Check this guy out
If you want to get faster check out bikejames.com
I know this sounds like spam but its not. I have just spent an hour looking through this part of the forum and there seem to be loads of disconnected fragments of advice. I'm no Elite in fact I don't go for XC much but my XC racing is constantly improving with some of his advice. Covers strength, intervals nutrition
Worth a look in the off season
Very good advice for beginners there.
Take stuff that you can not ride as a challenge and step your game up…don’t dumb the trail down!
Thanks for the link.
His blog is cool but his training programs are ace.
He dispels a lot of training myths that have been ported over from road cycling
I've worked with Jame's philosophy this season-less volume more intensity; in a nutshell it's worked very well and saved me oodles of wasted training time. I've improved my race performances this season with half the hours; seriously. He talks about tapping into your 100% on intervals and training like you race. It's focused on freeride and trail ride disciplines but I absorbed a lot of good stuff for XC racing.
His site has a ton of free good information. Bikejames.com