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Tuesday, July 19, 2011

Tour de France 2011: Rest day musings

Tour 2011:  Rest day, risk-taking and relative margins

The Tour is enjoying a rest day.  Call it the calm before the storm that awaits in the Alps, starting on Wednesday.  Most of my thoughts have been covered in my last two posts, first on the state of the race (and the sport, really) in the Plateau de Beille post and then yesterday, giving some context to the performances by looking at the biological passport and how it seems to have altered doping behaviour.

But, today being a rest day, it's a good chance to catch our breath and look ahead.  I'm absolutely snowed in with a research grant application due today, so I had time only to throw together some quick thoughts.

Anxiety among the GC contenders?


If you look at the current leader board, the name that jumps out instantly is Thomas Voeckler.  His presence there is only part of the story - the real plot is the apparent ease with which he marked all the attacks on the Plateau de Beille, controlling the race with aplomb, in the manner one might expect Contador and Schleck to do.  He didn't hang onto the jersey, he controlled it.

I'll get to Voeckler shortly, but in terms of "anxiety" (too strong a word, but let's go with it), the question is around the other GC contenders.

First, the Schlecks.  Currently in second (Frank) and fourth (Andy), they trail Voeckler by 1:49 and 2:15 respectively.  What attacking there was in the Pyrenees was primarily instigated by these two, as was the tempo on the early part of the climbs, with their Leopard-Trek team doing most of the work.  The source of any concern for them will surely be the relative ineffectiveness of both the tempo and their attacks.  The team effort at the front saw fully 30 men ride the first quarter of the climb together, and their attacks were marked sharply and neutralized.  Contador responded to all but one of them on the Plateau, and Voeckler was similarly responsive.  To date, only one attack by Frank Schleck has gained time (if we ignore the little sprint that got Andy two seconds the other day).

The Schlecks may well have more in the tank, and they'll need to find it, because front of their minds, alongside Voeckler, will be Cadel Evans, who is arguably the best time-trial rider in the Top 5.  He currently concedes only 17 seconds to Frank and is ahead of Andy by nine.  So the Schleck's thinking must surely be that if we could skip the Alps, and jump straight to the time-trial, they're not winning this Tour, even if they can beat Voeckler by 2 minutes!  So the onus is squarely on them to attack and to make an even bigger effort to a) drop Evans and b) trim Voeckler's lead to at most a minute before Saturday.  That's cause for some nervousness ahead of the Alps.

Then there is Evans.  Of the top 5, he may have the least to be concerned about in terms of the race situation.  His time-trial ability affords him the luxury of not having to attack, though there there is the 2:06 to Voeckler that might concern him.  But for him, the anxiety takes the form of doubt.  Will he be able to avoid even 10 bad minutes in the Alps, let alone a bad climb or day?  Those 10 bad minutes might cost him a minute, be it to Voeckler, the Schlecks, Contador.  And if that happens, it doesn't end Evan's Tour hopes, but they're under threat.  A bad day, two or three minutes, and his Tour hopes are over.  And so he'll climb knowing that attacks must come, from the Schlecks, as mentioned, and Contador, as we'll discuss next, and his question is whether he will be able to respond?

Contador next.  His hold over the Tour (and his streak of six consecutive Grand Tour wins) is slipping away, and the Alps are his only chance of setting up a win.  His gap of 4:00 to Voeckler is bad enough, but the 1:45 to Andy Schleck and 1:54 to Cadel Evans make his Alp performances rather desperate.  He must attack.  And if (or when) this happens, he might ultimately be the catalyst that decides this race.

Whether he can make up the necessary time remains to be seen.  His Pyrenean performances were unusually 'flat', and that has one of two explanations.  Either he is carrying fatigue over from the Giro, or his knee and other problems that affected him in week 1 were hampering him.  If it's the former (Giro fatigue), then expect Contador to lose more time and at best, respond to attacks in the Alps.  No gain, only maintenance,and more likely is that he'll get worse.  But if it's the knee, then the rest day, and the two easier days following it, may just see him regain some form.

Contador holds the key?

And with form may come a Contador attack.  If that happens, Contador may actually have the decisive say in where this year's final yellow jersey is going.  Up to now, we've seen attacks from the Schlecks, but they've done little to the other big 5 (we've added Sanchez!)  If Contador attacks, and if it's anything like a typical move, then he won't just sit up and allow the regrouping we saw in the Pyrenees - it'll be a prolonged attack, or repeated attacking, and the field will be split, if only for a short time.  That may be the platform that the Schlecks, Basso, or Evans need to finally break the race open.  The irony then is that it may be Contador who holds the key, even though his chances of winning the race overall need more than a few good rides from him.

Basso has climbed solidly, and even shown signs of aggression.  His time-trial abilities have always been questionable (he lost about 4 minutes to Cadel Evans in the recent Dauphine time-trial over much the same route as Saturday's TT), and so he's in the same situation as Contador - he must attack before we leave the Alps.  Whether he has that ability is a question, and I suspect at best, he'll be the beneficiary of others' aggression and rides strongly without making a decisive move.

Aggression vs conservatism, and the Alps to force the risk-taker's hand

There's been some great discussion in the previous two posts about the apparently cautious strategies to date, and suggestion that more aggression is needed.  I feel that the Alps will provide this aggression, a risk-taking style of riding that we didn't see in the Pyrenees.  The simple reason is that in the Alps, the strategy is going to be dictated by the approaching time-trial rather than the current GC standings, and as mentioned above, there are riders who absolutely must take risks.

The thing about strategy, and particularly in the Tour de France, is that it's like a game of poker with one crucial difference - the cards you have and the way you play them on one day has repercussions for the cards you'll have the next day!  A big effort one day - call it a large investment or spending of energy - will invariably be followed by a poorer day the next, so the key is to decide how to spread the investment most effectively.  This is pacing strategy on a grand scale, not the allocation of 'physiological resources' within an exercise bout, but over many repeated bouts.

And while I'm not going to go on about the doping issue, since that came across in the post on the weekend, a cleaner Tour would place a premium on those resources - they are not infinite.  They never were, but they're now far scarcer than before (call them a precious resource) and so conservatism will invariably rule.  And when you get that caution, then riders who ordinarily might be 1 to 2 minutes down as a result of perhaps those 3 to 4% differences in capacity, are able to survive, the beneficiaries of 'doubt' so to speak, and so this caution is also responsible for the expanded groups we've seen on the climbs so far.

Of course, it is possible to ride aggressively - take advantage of a "good day" and really go for it, with a long attack.  But the problem is again shown by the poker analogy - as in poker, you don't know what cards the other riders hold, and so you have to try to decide what's best for you, worst for them, without complete information!  You don't even know whether your cards will hold throughout the day, and so even on a single climb, a big attack 11km out could prove costly, because the ability to sustain the kind of super-high power outputs needed to accelerate away from a group and then maintain an advantage is limited to maybe 25 minutes.  Time it wrongly, and you'll be going backwards with 2 km to go and the result is a lost Tour.

But the Alps will force this risk-taking on the race, and that's why it should produce some fantastic racing!

Voeckler - the margins and the implications

Finally, there is Voeckler, perhaps the biggest story of the Tour.  I mentioned the other day that Voeckler's lead of 1:49 was large enough to keep him in yellow until the time-trial, unless he drops off the level we've seen.

That's because I don't believe that anyone in that big 7 can elevate performance by more than a few percent.  There's definitely some reserve there, make no mistake, but even a jump to what I consider a ceiling will see them chip away at his lead, not blow it out.  The only way Voeckler is not wearing yellow during the time-trial is if he cracks in the Alps.  If he continues with the form he showed in the Pyrenees, he's in yellow.

And to illustrate this, take a look at the following graph, which was drawn by the always insightful Alex Simmons (who sometimes posts on this site), and taken from the cyclingnews forum last week.  It shows the the predicted time on Alp d'Huez as a function of power output (in W/kg) and with different wind conditions.  The blue line shows the predicted times without any wind.


So for example, climbing at 6W/kg will produce a time of about 39:20.  The question to be asked around the 2011 Tour is how Voeckler might lose a 1:49 lead?  And bear in mind there are two mountain top finishes - the Galibier is longer, comes after a tough stage, finishes at a higher altitude, but it is less steep. Alp d'Huez is the final climb of the Tour.  Both have the capacity to change the Tour leaderboard, but let's look at what it will take.

So below is the same graph, with three additions:

  • First, the blue circle indicates the performance we'd expect if the power output was similar to what was predicted on Plateau de Beille.  There, it's been estimated that the top men averaged 5.7 W/kg for about 47 minutes.  The same on Alp d'Huez gives a time of 41:10.
  • The yellow indicates the equivalent to Luz Ardiden, where the average was 5.9 W/kg (an estimate, admittedly).  There, it predicts a 39:50.
  • The green box indicates that within this range of power outputs, a time gap of 1 minute would be created for every ± 0.2 W/kg difference.  In other words, if Voeckler were to ride at 5.8 W/kg (in line with what he's done so far), then his rivals would need two consecutive days of 6 W/kg in order to wipe out his 1:49 lead.  



So, a few scenarios:

  • If Voeckler can produce the same kind of performance as he did on Luz Ardiden, then he's going to ride Alp d'Huez in around 40 minutes.

    Next question:  how much faster can the others go?  6W/kg gives them a predicted Alp time of 39:20, and so they cut the lead by ± 40 seconds.  Maybe they'll find 6.1 W/kg, in which case they do a 38:50, and Voeckler's lead is cut to under one minute.  Per day, which may see a new yellow jersey by the Grenoble TT.

    Of course, there's a chance that they're already near the limit - perhaps 5.8 to 5.9 W/kg is the capacity.  In that case, Voeckler holds basically the entire lead and starts the time trial with 1:49
  • If Voeckler drops his level even slightly, but the others don't, then expect to see a time gap of 60 to 90 seconds on the climb.  5.6 W/kg vs 5.9 W/kg means just under two minutes on the climb.  One day like this and Voeckler's out of yellow
  • Obviously, if Voeckler cracks big time and rides at even 10% slower than he has so far, then he'll lose significant time, many minutes, and it'll be a race between the top men
Finally, remember that the race is not an individual time-trial or mountain climb. The group nature means that Schleck or Contador riding at say 6W/kg will not simply gain a minute into anyone riding at 5.8W/kg, because he'll just pull him up the hill. So what I described above for Voeckler, the one minute per 0.2 W/kg is only true if a gap is created and it becomes a race against the clock, so to speak.

Therefore, the ability of any of the Big 7 to create time gaps in the Alps takes more than just a higher power output.  It takes an initial attack where the power output will hit 700 to 800 W (11 to 12 W/kg) for a short time, followed by the ability to sustain that higher power output.  You'll often see an attack that splits the group, but then it gradually comes back together - that's because the attacker is able to lift the power output instantly, but not to sustain it, whereas those behind can gradually ramp up and pull themselves back up.

So Contador, again, may hold the key, because his normal attacks will split the group, and then if anyone has the ability to lift the tempo at the front, Contador may provide them with the chance to express what may be the small, but very real, differences between the potential champions and the top 10 riders.

Regardless, it'll be a huge showdown in the Alps, full of intrigue and drama, and with fully seven or eight role-players!

Enjoy the flat stage, and the first Alpine showdown!

Ross

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1 Comments:

Andy R said...

Wow great article! Don't forget that Contador is superb time triallist, I suspect that he'll have the edge over Evans in Grenoble.