A Review of Factors Influencing Athletes' Food Choices.
We investigated the effect of a combined carbohydrate and energy deficit in the regulation of food intake during 1 d. Seven lean, male subjects were studied in a crossover design. After 7 d of consuming a baseline diet (40% of energy as fat, 45% as carbohydrate, and 15% as protein), subjects were deprived of carbohydrate for 24 h; baseline amounts of fat and protein were consumed but only one-third of the baseline amount of carbohydrate. On the following outcome day, subjects were free to select ad libitum from a selection of either high-carbohydrate or low-carbohydrate food. On the baseline diet subjects consumed on average 10.9 +/- 1.7 MJ/d (carbohydrate: 305 +/- 49 g/d; fat: 116 +/- 18 g/d) and there was no difference in baseline intake between the two phases of the crossover study. During the deficit day, intake was reduced to 7.7 +/- 1.2 MJ/d [carbohydrate: 110 +/- 25 g/d (66% reduction); fat: 116 +/- 18 g/d]. On the outcome day, energy intake from high-carbohydrate foods was on average 10.5 MJ/d (carbohydrate: 430 +/- 112 g/d; fat: 48 +/- 20 g/d) compared with 16.6 MJ/d from high-fat foods (carbohydrate: 312 +/- 84 g/d; fat: 258 +/- 78 g/d). We conclude that the restoration of an energy deficit is not the main factor determining acute food intake. Rather, the data support the hypothesis that, under the conditions of our experiment, the intake of carbohydrate required to maintain carbohydrate balance was a more important factor in the regulation of acute food intake than was the restoration of energy deficit is not.