Special environmental conditions such as excessive heat and humidity, cold and high altitudes require increased fluid intake to avoid dehydration. The degree of increased intake must take into account the athlete, the event, the duration and intensity of the event, and body composition, among other things. Careful attention to the amount of fluid lost during exercise and the replacement of that fluid is essential to the athlete's health. Further, as energy requirement s increase, the athlete should first consume the maximum carbohydrate calories, then dairy and protein foods to make up for energy expenditure. In reference to timing, individual athletes vary. Some are able to consume and digest large meals within an hour of intense exercise, but others must pace ingestion throughout the day. Athletes in heavy training may need to eat more than three meals and three snacks a day; glycogen synthesis and repletion are accomplished more easily with ingestion of a meal or snack high in whole-food carbohydrate within an hour of the end of exercise.

Training diet recommendations, including pre-exercise, during, and post-exercise, should first be translated into food choices consistent with food preferences and training schedules, says the paper. Noting again that the training diet should incorporate the principles outlined in the Dietary Guidelines for Americans and Canada's Guide for Healthy Eating, the paper declares the fundamental difference between an athlete's diet and that of the general population to be fluid intake.