Tour de France: Luz Ardiden analysis and thoughts

Analysis of Luz Ardiden: ± 5.9W/kg and thoughts

It's a day late, for which I apologize (grant proposals due at work!), but hopefully better late than never, some analysis of the first big mountains of the 2011 Tour de France.

The race's first foray into the Pyrenees went some of the way towards 'cleaning up' the top page of the overall GC, but also left many questions unanswered, and introduced more than a few new ones!

Obviously, with three more mountain-top finishes and a time-trial to go in this year's race, this was never going to be the race's decisive day, but given the profile and the stakes after a tough first 11 stages, much was expected.  At the very least, yellow was expected to change shoulders, but even that did not happen as Voeckler produced a brave, inspired ride on Bastille day.

In the end, the stage is tricky to analyze and interpret, because at times, it was done quite conservatively.  The fireworks that were expected never really came, at least until about 4 km to go, when the first real testing moves came from Andy and Frank Schleck.

The pace of the lead group - the time gaps tell the story

The rhythm and intensity of the climb is best judged by looking at the time gaps between Sammy Sanchez, the eventual stage winner, and the peloton.  Jeremy Roy and Geraint Thomas began the climb with a lead of just over three minutes, while Sammy Sanchez and Vandendert had left the peloton and began the climb with a 20 second advantage.

The 3 minute lead was cut to 1:43 with 10km to go, and it seemed that the race would come together before long.  Sanchez and Vandendert were however edging ahead of the peloton, and when they caught Thomas and Roy at 8km to go, the gap was 44 seconds, meaning that Sanchez and Vandendert had grown their advantage on the yellow jersey group by a further 24 seconds over the first 5km of the climb.  At that stage, there were around 20 riders in the yellow jersey group (there had been 30 a full 3 km into the climb), which itself tells a story.

Meanwhile, back in the peloton, Basso and Sylvester Szmyd of Liquigas had gone to the front with about 10km to the summit.   Their presence may have nudged the pace up very slightly, but it did little to erode Sanchez's lead.  It dropped to 40 seconds with 7.5km to go.  The Liquigas drive was also the impetus behind thinning the lead group slightly  - it had been cut to 18 men with about 5 km to go, an extremely large group so late in the climb.  One of those to find the pace slightly too hard was Chris Anke Sorensen.  Immediately after the stage,  I was very eager to see his power output data because that would confirm the initial impression that the pace at the front of the race was solid without being exceptional.  More on that below...

But over this period, from 8km to 4km to go, the peloton actually slowed down.  Sanchez's lead grew from 40 seconds to one minute, then even more, and with 4km to go, the gap had grown to 1:20.  That means that Sanchez and Vandendert covered a 3.5km stretch 36 seconds faster than the big group chasing from behind.  It was quite clear that the tempo at the front had dropped.  And as well as Sanchez and Vandendert climbed, and as pedigreed a performer as Sanchez is, their climbing performances relative to those of the GC riders reveal that for all the talk and hype about the "brutal effort on the front", the top riders were not throwing every weapon at the climb.  When that finally happened, it was dramatic, and a 1:15 lead would be cut to only 30 seconds within about 2km, around 25 seconds per kilometer (and even more for Frank Schleck).  But on average, the climb today was a shade below the level we may see in future climbs.

Schleck attacks and the race hots up

The attacks, as mentioned, came in the final 4km, when the Schlecks did the expected and alternated going off the front.  The elite group was now cut to only eight men.  The fast-slow tempo with the attacks allowed others to rejoin, and by 2.6km to go, the gap to Sanchez had grown back up to 1:14.  Then Schleck made the decisive attack, and was able to go clear.  This was the catalyst to suddenly reduce the lead - it fell rapidly and with 500m to go, and Schleck had basically bridged the gap to Sanchez.  Sanchez responded, sprinting away to take the stage win, but Schleck had effectively knocked away a 1:20 second lead over 2.5 km.  The rest of the field were only 20 seconds back.

That field did NOT include, most notably,  Alberto Contador.  He lost 13 seconds to the main peloton, apparently all in the final two kilometers.  It doesn't augur well for Contador, because this was not an all-out effort by his biggest rivals.  Their efforts were hard, certainly, and it would be naive to think they had too much more, but the intensity could have been lifted slightly, and that suggests that unless Contador can recover remarkably well, he's in for a very tough few days, first on Saturday and then in the Alps.

A look at the power output values from yesterday will confirm this...

The power output analysis - under 6 W/kg, even at the front

First, take a look at the direct measurement (always the best) of power in Chris Anke Sorensen.  As mentioned, Sorensen stayed with the front of the race for the first 5km on the climb to Luz Ardiden.  He then dropped off soon after Liquigas went to the front.  His power output values, especially for the first 5km, would tell us exactly what kind of power output the lead riders were producing.

Very important point that I must make here - after Sorensen fell off the lead group, the pace of the Big 5 (and Voeckler and co) did not actually increase.  If anything, it slowed, as judged by Sanchez (who himself may have been slowing, remember).  So when you look at Sorensen, you're seeing a measure of the higher range of power outputs recorded on the climb, with the exception of the attacks that came later.

So here is Sorensen on Luz Ardiden (click to enlarge):

The key points:

• The first 5km, when Sorensen rides with Contador, Schleck and co, the power output in the front is ± 5.8 W/kg (376 W)
• Sorensen drifts off the back soon after, and completes the stage (final 8km) at 5W/kg
• His heart rate reaches 172 bpm.  You may recall that on the climb of Super-Besse last Saturday, he attacked on the final climb, having ridden the first 6 min at 6.4 W/kg, and his heart rate there reached 176 bpm.  So this was pretty close to a maximum effort.
• Once he dropped off the lead group, and settled down to the 5W/kg, his heart rate dropped to around 160 bpm, which is approximately 90% of maximum (I think it's safe to say his max is 176 to 180 bpm)

Frank Schleck's power output

Unlike Sorensen, none of the big GC contenders provide their power output data, but it's still possible to estimate power output knowing the time taken, the gradient and the distance.  This has been done (courtesy halamala over on the cyclingnewsforum), and the calculation is below:

Change in elevation: 979 m
Distance: 13.3 km
Time: 37:21
Weight rider: 67 kg
Total weight: 75.0 kg
Weight bicycle, clothes etc: 8 kg
Grade: 7.4 %
Average speed: 21.3 Km/h

Calculated power output = 394.6 W, or 5.9 Watt / kg

The same calculation over the final 10km, incidentally (where it's steeper, and where more of the climb includes Schleck's attack), produced an estimation of 396 W or 5.9 W/kg.  That is, basically the same.

Implications and testing the estimation

Of course, there is always error in these calculations, and situations where the actual power output will differ from what is estimated.  Wind and drafting factors are particularly important.  However, the data from 2011, courtesy Sorensen, give some real support to the accuracy of the calculations for Schleck.  Remember, Sorensen was riding at 5.8 W/kg to stay in the group for 5km.  Once he drifted backwards, the overall pace was probably slightly slower, until the attacks (distance of about 4km), when it picked up again.  So to estimate that Frank Schleck rode it at 5.9 W/kg over the entire climb seems reasonable to me.  If anything, it's too high.  It would be similar to Sanchez and Vandendert, and their subsequent performances will be interesting to see.

And again, part of the discrepancy might be explained by people saying that the race tactics were in play, that the situation was different, and that Frank Schleck and the leaders were not riding as hard as possible.  And sure, this may be true.  But if you think that can bridge the 10% gap between the likes of the 2003 performances and what happened in 2011, well, I find this optimistic. 

How much faster can the top men ride?  An increase of even 0.1 to 0.2 W/kg, which would project to a sustained power output of 6 - 6.1 W/kg might be expected to give a rider an additional 3 to 4 seconds per km, and they would cover the final 10km of a climb around 40 seconds faster than we saw today.   

For comparison's sake, when Lance Armstrong rode up to Luz Ardiden on the way to winning the 2003 Tour (the famous stage with the fall), his time for the final 10km was 27:08, a full 2:02 FASTER than Frank Schleck yesterday (again, thanks to halamala for the numbers).  The estimated power output for Armstrong then was 458 W, or 6.4 W/kg.

Where all this leaves us is with a couple of realizations:

1. The big shake-up is yet to happen.  To repeat, I don't think we're going to see massive increases in the power outputs from Luz Ardiden, but I do expect that the climb to Plateau de Beille and Alp d'Huez, for example, which are of similar length (37 to 42 minutes) will be climbed slightly faster.  Look for 6-6.1 W/kg on those slopes, and if that seems a trivial increase, it's enough to create gaps of five to ten seconds per kilometer compared to a guy riding 5.8-5.9 W/kg.  So the big effort still awaits.
   
2. All of this further confirms, to me anyway, that there is a "limit" to how much power a rider can produce going up a hill.  I've given the theoretical argument why this is the case before, and I estimate that around 6 to 6.2W/kg on these long climbs is the ceiling for normal performance.  But now, as we get more and more data, we're seeing the same thing emerge over and over - guys just do not ride these HC climbs to finish stages at 6.3, 6.4 W/kg or higher. 
   
   This is obviously a topic worthy of much more discussion, but that is for the gap between the mountains, when I'll look at it in more detail.

Right now, attention turns to the big stage on Saturday, which finishes on the Plateau de Beille.  As I said right at the outset of this post, there are some unanswered questions and some new questions from Luz Ardiden.  Contador's ability on the climbs is probably the big one - was his bad day a carry-over from the first week, in which case one extra day might have allowed him more recovery and he'll return to better form come Saturday?  Or was his performance the carry-over from the Giro, in which case things will only get worse?

One thing is for sure - if his form is off by even 5% thanks to the Giro, then the Plateau de Beille will expose it more than Luz Ardiden will, because the tempo at the front is likely to be harder (only slightly, but it counts!), and the attacks likely to come slightly earlier.  But don't expect big, decisive moves at 13km to go - those days are gone, along with the days of 6.5 W/kg climbing performances.

The other big question is how do Evans and Basso compete against the alternating attacks by the Schlecks?  Their tactic seems reasonably certain, and it's to go one and then the other, until eventually one move sticks.  Basso and Evans have never really been known for their ability to accelerate on the climbs, as good as they are in the mountains.  And so Contador's apparent lull in form does threaten to make the race a Schleck affair, because Contador was the one rider who could counter-attack.  It'll be interesting to see if the Schlecks just continue to chip out 30 seconds advantages on each stage, up to the time-trial when the race will be decided.

And Voeckler?  Great effort to keep yellow, but will it cost him on the second mountain-top finish?  Only time will tell!

Enjoy the racing!

Ross

P.S.  One last word on power - Chris Anke Sorensen's power output data is available for all three climbs in yesterday's stage, and you can see it here.   

Just to summarize:

La Horquette d'Ancizan, 9.9km at a power output of 338 W or 5.2 W/kg

Col du Tourmalet, 17.1 km at a power output of 349 W, or 5.4 W/kg

Luz Arideden:  5km at 376 W (5.8 W/kg) and 8 km at 325 W (5 W/kg)

And finally, here is the climb of the Plateau de Beille, to set the scene for tomorrow's finish:

Enter the Pyrenees

Tour de France: Today's climbs and the big GC shake-up

Today sees the first of the big encounters that will decide the Tour de France.  For the next 10 days, the Pyrenees and the Alps will loom large before the GC riders still remaining in this year's Tour de France.

There are four mountain top finishes in the the next ten days of racing, all of them atop the "out-of-category" climbs that are the longest and most challenging in the Tour.  The first comes today - Luz Ardiden.  This is the climb where Lance Armstrong famously won the 2003 Tour de France after falling when a spectator's bag hooked his handlebars.

It's a 13.3 km climb, at an average gradient of 7.4%, rising up from 741m to 1,715m at the finish.  The peloton will encounter tougher climbs than this in the course of the Tour.  For example, the Plateau de Beille which is the finishing climb on Saturday is longer (15.8 km) and steeper at 7.9%.  And from personal experience, if it's warm, that climb is doubly brutal because my recollection of it is that there's little tree-cover and most of the roads are south-facing.

Today's stage: Profile and finishing climb

But back to today.  Luz Ardiden comes at the end of a difficult day.  The first exposure to the high mountains is always challenging, because as we have seen, the main GC riders have been relatively sheltered in the peloton, and tend to ride with relatively low cadences, in big gears.  Today, that changes, and the legs must adapt to pushing the smaller gears, albeit on steep climbs.  This year's Tour has already been challenging - we had the teaser of Saturday's stage to Super Besse, for example, and so it hasn't exactly been pancake flat so far.

But, today are the real mountains.  The stage profile is shown below - it comprises a Category 1 climb with 80km to ride (9.9 km at 7.5%), and then the famous Col du Tormalet (17.1km at 7.3% - about the same gradient as the finishing climb, but around 4 km longer) at around 50km to go.  From the summit, it's down to Luz St Saveur where the final pull to the finish line begins, and where the racing will really hot up.

The slopes of the final climb are shown in a bit more detail below (click to enlarge).  It's always difficult to know exactly where a climb starts and ends, and the profile below has the climb a shade over 14.5km compared to the official listing of 13.3km, but work backwards from the finish and you get a rough idea. The Tour climb is probably measured from about 1.5km on the profile below.

There's nothing absolutely terrifying about any given section of the climb, no section that kicks up to 12%.  It's just a steady, hard climb at 8 to 10% pretty much the whole way.  But the series of kilometers in the middle, about halfway up the climb are probably where the biggest attacks may come.  That section is about 6km long, and at an average grade of 8.5%.

The first few kilometers "ease" the peloton into it, and here is where the support for team leaders will become evident.  The likes of Chris Anke Sorensen will appear at the front of the peloton to keep the intensity hard for their GC contenders.  We've seen from previous years that the intensity at the base of the climb will probably be at its highest - last year, for example, Sorensen rode at 6.6W/kg for the first 11:14 of the Col du Tormalet, and the intensity for the leaders dropped after his departure, as the overall power output was probably around 5.9 to 6W/kg on that climb.

That's with the exception of the attacks, of course, where the power output will jump to 10 W/kg or higher for the 30 seconds where a rider shoots off the front.

And the attacks are really the big question of the Stage today.

Physiological poker: Who has what?

There are a number of interesting questions around the racing strategy in today's stage.  Apart from the more obvious tactical issue of whether Contador (and to a lesser extent Robert Gesink) can attack in order to make up time lost as a result of falls in week 1, there is the ever-present issue of Contador's form against that of Evans and the Schleck brothers.

They're clearly following very different season trajectories, particularly Andy Schleck who has been very quiet all year, basically because he is building up to these 10 days.  Contador, on the other hand, has been prolific and won the Giro and now has the challenge, as we've mentioned, of maintaining form through another three-week race.

So will he attack?  Physiologically, it's interesting and almost the equivalent of game theory, because neither party knows what 'cards' the other is holding.  The simple truth is that Contador must make up time on the Schlecks and Evans (particularly Evans because of his better time-trial ability).  However, the choice for Contador is WHEN to attempt it?

This is going to sound obvious, but it has complex implications - his best chance is to attack when he is strongest and the rivals are at their relative weakest.  There are thus four different scenarios or "degrees of freedom" in that picture - Contador may be strongest now, and may struggle in the third week of the Tour because of the Giro effect. Then again, he may have detrained after the Giro and is now building fitness and will be strongest at the end.  All depends on his training in the month between the Giro and the Tour.

Similarly, for Evans and Schleck, the question is, are they building to an even stronger performance in the final week as a result of coming into the race "underdone"?  If so, then Contador's best opportunity may be in the Pyrenees, because as they strengthen (and he presumably weakens), it will become progressively more difficult.

So that's the big question on everyone's minds - how do the big four or five protagonists approach this stage (and Saturday's) given the stakes, the challenges that lie ahead, and also the situation that has been forced upon them by previous stages?

With it being Bastille day in France, expect a big French showing, in an early breakaway, but expect that break to have been brought back to a few minutes, three or four, by the time the big favourites hit the foot of Luz Ardiden.  Then it's every man for himself, and one of the most intriguing Tour stages that we've seen in many years.

I am going to hedge my bets on this one - it's just too difficult to call.  Whether Contador feels strong enough (he mentioned earlier in the week that he was worried about a knee injury, though has more recently said it's fine) is going to determine the rhythm of the climb.  I suspect Andy Schleck will counter-attack only if attacked first, but for him, today remains about not losing time.  His big efforts will come in the Alps.  Frank Schleck may prove the critical factor.  And as for Evans, impossible to know.  Our local experts have awarded him the yellow jersey already - I await one bad day to deny him, but it's anyone's guess.

Only time will tell, and it's fabulous to have such an open Tour once again.  I believe (as I know many of you do) that these wide open Tours are another cause for some optimism about reduced (not removed) doping in the sport.  Let's hope it's a great day!  And let's hope that some great power output data is made available - I'll be sure to follow up with analysis of whatever we do see.

But that's for tomorrow, for today, enjoy the racing!
Ross

Tour de France: a "rest day" from analysis, Jens Voigt fills in

Tour rest today: Jens Voigt fills in the gap

It's my rest day today.  A day late, relative to the race, but nevertheless, no analysis today. Possibly tomorrow either (busy period at work), but to get you through these two days, while we await the onslaught of the Pyrenees on Thursday, for entertainment alone, here are some clips of one of the sport's characters, Jens Voigt, who is always guaranteed to give a great interview.

Sport needs more characters who enrich the sport with their outspokenness and entertainment value, and Voigt is one of the best.  It's not for nothing that Voigt, convinced by team-mates to start a Twitter account, found himself with 30,000 followers within his first day!  Whether his tweets match his interviews, time will tell!  Speaking of Twitter, don't forget to follow us, for links, short thoughts and opinions as they happen in the course of our day!

I'm sure you'll be seeing much more of Voigt in the coming days as he rides in support of the Schleck brothers, but for now, enjoy some of the unique perspectives from the peloton.

And again, if you are reading this as an email, please click here to be taken to the site where you can watch the clips.

Jens Voigt following a big crash - "didn't crash on my head, didn't crash on my face"



Always optimistic about his team leader's chances



Best of all...Shut up legs - winning the battle of the mind



Johnny Hoogerland update

And lastly, speaking of characters in the sport, Johnny Hoogerland unwillingly became one of cycling's new colorful characters when he was launched into a barbed-wire fence during Sunday's stage, and then showed exceptional courage to keep riding.

Since then, his legend has grown (33 stitches later) and he's enriched the sport even more with quotes like "I did what felt like a few somersaults...I landed on the fence and I looked at my legs and thought, ‘Is this what cycling is about?"  And this one: "I know that I'll be in a lot of pain during the rest day. I hope I can recover. It's a pity but I'm a Zeelander. We're not easy to tear apart."

Hoogerland has continued, and today finished the 10th stage 5:59 down on the front group, no doubt continuing to recover and hopefully get strong enough for the big challenges that lie in wait on Thursday.

Enjoy Wednesday, and we will hopefully return with some analysis ahead of the mountain showdown!

Ross

Fasting for 24 hours and ending up with a bigger waist!? This may be a sign that you are losing abdominal fat

This is such a common phenomenon that you’d expect to see it discussed more often – people fasting for a non-negligible number of hours and ending up with a bigger waist. However, it is very difficult to find anything published on it. (Lyle McDonald discussed a related phenomenon on this post on whooshes and squishy fat.) I am not talking about only a perceived bigger waist; I am talking about measurably bigger. This frequently happens with folks who were obese, lost a lot of body fat, and are trying to get rid of the stubborn lower abdominal fat.

(Source [ironically]: Gograins.com.au)

Fasting and ending up with a bigger waist; how is that possible?

Contrary to popular belief, this is very unlikely to be due to the body turning muscle protein into glucose, and then converting that glucose into fat for storage in fat cells around the waist. When you are fasting, one factor strongly opposes that transformation. The body is in net body fat release mode, due in part to low circulating insulin, and thus body fat cells are essentially rejecting glucose. Blood glucose levels are maintained, to feed the brain, but uptake by adipocytes via GLUT4 isn’t happening.

So where does the bigger waist come from?

When people fast they typically drink water, quite often lots of it. A reasonable explanation for the bigger waist is that body fat cells store water in place of fat, as fat becomes energy. Since water is denser than fat, the stronger gravitational pull will lead to a larger bulge around the lower abdominal area, increasing waist circumference at the point it is widest. The amount of fat mass, however, is going down due to fasting.

In the obese, body fat cells generally become insulin resistant, even though many people believe the opposite to be true. This leads to the creation of new body fat cells (hyperplasia) to store the extra fat. If body fat loss is maintained over time, I’d expect the body to get rid of those fat cells that were created through hyperplasia during the obese period. The literature, however, seems to suggest that the number of body fat cells is set before adulthood, and does not change afterwards. I am skeptical, as the body seems to be very good at  getting rid of cells and tissues that are not used.

The loss of those extra body fat cells may bring the number of adipocytes to pre-obesity levels, but for many people quite some time is needed for that to happen. Often in the order of months; maintaining reasonably low body fat levels.

So don’t despair if you end up with a bigger waist around noon after skipping breakfast, or before dinner after fasting the whole day. That may be a good sign; a sign that you are actually losing abdominal fat.

Tour de France: Raining crashes as we build to the Pyrenees

Tour de France: Crashes reign in France, as we build to the Pyrenees

So the Tour has a new leader - Thomas Voeckler, who got himself into a break on Stage 9 to claim yellow off Hushovd's shoulders.  It wasn't the way many expected it to go - the 'script' was that Hushovd would relinquish his lead on Saturday's Stage 8 on a relatively tough finish up to Super Besse.  His likely successors in yellow were Evans and the Schleck brothers, who were seconds behind.  However, the big Norweigian held firm in the lead peloton.

Until Stage 9.  Now it will likely be Voeckler, who with the aid of a tactical decision by Garmin to shut down the chase, overhauled a 1:29 deficit to take over the race's overall lead.  And with a lead now at 1:49 over Luis Leon Sanchez (Stage 9 winner), and around 2:30 to all the pre-race favourites, he seems likely to wear yellow onto the slopes of the Pyrenees, which happens Thursday (which is Bastille day - extra motivation for the Frenchman!), and in particular, the finishing climb of Luz Ardiden.

However, the big story is yet again crashes.  Yesterday our post focused on head injuries, and carried the dramatic video of Chris Horner finishing with concussion after Friday's stage.  He didn't start yesterday, and today we lost another handful of big names - gone today are Alexander Vinokourov and Jurgen Van den Broeck - both team-leaders, who join Horner and Wiggins on the sidelines.  The casualty list does not end there - Garate, Pouls, Brit, Zabriskie - all abandoned during Stage 9 alone.  Contador crashed (twice), Millar was involved in a heavy fall, and all in all, it's been a race of attrition, and some of those withdrawals have been for very serious crashes.

The TV car joins in the act - Flecha and Hoogerland taken out

Perhaps the big talking point of Stage 9 (apart from Voeckler's yellow and Sanchez's win) was a unbelievable incident where two riders in a five-man break were taken out by a France TV car.  The car attempted to pass the five riders to their left, then suddenly encountered a tree on the left edge of the road and swerved back across, hitting Juan Antonio Flecha.  He went down hard and Johnny Hoogerland launched off into a field on the right of the road.

It was a horrific looking crash, particularly for Hoogerland, who looked like he could be impaled upside down on a pole, or caught up in barbed wire fencing off the road.

Below are two videos that show the incident - I found one on YouTube, and I can't guarantee that it will remain there for too long, but they both show the crash.  It's quite unbelievable. (again if you can't play the video as part of an email, click here and you'll be directed to the site where they do work)


Flecha Crash - Tour de France stage 9 by cyclingvids

A longer clip off YouTube, including a slow-motion repeat (may or may not work, no promises...)



The Tour de France is difficult enough without high speed collisions with tarmac and metal.  In fact, they are part of this race, though I don't remember as many serious incidents as there seem to have been this year (but my memory might be to blame for that).  The first week of the Tour, as the saying goes, is not where you win the Tour, but you can certainly lose it, and I would imagine that most of the big GC favourites will actually be looking forward to getting into the mountains.  Hard as they may be, the intensity and frenetic nature of the race may drop slightly.

For their efforts, and quite literally, blood, Flecha and Hoogerland were honoured with the award for most aggressive riders on today's stage - it's more of a courage award, and to be sure, to get up and ride after that is extra-ordinary - it highlights the unbelievable toughness of the Tour de France.

Hoogerland will also wear the King of the Mountains jersey, assuming he can recover from his injuries and take his place in the peloton come Tuesday morning's start.  Let's hope so, and let's hope that Flecha is equally able to recover.  It leaves a bad taste when race favourites are eliminated by crashes, and it's deflating when the dynamics and rhythm of the race are altered by these "random" events.  I too look forward to the mountains!

The Stage 8 Super Besse climb - not as intense as it was predicted to be

Just some very quick analysis - the climb up to Super Besse was billed as the first showdown between the GC contenders, particularly in the aftermath of Contador's time losses in Stage 1.  And Contador did attack, yes, but the overall intensity of the climb was not as high as many perhaps thought, and that would negated any attacks.  Little damage was done to the top 20 in the Tour, and that's highlighted by looking at the SRM power data for Chris Anke Sorensen.

As you'll recall from our video post, Sorensen is always a good indicator of the intensity at the front of the peloton in the climbs, because he was Andy Schleck's last man in 2010.  Jump to 2011, and he's doing the job for Alberto Contador.  So he was right there at the front of the group during the climb, and so his data paint a picture of the 'mood' of the race in the final six kilometers.

So, 6.4W/kg for the first 6 minutes, made of up a 445W, 6.9W/kg effort for the first 2:30 and then 385 W (6 W/kg) for the next 3:30.  Note that both green arrows in the graph above are in the wrong place - they should be 100 or more watts lower - the SRM guys do great analysis, and this is just a minor error.  The power output the report seems correct though, it's just their annotated arrows and text that are placed too high.

The road then dropped down for a short while, and then on the next upward pull, Sorensen attacked.  That attack is interesting, it was made up of an initial 30-second burst at 701 W (10.9 W/kg) and then 30 seconds at 444 W (6.9 W/kg again).  Overall, that minute averaged 572 W, but once followed, Sorensen rode comfortably to the finish line.

But the first few kilometers are most interesting.  The power output we saw from Sorensen there, in the range of 6.4 W/kg for six minutes, are really just a teaser of what you can expect come Thursday.  There, in the high mountains, on the Category 1 and HC climbs, the riders will have to sustain power outputs in the range of 6.4 W/kg for twenty minutes in order to be competitive.  And 6 W/kg for 45 minutes on the longer climbs.

So all in all, the Super Besse climb was not really all that intense.  It is thus unsurprising that no attacks were successful - the base pace was just not hard enough to have anyone in difficulty in the early part of the climb.  Also, I believe there was a headwind on the climb, which makes attacking doubly difficult.

Questions unanswered ahead of the rest day, and then into the Pyrenees

It was another intriguing stage, mostly because Contador did try to attack (though this data suggest that his attacks were not particularly potent and came off a mild starting intensity), and was pretty easily tracked by Evans and the Schleck brothers.   As a result, we are no closer to knowing whether Contador has recovered from the Giro or not.  Will he have the form in the Pyrenees, and even if yes, can he hold that form into the final week and the very tough Alps?  And has Andy Schleck timed it to perfection?  He has not shown anything like the form of Contador this year, but perhaps the first ten days of the Tour have seen him slowly ride towards his best.  And Cadel Evans?  Looks exceptionally sharp and strong, but the near hour-long climbs starting on Thursday are a new, different kind of test.

And at this stage, we are none the wiser.  It's going to be an interesting few days.  And it starts with a rest day tomorrow!

Ross

Last thought - imagine this was...

And last thought - here is a picture of Hoogerland immediately after the crash that you can see in the videos above.  I got this on Twitter (via Jason Gay of WSJ - @jasonWSJ), but can you imagine if Payton Manning crashed into a barbed-wire fence and returned to a game, you'd hear about it for the rest of your life.  Fill in the name from a sport of your choice, but it's true - cycling has a different standard of what is considered "normal" and what is celebrated.  The kind of courage shown to come back from this accident is rare.  Let's hope Hoogerland and Flecha are ready to ride, unaffected, by Tuesday!

The Tour takes on a new complexion

A new complexion for the Tour and a serious day of crashes

Today the Tour rolls into its first 'taste' of mountains, with a finish up to Super-Besse Sancy that will almost certainly see a change in the yellow jersey.  Thor Hushovd has commanded yellow for since the team-time trial, but his slim lead over a host of riders is likely to be erased over a stage that includes a Category 2 climb and a fairly tough pull up to the finish in Super Besse Sancy.

Hushovd has done himself proud in the first week, defending that one second lead on a fairly tough, but short climb to Mur-de-Bretagne, although we knew that he climbs well for a big powerful man.  However, the much longer Category 2 climb, and the eight to nine percent grades may prove too much, and this is where the smaller riders come through - climbing is all about power to weight ratio, for the newer followers of the sport.  And so these are the climbs where the ability to sustain 6 W/kg for upward of 30 minutes start to tell, as I introduced in our video post earlier this week. The stage profile is below, courtesy cyclingnews.com.

Tomorrow is another tough, interesting "roller-coaster" with three Category 2 climbs and three Cat-3 climbs, before a rest day, then a few days of "calm before the storm" when the race reaches the high mountains of the Pyrenees and Luz Ardiden on Bastille day, Thursday 14 July.

A dramatic day - Horner's startling symptoms a rare view into head injury

Yesterday, however, was a dramatic day for all the wrong reasons.  A relatively uneventful stage suddenly turned, in this case for the worse, at about 38km to go, when a crash took down two pre-race contenders, Brad Wiggins and Chris Horner, and caused big delays for a number of other notable riders, including Levi Leipheimer.

It was Horner's story that unfolded as the most dramatic, because he actually continued to ride, receiving some medical attention on the bike, but ultimately lost over 12 minutes to the peloton.  However, it was the story after the finish line that was most disturbing.  Below is a video, courtesy Bicycling.com, that shows Horner crossing the finish line where he is met by a Radioshack team helper.  That is followed by an interview with Team Director Johan Bruyneel and then more footage of Horner as he is taken into an ambulance.

It's disturbing because it captures the immediate effects of a head injury.  You will hear Horner repeatedly asking people whether he finished the stage, and when the crash happened.  "I don't understand...when did I crash though?  Has it been a long time?"  Later he asks "Did I finish with the group or no?  But I finished?" He is completely out of touch with what happened and it's really eye-opening, startling and disturbing footage.



A decision will be made this morning as to whether Horner can continue, but I doubt that he will, and in fact that he should (late addition - Horner has been confirmed as abandoning and will not start the stage today, but is doing better, his second scan clear).  Yesterday also saw the abandonment of Tom Boonen, who also sustained a head injury in a crash two days before.  Then there is the case of Mauricio Soler, the Colombian rider who was involved in a very serious crash during the Tour of Switzerland a few weeks ago, and he is recovering but showing signs of "serious cognitive deficits".

The dangers of head injury and the need for a standard policy

It's a stark reminder of one of the dangers of cycling that we rarely think about.  Traumatic brain injury is a big issue in contact sports, like American Football, where the long-term effects of repeated head injuries have been the subject of probes and debates at the highest levels in Congress.  Malcolm Gladwell once compared it to dog-fighting, so inherent in the sport was head injury and so severe the prognosis of players involved in repeated collisions.

Also, in rugby, our big sport down here in South Africa, the diagnosis and management of head injuries and concussion are a serious business.  I have a colleague who has been conducting research into rugby injuries at two junior national tournaments in the last few weeks, and he was telling me just the other day that they were seeing a relatively high number of concussions.  And with the same dramatic symptoms that you saw above - players who don't know their names for minutes after the injury, for example.  Most recently, during my trip to Edinburgh with the SA Sevens team, we lost a player in that epic final to a concussion, and it's alarming to spend time with an athlete immediately after that.  Spending even five minutes seeing the effects is a wake-up call to anyone to be informed and aware of the dangers of traumatic brain injury.

In cycling, the issue seems to need some kind of policy - this article interviews Dr Prentice Steffen on who makes the decision for a rider to continue when they have suffered a head injury.  In the case of Boonen, he rode on after injury, plus did one more stage, before abandoning.

The complexity of concussion

The diagnosis and management of concussion is extremely challenging.  For example, this article from Neurology earlier this year used a test called the King-Devick test as a means to diagnose concussion in boxers and MMA fighters, the goal being to validate a rapid sideline tool that could accurately pick up any neurological problems.  The researchers compared it to a more comprehensive test, the Military Acute Concussion Evaluation, and concluded that their King-Devick sideline test was an accurate and reliable tool of concussion.

This was followed by letter from two researchers who have published a great deal in the field, warning against the "lure of simplicity".  Their main points (the article is available through University libraries) are that there is still no "diagnostic gold standard" for concussion, so we don't really now how to measure one test against another.  It's not as though there is a globally accepted best way to diagnose concussion, and so any new test is kind of being compared against a moving target.

Also, the study didn't actually test diagnosed concussion, but only looked at cognitive performance before and after a fight.  Given that fatigue could also affect the result, and that their athletes were boxers or MMA fighters, how relevant is this kind of test to football, to rugby, or maybe to cycling, where a once-off trauma occurs?  And finally, effective diagnosis of concussion requires that there is some baseline test BEFORE concussion, so that you know what you're comparing test results to.  The ultimate conclusion was that any test, however promising, needs a whole lot of research to establish just how relevant it is for a given context or situation.

Now, I'm not about to make a call on who is correct, or whether the test is oversimplified.  That is a neurology debate for those with a lifetime of specific research in the field.  However, I use that debate to highlight a) that there are a number of different approaches to diagnosis of concussion;  b) that "quick and easy" may not be the the most effective; and c) there's no gold standard, and only limited consensus, even in sports where concussion is a very real part of the game.  For cycling, the policy seems "less mature" and perhaps it is time to assess just how head injuries are managed.

Cycling's "fog of war" and who makes the decision?

Having said all this, when a cyclist is completely confused, vomiting, or dizzy and can't remember being in a crash, then by any measure in the world, they should be correctly diagnosed.  In terms of the actual decision of whether a cyclist can continue, I suspect a lot is lost in the "fog of battle".

Not to make excuses, but yesterday, we saw a number of riders down at the same time, and a lot of attention directed at Brad Wiggins, and perhaps the race overlooked the severity of Horner's condition.  Then again, he was treated by the race's traveling medical car, and surely would have shown some symptoms.  I think the complexity comes because of the pressure to make a decision early, the general pressure of being in a race situation where time is of the essence, and also the desire of the rider to continue.

In the interview with Bruyneel above, he explains that Horner was shaken and confused, and people will suggest that perhaps he should have pulled him at the side of the road. We had a discussion on this on our Facebook page earlier today, but the bottom line is that neither the manager or the rider can decide.  The cyclist can't make the call - he is in a classic catch-22 situation because because if they are concussed, then they cannot diagnose it because they're completely unaware of their own symptoms!  

Similarly, the manager is in a difficult situation because he is exposed to all kinds of conflicting incentives - sponsor pressure, race pressure and of course the desire of the rider to continue.  He would also be unsurprised that a rider is "shaken" after a crash, so that alone doesn't constitute a definitive symptom.

In among this "fog of war", he must make a snap judgment, and deal with the pressure from a cyclist who almost certainly will want to continue.  The problem for cycling, then, is that a decision must be made quickly and at the side of the road, and will almost always be made without complete information. Even the sideline type test I mentioned above would take too long - a GC contender can afford only a few minutes before the whole race is compromised.  This further complicates cycling's problem in dealing with any injuries, and is reason why we often see guys soldier on with broken bones before abandoning after the finish line.

Then of course, there is the frightening revelation that sometimes, head injuries can be fatal without producing any cognitive impairments.  Think back to Natasha Richardson, the British actress who died after a head injury sustained during skiing.  She actually sent paramedics away because she felt recovered, and apparently behaved normally, until three hours later when a headache developed.  One day later, she was dead - these are absolutely frightening injuries.  And that's why now, more than ever, the decision must be made on medical grounds, and cycling needs some kind of policy.  But it's no easy solution, simply because of the practical concerns explained above.

To give you an example from rugby, many years of debate and discussion produced a battery of cognitive tests that is administered by neutral specialists, in consultation with the team doctors, before a decision is made.  And the default option is to be safe first, even if it is too conservative.  The player is pulled from the game, and then treated in the relative peace of a medical room.  The same 'luxury' is not true for cycling, and so the focus has seemingly been on diagnosing riders after the stage.  Steffen talks in the article about a modified test that he has developed, and this should probably be standard and Tour-wide, not the responsibility of each team.

That decision should clearly be made in the best interests of the rider - Tour riders will almost always want to continue.  This is true in other sports too, where players often have to be dragged off the field by doctors.  Remember, these are people who don't even know their name, or that they crashed at all, so they clearly can't provide a sound medical opinion that they are clear to continue riding.

Horner's power output data: A great pity to lose out on, but thank you for the openness

And finally, on the note of Chris Horner, it would be remiss of me to mention that Horner's withdrawal is a great shame because he is the most competitive rider in the GC who makes his power output data available.  His performances and numbers are a great barometer for what is really happening at the front of the race, because he has always been within touching distance of the overall leaders and stage winners - 3% here, 5% there.  His data has been fundamental to our analysis of what it takes to climb with the best in the Tour.

This year, his form suggested that he may be even closer, in contention for the whole mountain stage, and so we were looking forward to really seeing what it takes to mix it at the front of the race during high mountain finishes.  His accident and abandon are thus amplified in that it will also cost us the great insight he was helping us gain into Tour power outputs - it is a double shame, and perhaps a good opportunity to thank him for making the data available in the first place.  We wish all other cyclists would do the same.  And we wish Horner well in his recovery, and hope that he receives the very best medical care now.

Wiggins out - collar bone

Another big name out is Brad Wiggins, leader of Team Sky, who was involved in the same crash, but was immediately clearly in trouble.  His collar bone was broken and he was taken away in an ambulance.  For him, it's a huge shame, as it is for all the British hopes for a high overall finish in this year's Tour.  Wiggins' form had never been better, and so his loss will certainly have had an impact on the high mountain stages.

Looking forward

The Tour now heads for the hills, and then the mountains, with two "appetizers" in the Massif Central, and we'll cover any insights as they happen.  Let's hope for minimal negative drama, and that the action happens on the bikes as the race unfolds.

Ross

Tour de France: Stage 4 power output analysis

453 Watts for the final 2km: A look at Stage 4

Just a very short post as a follow up to the earlier post on the power output during the Tour de France.  And for this, credit to SRM, whose website is an absolute must for anyone really interested in crunching the numbers on the Tour.  The truth is, they do such a great job of breaking down the power files of their riders that it sometimes feels unnecessary to do it again myself, but there are some insights I'd like to try share regarding what happened on the climb up to the Mur-de-Bretagne.

So again we look at Chris Horner - 10th last year, a podium contender this year, he's going to continue to be a great barometer for what is going on at the very front end of the race.

Below is his power output file for the entire 172km (again, click to enlarge).

It shows some of the features we mentioned in our post earlier today - a relatively low average power output of 216 W (still significantly higher than the 176W of stage 1), but particularly in the flatter sections of what was a "bumpy" stage.   For long sections, the power output is below 180 W (the green line in the above graph), but that is also dictated by the profile of the stage - the black line is the altitude graph and if you look at that, combined with the pink trace showing speed, you get an idea that yesterday was a pretty up and down stage, fast then slow, high intensity over rolling terrain.  These types of days are often more taxing than longer, but steadier mountain stages. In fact, at first glance, the power output profile resembles an interval-type session.

But the real story is the final 15% of the stage, and in particular, the last 2km, where the race broke up and Alberto Contador attacked.  Horner's average power output for the final 25 km (which took only 31 minutes) was 318 W (5W/kg), building progressively towards the finishing climb, where it really ramps up.

The Contador attack actually created a small gap over Horner, who ended up 8 seconds down on the stage, but his power output file for those final 2km reveal just how intense the effort was at the front of the race.

So, some numbers.  Horner covered the final 2km in 4:16, with an average power output of 453 W.  The mass being used by SRM is 64kg, and that means that his final 4:16 was done at 7.1 W/kg.  There was a 2 min stretch in the middle, shown in the figure above where the power output was 502W, an enormous 7.8 W/kg.  Note the spikes in power and the not insignificant period of time spent above 540 W, mostly towards the bottom part of the climb.

Some physiological implications

It's too tempting not to try to interpret the physiological implications behind those numbers.  Unfortunately, to do so means making some assumptions.  If we assume a cycling efficiency of 23% (which is reasonable, I think, based on the measurements in elite riders, including Armstrong), then we can estimate that the energy cost of riding at this intensity is 28.3 kCal per minute.  That actually gels pretty nicely with what the SRM is reporting - 116 kCal over 4:16, or 27.2 kCal/min.

It's impossible to know what kind of oxygen cost is involved, because there you have to assume where the energy is coming from.  And for such short, high intensity efforts, that is much more difficult to do than for the longer climbs.  

But if you go to the furthest extreme (which estimates the lowest VO2, call it the "low case scenario") and assume only carbohydrates are providing the energy, then you can estimate a VO2 of 5.6 L per minute, or 87.52 ml/kg/min.  The trouble with this estimate is that it doesn't account for energy production from anaerobic sources and lactate (and hence without oxygen), and so that 87.52 ml/kg/min is likely to be an overestimate.  And the reality is that for an all-out effort like that over 4:16, a cyclist is probably at supra-maximal intensities, or very close to 100% VO2max at least.  For this reason, it would be fascinating to see heart rate data as well, so that we at least get some indication of where Horner is relative to his own ceiling.

Once the climbs lengthen, and we can make a safer set of assumptions over the energy sources, then this kind of calculation will become much more valuable.  For now, it's just illustrative and highlights just how close the limit the finishing drives are, and how remarkable a Tour rider has to be just to hang on when the attacks begin to come at the end of the day

Hopefully that little illustration from Stage 4 contributes to the earlier post.  Enjoy the finish of Stage 5!

Ross