Who said a flat stage was supposed to be easy?

Stage 12 of the Tour de France offered an undulating circuit, but with just a handful of categorised climbs it was supposed to be an opportunity for the sprinters.

And indeed stage winner Alexander Kristoff (Katusha), John Degenkolb (Giant-Shimano), Peter Sagan (Cannondale) and Arnaud Demare (FDJ.fr) were all among the riders to make it to the finish line in the lead group.

Andre Greipel (Lotto-Belisol), too, would have been there had it not been for a crash in the final kilometres.

However, any sense the stage was an easy one – a chance to just go through the motions before the peloton heads into the Alps on stage 13 can be firmly rubbished by the pros stats on route-tracking app Strava.

With temperatures in the 30s, the suffer score was ramped up and the intensity of their efforts certainly headed skyward too.

Laurens ten Dam (Belkin), for example, rode according to his zone distribution – available to premium users such as the Dutchman – showed just half of his ride was rode at ‘active recovery’ level, or with a power output south of 220 watts.

He was at threshold – between 361 watts and 420 watts – for nearly 20 minutes during the course of the day and pushed his VO2Max for just shy of nine minutes.

The difference between the pro riders and the amateurs can be seen by examining his heat rate analysis, recorded with his Pioneer, however.

For all but seven minutes of the stage, ten Dam’s heart beat was below 152bpm – a figure many amateurs would be delighted with on a moderate incline.