Power Analysis: Giro d’Italia stages 18-21
In this column, we dive into power numbers from the final four days of an unforgettable Giro d’Italia.
Heading out the door? Read this article on the new Outside+ app available now on iOS devices for members! Download the app.
The 2020 Giro d’Italia will go down as one of the most memorable grand tours in history. It was unpredictable from start to finish, with a dramatic finale reminiscent of a movie script: the two top riders enter the final time trial with everything to play for and nothing to lose. Equal on time after three weeks of racing across Italy, the fastest rider takes the title in Milan.
The Giro was a story of fallen heroes, and their ill-prepared protégés suddenly thrust into the spotlight. Cagey veterans like Vincenzo Nibali (Trek-Segafredo) and Jakob Fuglsang (Astana) were dropped in the final week, miles behind Team Sunweb and Ineos Grenadiers. Rohan Dennis almost single-handedly turned the Giro on its head with just four days to go. On the epic climb of the Stelvio, the Australian dropped everyone but Jai Hindley (Sunweb) and his teammate Tao Geoghegan Hart (Ineos Grenadiers). Two days later he was at it again on the Sestriere, but neither Dennis nor Geoghegan Hart could drop Hindley who took the Maglia Rosa by fractions of a second heading into the final time trial.
But in the end, the 24-year-old Brit was stronger – Geoghegan Hart smashed the final time trial, putting 39 seconds into Hindley, and winning his first-ever Grand Tour in the Giro d’Italia.
Stage 18 to Laghi di Cancano
It all began on Stage 18, the queen stage of this year’s Giro: 207km up and over the infamous Stelvio, before another uphill finish in Laghi di Cancano. The peloton climbed from kilometer 0, straight up the Camp Carlo Magno where the early breakaway was formed. Riders had to match nearly 6w/kg for 30 minutes just to stay in the group.
30 kilometers later, the pace had hardly slowed, and another group bridged across to the breakaway, making it 16 riders out front. The first two hours of racing went by in a flash, putting plenty of pain into the riders’ legs with still over 100km and the Stelvio to go. Brandon McNulty (UAE-Team Emirates) was sitting in the top 10 overall at the start of stage 18 and had to make a huge effort just to stay in the peloton on the first climb.
McNulty – first two hours of stage 18:
Avg power: 320w (4.7w/kg)
Weighted Avg power: 350w (5.1w/kg)
Peak 20min Power: 394w (5.8w/kg)
After 60km of flat to rest and regroup, the peloton hit the base of the Stelvio. The 24.8km ascent averages 7.4 percent and climbs all the way up to 2,746m elevation, meaning that high-altitude acclimatization comes into play when oxygen matters most. Team Sunweb took over proceedings at the base of the climb, but soon it was former world time trial champion Rohan Dennis who came to the front and blew the race to bits.
The pace set by Dennis dropped Nibali and Fuglsang, and soon it was Wilco Kelderman (Team Sunweb) who was dangling off the back. Dennis was pushing around 6w/kg for the majority of a climb, which ended up being a one-hour and eleven-minute effort — just the kind of effort at which the former world hour-record-holder excels.
Dennis – section from driving the pace on the Stelvio:
Avg speed: 19.5kph (12.1mph)
Avg power: 450w (6.2w/kg)
Gradient: 8 percent
Over the last 5km of the Stelvio, now riding at over 2400m, Dennis, Geoghegan Hart, and Hindley continued to put time into Kelderman, who was now over 40 seconds behind. After more than an hour on the Stelvio and now at high-altitude, the power had significantly dropped, but not the intensity. Every rider was at their limit, knowing that this climb could well decide their fate at the Giro d’Italia.
Geoghegan Hart – final 5km of the Stelvio
Avg speed: 17.1km/h (10.6mph)
Avg power: 350w (5.4w/kg)
The leading trio climbed the Stelvio in one hour and eleven minutes, at an average speed of 20.6kph and a VAM of over 1,500 meters-per-hour. By our calculations, that’s an estimated power-to-weight ratio of 5.5-5.7w/kg for over an hour, at high-altitude, and over five hours to one of the hardest stages of the Giro so far. These performances on the Stelvio are truly incredible, but the ride from Dennis is even more so. The Australian sat on the front for over half an hour, pulling Geoghegan Hart into the driver’s seat of the Giro, and setting up an epic finale over the next three stages.
Stage 20 to Sestriere
Stage 20 was the final mountain stage of the Giro d’Italia, and the last chance for the climbers to take time before the individual time trial in Milan. Three climbs up the Sestriere were on offer, once from the longer and shallower side, and twice from the steeper. The stage was set for one final mountain battle, and the Ineos Grenadiers wasted no time taking to the front and driving the pace.
Current world time trial champion Filippo Ganna (Ineos Grenadiers) help set the pace on the first climb up the Sestriere. Climbing up to 2,000m elevation, the Italian lined out the bunch with another impressive effort, pushing over 430w for the final 8km of the climb.
Ganna – first climb up the Sestriere
Avg Speed: 25kph (15.5mph)
Avg power: 432w (5.1w/kg)
Gradient: 5.5 percent
On the second and steeper climb up the Sestriere, Dennis went to the front and set an infernal pace that, again, left only two men on his wheel: Geoghegan Hart and Hindley. In fact, Dennis set almost the exact same pace that dropped nearly everyone on Stage 18.
Dennis – second climb up the Sestriere
Avg speed: 24.2kph (15mph)
Avg power: 440w (6.1w/kg)
Gradient: 8 percent
Dennis looked as strong as ever, pulling up and over the climb, all the way down the descent, and continuing to pull towards the final climb. He never flicked his elbow or even asked for help. He was a man on a mission. When the inevitable attacks came from Hindley, Dennis kept his own pace, clawing his way back, and again went straight to the front. The Australian was the ultimate domestique for Geoghegan Hart, a mountain goat, poker face, and flatland motor all in one.
Dennis – final 31km of stage 20
Avg power: 360w (5w/kg)
Weighted Avg Power: 390w (5.4w/kg)
In the end, only the final sprint could separate Hindley and Geoghegan Hart, with the Brit coming out on top and, thanks to time bonuses, going level on time with Hindley heading into the final time trial.
Attacks with 2.5km to go on stage 20
Avg Power: 470w (7.8w/kg)
Max power: 840w (14w/kg)
Avg power: 500w (7.7w/kg)
Max power: 920w (14.2w/kg)
Stage 21: Milan TT
While the mountains are all about power-to-weight ratios, flatland time trials are more about pure power and aerodynamics – and that’s exactly what we saw on stage 21, a 15.7km time trial from Cernusco sul Naviglio to Milan. With only fractions of a second separating them on GC, Geoghegan Hart and Hindley needed only to beat the other in order to take the Maglia Rosa. Geoghegan Hart set out first, pushing over 400w for the first 5km. The Maglia Rosa on the shoulders of Hindley was next out of the start house. In the first 5km, the Australian had already lost 10 seconds to Geoghegan Hart.
Stage 21 time trial – first 5km
Power: 410w (6.3w/kg)
Power: 370w (6.2w/kg)
Despite Hindley’s trying, Geoghegan Hart continued to extend the gap, reaching 20 seconds by the halfway point, and still increasing his pace on the road to Milan.
Stage 21 time trial – kilometers 4-8
Speed: 52.4kph (32.6mph)
Power: 430w (6.6w/kg)
Speed: 50.2kph (31.2mph)
Power: 370w (6.2w/kg)
In the end, Geoghegan Hart was the stronger rider on the day, taking a deserving Giro victory in the most unexpected circumstances. Hindley finished 39 seconds down, but went home with second place in the GC at the Giro d’Italia, a result that few expected but only some were surprised by. The 24-year-old Australian showed his class by winning the Herald Sun Tour in February and confirmed his bigger potential with a podium finish in his third-ever grand tour. But the story of the day – the man and the team of the Giro – is Tao Geoghegan Hart and the Ineos Grenadiers. Seven stage wins and the Maglia Rosa over three weeks of racing at the Giro d’Italia – not a bad Plan B for the British team.
Hindley – Strava: https://www.strava.com/pros/1760759
McNulty Stage 18 – Strava: https://www.strava.com/activities/4212104750/
Ganna Stage 20 – Strava: https://www.strava.com/activities/4237252075/
Power Analysis data courtesy of Strava and VelonCC