Fear is made up of many emotions. One that seems to play a large role for me is my level of confidence. Take for example, skiing (I went today with my family, so this is fresh in my mind). When I am confronted with terrain that appears beyond my ability, I immediately tense up and begin to doubt myself. I start to remember past experiences that did not go so well, like a bad wipeout that I had on similar conditions perhaps.
This is unfortunate because if I attempt to ski in a fearful state, my natural tendency is to lean back away from the danger ahead. This body position puts me at a disadvantage as my center of balance is shifted. I will mostly likely fall or get through the ski run in poor form. Given this, I will then perpetuate this cycle of fear the next time.
Getting to know some of these aspects, I can alleviate some of this fear by becoming better skilled at skiing, learning more strategies and tactics and avoiding more difficult terrain until I am ready. Of course, going head first and realizing that I did survive and that I did do it, could work wonders too!