The reduction of energy intake in EAMD rats in our study is in consistent with human studies. For example, Tomten and Høstmark found calculated energy intake and total energy expenditure were in balance in athletes with regular menstruate, while a statistically significant negative energy balance was found in female athletes with irregular menstrual cycles. As previous studies had shown that disorder of the HPO axis in female athletes seemed to be rely on the recognition of an energy imbalance in human body, Stafford considered this pathological phenomenon may be attribute to the lack of compensatory caloric intake confronting with significant energy expenditure.