Welcome to the Science of Sport, where we bring you the second, third, and fourth level of analysis you will not find anywhere else.

Be it doping in sport, hot topics like Caster Semenya or Oscar Pistorius, or the dehydration myth, we try to translate the science behind sports and sports performance.

Consider a donation if you like what you see here!


Did you know?
We published The Runner's Body in May 2009. With an average 4.4/5 stars on Amazon.com, it has been receiving positive reviews from runners and non-runners alike.

Available for the Kindle and also in the traditional paper back. It will make a great gift for the runners you know, and helps support our work here on The Science of Sport.



Wednesday, July 23, 2008

Tour update: The Alps

Tour de France Update: Will today be the decisive day?

Apologies for the absence in our Tour de France coverage. It's been a while since we last commented on the developments in France, and our last post dealt with the positive drugs test of one of the race's most exciting riders, Ricardo Ricco. We'll pick up on that theme again in another post (directly above this one), but first, some race action to comment on.

Overview of the Alps and a look ahead

It's been a great three days in the Alps (with the rest day in between), but it's today's stage that should be the biggest indicator so far to who is actually going to wear yellow in Paris on Sunday. Three HC (out of category) climbs, Col du Galibier, Col de la Croix de Fer, and the most famous of all, Alpe d'Huez, stand between the riders and the finish line in today's final mountain stage of the Tour.

And it's an incredibly tight bunch at the top - 4 riders are within one minute of the leader, Frank Schleck of Team CSC, who took the jersey on the ride up to Prato Nevoso. Denis Mechov of Rabaobank should also have been within one minute, but he amazingly lost time on the descent of the Bonnette yesterday and so finds himself 1:13 down.

Cadel Evans, who was the leader when the Tour started the final climb up to Prato Nevoso on Sunday looked much better on the Bonnette yesterday, but he'll only really be tested when attacks come. He was ruthlessly attacked on Sunday in Italy, with five or six guys taking turns to launch off the front. And it's been quite noticeable that Evans is always the last to respond to sudden changes in pace, and lacks the ability to accelerate. Alp d'Huez will therefore not be his favoured climb, because it does lend itself to shifts in rhythm and pace.

Schleck, Kohl, Sastre and Menchov will all have to attack today, because they know that a 53km time-trial on Saturday is going to see them lose some time. How much is difficult to say - a man in yellow, or riding for yellow, is worth a good 5% more, and so judging just how much time they require over Evans, the race's best time-triallist, is difficult to say.

Alp d'Huez - brief description

Alp d'Huez, which hosts the finish of today's stage, is one of the most famous climbs in world cycling, with its 21 hairpin bends (virages, or lacets) on the way to the top. It's an incredible spectacle for fans and makes for great theatre. In riding terms, for what my experience is worth, it's not quite as difficult as some of the other climbs, particularly in the Pyrenees. My recollection of it differs from the profile (at least, the one provided by a reader), because my recollection of riding it and seeing profiles is that it starts out very steep - the first three hairpins are a long way apart with some seriously steep roads between - 10 to 11% average. However, the middle section is much easier, where I recall the climb levelling off. Again, one profile doesn't suggest this, so I am perhaps recalling incorrectly, but I don't fully trust the profile...There is then a kick up to the incredibly steep part about 5km from the summit, which may be decisive in today's stage. I suspect that Evans will struggle early, and during this steep kick, but in the middle, I expect he'll control the race and maintain his losses.

Also, the presence of the hairpin bends offers something of a reprieve, because they are actually very gradual, almost flat. In the Pyrenees, the hairpin bends tend to be about twice as steep as the straight sections between them, and so are often the worst part as you strain to press through them. So while Alp d'Huez is a brutal climb, it's not the hardest of the race, but it's location and the preceding climbs will make it decisive today.

Stage prediction: Schleck to win, but narrowly

Enough of the descriptions, however. Today's stage should see some great racing. Team CSC are clearly the best team in the race. They've got three or four men who should start the final climb with Schleck and Sastre, whereas Rabobank and Lotto seem devoid of support riders for Menchov and Sastre.

Therefore, expect a fast tempo by CSC on the early climbs (behind the usual breakaway), a regrouping towards the bottom of the climb, and then attacks on the steep part, very early on Alp d'Huez. If you want a prediction, I'll say that Schleck gets away, but not by much. It's interesting that time gaps are always so small - no one rider is able to produce the physiology required to crack other riders and the days of one minute or more thanks to vicious attacks at the bottom of the climbs are long gone - is that a reflection on "reducing" drug use? I'd guess so...

As for Evans, I suspect that he'll probably eventually crack under the attacks, but that he'll limit his losses by riding hard on the middle, flatter sections, and probably lose at most 30 seconds. That might be enough to help him into yellow on Saturday.

We'll bring you that action as it happens!

Ross

5 Comments:

Seb said...

it then levels off to around 5 to 6% in the middle section

Noooo, no way. I've raced it, and there is no levelling in the middle. The bends are nearly flat, the beginning is flat, and the last 1500m are much easier. But there is no ramp in the climb below 8%. A steady 8 to 10% is all you get, with a few harder portions, and the bends leave you hardly time to drink a shot.

Just check the profile:
http://www.ulb.ac.be/di/ssd/ldoyen/profils/alpeduez.gif

L'Alpe is not that long, but it's a monster. And if the weather is hot and sunny, it's really hard.

Ross Tucker and Jonathan Dugas said...

Hi Seb

Interesting, I don't have the same profile as you. I recall that in 2005, a paper was published and presented at the American College of Sports Medicine analysing Lance Armstrong's power output during his 2004 Time-trial on Alp d'Huez, and the scientist who did it had to go to the Alp himself and measure gradients because the commonly reported profiles somehow miss things or misreport them. I recall from that paper that the middle part was much less steep, which agrees with my own perception having ridden the climb three times since 2005. It will be interesting to see power output data from the teams, after the stage, because that might shed some light. I'll try to find that paper where it was reported.

I certainly maintain that the big attacks will come at the bottom (first 3km) and then again at about 7km, with that middle period settling the race down, because of this. We'll see.

Ross

Ray said...

I found a different profile (http://www.salite.ch/huez1.asp) which shows some parts as level as 7%, which seems quite easy when you've been riding 10%+

-Ray

Andrew said...

This has been an exciting TdF so far, eh? I appreciate you guys lending your expertise to the race.

Would you guys explain the physiological differences between a good climber and a good time trialist? I can understand why sprinters generally aren't strong in climbs/TTs, but why is it rare for someone to excel in both climbs and TTs?

I understand that climbers need to be lightweight, but small folks would also be aerodynamic in a TT. Both disciplines require sustained high power output but I can't figure out the differentiating factors. Is there something mental/tactical about the pacing needed for TTs whereas climbing is more of a survival effort?

Anonymous said...

Not a bad call. Sastre won of course and Evans, or anyone else, couldn't go with him.

Sastre has 94 seconds on Evans. I've done a little calc based on their time differences in the Cholet trial (29.5 kms), which favoured Evans by about 80 seconds from what I can make of it.

So I figure Evans could have up to 150 seconds advantage in the longer Cerilly trial at 53kms -- which might give him about a minute to play with over Sastre. Barring disaters, none of the others can win I feel.

Paul