The condition is most common in sports that emphasize leanness,  such as cross country running, gymnastics, and figure skating. Many of those who suffer from the triad are involved in some sort of athletics, in order to promote weight loss and leanness. The competitive sports that promote this physical leanness may result in disordered eating and be responsible for the origin of the female athlete triad. For some women, the disorder can have major health consequences. In addition, for some competitive female athletes, problems such as low self-esteem, a tendency toward perfectionism, and family stress place them at risk for disordered eating. Signs and symptoms
Clinical symptoms of RED-S may include disordered eating, fatigue, hair loss, cold hands and feet, dry skin, noticeable weight loss, increased healing time from injuries (e.g., lingering bruises), increased incidence of bone fracture and cessation of menses. Affected athletes may also struggle with low self-esteem and depression. Upon physical examination, a physician may also note the following symptoms: elevated carotene in the blood, anemia, orthostatic hypotension, electrolyte irregularities, hypoestrogenism, vaginal atrophy, and bradycardia.An athlete may show signs of restrictive eating, but not meet the clinical criteria for an eating disorder. They may also display subtle menstrual disturbances, such as a change in menstrual cycle length, anovulation, or luteal phase defects, but not yet have developed complete amenorrhea. Likewise, an athletes bone density may decrease, but may not yet have dropped below her age-matched normal range.
These signs can be considered "occult," as no one symptom may be severe enough to seek medical attention, leaving the triad to go unnoticed or untreated. Disordered eating
Energy availability is defined as energy intake minus energy expended. Energy is taken in through food consumption. Bodies expend energy through normal functioning as well as through exercise. In the case of RED-S, 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. While most athletes do not meet the clinical criteria to be diagnosed with an eating disorder such as anorexia nervosa or bulimia nervosa, many will exhibit disordered eating habits such as fasting, as well as avoiding certain types of food the athlete thinks are "bad" (such as foods containing fat). There are multiple factors that play in encouraging athletes to aim for a more lean body type, such as the culture and the individual. More severe examples of disordered eating habits may include binge-eating; purging; and the use of diet-pills, laxatives, diuretics, and enemas.By restricting their diet, the athlete may worsen their problem of low energy availability.