Power Data Estimates for the climbing stages

[Le breton]

This was discussed in the thread: What percentage gain does blood doping/epo actually give? As I summarized in post #33:

In which thread? Not this one.

 

[halamala]

Rodriguez climbed 6.7 W/kg

Criterium du Dauphine, Stage 6, Final Climb Le Collet d'Allevard

Joaquim Rodriguez

Elevation / Höhenmeter [m] : 961 m
Distance / Streckenlänge [Km] : 11.2 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1926 = 32 min 6 sec = 32:06
Weight rider / Gewicht Fahrer [kg] : 57 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.5 %
Average speed / mittlere Geschwindigkeit : 20.9 Km/h
Total weight / Gesamtgewicht : 65.0 kg

Power : 385.0 Watt
Power / kg : 6.7 Watt / kg

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

 

[18-Valve. (pithy)]

Criterium du Dauphine, Stage 6, Final Climb Le Collet d'Allevard

Joaquim Rodriguez

Elevation / Höhenmeter [m] : 961 m
Distance / Streckenlänge [Km] : 11.2 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1926 = 32 min 6 sec = 32:06
Weight rider / Gewicht Fahrer [kg] : 57 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.5 %
Average speed / mittlere Geschwindigkeit : 20.9 Km/h
Total weight / Gesamtgewicht : 65.0 kg

Power : 385.0 Watt
Power / kg : 6.7 Watt / kg

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

That's a VAM of 961 m / .5335 h = 1801

Very impressive for a 32-minute effort...

 

[biopass]

That's a VAM of 961 m / .5335 h = 1801

Very impressive for a 32-minute effort...

And funny looking by the same time with the way he constantly moves his upper body when climbing

 

[halamala]

Wiggins climbed 6.2 W/kg

Criterium du Dauphine, Stage 6, Final Climb Le Collet d'Allevard

Bradley Wiggins

Elevation / Höhenmeter [m] : 961 m
Distance / Streckenlänge [Km] : 11.2 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1980 = 33 min 0 sec = 33:00
Weight rider / Gewicht Fahrer [kg] : 72 kg [ Source: TeamSky.com ]
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.5 %
Average speed / mittlere Geschwindigkeit : 20.3 Km/h
Total weight / Gesamtgewicht : 80.0 kg

Power : 447.7 Watt
Power / kg : 6.2 Watt / kg

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

 

[Lanark]

Tomorrow they go to La Toussuire, they did that climb in the 2008 Dauphiné as well, and in the 2006 Tour of course. Would be interesting to compare some times.

 

[MrRoboto]

Joaquim Rodríguez using the giro to get in form to the Dauphiné? ^^

 

[Le breton]

Criterium du Dauphine, Stage 6, Final Climb Le Collet d'Allevard

Joaquim Rodriguez

Elevation / Höhenmeter [m] : 961 m
Distance / Streckenlänge [Km] : 11.2 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1926 = 32 min 6 sec = 32:06
Weight rider / Gewicht Fahrer [kg] : 57 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.5 %
Average speed / mittlere Geschwindigkeit : 20.9 Km/h
Total weight / Gesamtgewicht : 65.0 kg

Power : 385.0 Watt
Power / kg : 6.7 Watt / kg

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

Using my favorite programme, I get 379 watts, no problem there.

Where I have a difficulty is with the data themselves

Elevation / Höhenmeter [m] : 961 m
Distance / Streckenlänge [Km] : 11.2 Km

Where did you get those numbers?

Given A.S.O.'s lack of attention to such details I hope they are not your source.

According to salite.ch (I know they are not without fault and lack fine details)
the Collet d'Allevard includes a 10 km section with 860 meters uphill, between km 1 and km 11 on this profile
http://www.salite.ch/allevard.asp?M...7zibp&dx=485&dy=330&empriseW=970&empriseH=661

But if that profile is correct, it is impossible to get more than about 920 m altitude gain over 11.2 km on that climb.
Using the data from "ATLAS DES COLS" Alpes du Nord, the most altitude gain possible is just under 940 meters.

In the first case Rodriguez' power in watts/kg goes down to 6.4 and in the 2nd case to 6.52 watts/kg.

 

[halamala]

Where did you get those numbers?

Given A.S.O.'s lack of attention to such details I hope they are not your source..

Sorry, my source is ASO.

 

[Le breton]

Sorry, my source is ASO.

The profile shown is more detailed than I've been used to coming from ASO.
Maybe it's right. Don't know.
Thanks anyway.

 

[Alex Simmons/RST]

Haven't read whole thread. I note lots of calculations without taking wind conditions into account. Even slight head/tail winds (or drafting from leading vehicles) make quite a sizeable difference to the power estimates (or ascension rates for a given W/kg).

I plotted the variance in W/kg estimates for Alpe d'Huez given different wind conditions in this 2010 blog post here:

http://alex-cycle.blogspot.com/2010/07/ascent-rates-and-power-to-body-mass.html

 

[Ferminal]

The range would be between 947m and 961m. Take the bottom as either 461m (ASO) or 475m (Salite). I think the finish is most likely the 1422m given by ASO, as it finishes before it flattens out. ASO probably just started the climb a few hundred metres lower (hence the 461m). The ASO numbers look to be quite correct.

 

[Le breton]

Haven't read whole thread. I note lots of calculations without taking wind conditions into account. Even slight head/tail winds (or drafting from leading vehicles) make quite a sizeable difference to the power estimates (or ascension rates for a given W/kg).

I plotted the variance in W/kg estimates for Alpe d'Huez given different wind conditions in this 2010 blog post here:

http://alex-cycle.blogspot.com/2010/07/ascent-rates-and-power-to-body-mass.html

I have never felt wind in the bottom half of Alpe d'Huez. However, in the last km it can be a factor, unfavorable.

As for yesterday, 150 km North of the stage finish, wind was strong and instead of climbing La Faucille, I went for another climb (a dead end) in the woods where there was no wind whatsoever.

 

[halamala]

Re-calculation: Rodriguez climbed 6.6 W/kg, Wiggins 6.1 W/kg

The range would be between 947m and 961m. Take the bottom as either 461m (ASO) or 475m (Salite). I think the finish is most likely the 1422m given by ASO, as it finishes before it flattens out. ASO probably just started the climb a few hundred metres lower (hence the 461m). The ASO numbers look to be quite correct.

Re-calculation [Elevation 947 m]

Criterium du Dauphine, Stage 6, Final Climb Le Collet d'Allevard

Joaquim Rodriguez

Elevation / Höhenmeter [m] : 947 m
Distance / Streckenlänge [Km] : 11.2 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1926 = 32 min 6 sec = 32:06
Weight rider / Gewicht Fahrer [kg] : 57 kg
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.4 %
Average speed / mittlere Geschwindigkeit : 20.9 Km/h
Total weight / Gesamtgewicht : 65.0 kg

Power : 380.4 Watt
Power / kg : 6.6 Watt / kg

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


Bradley Wiggins

Elevation / Höhenmeter [m] : 947 m
Distance / Streckenlänge [Km] : 11.2 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 1980 = 33 min 0 sec = 33:00
Weight rider / Gewicht Fahrer [kg] : 72 kg [Source: TeamSky.com]
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 8.4 %
Average speed / mittlere Geschwindigkeit : 20.3 Km/h
Total weight / Gesamtgewicht : 80.0 kg

Power : 442.1 Watt
Power / kg : 6.1 Watt / kg

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

 

[Escarabajo]

Where is Halamala with those Tour de Suisse numbers?

 

[halamala]

Where is Halamala with those Tour de Suisse numbers?

You have to wait until Tuesday afternoon (GMT+0).

 

[Escarabajo]

You have to wait until Tuesday afternoon (GMT+0).

Ok.

Thanks.

I have been so busy lately.

 

[Alex Simmons/RST]

I have never felt wind in the bottom half of Alpe d'Huez. However, in the last km it can be a factor, unfavorable.

It does not take much wind. For instance we would barely feel a wind of 0.5 - 1m/s, yet even that can have a sizeable impact on the power estimate.

From ~ 1.6 m/s you can begin to feel wind on the face.

Suggest looking up the Beaufort Scale.

Even very light winds can have an impact.

Estimates need to have error bars or ranges shown. Not just for wind, but also for other assumptions (especially mass & gradient).

 

[python]

<snip>
Estimates need to have error bars or ranges shown. Not just for wind, but also for other assumptions (especially mass & gradient).

+11

i lost count how many times this has been stressed.

i believe some regular contributors realise this, most readers likely don't.

 

[acoggan]

It does not take much wind. For instance we would barely feel a wind of 0.5 - 1m/s, yet even that can have a sizeable impact on the power estimate.

It is also worth mentioning that most vane- or cup-type anemometers (by far the most common type, especially of those sold to consumers) can't measure wind speeds that are that low.

IOW, you could be standing at the side of the road taking measurements with one, record a value of zero, and yet the rider(s) would need to produce more (or less, depending on which way the wind is blowing) power than you calculate because of the wind.

 

[Chuffy]

+11 +/-15%

i lost count how many times this has been stressed.

i believe some regular contributors realise this, most readers likely don't.

Fixed for strict accuracy.

Keep up the good work chaps, fascinating stuff.

 

[keen_but_slow]

By way of control, Wiggins' SRM showed 476W for a 20 minute TT the other week in the UK. Very minor event (for him), no reason why he would treat it specially. No blood taken as far as I know. That puts him ~450w for an alpe d'huez ascent in isolation. See how he goes at the end of a stage in the middle of a GT. Bit of a breeze higher up past Huez village, but no wind lower down (however much I shout and scream for some cool air), so your man's estimates shouldn't be that far off.

However, as I've said before, it's relative performance 2nd day after the 2nd rest day when you need to watch with a cynical eye ..... he got a pasting off the astana boys in 2009.

 

[euanli]

It wasn't a minor event for him. Wiggins and Hutch have been in friendly competition for a while.

 

[Escarabajo]

It is also worth mentioning that most vane- or cup-type anemometers (by far the most common type, especially of those sold to consumers) can't measure wind speeds that are that low.

IOW, you could be standing at the side of the road taking measurements with one, record a value of zero, and yet the rider(s) would need to produce more (or less, depending on which way the wind is blowing) power than you calculate because of the wind.

Add to that the constant changes in kinetic energy which usually if not never is taken into account because we usually assume constant speed. The closest we get to the power numbers is when we do it by sections but even then you have to assume constant speed for that section and wind hitting in the same direction.

Now all this tells me that usually we underestimate the power values. I have always said that. The only thing I can do to approach the real numbers is to correlate against a rider that have published their power numbers (if well calibrated).

Now, to be honest there is no reason to get to the bottom of the exact number, at least not in my case, because I use it qualitatively in order to compare numbers of the past which have been calculated more or less with the same error.

Just wanted to add a comment.

 

[halamala]

Cunego climbed 5.7 W/kg

Tour de Suisse 2011, Stage 3, HC climb Grosse Scheidegg [last 13.0 Km]

Damiano Cunego

Elevation / Höhenmeter [m] : 981 m
Distance / Streckenlänge [Km] : 13.0 Km
Time in seconds / Fahrzeit in Sekunden [sec] : 2344 = 39 min 4 sec = 39:04
Weight rider / Gewicht Fahrer [kg] : 58 kg [Source: TeamLampre.it]
Weight bicycle, clothes etc. / Gewicht Fahrrad [kg] : 8 kg

Grade / mittlere Seigung : 7.5 %
Average speed / mittlere Geschwindigkeit : 19.9 Km/h
Total weight / Gesamtgewicht : 66.0 kg

Power : 330.9 Watt
Power / kg : 5.7 Watt / kg

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