Mountain Biking - How do I avoid dirt and grime getting into cables?

For the first time since I've been mountain biking, my brakes and derailleurs' cables got all full of mud and grime after riding under the rain this weekend.

What to do to avoid this in the future?
What's the best lubrication to use in cables, that doesn't attract dirt?

Did the mud and grime actually seem to effect performance? My cables see quite alot of crud on most rides, but always keep on doing the job. If they really need lube, a dry graphite spray would probably be the only non dirt attracting thing to use.

Yes, it seriously affected performance, and I had to take it to the shop. They cleaned them and put grease.
I wonder if putting grease was what caused the trouble in the first place, though.

I keep mine dry - after a wet ride I unhook the housing and wipe them down. Also, on occasion I buff the inner wire with steel wool the wipe with alcohol. Stay away from coated cables - they’ve given me nothing but troubles. Also, if using Shimano shifters and brakes, I've had the best luck using Shimano housing, the inner wire doesn’t seem to matter, just use a high quality one.

Originally posted by ofroading347
What to do to avoid this in the future?
What's the best lubrication to use in cables, that doesn't attract dirt?

An act of god. Just prey my friend.

Actually, grease is one of the best things you can use, but get used to cleaning housings every once in a while. Id say once every 10 good rides.

Ive also seen those bumbers that are connected to the wire and bump up against the housing end to keep things clean.. dont know how well they work as they are usually found on the low end bikes.