In the face of slippery mud inclement weather and rugged terrain trail runners need determination and focus. But being dressed for the challenge doesn't hurt. Once you've found a pair of trusty trail running shoes -- the most important piece of equipment in any runner's arsenal -- it's time to choose the rest of your gear. Here is a round-up of sports outfitters' latest developments for women trail runners. Hydration After studying the needs of athletes in the Mont-Blanc Ultra Trail Run The North Face developed the FL Race Vest designed specifically for ultra long-distance runners. Weighing just 325g the