My name is Nathan Pennington. I am the founder of a running site called rundreamachieve.com. I have dealt with many failures and some successes in the sport. I have a 2.19.35 marathon best and love out sport. I try to help other runners and welcome you to visit anytime you wish. I wanted to ask this question because we all, as runners, have them. For me, it has been improper fueling during the marathon. It has cost me dearly at times and trying to master the taper. Wishing you all a blessed 2013 and hope to see you over at RDA.