Roulston’s power from the Tour of Flanders
Interesting numbers: power reading…
– By Nick Squillari
Of the many unique privileges cycling fans have over other sports is access to a professional’s ride data. It is the ultimate insight into what goes on in a race. There’s an opportunity to break down the efforts of a rider into a set of numbers that relay information relating to power, heart rate, altitude gains, distance ridden and cadence. And anyone with a power meter can consider their efforts and draw a comparison… if you want to know you need to ride at World Tour level, a power meter goes a lot of the way to showing you.
RIDE was fortunate enough to have access to Serge Pauwels’ data from each stage of the Tour Down Under earlier this year – and the permission to publish it. It made for some interesting analysis of the Belgian’s performance in the stage race this January. At the end of the TDU we all had a great appreciation of what was required to make the top 20 of what is an early season race.
Before getting the complete SRM file from Hayden Roulston’s efforts in the Tour of Flanders, we published an exert of an interview with the New Zealander that quoted some of his power details from the Classic that was contested on the last day of March 2013. It was a little bemusing to read comments stating that his average power output was “not that high” on our Facebook page. A further exchange with ‘Roly’ and we had the complete file.
Here we take a look at some of the data from that day racing around Flanders. A considered analysis should foster a little more appreciation for how hard pro cyclists can push themselves.
Those who followed our analysis of Pauwels’ power files will be familiar with the terms functional threshold power (FTP) and power to weight ratio (w/kg). Given the nature of de Ronde looking at absolute power figures tells only part of the tale.
For example, Hayden’s one-second peak power was ‘only’ 1,221w. Breaking it down to w/kg a lot of club level riders can match his 15.7 w/kg. However how many club level riders could produce it after five and a half hours of racing?
Notwithstanding the 1,151w effort 10 minutes earlier, the 1,138w effort that followed just 30 seconds after his peak and that his average power (not normalised) was 294w up to that point in the race.
Another interesting peak power to look at is Roulston’s 20 minute peak. It is 95% of this figure that coaches will use as the basis for a FTP. Hayden recorded 380w for 20 minutes, which you could use to say his FTP would be 361w. Reality is the Radioshack-Leopard rider would be able to push much more for 20 minutes, however that his power at the hour mark was 343w.
So, in this instance, it’s not a bad metric to use.
Breaking this down in to w/kg is where it starts to put the “not that high” claim in to context. Hayden’s 20 minute w/kg was 4.9w/kg. There would be a few A -rade riders who can hold that power to weight, however what about 4.7w/kg for 30 minutes?
Or 4.4w/kg for 60 minutes? Or 4.2w/kg for 120 minutes?
Not forgetting that after 75 minutes you have your first of 28 power jumps of over 1,000w!
One other consideration is that during all this, Hayden was still required to make sure both he and his team leader, Fabian Cancellara, took in enough fluids and food. As the ride summary shows…
Roulston burned over 25,000 kJ in total (the kJ figure above is mechanical energy, not total energy expenditure) for the ride alone. In layman’s terms, that is the recommended energy intake for an office working male for three days. Is it any wonder when we watch a rider ‘bonk’ they are almost incapable of remaining upright, let alone turning the pedals.
It also stands to reason that Hayden posted a “DNF” for the race. Six hours of that level of intensity would have meant that the Kiwi making it all the way to the finish line would have been an enormous effort. However, by the time he abandoned his job was done; he helped set the platform for Stijn Devolder to deliver Cancellara safe and sound to the final climb up the Paterberg.
Hopefully this helps with a bit of perspective for what is required at the highest level and how just looking at a final average power can be misleading without context.
I also recommend the more curious riders out there to try a power meter and have a go at holding the power to weight numbers in the article (I’ll even spare you the 1,000w+ accelerations). No better way to gain appreciation than walking (or in this case, cycling) a mile or two in another person’s shoes.
– By Nick Squillari, @Tinea_Pedis
* * * * *