 times too large. Anyway a realistic value for a nice asphalted road would be a bit below 0.004
This reduces the second term from 36.3 to 10.6 watts
Thankfully no mistake is visible in the main term.

Assuming the altitude gain by Simoni in 2007 was as stated 1055 meters over the last 8km of Zoncolan climbed in 2020 seconds, we get a total wattage of
11.8 + 10.6 + 343.3 = 368.4 watts for 58 kg of body weight, ie 6.35 watts/kg.

You can although throw in the transmission losses and increase those figures by +2.5% and get 377.6 watts and 6.51 watts/kg.

But then you can also assume that his bike + cloth+ whatever amounted only to 8 kg , not 9 kg and reduce the 2nd and 3rd terms by a total of 5.3 watts and about 0.1 watts/kg.

Now the biggest uncertainty for someone like me who does not know that climb comes from the altitude difference between the finish line and the 8km from the finish point.

I don't know why the blogger decided to use the last 8km rather than the 10km used by the germain website rst.mp-all.de

Anyway, over the full 10 km 1 minute slower than Simoni2007 means about 0.16 watts/kg less for a ~60kg cyclist
Contador- Nibali were about 2 min. slower, ie about 0.3 watts/kg below.
 
roundabout said:
Hmm, supposing that Bruseghin did the 10 km in 41.56 and he was 1.57 behind at the finish would mean that Simoni was a little under 40 minutes in 2007 which is a lot slower than usually given for that climb.

Post number394 gives
Simoni is a record holder: 38:59, Giro 2007 (last 10 Km). Basso's time was 40:17 in 2010 (last 10 Km).

So the difference must be 2:57 not 1:57
 
roundabout said:
Hmm, supposing that Bruseghin did the 10 km in 41.56 and he was 1.57 behind at the finish would mean that Simoni was a little under 40 minutes in 2007 which is a lot slower than usually given for that climb.

http://letour.over-blog.com/article-10643112.html
I went to see that blog

The discrepancies I mentioned come from 2 main factors
1) the blogger forgets that air density varies with altitude (and temperature)

2) The blogger did a typo : the rolling resistance, which he intended to consider as 0.004 - a perfectly reasonable value - has thus become an outrageous 0.014.

(The 0.137 comes from associating the g of gravity with the rolling resistance rather than with the mass of the rider, amusing but not leading to additional errors)
 
Your points seem reasonable to me.

However, there also seems to be a problem with measuring the time it took for riders to climb the Zoncolan. I have doubts that it would take over 6 minutes (6.19 give or take based on 33.40 it took Simoni to do the final 8km, 41.56 as time given for Bruseghin over 10km and the difference at the finish between them of 1.57) to cover 2 km at 7.5% (the first 2 km of theclimb from 10 to 8 to go with 675-525=150m altitude gain according to the blog) for climbers like Simoni, Schleck etc in 2007. Instinctively it seems a little slow.
 
roundabout said:

I didn't read the whole article to see if Bruseghin started the climb with 1 min advantage, probably not the case. So, Bruseghin must have climbed in 39:O5 + 1:57 =41:02

Why? the time given in the CN article for Simoni is 39:05
It also happens to be - within 1 second - his time according Portoleau and cyclismag (39:04)

http://www.cyclismag.com/article.php?sid=5542

see under 17e étape
 
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Useful information: Giro d'Italia 2007 - Cyclismag.com

Giro5_20070630160649.gif


(*)Etalon de 78 kg avec vélo
Nous ne calculons pas la puissance réelle développée par les coureurs. Celle-ci dépend entre autre de la masse à élever pour vaincre la pente. Le poids des coureurs n'est pas toujours connu avec précision le jour de la mesure. Ils peuvent se déshydrater en cours d'étape et perdre quelques kilogrammes. Le nombre de bidons portés est variable. Pour toutes ces raisons, nous préférons calculer la puissance d'un « coureur étalon » de 70 kg avec un équipement de 8 kg. Cette valeur est utilisée pour faire nos comparaisons.


Sorry, I can't translate it in English.
 
halamala said:
Useful information: Giro d'Italia 2007 - Cyclismag.com

Giro5_20070630160649.gif


(*)Etalon de 78 kg avec vélo
Nous ne calculons pas la puissance réelle développée par les coureurs. Celle-ci dépend entre autre de la masse à élever pour vaincre la pente. Le poids des coureurs n'est pas toujours connu avec précision le jour de la mesure. Ils peuvent se déshydrater en cours d'étape et perdre quelques kilogrammes. Le nombre de bidons portés est variable. Pour toutes ces raisons, nous préférons calculer la puissance d'un « coureur étalon » de 70 kg avec un équipement de 8 kg. Cette valeur est utilisée pour faire nos comparaisons.


Sorry, I can't translate it in English.

Yes, that's the link I was giving
The note at the bottom just says that the powers are normalized for a 70kg cyclist with 8kg equipment and various warnings such as : variations in body weight do occur during a stage, etc.
 
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Gardeccia-Val di Fassa: Contador climbed 5.9 W/kg, Scarponi 5.8 W/kg

Giro d'Italia 2011, Stage 15, Final climb Gardeccia-Val di Fassa

Alberto Contador

Elevation / Höhenmeter [m] : 618 m
Distance / Streckenlänge [Km] : 6.15 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1307 = 21 min 47 sec = 21:47
Weight rider / Gewicht Fahrer [kg] : 62 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 10.0 %
Average speed / mittlere Geschwindigkeit : 16.9 Km/h
Total weight / Gesamtgewicht : 70.0 kg

Power : 366.5 Watt
Power / kg : 5.9 Watt / kg


Michele Scarponi

Elevation / Höhenmeter [m] : 618 m
Distance / Streckenlänge [Km] : 6.15 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1313 = 21 min 53 sec = 21:53
Weight rider / Gewicht Fahrer [kg] : 63 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 10.0 %
Average speed / mittlere Geschwindigkeit : 16.8 Km/h
Total weight / Gesamtgewicht : 71.0 kg

Power : 369.5 Watt
Power / kg : 5.8 Watt / kg


Source: [ http://www.rst.mp-all.de/bergauf.htm ]
 
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especially a good performance by Scarponi, think he could have performed way better at Etna and Großglockner if he had stayed at his own rhythm instead of trying to follow Contadors attacks.
 
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Nevegal TT: Contador climbed 6.3 W/kg

Giro d'Italia 2011, Stage 16, ITT, Final climb Nevegal

Alberto Contador


Elevation / Höhenmeter [m] : 600 m
Distance / Streckenlänge [Km] : 7.3 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1258 = 20 min 58 sec = 20:58
Weight rider / Gewicht Fahrer [kg] : 62 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.2 %
Average speed / mittlere Geschwindigkeit : 20.8 Km/h
Total weight / Gesamtgewicht : 70.0 kg

Power : 395.5 Watt
Power / kg : 6.3 Watt / kg


Source: [ http://www.rst.mp-all.de/bergauf.htm ]
 
halamala said:
Giro d'Italia 2011, Stage 16, ITT, Final climb Nevegal

Alberto Contador


Elevation / Höhenmeter [m] : 600 m
Distance / Streckenlänge [Km] : 7.3 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1258 = 20 min 58 sec = 20:58
Weight rider / Gewicht Fahrer [kg] : 62 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.2 %
Average speed / mittlere Geschwindigkeit : 20.8 Km/h
Total weight / Gesamtgewicht : 70.0 kg

Power : 395.5 Watt
Power / kg : 6.3 Watt / kg


Source: [ http://www.rst.mp-all.de/bergauf.htm ]

Can someone verify that the elevation is really 600m? and the time 20:58?
Also, what was the temperature?

The main disturbing factor to consider after the above details are ascertained is the nearly flat sector, about 1km long, near the finish.
http://www.cyclingnews.com/races/giro-ditalia-his/stage-16

It results in a loss of about 1 1/2 minutes with hardly any altitude gain.

Interesting to note that the effort duration is comparable with Verbier.
 
no need to be in the clinic

Le breton said:
Can someone verify that the elevation is really 600m? and the time 20:58?
Also, what was the temperature?

The main disturbing factor to consider after the above details are ascertained is the nearly flat sector, about 1km long, near the finish.
http://www.cyclingnews.com/races/giro-ditalia-his/stage-16

It results in a loss of about 1 1/2 minutes with hardly any altitude gain.

Interesting to note that the effort duration is comparable with Verbier.

OK, nobody wants to do it, so I guess I have to.
Over the last 7000m, there are 2 sections which are nearly flat
1) from -1300meters to -1000m @ 2.8%
2) from -1000m. to -400m.@ 0.8%

To do a proper power estimate for the remainder of the climb, we need to remove those bits, 900m. in total.

Assuming Contador reduced his power a few% to 380 watts on those easier stretches, and adopted a lower crouched position (CdA ~0.32 m^2) he needed 30.5 s for section 1) and 50.5 s for section 2)

So for the remainder of the climb, ie for 7300-900 = 6400meters
with a total elevation of 600-13m = 587 meters (9.17%)

he needed 20:58 - 1:21 = 19:38 = 1178s.

ave. speed = 5.433 m/s

taking air density = 1.09

CdA = 0.375 m^2

Crr = 0.004

We end up with 390 watts.

Add 2.5% for transmission losses

390 + 2.5% = 400 watts

ie 400 / 62 = 6.45 watts /kg.

For an all out 20-30 minute effort after 1 day of rest.

In other words, we are at a performance level implying that this post does not need to be in the clinic.

Of course it also seems to imply that past performances were out of this world.
 
Le breton said:
...

390 + 2.5% = 400 watts

ie 400 / 62 = 6.45 watts /kg.

For an all out 20-30 minute effort after 1 day of rest.

In other words, we are at a performance level implying that this post does not need to be in the clinic.
Of course it also seems to imply that past performances were out of this world.
For a third week in this Giro? I think is borderline, don't you think?
 
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Re-calculation (Nevegal): Contador 6,4 W/kg, Scarponi 6,1 W/kg, Nibali 6,0 W/kg

Re-calculation

Giro d'Italia 2011, Stage 16, ITT (profile), Final climb Nevegal, from 7.3 Km remaining to 3.0 Km remaining (Distance : 4.3 Km)

Alberto Contador

Elevation / Höhenmeter [m] : 446 m
Distance / Streckenlänge [Km] : 4.3 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 868 = 14 min 28 sec = 14:28
Weight rider / Gewicht Fahrer [kg] : 62 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 10.3 %
Average speed / mittlere Geschwindigkeit : 17.8 Km/h
Total weight / Gesamtgewicht : 70.0 kg

Power : 399.8 Watt
Power / kg : 6.4 Watt / kg


Michele Scarponi

Elevation / Höhenmeter [m] : 446 m
Distance / Streckenlänge [Km] : 4.3 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 908 = 15 min 08 sec = 15:08
Weight rider / Gewicht Fahrer [kg] : 63 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 10.3 %
Average speed / mittlere Geschwindigkeit : 17.0 Km/h
Total weight / Gesamtgewicht : 71.0 kg

Power : 384.8 Watt
Power / kg : 6.1 Watt / kg


Vincenzo Nibali

Elevation / Höhenmeter [m] : 446 m
Distance / Streckenlänge [Km] : 4.3 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 917 = 15 min 17 sec = 15:17
Weight rider / Gewicht Fahrer [kg] : 63 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 10.3 %
Average speed / mittlere Geschwindigkeit : 16.8 Km/h
Total weight / Gesamtgewicht : 71.0 kg

Power : 380.5 Watt
Power / kg : 6.0 Watt / kg


Source: [ http://www.rst.mp-all.de/bergauf.htm ]
 
halamala said:
Re-calculation

[Alberto Contador

Elevation / Höhenmeter [m] : 446 m
Distance / Streckenlänge [Km] : 4.3 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 868 = 14 min 28 sec = 14:28
Weight rider / Gewicht Fahrer [kg] : 62 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg
Power : 399.8 Watt
Power / kg : 6.4 Watt / kg


Michele Scarponi

Power : 384.8 Watt
Power / kg : 6.1 Watt / kg


Vincenzo Nibali

Power : 380.5 Watt
Power / kg : 6.0 Watt / kg[/U]

Source: [ http://www.rst.mp-all.de/bergauf.htm ]

Thanks for the info.
I used air density 1.10 (24°C, 667m a.s.l.)
CdA = 0.38
Crr = 0.004

and got
392 watts.

adding 2.5% for transmission losses
392 + 10 = 402 watts.

Result perfectly in line with what I estimated higher up.
402 / 62 = 6.48 watts/kg.

To answer Escarabajo's question : borderline?

WEll, let's compare to AdH 2004 climb by LA, not really a "grimpeur"
Point 1 was really at km 1.7 ( as i thought), hence at
~725 m.
Point 2 was 50m after hairpin No 7, hence at ~ 1395m, km
9.15.
.....
Distance = 7 450m
Elevation 670m
time 21:03 = 1263 sec
slope =0.0899
v = 7450/1263 = 5.899m/s
Air density 28°C 1100m altitude -> 1.03
CdA 0.4 m^2
Crr = 0.0036
-----
70 kg cyclist + 8 kg equipment ( bike, shoes,... 1/2
bottle)

RESULT = 464 watts
+ 2.5% transmission losses -> 476 watts over 21 min

476/70 kg = 6.79 Watts/kg

There was no wind on that section of AdH that day.
(Higher up the last racers had to contend with a very noticeable wind)
Using only that lower part between 725 and 1395 m one does not need to take altitude into consideration : effect on performance almost negligible.


Of course, at the end of that section LA still had 20 min of effort ahead of him, not just 6 1/2 min.

6.48 watts/kg is the same as the 6.5 watts /kg of Boardman over 1 hr ( According to very trustworthy Peter Keen, 442 watts, 68 kg)

I have thought that Boardman was a little bit beyond the border for Boardman.

So I would say that 6.48 watts/kg for the best cyclist for less than 30 minutes is just around where the border is, in other words not automatically suspect.

If Contador is currently the best cyclist, so be it.

I am not saying that Contador is clean, just that I don't find it surprising if the best cyclist in the world can pull that type of performance.

Of course this automatically casts a shadow over previous superior performances by the same Contador.

Doing a BACK OF THE ENVELOPE VO2 estimate
402 watts = 402/(78 to 80) = 5.02-5.15 liters O2 per minute
........................................81-83 ml/ min.kg

Implying a VO2 max of (81-83)/(0.92-0.95) = 85-90 ml/mn.kg.


The green sentences give just rough estimates, not hard estimates like above.
 
MrRoboto said:
So what numbers do we have on Contador's best performances (ever)?

According to cyclismag he produced 7.2 Watt/Kilo over 21 minutes in verbier 2009.
However, those numbers are a bit doubtful. Cause according to this calculations more or less every rider in the top 15 set a stunning new personal best in Watt/kg. So something must have helped performances this day? Maybe tailwind? Or just wrong calculations.
 
Le breton said:
...

To answer Escarabajo's question : borderline?

WEll, let's compare to AdH 2004 climb by LA, not really a "grimpeur"
Point 1 was really at km 1.7 ( as i thought), hence at
~725 m.
Point 2 was 50m after hairpin No 7, hence at ~ 1395m, km
9.15.
.....
Distance = 7 450m
Elevation 670m
time 21:03 = 1263 sec
slope =0.0899
v = 7450/1263 = 5.899m/s
Air density 28°C 1100m altitude -> 1.03
CdA 0.4 m^2
Crr = 0.0036
-----
70 kg cyclist + 8 kg equipment ( bike, shoes,... 1/2
bottle)

RESULT = 464 watts
+ 2.5% transmission losses -> 476 watts over 21 min

476/70 kg = 6.79 Watts/kg

There was no wind on that section of AdH that day.
(Higher up the last racers had to contend with a very noticeable wind)
Using only that lower part between 725 and 1395 m one does not need to take altitude into consideration : effect on performance almost negligible.


Of course, at the end of that section LA still had 20 min of effort ahead of him, not just 6 1/2 min.

6.48 watts/kg is the same as the 6.5 watts /kg of Boardman over 1 hr ( According to very trustworthy Peter Keen, 442 watts, 68 kg)

I have thought that Boardman was a little bit beyond the border for Boardman.

So I would say that 6.48 watts/kg for the best cyclist for less than 30 minutes is just around where the border is, in other words not automatically suspect.

If Contador is currently the best cyclist, so be it.

I am not saying that Contador is clean, just that I don't find it surprising if the best cyclist in the world can pull that type of performance.

Of course this automatically casts a shadow over previous superior performances by the same Contador.

Doing a BACK OF THE ENVELOPE VO2 estimate
402 watts = 402/(78 to 80) = 5.02-5.15 liters O2 per minute
........................................81-83 ml/ min.kg

Implying a VO2 max of (81-83)/(0.92-0.95) = 85-90 ml/mn.kg.


The green sentences give just rough estimates, not hard estimates like above.
Thanks LeBreton.:)

Sometimes I forget these are shorter efforts. Even Merckx did 6.4 watts/kg for the full hour I think.

Even Verbier was higher.

For LA I had somewhere around 6.5-6.6 watts/hr for the whole TT. That would call for doping for that length of time at the third week of the Tour.
 

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