Here are two interesting articles I stumbled across. The first contains some pro racers’ tips for nutrition during races. The second is an interesting article from Joe Friel about fatigue and the relationship to CTL/ATL.
http://www.triradar.com/training-advice/ironman-nutrition-pro-secrets/
http://www.joefrielsblog.com/2011/06/question-why-am-i-so-tired.html
Hope you find them interesting and/or useful.