Core or Balance Training for Trail Running
As we all know, running the trails requires balance and agility in addition to strength and endurance. Here is an article about this very topic:
The Balancing Act of Trail Running
This article is posted on the web site of a Canadian company called Fitterfirst (http://www.fitter1.com/index.html). Check out their web site for great info and products on overall fitness including core strength training.