The relationship between cardiorespiratory fitness, physical activity, and dietary quality

This study evaluated the relationship between cardiorespiratory fitness, physical activity, and dietary quality in a group of 20- to 40-year-old women (n = 34) who varied widely in levels of physical activity. Nutrient intakes were determined using 10 repeated 24-hr diet records, randomly assigned, over a 10-week period. Physical activity was determined on the same randomly assigned days using the Caltrac Personal Activity Computer. Cardiorespiratory fitness was assessed by two maximal graded treadmill tests with continuous metabolic monitoring at both the beginning and end of the 10-week period. Neither physical activity nor cardiorespiratory fitness was significantly correlated with nutrient density (nutrient/1,000 kcal). Intake of energy (kcal/kg body weight) was higher for the more physically active and fit women, leading to a significant increase in most nutrients consumed per kilogram of body weight.