Looking at the stage profile today, it didn’t take a tactical genius to figure out the race would be fought on the final climb. With a relatively uneventful ride to the foot of the climb and 15km straight up to the finish. The average percentage was 7.4% but more like 8.5% when considering the undulations near the top.
A high maximum power to weight for 40+ minutes was the key to success today and the ability to survive a few surges would definitely come in handy.
FTP and OBLA
Without getting into a debate about the differences between FTP (functional threshold power) and OBLA (onset of blood lactate accumulation) or LT (lactate threshold). The basic definitions are:
- FTP = the maximum average power a cyclist can maintain for one hour (performance measure – basically a TT)
- OBLA = is the exercise intensity at which lactic acid starts to accumulate in the blood stream (physiological measure – how the body produces the power)
FTP aims to predict OBLA, but is dependent on non physiological influences like motivation.
The sort of numbers these guys push for FTP is in the order of 6.7w/kg for the best (a number touted in the past as “likely doped”), but lets move on! Contador at 62kg has an FTP of 420w and Froome at 68kg is likely around 460w.
An entry level pro is around 5w/kg at OBLA.
Froome has a clever card to play in that he specifically trains for surges while riding just under FTP. Here is a link to an article on this very thing in the Guardian. The basic principle is to ride at a high pace (say 350w), surge at 650w for a few seconds, then settle back into 350w again. This trains the body to recover while still under a significant load. The short surge increases lactate production and requires the body to remove it while still riding at 350w.
In theory, the fastest way up the mountain is at the highest steady pace you can maintain, but in practice, there are other riders to shake off, respond to their attacks or change the rhythm. Racing is rarely even tempo, so training needs to prepare the rider to meet these demands. Kerrison, Sky’s coach, is one of the best at objectively breaking down training to meet the needs of racing.
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