Submitted to: American Journal of Clinical Nutrition
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/24/2003
Publication Date: 3/1/2004
Citation: Paul, D.R., Novotny Dura, J., Rumpler, W.V. 2004. Interactions between gender and food intake on the relationship between energy expenditure and body composition. American Journal of Clinical Nutrition. 79:385-389. Interpretive Summary: Despite the widely held notion that individuals should increase physical activity to maintain or reduce body weight and body fat, physical activity is related to lower body fat levels in men but not women. This suggests that maintenance of a healthy body weight and/or composition, especially for women, may be more loosely related to physical activity than previously thought. We have conducted a study to confirm that there is a disconnect between physical activity and body fat in women but not in men, and to investigate the reason for the gender difference in this phenomenon. We found that the type of physical activities performed by men and women could not explain the differences. We also found that body fat was related to fat and protein intake in women, but not in men. We have concluded that dietary factors may be involved in the gender dependence of the relationship between body fat and physical activity. These results will be useful for scientists and health practitioners.
Technical Abstract: The relationship between physical activity energy expenditure (PAEE) and body fat (BF%) is not very strong in the general population. It is possible that variables such as gender and/or food intake may explain part of the poor coupling of these variables. This study was designed to determine the interactions of gender and food intake on the relationship between PAEE and BF%. Total energy expenditure (TEE), resting energy expenditure (REE), food intake (dietary interview), and body fat percentage (BF%) were measured on 93 healthy men and women. PAEE and BF% were significantly related for all subjects, but the relationship was significant for men only when genders were analyzed separately. TEE was significantly greater and negatively related to body fat in men, but not in women. There were significant relationships between BF% and fat, protein, and caloric intake in women only, and no relationship with carbohydrate intake in either gender. In sum, active men are more likely than active women to have lower BF%. A possible explanation for this relationship is the number of calories consumed and the intake of fat, protein, and total calories.