Energy availability is defined as energy intake minus energy expended. Energy is taken in through food consumption. Our bodies expend energy through normal functioning as well as through exercise. In the case of female athlete triad, low energy availability may be due to eating disorders, but not necessarily so. Athletes may experience low energy availability by exercising more without a concomitant change in eating habits, or they may increase their energy expenditure while also eating less. Disordered eating is defined among this situation due to the low caloric intake or low energy availability.