Exercise reduces fat selection in female Sprague-Dawley rats.

This study investigates the relationship between exercise and dietary macronutrient selection. Female Sprague-Dawley rats (5 months old) were placed on a macronutrient self-selection diet for 15 wk. Three food cups, each containing a separate vitamin and mineral supplemented macronutrient, i.e., fat, carbohydrate, or protein, were placed in the cage. Animals were either sedentary (Sed) or treadmill exercised (Ex) at 20 m.min-1, 60 min.d-1, for 6 d.wk-1. Cumulative daily energy and macronutrient intake were determined during this period. Energy intake was not different between Sed and Ex, 211.4 vs 213.5 kjoules.d-1, respectively. However, macronutrient intake differed with less fat eaten for Ex than Sed (81.5 kjoules and 38% for Ex; 114.0 kjoules and 47% for Sed). Carbohydrate and protein intake did not differ significantly between groups. Fifteen weeks of exercise training decreased dietary fat selection, but daily energy intake was not affected.