Gender differences in amino acid use during endurance exercise. 
There are gender differences in the substrate used to fuel prolonged physical activity.  Males rely on carbohydrate and amino acids (97%), while females use predominantly fat (62%) to fuel endurance exercise.  This review looks at the mechanisms that regulate these gender differences, with a focus on amino acid metabolism.  Gender-selective nutritional recommendations are indicated for physically active individuals and some cardiac patients who engage in intense aerobic activity.