New Guy

Hey folks, I'm starting to get into my bike and have started to work on training for a few off-road triatholons, and maybe an Xtera race. I live in Palmer township and have been riding the canal betwen Bethlehem and Easton but want to actuly get off the 4 foot wide path and hit some trails. I have heard alot about Jacobsburg state park, Any pointers to help get me started without killing my self.
Any help would be great. Thanks