To revive an old thread; I found this video of MTB World Champion Greg Minnaar.
http://www.youtube.com/watch?v=hwnGklmAcbU

The first couple of minutes show him doing some weight/core exercises. There are some similarities to the program I have just started doing this week. You can take a look on my blog:
http://www.thetallcyclist.com/2012/1...ngth-series-3/

Enjoy!