Giro 2013 - Part II
The extreme weather conditions took away the main climbs of the last week of racing in the Giro: only the finish at the Tre Cime was left determine the final GC in the mountains.
Under a snow blizzard Vincenzo Nibali flew the last 3 km of the climb (370m of ascent) in 12'50", with a VAM = 1734 m/h equal to 5.78 w/kg.
Considering the average altitude of this tract (2115m above sea level) and recalling that at this altitude the partial pressure of O2 in the air is reduced by approximately 20% compared to a altitude of 500m above sea level, Nibali's performance extrapolated to sea level should be increased by at least 10%.
That gives us a VAM = 1907 m/h, equal to 6.35 w/kg.
Uran expressed a performance of 3.1% lower, Scarponi and Evans of 9.7% and 11.7% respectively (difference calculated from their average speed over the last 3 km).
In the uphill time trial of Polsa (20km for 44'29" of effort) Nibali expressed 5.9% more power than Scarponi and Uran and 11.9% more than Evans, who was already fading in condition.
In the first TT of Saltara (54.8 km lasting for more than 1h16min of effort) Evans had given in only about 0.7% of power to Nibali, Scarponi = 1.3% and Uran = 3.8%.
In the two TT's these differences in power were extrapolated from the square of the average speeds, assuming aerodynamic efficiency to be the same for the four riders.
At least 2 kg lighter compared to past seasons, Nibali has progressed both in climbing and time trialling, and clearly demonstrated to be the best in all the difficult situations in this year's Giro.