Power Data Estimates for the climbing stages

[Le breton]

For comparison with similar length effort
http://www.chronoswatts.com/en/watts/25/

[Red Rick]

Seems like an ok number. Though commentators made mention of rough road surface especially on the insides of the curves. Also, the pace set by the peloton wasnt huge in the first part of the climb, so I think they could've gone a bit faster.

[vedrafjord]

New paper for everyone to read (12 pages): https://drive.google.com/file/d/0B9BaZuAbl3tRSXg0SHdXalFlNVk/view

Estimating climbing performances of professional cyclists: a larger dataset

@ammattipyoraily & @thomaswire

Introduction
The initial work done by @ammattipyoraily and @veloclinic (Dr. Mike Puchowicz) [1] focused on the estimation of the power developed by a cyclist during a climb, either being in competition or in training situation. This first “insight” into the data gathering of well-known power estimation through the use of two different models, Doctor’s Ferrari Formula (DrF) [2] and J.Martin et al. equation [3], over 250 climbs.

Starting from this significant basis and following a relatively similar method, the work presented in here considers a grand total of 1252 climbs of sub-parts of climbs, for which the two models pre-cited are applied. We attempt to verify the applicability of such models, their limits and why, if so, they fail.

I haven't read this yet but it looks interesting so far.

[el_giles]

https://cyclingtips.com/2017/01/by-the-numbers-just-how-hard-were-the-uphill-finishes-at-the-2017-tour-down-under/

[meat puppet]

Fast riding yesterday. Very fast: "Nairo Quintana on Terminillo: ∼6.1 w/kg. Richie Porte on Couillole: ∼6.3 w/kg. Both efforts around 41 minutes."

Estimates courtesy of https://mobile.twitter.com/faustocoppi60 who frequently makes such calculations. Porte's Numbers are close to froome PSM and according to the author would warrant a top 10 all time alpe de huez, ie similar to virenque.

[Netserk]

With Ferrari's formula, Porte was ~6.1 W/kg (and Quintana a bit below that)

[meat puppet]

Still quite impressive, thanks! Did you calculate it yourself?

[Netserk]

Yes, with vetooo's numbers.

Nairo:

Source: https://twitter.com/ammattipyoraily/status/840641324403556353

Porte:

Source: https://twitter.com/ammattipyoraily/status/840634462073425922

That is with Ferrari's formula, I'm uncertain if (and how much) it underestimates the performances on such climbs.

[Red Rick]

I saw earlier estimations by ammattipyoraily estimating Porte at 5.7 That seems low, though ~ 6.1 seems quite high. The climb was very well paced though. They're good numbers though.

[Red Rick]

Any Col de Peille data?

[Mayomaniac]

Any Col de Peille data?

http://www.climbing-records.com/2017/03/another-contador-show-in-paris-nice.html

Cote de Peille
2017:6,6 km@7,0%---15:42---average speed 25.22 km/h(Alberto Contador)
---16:12---average speed 24.44 km/h(Sergio Henao)
2016:6,6 km@7,0%---16:00---average speed 24.75 km/h(Alberto Contador)-Strava
---17:00---average speed 23.29 km/h(30 riders peloton)-Strava

[Alex Simmons/RST]

Yes, with vetooo's numbers.

Nairo:

Source: https://twitter.com/ammattipyoraily/status/840641324403556353

A 58kg rider + 8kg bike+kit I get 6.4W/kg with zero wind Crr 0.004 and CdA 0.32m^2
6.3W/kg if I drop CdA to 0.29m^2

[Alex Simmons/RST]

VAM and W/kg for a rider of Quintana's weight, in no wind conditions on smooth road:

[Netserk]

I know it's higher for lighter riders, but when it's used as a measuring stick, I think it makes better sense to use a standardized weight (like DrF).

[Alex Simmons/RST]

I know it's higher for lighter riders, but when it's used as a measuring stick, I think it makes better sense to use a standardized weight (like DrF).

That makes no sense if you are seeking to compare physiological performance with the same W/kg measuring stick. If not, then one stick has different increments than other.

[Le breton]

Yes, with vetooo's numbers.
....
Porte:

Source: https://twitter.com/ammattipyoraily/status/840634462073425922

That is with Ferrari's formula, I'm uncertain if (and how much) it underestimates the performances on such climbs.

The figures given here are at odds with figures announced by ASO for the col de Couillole
Summit at 1678 m
The 15.7 km include a first km at 1.3 or 1.4% and that should be corrected for (depending where the time is measured from, if it's from km 0)
For 15.7 km the alt. difference is 1678 - 550 = 1128 m
For the last 14.7 km, it is 1678 - 563 = 1115 m
Without further precisions from Vetoo it's hard to conclude on <W/kg>

[Netserk]

I know it's higher for lighter riders, but when it's used as a measuring stick, I think it makes better sense to use a standardized weight (like DrF).

That makes no sense if you are seeking to compare physiological performance with the same W/kg measuring stick. If not, then one stick has different increments than other.

When wanting to compare different riders on different climbs, making their performances more comparable is important, at least it is for me.

Even if it requires a lower W/kg, I think it's more impressive for an 80kg rider to climb Alpe d'Huez in 40' than it is for a 60kg rider.

I get why some prefer an as precise actual W/kg as possible, but I just want to know who is the better climber/who can climb the fastest.

[Alex Simmons/RST]

I know it's higher for lighter riders, but when it's used as a measuring stick, I think it makes better sense to use a standardized weight (like DrF).

That makes no sense if you are seeking to compare physiological performance with the same W/kg measuring stick. If not, then one stick has different increments than other.

When wanting to compare different riders on different climbs, making their performances more comparable is important, at least it is for me.

Even if it requires a lower W/kg, I think it's more impressive for an 80kg rider to climb Alpe d'Huez in 40' than it is for a 60kg rider.

I get why some prefer an as precise actual W/kg as possible, but I just want to know who is the better climber/who can climb the fastest.

The better climber is the one who climbs fastest. You need no more information than that.

If you convert each rider's ascent rate into W/kg for a "normalised" 70kg rider with a fixed set of assumptions then all that happens is the faster rider has a higher "normalised" W/kg value, which tells you precisely nothing more than simply knowing the ascent rate. The ranking order for ascent rate will be exactly the same as for W/kg.

[Netserk]

So how do you compare different riders *on different climbs* if not by using a normalized W/kg?

[Alex Simmons/RST]

So how do you compare different riders *on different climbs* if not by using a normalized W/kg?

Not sure why you would in the first place since different climbs are, well, different. Compare the same climb and where possible understand what environmental conditions where if not performed on the same day.