Thursday, June 13, 2013

l'Alpe d'Huez. Again. Top 200

Some charts for fun. Pub chat, no more, no less.

Published on this Finnish forum are the top 200 ascent times for the Alpe d'Huez climb, often used in the Tour de France. I haven't been able to clarify how the times were established, nor if the same start and finish timing points were used. Official timing of the ascent started sometime in the 1990s but different timing points were used from 2001 onwards, so I cannot say with any confidence if we are comparing apples with apples. There are plenty on forums that definitely dispute Pantani's quoted climbing times (and that they should be somewhat slower than shown here, although still fast).

It's possible they reviewed footage to normalise these things, but in any case, nice work on collating the data, I'd say thanks personally but I don't speak or read/write Finnish. If any reader does, perhaps they can pass on my thanks.

Indeed racing context is also needed, e.g. Was it a long stage? Many previous cols? Attacking for the win or defending the maillot jaune? Conditions/weather/wind? Of course in 2004 the ascent was used for an individual time trial, not as the final climb of an alpine road race stage.

And yes, it's full of dopers and naturally covers the glory days when EPO, blood transfusions and other supporting cocktails were, sadly, the norm. Not that these things still don't happen, just seemingly not with the same outrageous impact on raw performance as before, at least not for the top of Pro Tour, but who knows about lower level riders trying to make the grade? Doping is still prevalent, and while the outrageous performance days may be suspended for now, the consequences are still just as insidious - shady characters and corruption, legitimate riders missing out on contracts and racing opportunities, people losing jobs, sponsors leaving, races and race results skewed and screwed, disillusioned fans. Long term health impacts. The list goes on.

As for conversion of ascent times to power to weight ratios, something that's been gaining in popularity lately with talk of mutants and the like as well as regular guesstimates published in online forums, well I cover that in this July 2010 post.

For reference though, using the methodology outlined in that post, the fastest time quoted in this list (whether or not accurate), would equate to a power to weight ratio of ~6.5W/kg +/- 0.4W/kg. Certainly not the nonsense level 7.2+ W/kg (or even 8W/kg) quoted by some.

In summary, just plot the ascent times and map the trends for individual climbs. Converting to a W/kg guesstimate may provide a way to make comparisons between climbs, but such estimates should be plotted with error bars, because there are too many unknowns in key assumptions and estimations are subject to methodological error. Converting actual performances to plot a wattage for a standard rider of 70kg makes even less sense, since W/kg is already normalising such estimates.

So here are two charts I whipped up from that Finnish forum data.

The first plots the fastest five riders each year. Click on it to see a larger version:


The next is a frequency distribution of the top 200 times for the years l'Alpe was raced.


What this means is that of the fastest 200 times recorded, 16 of them were in 1994, and so on. Quite clearly something changed between 1989 and 1991. One could speculate about other changes since then. Use of EPO, introduction of tests and of course doping detection avoidance measures, better tests, move back to blood transfusions as dominant in competition doping method and so on.

And a new chart, this one plotting the combined average speed of the top 5 riders (except for the first three years of data where there were fewer than 5 riders in the list for each of those years).


So, there you have it. enjoy the pub chat. And if you want to know how you compare, perhaps this other post about mere mortals might give you some beer for thought.

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