From the Gatorade Sports Science Institute:
Endurance athletes may benefit from improving the macronutrient content of their diets. Specifically, a diet rich in carbohydrates
(7-10 g/kg
), moderate in protein
(1.2-1.7g/kg
), and low in fat is recommended. Guidelines expressed in absolute grams rather than as a percent of calories may be most appropriate for athletes since total calorie intake is often insufficient. Consequences of chronic energy deficiency include weight loss, inability to adapt to training, diminished performance, muscle soreness, respiratory infections, and other symptoms characteristic of overtraining.
Carbohydrate and fluid consumption before, during, and after exercise has been shown to directly impact performance. Recommendations for carbohydrate intake include: consuming 1 g/kg an hour prior to exercise; 30-60 grams per hour during exercise; and 1.5 g/kg immediately after exercise. Nutrition professionals should guide athletes in defining appropriate foods and beverages to meet these recommendations. The use of sports drinks is recommended since they can help meet both carbohydrate and fluid needs.
Given the high volume of sweat loss that many athletes experience during endurance exercise, proper hydration is critical for optimal performance and safety. The goal is to match fluid intake with fluid loss as much as possible. Recommendations include: consuming 16 oz. of fluids 2 hours before exercise; 8-16 oz. of fluids 15 minutes before exercise; at least 8 oz. of fluids every 15 minutes during exercise, and 20 oz. of fluids for every pound lost during exercise. Intake of sodium and other electrolytes must be considered since electrolyte balance plays a major role in hydration status.
A limited amount of research has focused on micronutrient needs of endurance athletes. Requirements for some vitamins and minerals are known to be higher for endurance athletes than the normal population. For example, sodium and other electrolytes lost through sweat may be needed in greater amounts. Endurance athletes may benefit from higher intakes of B vitamins and antioxidants. Although needs for some micronutrients aren?t increased, consequences of deficiency may be greater or more immediate to endurance athletes than normal individuals.
There are numerous supplements marketed to endurance athletes. All athletes should use caution when considering the use of dietary supplements. It is necessary to evaluate supplements for safety, legality, and potential efficacy. Examples of supplements currently being researched for their role in endurance training and performance include antioxidants, glutamine, branched chain amino acids
(BCAA
), and glycerol.
http://www.gssiweb.com/reflib/refs/334/michellerockwell.cfm?pid=99&...
Here's a bunch of nutrition information for "endurance" training:
http://www.gssiweb.com/sportssciencecenter/topic.cfm?id=99
Enjoy.