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Saturday, July 23, 2011

Tour 2011: Alp d'Huez, leaving the mountains and onto the TT

Tour de France 2011: leaving the mountains and onto the TT

The Tour de France is now only one day away from finally answering every question posed of it, and its riders, almost three weeks ago.  A time-trial in Grenoble holds the final answer:  Schleck or Evans?

But much fell into place during the Alp stages - we now know that Contador wasn't quite up to the challenge this year (though the relative effects of the Giro and the knee problems are not known), we know that Andy Schleck carried good form into week 3, and we've seen Cadel Evans' strength and consistency, and has certainly had the least drama-filled Tour.  We also finally saw Thomas Voeckler pay for his great performances, but he certainly inspired along the way.

Aggression in the Alps

Yesterday's stage up the most famous climb in the race, Alp d'Huez produced some incredible racing.  If the Pyrenees were described by the word "conservative", then the Alps were the polar opposite.  Aggression was the feature, not only yesterday but all the way back to the foothills of the Alps where Contador ignited the race through his attacks on Cat-2 climbs.  Then on Thursday, it was Andy Schleck, launching with 60km to go, and finally, to bookend it all, Contador attacked even earlier, on the Col du Telegraphe and pulled Andy Schleck away from the chasers.

That brought a concerted effort from BMC at the front of the peloton on the Galibier.  At one point, Contador and Schleck had almost two minutes' advantage over Evans and Schleck, but BMC first held it, then slowly reeled it back, before Evans found himself, for the second day in a row, pulling the peloton up to an early break with a Schleck in it!  His effort closed the gap to around 30 seconds by the top, and on the very long 40km descent to the foot of Alp d'Huez the gap was removed.

So had you tuned in then to watch the final climb, it looked like just another day.  It had been anything but.  Meanwhile, Thomas Voeckler was doing a ride to admire, if not wonder about slightly - he tried to follow the Contador/Schleck break, but wasn't quite able to bridge.  And he hung to a tantalizing gap of around 30 seconds for a big part of the Galibier.  It went to 40 seconds, then he fought it back to around 20 seconds.  Then it went up, then it came down.  Voeckler the yo-yo was agonizingly close, and at times, less than 100m away from the group.  But he couldn't quite close it and within the final 4km of the climb, he finally cracked.

He was reeled in by the pressure from behind, and promptly dropped from that Evans group as well.   Perhaps, in hindsight, having failed to bridge, he might have waited for the chase group and been pulled back by them - but this is easy to say afterwards.  Fact is, Voeckler was inspirational.  While he managed to catch up on the descent, it seemed that barring a miracle, his yellow jersey tenure was over, but not without providing some of the race's great performances and highlights in the process.

Alp d'Huez: instant separation

Then on Alp d'Huez, the race exploded (I'd say "literally exploded" but that's what Paul Sherwen says, and fortunately, it's not quite true!).

And it's worth analyzing some of the performance times for different stages of the climb, because they show how Contador actually cracked about two thirds of the way up the climb, after an incredibly strong bottom third.

The historical context of the climb is equally interesting - the 41:21 climb of Sanchez was the fastest of the day - that's a return to the times we saw in the 1980s, when bicycles were considerably heavier.  However, I don't want to become too repetitive because the issue of performance analysis and characterizing the power of the climbs has been a regular feature of our Tour coverage this year.  So rather than spend minutes on it now, I have included that discussion in a separate "sub-post" section at the end of this post, for those who are interested in further debate.

If you want the summary though, the times yesterday do little to dissuade me of the view that performances are universally slower, and by a considerable amount.  Of course there are tactics, and there are varying conditions, but consider for example that all three regularly completed HC climbs in this Tour have been over three minutes slower in this Tour than were seen the 1990s and 2000s.  And not a single HC climb in the last two Tours have been done at anything close to 6.2 W/kg, let alone the 6.4 W/kg seen in years gone by.

And so the combination of performance times decreasing, the physiological implications of those performances and the bio-passport data suggest progress in the anti-doping fight - only more time will confirm or disprove that hypothesis.  For more, check the bottom of the post.

Contador's climb - hard, medium, crack pacing strategy

Contador's times were easiest to record, because once he attacked with 12.5 km to go, he was on camera most often.  I'll look at Roland's times relative to his, to give an indication of how the climb was structured by the two of them - it's very different.

So Contador rode the whole climb in 41:30, but it was set up with a first 3.8km of 11:24.  The next 5 km would take him 15:59 and then the final 5km 14:07.  His speeds thus dropped from 20.1 km/hour for the first 3.8 km, to 18.8 km/hour, before increasing to 21.3 km/h for the final segment (which includes some leveling off right at the summit)

Rolland, on the other hand, rode the first 3.8km in about 12:34 (he started 50 seconds ahead, then was caught and a gap of ± 15 seconds opened).  His next 5km was done in about 15:51 and the final 5km in 13:29.  His speeds per segment were 18.3 km/h, 18.9 km/h and then 22.2 km/h.

That is put into perspective when you consider the profile of the climb.  The first two kilometers are the steepest of the climb at over 10%, before it becomes more gradual, and then gets steeper at the top again.  Contador therefore attacked in the steepest part, and rode over a minute faster than Rolland over the first few kilometers.  He then slowed progressively even though the roads got less steep, and Rolland was able to hold him to 20 seconds before closing the gap and winning the stage.  This is further illustrated by the time gaps to the yellow jersey of Thomas Voeckler who held Contador to around 2:45 for much of the final 5km.

Contador therefore cracked, and that's partly the toll of stage and earlier aggression, both on the climb and those before it.  It's also because he probably rode well above capacity in those first 5km - I don't know the precise elevation of the climb by kilometer, but perhaps someone does and can estimate the power output per section based on the above splits?  The fact that Contador was faster on the steeper earlier slopes than from about 10km to 1km to go says much about how he ran out of reserves towards the top.  It was all Contador could do of course - he had to throw everything in and he did (to his credit).  In the end, just too much to ask.

Pacing strategy and the time-trial

And speaking of pacing strategy, perhaps that's a good point to leave the mountains and talk time-trial.  Today will see Cadel Evans try to overturn a gap of 57 seconds to Andy Schleck to win yellow.  I've spoken to a number of people about their projections and they range from a 2 minutes loss for Schleck to an equal performance!  Clearly, there will be some intrigue!

The two biggest problems with trying to guess the outcome of the final time-trial of the race are 1) the cumulative effect of fatigue is so difficult to predict, and 2) riders often don't ride them at 100% or with the same incentives at stake, because they don't need to.  Therefore, when you look back over the last few final time-trials, you find cases that support either position.

For example, in 2009, the final time-trial of the race was 41km (comparable length), and Cadel Evans beat Andy Schleck by 30 seconds.  But, that was a race where Evans began that time-trial well off the lead, whereas Schleck was in contention for the podium.  To highlight this even more, in last year's final TT, Evans finished 166th and over 5 minutes behind Andy Schleck!  Again, this was the time-trial where Schleck was fighting for the race win, Evans had little to gain and came off what was a relatively poor Tour and was riding with injury.

This year, that's quite different.  Evans has been strong and consistent - he's followed every attack, he's shown the strength to pull the peloton up two mountains in the last two days and he looks really solid for the win.  There's the yellow-jersey effect, of course, in that being in yellow supposedly adds the motivation necessary to find a better performance.  And while that's true, I don't believe it's a competitive advantage in a race like this.  Consider Cadel Evans - he has been trying to win the Tour for years and has come close on a few occasions.  Is there more motivation than that of a rider who knows his chance is 60 minutes of effort away?  I've always found it quite presumptuous to try to guess at people's motivation anyway.

The next issue is fatigue - Andy Schleck has had two enormous days in the Alps - a 60km break and then yesterday's efforts.  Cadel Evans hasn't exactly had it either though - he did all the work on the Galibier on Thursday and a great deal more yesterday.  But his allocation of effort has been more controlled and maybe a slight edge here.  Again though, it's impossible to guess at recovery and even effort allocation unless it's quantified, so this doesn't really help.

Pacing strategy is another interesting one.  When you're talking about an hour of riding and 53 seconds advantage, then small 1% differences as a result of pacing can be telling.  Going last is a slight advantage in that regard, because you know what the targets are.  And Schleck may be able to pace himself off Evans.  However, that's pretty meaningless if Evans is 2 minutes faster - all that will happen is that Schleck will be "pulled" too fast over the first half, and pay in the second.  So it will be fascinating to see how the relative gaps between the two unfold and how they structure their effort.

All in all, it should be a fantastic day.  We'll see what it throws up in terms of analysis and bring you the final yellow jersey tomorrow!  Thanks again for reading and discussion!  One day to go!  (and I won't lie, as enthralling as it's been I feel the need for holiday!  The Tour de France really is grueling!)


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The historical overview of the climb

In terms of the historical context of the 2011 performances, the overall time for Contador was 41:30.  Sammy Sanchez was the fastest of the day in 41:21, while Pierre Rolland, first to summit, did it in 41:52 because he started the climb with a 51 second lead (bear in mind small errors in timing off the TV - I'll watch it again and correct small errors later).  

It does not escape notice that the times were comparable to what we saw in the 1980s.  In the 90s and 2000s, sub-39 minute performances were expected, after Gianni Bugno and Miguel Indurain had been the first to break 40 minutes in 1991.  In fact, since 1994, seven of eight climbs have been done in under 39 minutes, let alone 40 minutes.  

Carlos Sastre in 2008 rode a 39:30, a sign of the passport, perhaps, and this is the first time (unless I'm missing something) that the fastest ascent of the climb has been outside 40 minutes.  And it wasn't just slightly outside - Sanchez did 41:21.  And many have commented that this fails to account for the earlier climb and tactics. True, but the size of the effect is too large to be dismissed.  The earlier efforts on the Galibier (which were not as massive as many think) might account for some of the difference, but this climb was over four minutes slower than Pantani's record, and 3:30 behind the times of 1995, 1997 and 2001.

Implications for power output

In terms of the implications for power output, below is the graph that I showed the other day as well, courtesy Alex Simmons.  It shows the expected climb time for different power outputs and different wind speeds.  On the note of wind, I have watched the climb three times now and there seems to have been a breeze in the trees, but the flags on camper vans and poles on the climb show very little wind, so I think the effect was minimal, but to give the benefit of the doubt, assume a headwind.  

Without wind, the climb was done at an estimated power output of 5.65 W/kg.  A headwind would push it up towards 6 W/kg.  At this point, it's worth saying that Chris Anke Sorensen (who we've been following all Tour) rode Alp d'Huez at 5.3 W/kg, and finished the climb in 47:10.  So just over five minutes off.  Within the relatively linear region of this graph, those 5 minutes are worth about 0.7 W/kg, so that puts the top climbers at ± 6 to 6.1 W/kg.  An alternative method is to take the Sorensen performance (47:10 and 5.3W/kg) an estimate the headwind and then derive the power output for the faster time of 41:30.  Turns out that it it predicts a headwind close to the yellow line shown above, and so the race leaders are climbing at an estimated range of 6.0 to 6.1 W/kg.  And that's a highest case scenario, I suspect it to be lower.

This is exactly what I'd expect of this level of rider at their maximal efforts at the end of a three-week Tour, as seen today, and as has been seen the entire Tour long.  To repeat a common observation in the Tour - this is much, much lower than we used to see in the 90s and 2000s, where climbs over 6.2 W/kg and higher were common place (for some of the data, see this post) and the lack of those performances now is conspicuous.

Of course, Alp d'Huez has rarely been done after such aggressive riding on the preceding climb.  Then again, it's rarely been done after only 93 km of riding either - today's stage was short, the total riding time "only" 105 km and took 3:13:25. 

And I readily acknowledge that any one climb in isolation paints a picture of nothing.  But I'd point out that this year, there have been three HC climbs that are regularly done in the Tour - Luz Ardiden, Plateau de Beille and Alp d'Huez.  Every one of them has been more than 3 minutes slower than the record times for those climbs, all of which were set in the EPO and blood doping era of the 90s and 2000s.  The same was true last year, incidentally - not once was an HC climb done at more than 6W/kg, whereas that was common in the 90s and 2000s - 6.4 W/kg was the average back then.  Even when you correct for tactics and weather, the number and magnitude of those differences is compelling.

The dividing line, I believe, comes in 2008, when the biological passport was introduced (and please read this for the context).  And now, as the Tour rolls out of the mountains again, it has once again suggested to me that a) performances of greater than 6W/kg (let alone the 6.2 to 6.7W/kg we used to see) are not credible and that b) the doping problem, while no doubt present, is coming back under control thanks to the stringent testing.  Obviously, this is still a hypothesis - let's get thirty or forty climbs that are slower, not the five or six in the last two years.  But so far, the data support the hypothesis, and only time will tell if it's true.