Nutrient intake of physically fit and unfit men and women

Participation in physical activity and following a diet low in fat, saturated fat, and cholesterol and high in fiber are important in the prevention and treatment of cardiovascular disease and other health problems. Despite the importance of both behaviors, little is known about the interactive role of diet and physical activity. The association between physical activity and diet has been studied, but data on the association between cardiorespiratory fitness (CRF), which is an objective measure of habitual physical activity, and diet are lacking in adults. This report examines nutrient intakes of men and women across low, moderate, and high fitness categories and compares the intakes to national dietary recommendations. It is the first step in examining the relationship between diet, CRF, and morbidity and mortality endpoints in the Aerobics Center Longitudinal Study (ACLS).

Between 1987 and 1995, 7959 men and 2453 women participating in the ACLS provided 3-d diet records and completed a preventive medical examination. CRF was measured using a maximal exercise test, anthropometric and other clinical variables were measured following a standardized protocol, and lifestyle factors were assessed with a medical history questionnaire.

After adjusting for potential confounders, there was a significantly lower percent of energy from fat and saturated fat across low, moderate, and high CRF categories. With additional adjustment for total energy intake, there was a significantly higher dietary fiber intake and a significantly lower cholesterol intake across CRF categories. The percentage of men and women meeting national dietary recommendations was higher at higher CRF levels.

Men and women with higher fitness levels consumed diets that more closely approached national dietary recommendations than their lower fit peers.