How hard was Paris-Roubaix? Power data reveals the true pain of the 'Hell of the North'

Published April 14, 2023 04:34AM

And the Strava files shared by some of the day’s protagonists back up that description.

Unfortunately, Mathieu van der Poel didn’t upload the file of his conquest of the “Hell of the North”, and Wout van Aert is one of the many pros to keep his power data out of public reach.

But a dive through the stats of the racers in the wheels of the “big two” reveals a lot.

This year’s Roubaix made for a six-hour interval workout over ancient cobbled tracks in what could be a whole different sport from the smooth roads and steady outputs of a Tour de France mountain stage.

Dozens of 1,000+W sprints and leg-burning VO2 Max efforts are a theme in the files of top-10 finishers John Degenkolb (DSM) and Laurenz Rex (Intermarché-Wanty-Gobert).

Degenkolb finished seventh after coming back from a disaster crash and uploaded a ride with a weighted power 334W. Right behind him, breakaway survivor Rex completed his day in “Hell” in 9th place with a weighted power of 342W.

For both the burly 82kg rouleurs, that’s 4.1W/kg. Doesn’t sound like a lot for a WorldTour pro? That’s because it’s only a very glimpse of the true story.

“You saw in the last few years that we go all out from the start. And it was the fastest edition today. Incredible. There was no breakaway,” Mathieu van der Poel said after he conquered the cobbled monument.

Battle for the break

There was no chance for the peloton to shoot the breeze and easily digest its eggs and rice when it rolled off the start in Compiègne.

Like so many of this spring’s classics, the battle for the breakaway was long, fierce, and fast. Everyone knows that in Roubaix the day’s early break can go far.

The first four-rider split only emerged from the mess after accelerations up to 80kph, and the first two hours of racing ripped along at an average of 50kph.

The files of both Degenkolb and Rex show the variability and intensity of the accelerations and lulls while the tight-wound peloton refused to break apart.

Their average powers for the first two hours were “only” 276W and 280W, but those numbers don’t do justice to the power spikes scattered through the paved opening 100km of their monument rides. Both Degenkolb and Rex’s numbers peak out at more than 1,300W handfuls of times during the near-eternal battle for the break.

And that’s in the first one-third of a six-hour race that packs more pavé than most of the peloton can countenance.

Those big accelerations and jagged power profiles were a trend that only intensified when Roubaix truly heated up.

Degenkolb in Wout’s wheel on the Wallers

Degenkolb made the day’s crucial selection when he marked out Van Aert and Jumbo-Visma’s cobble-smashing move over the Heveluy à Wallers segment.

The German veteran was called on to put out some 437W – an output similar to his FTP – over those three minutes of pavé.

Sure, that’s nothing special on a stretch of pavement on any given training ride. But doing it on a four-star section of ancient stones while choking on Van Aert’s fumes is something different.

A dive into the segment detail speaks to the difficulties of having to accelerate and decelerate while hunting the best line on the stones. Degenkolb twice jumps from around 200W to nearly 700W and then 900W in the 2.5km stretch.

And it’s those lung-burster surges that define Paris-Roubaix. Every sector is approached like a bunch sprint, and winning gaps are only made with a true wattbomb.

That start-stop, crit-style effort of Roubaix is illuminated in the wider view of Degenkolb’s file.

The 10km either side of the crucial Wallers segment saw the German make four separate 1000+ W accelerations over the space of around 10 minutes. The 34-year-old was blowing at some 168+ bpm through the hardest moments of that crucial section as he dangled dangerously close to his heart rate high.

Roubaix is touted as a race for big-power time trialists, but like Degenkolb’s data shows, if you can’t kick hard, a hella lot of times, that cobblestone trophy will never come your way.

Van der Poel mashes the pedals on the Mons-en-Pévèle

The next big shakedown of the day came on the notorious 90-degree bends and crumbling verges of the Mons-en-Pévèle.

Van der Poel was commited to ripping apart the race and uncorked a flurry of accelerations before, during, and after the gruelling cobblestone strip.

Rex, who rode up a level when he latched onto the favorites’ group on the Wallers, saw the elastic snap some 50km later.

“When I was with the favorites after Arenberg, I told myself that I had to keep up as long as possible to achieve a top 10,” Rex said. “The rhythm of Van der Poel in the Mons-en-Pévèle killed me, after which I chased.”

At a strapping 82kg, Rex’s 377W output on the Pévèle is nothing to get excited about.

But like with Degenkolb’s ride over Wallers, the segment detail shows each of Rex’s accelerations, decelerations, and moments of freewheeling in a yo-yo-ing power profile of pure lactate pain.

Rex was eventually gapped off the back of the group midway through the Pévèle, just ahead of the left-hander, and it’s there you can see the power numbers level out as the young Belgian rode solo and braced for his hunt for the top-10.

Crunch time on the Carrefour

Like so often before, the race was effectively decided on the Carrefour de l’Arbre.

A whirlwind five minutes saw Degenkolb crash out of contention, Van Aert and Van der Poel trade attacks, and the Jumbo-Visma captain lose his chances to a disaster-timed flat tire.

“It’s been a long time since I was up there in a final like this and I think I rode a really good race. It’s really disappointing to get the chance of a good result taking away like that,” Degenkolb said of his crash.

He averaged a huge 470W and rocketed 15bpm over the first 600 meters of the Carrefour before he bumped with Van der Poel and bit the grass verge. And though Degenkolb’s spare bike didn’t seem to have a power meter, the 71kph acceleration when he remounted his spare machine suggests he was in the form of his later life.

And when Van Aert then punctured out, Van der Poel said he recorded his best end-of-race power in his time-trial to the finish.

The fact that Degenkolb, Matej Mohorič, Alexander Kristoff and countless more uploaded rides Sunday where the power numbers cut out partway is testament to the chaos that is Roubaix.

Any rider that emerges on the velodrome free of crashes, bike changes and technical calamities after the 55km of cobblestones counts themselves blessed in their encounter with “Hell”.

And that’s while challenging for the cobblestone trophy that crowns one of the hardest days on the calendar.