My coach, training partner and good friend Frank Overton of FasCat Coaching walks us through an analysis of power output in a 'cross, specifically the Boulder Racing Series #1 at Valmont Bike Park during the 35A race this past Saturday. Frank recorded his power via his Quarq powermeter supplied by SRAM. The data is demonstrated with TrainingPeaks WKO+ software. Frank talks about the spikes in power and the need for various training techniques such as motor pacing and Tabatas as key ingredients to simulate the speed and 'spikiness' of power in a cross. 

Two words: holy crap. This is why we are not PROs. Christan Vandevelde is proving yet again why he's a freak:
Honestly, this is massively impressive. You should hit Dirk's blog for this article about Chritian yesterday at the TdF and link over to the TrainingPeaks site to check out the WKO files (if you have CyclingPeaks) to see his data. For a 155 pound guy (which Christian is), doing 415w for 5 minutes is off the charts. Tremendously difficult. I can 'also' do that (e.g. 400 + for 4-5 minutes). How? Doses of truckers speed and red bull chasers. No, seriously because I am 35 pounds heavier and just the application of that my 180lbs of Irish Fury to my pedals will raise the wattage....but it is the gravity/grade of hill that comes into play. Yup, power to weight. Sure I can do it, BUT I AM GOING 1/2 THE SPEED! For me to hang, beyond being doped, I'd have to be in the 550 to 600w range for that same duration of time which is crazy talk. This above is power to weight in action. Unbelievable.