Power analysis: The 20 minutes that dropped Egan Bernal
On stage 15 of the Tour de France, we saw last year’s winner, Egan Bernal, fall from third on GC down to 13th overall, 8 minutes and 25 seconds behind Primoz Roglic. All of this occurred on the last climb of the day, the Grand Colombier, where Wout Van Aert’s pace up the switchbacks did Bernal in.
This leaves us with a question: What did Bernal’s last 20 minutes as a GC contender for this Tour de France look like?
Bernal was clearly on an off day, and that becomes even more obvious when we look at the power.
Bernal and Ineos don’t release race-day power files. But we do have Harold Tejada’s Strava file. Tejada rides for Astana Pro Team, and was in the lead group up the final climb of stage 15, but was later distanced. He did, however, make it up with the leaders much longer than Bernal did. So we can use his file to determine the demands of the race up the final climb.
Harold Tejada’s stage 15 stats:
- Height: 5 feet 11 inches (1.8 meters)
- Weight: 138.8 lbs. (63 kg)
- Total time: 5 hours 1 minute
- Distance: 116.28 miles ( 187.13 km)
- Average speed: 23.2 mph (37.34 km/h)
- Elevation gain: 11,686 feet (3,562 meters)
- Work: 4,543 kJs
- Average power: 252 W (4.0 W/kg)
- Average weighted power: 299 W (4.74 W/kg)
- Max power: 848 W
- Average heartrate: 139 bpm
- Max heartrate: 181 bpm
The race up to the base of the Selle de Fromentel
The ride to the base of the Selle de Fromentel took Tejada and the rest of the GC favorites 2 hours 28 minutes, covering a distance of 70 miles (112.6 km) at an average speed of 28.5 mph (45.86 km/h). In this time he averaged 201 watts (3.19 W/kg). Using Strava’s intensity metric, we can backwards calculate that Tejada’s FTP is approximately 378 W (6.0 W/kg), so the ride to the base of the climb was ridden at an IF of .53, or basically what one would do on a recovery ride. Easy if you’re tucked safely in the pack.
Selle de Fromentel
With a break up the road, the group was content to let Jumbo-Visma set the pace. Looking at the power graph for this segment would suggest that while the Tejada was climbing at the lower end of this threshold, there were no surges so it was just a matter of “tapping it out”.
Regardless, the pace was too much for several of Bernal’s teammates, leaving him with just two lieutenants (foreshadowing). This is in contrast to Primoz, who still had five teammates by the time they reached the top. Below are Tejada’s stats for this climb.
- Total time: 34 minutes 43 seconds
- Distance: 6.73 miles (10.83 km)
- Average gradient: 8%
- Average speed: 11.6 mph (18.66 km/h)
- Elevation gain: 2930 feet (893 meters)
- VAM: 1,543 m/h
- Average power: 357 W (5.67 W/kg)
- Intensity factor: .94
- Max power: 595 W
- Average heartrate: 164 bpm
- Max heartrate: 180 bpm
Col de la Biche
A short, nine-minute descent separated the top of the Fromentel and the base of the Col de la Biche. Once again, the pace being set by Jumbo-Visma was steady. There are no visible surges in Tejada’s power graph here. One other thing to note: the above segment includes a downhill portion before the top, giving riders a break, so it can be said that this was definitely the easiest climb of the day.
Below are Tejada’s stats for this climb.
- Total time: 26 minutes 53 seconds
- Distance: 5.58 miles (8.98 km)
- Average gradient: 7%
- Average speed: 12.5 mph (20.11 km/h)
- Elevation gain: 1938 feet (591 m)
- VAM: 1318 m/h
- Average power: 353 W (5.60 W/kg)
- Intensity factor: .93
- Max power: 757 W
- Average heartrate: 168 bpm
- Max heartrate: 175 bpm
The Lacets, Grand Colombier
Here I will focus on the first part of the Colombier, the “Lacets”, since it was here that Bernal was dropped by Wout Van Aert’s pacesetting.
The GC group reached the base of the climb 1 minute 45 seconds behind the two riders left from the day’s breakaway. Robert Gesink peeled off the front shortly after arriving at the base, leaving Van Aert to do the work. Here Bernal, positioned about mid pack, jersey open, splashing water on his head, already seemed uncomfortable.
With about 8 miles (12.8 km) to go and with the GC group about 17 seconds behind the last man standing from the day’s breakaway, the bottom dropped out for Bernal. Watching it live you could see Bernal go backwards all of a sudden. At first it seemed like a mechanical, but it quickly became clear he was in trouble.
Using Tejada’s stats we can see what kind of effort was being set before this happened:
- Total time: 11 minutes 21 seconds
- Distance: 2.5 miles (4.02 km)
- Average gradient: 7.3%
- Average speed: 13.5 mph (21.72 km/h)
- Elevation gain: 979 feet (298.4 m)
- VAM: 1,577 m/h
- Average power: 375 W (5.95 W/kg)
- Intensity factor: .99
- Max power: 597 W
- Avergae heartrate: 167 bpm
- Max heartrate: 174 bpm
While these numbers are out-of-this-world for mere mortals like you and me, they aren’t for Bernal. So what happened? Unfortunately there’s no one right answer here. But we can offer some insights and let you draw your own conclusions.
Was the pace too high?
Doubtful. Guillaume Martin was able to pace himself back into the lead group after having to come to a complete stop at the base of the climb. Additionally, looking at my previous article it would seem Bernal should easily have been able to stay with the front group.
Did the heat play a role?
CyclingTips asked Pogacar what he thought about the pace being set at this point and he offered this insight: “Yes, I think Van Aert was pulling really good pace. But the pace was really high all day. So not high peak powers but in general day was difficult and hot.”
The heat cannot be dismissed. The temperature on this part of the climb was 88°F (31.1°C). When exercising in the heat, your heartrate increases in order to help keep your body cool. Increased heartrate will increase your rate of perceived exertion. I can speak to this personally as last week the temperature in Boulder was 98°F (36.7°C) and my heartrate would suggest I was doing a sweet-spot effort, but I was only doing zone 2 watts.
What about a lack of teammates?
Jumbo-Visma seems to have stolen a page from Ineos’ playbook. They amass their riders at the front of the group and set a pace that doesn’t allow others to attack, but not so hard that they’re blowing themselves up either. Ineos/Sky has done this to great effect in the past. But Bernal reached the last climb with only two teammates left, which leads one to ask whether David Brailsford made the right call in how he divided up the team to participate in the races during the condensed racing calendar.
There is no clear “ah-ha” moment that I can point at and say, “that’s why Bernal was dropped”. It could be one of the above reasons, a mixture of them, or none of them. Suffice to say that Bernal simply “did not have it” on stage 15 of the Tour.